JP2018056207A - Method for manufacturing power storage module and power storage module - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a method for manufacturing an electricity storage module capable of improving workability of joining electrode terminals to each other. A method of manufacturing a power storage module 1 is a method of manufacturing a power storage module including first and second power storage devices 20A and 20B in which an electrode laminate 30 is housed in an exterior body 40. The electricity storage device includes a negative electrode terminal 60b1 and a positive electrode terminal 50b1 that are electrically connected to the electrode stack of the first electricity storage device and are pulled out from the outer body of the first electricity storage device. The electricity storage device of No. 2 is electrically connected to the electrode stack of the second electricity storage device and includes a negative electrode terminal 60a2 and a positive electrode terminal 50a2 that are drawn out from the outer body of the second electricity storage device. The module manufacturing method includes a step S40 of stacking the negative electrode terminal 60b1 and the positive electrode terminal 50a2 on each other, a step S50 of bonding the negative electrode terminal 60b1 and the positive electrode terminal 50a2 stacked on each other, and a negative electrode terminal 60b1 bonded to each other. And step S60 of folding back the positive electrode terminal 50a2. [Selection diagram] Fig. 11

Description

  The present invention relates to a method for manufacturing a power storage module including a plurality of power storage devices and a power storage module.

  There is known an electrochemical cell including an electrode body, an exterior body housing the electrode body, and a pair of electrode terminals drawn in the same direction from the same side of the exterior body (see, for example, Patent Document 1). .

JP 2014-179293 A

  It is generally performed to assemble a power storage module by stacking a plurality of electrochemical cells and electrically connecting the cells in series. In this case, a plurality of electrode terminals are arranged side by side along the stacking direction of the electrochemical cell, and the other electrode terminals arranged above and below the electrode terminals to be joined interfere with the work area and are joined. There is a problem that it is inferior.

  The problem to be solved by the present invention is to provide a method of manufacturing a power storage module and a power storage module that can improve the joining workability between electrode terminals.

[1] A method for manufacturing a power storage module according to the present invention is a method for manufacturing a power storage module including first and second power storage devices in which an electrode stack is accommodated in an outer package, wherein the first power storage device is And first and second electrode terminals that are electrically connected to the electrode stack of the first power storage device and are drawn from the exterior body of the first power storage device, The second power storage device is electrically connected to the electrode stack of the second power storage device and is pulled out from the exterior body of the second power storage device. The method for manufacturing the power storage module includes: a first step of overlapping the first electrode terminal and the fourth electrode terminal; and the first electrode terminal overlapped with each other. And the fourth electrode terminal A second step of bonding the a method for manufacturing a battery module comprising a third step of folding the first electrode terminal joined to each other and the fourth electrode terminal.

[2] In the above invention, the first and second electrode terminals are pulled out in substantially the same direction from the exterior body of the first power storage device, and the third and fourth The electrode terminal is pulled out from the exterior body of the second electricity storage device in substantially the same direction, and the first electrode terminal of the portion exposed from the exterior body of the first electricity storage device of the first electrode terminal. 1 is relatively larger than the second length of the portion of the second electrode terminal exposed from the outer package of the first electricity storage device, and the fourth electrode terminal of the first electrode 4th of the part exposed from the said exterior body of 2 electrical storage devices is with respect to 3rd length of the part exposed from the said exterior body of said 2nd electrical storage device of said 3rd electrode terminal Relatively large, the third step is the folded first first The length of the portion of the electrode terminal and the fourth electrode terminal exposed from the exterior body of the first and second power storage devices is at least one of the second length and the third length. The first electrode terminal and the fourth electrode terminal joined to each other may be folded back so as to be relatively small.

[3] In the above invention, the power storage module further includes a plurality of electric wires for voltage detection of the electric storage device, and the first step includes the first electrode terminal with the electric wires interposed therebetween. The fourth step includes overlapping the fourth electrode terminals with each other, and the second step includes collectively bonding the fourth electrode terminals, the electric wires, and the first electrode terminals. But you can.

[4] In the above invention, the power storage module includes a plurality of power storage units including the first and second power storage devices, and the exterior body includes a convex housing portion that wraps the electrode stack. A first sheet portion; and a second sheet portion that is substantially flat and on which the first sheet portion is stacked via the electrode stack, the first and the second of the power storage unit. Two power storage devices are stacked on top of each other so that the housing portions are in contact with each other, and the second electrode terminal of the power storage unit is joined to the third electrode terminal of the power storage unit, The method for manufacturing the power storage module includes a fourth step of stacking the plurality of power storage units so that the second sheet portions are in contact with each other before the first step, and after the fourth step. Before the second step The fourth electrode terminal in the other power storage unit stacked on the second power storage device of the power storage unit is replaced with the fourth electrode terminal in the power storage unit and the first electrode in the other power storage unit. A fifth step of bending so as not to overlap with the electrode terminal, wherein the first step includes the fourth electrode terminal in the power storage unit and the first electrode terminal in the other power storage unit. May be superimposed on each other.

[5] In the above invention, the third step may include folding back portions other than the joint portion between the first electrode terminal and the fourth electrode terminal joined to each other.

[6] In the above invention, a sixth step of covering the folded first electrode terminal and the fourth electrode terminal with a covering member may be further provided after the third step.

[7] A power storage module according to the present invention includes first and second power storage devices in which an electrode stack is accommodated in an exterior body, and the first power storage device includes the electrode stack of the first power storage device. First and second electrode terminals that are electrically connected to a body and are led out in substantially the same direction from the exterior body of the first power storage device, and the second The power storage device is electrically connected to the electrode stack of the second power storage device, and third and fourth electrode terminals drawn from the exterior body of the second power storage device, A first length of a portion of the first electrode terminal exposed from the exterior body of the first electricity storage device is from the exterior body of the first electricity storage device of the second electrode terminal. For the second length of the exposed part In contrast, the fourth length of the portion of the fourth electrode terminal exposed from the outer package of the second electricity storage device is the fourth length of the exterior of the second electricity storage device of the third electrode terminal. Relatively large with respect to the third length of the portion exposed from the body, the first power storage device is stacked on the second power storage device, the first electrode terminal and the fourth The electrode terminals are joined to each other, and the first electrode terminal and the fourth electrode terminal joined to each other are folded back, and the folded first electrode terminal and the second electrode terminal The length of the portion of the electrode terminal 4 exposed from the exterior body of the first and second power storage devices is relatively to at least one of the second length and the third length. It is a small power storage module.

  According to the present invention, the first and fourth electrode terminals before being folded are joined, and the joined first and fourth electrode terminals are folded so as not to protrude from the side of the power storage module. In this case, since the first and fourth electrode terminals can be joined at positions that do not overlap with other electrode terminals, it is possible to improve the workability of joining the electrode terminals.

FIG. 1 is a perspective view showing a power storage module according to an embodiment of the present invention. 2 is an exploded perspective view of a part of the power storage module shown in FIG. FIG. 3 is an equivalent circuit diagram of the power storage module shown in FIG. FIG. 4 is a plan view of the first power storage device according to the embodiment of the present invention. FIG. 5 is a cross-sectional view taken along line VV in FIG. 6 is a cross-sectional view taken along line VI-VI in FIG. FIG. 7 is a plan view of a second power storage device according to an embodiment of the present invention. 8A is a cross-sectional view taken along the line VIIIA-VIIIA in FIG. 7, and FIG. 8B is a cross-sectional view taken along the line VIIIB-VIIIB in FIG. FIG. 9 is a partial cross-sectional view illustrating a connection portion between the positive electrode terminal of the first power storage device and the negative electrode terminal of the second power storage device in the second power storage unit according to the embodiment of the present invention. FIG. 10 is a partial cross-sectional view illustrating a connection portion between the positive electrode terminal of the second power storage device of the first power storage unit and the negative electrode terminal of the first power storage device of the second power storage unit. FIG. 11 is a process diagram showing a method for manufacturing a power storage module according to an embodiment of the present invention. 12A and 12B are diagrams showing step S10 of FIG. 11, FIG. 12A shows a state where electrode terminals are overlaid, and FIG. 12B shows an electrode. The state which has joined the terminal is shown. FIG. 13A is a diagram illustrating step S20 of FIG. 11, illustrating a state where the power storage units are overlaid so that the second sheet portions of the exterior body are in contact with each other, and FIG. FIG. 12 is a diagram illustrating step S30 and step S40 illustrated in FIG. 11, in which a positive electrode terminal of a second power storage device of the first power storage unit and a second power terminal of a second power storage device of the second power storage unit are bent. The state which has piled up the negative electrode terminal of the 1st electrical storage device of this electrical storage unit is shown. FIG. 14A is a diagram showing step S50 in FIG. 11 and shows a state in which the electrode terminals are joined. FIG. 14B is a diagram showing step S60 in FIG. Indicates the folded state. FIG. 15A is a diagram showing step S70 shown in FIG. 11, showing a state in which the bent electrode terminal is covered with a covering member, and FIG. 15B shows step S80 shown in FIG. It is a figure and shows the state which is bending the positive electrode terminal of the 2nd electrical storage device of a 2nd electrical storage unit.

  Hereinafter, embodiments of the present invention will be described with reference to the drawings.

  1 is a perspective view showing a power storage module according to an embodiment of the present invention, FIG. 2 is a partially exploded perspective view of the power storage module shown in FIG. 1, and FIG. 3 is an equivalent circuit diagram of the power storage module shown in FIG. is there.

  As shown in FIG. 1, the power storage module 1 in the present embodiment includes five power storage units 10 </ b> A to 10 </ b> E. Note that the number of power storage units constituting the power storage module is not particularly limited, and can be set based on a voltage or the like required for the power storage module. The power storage module may include a single power storage device in addition to the plurality of power storage units.

As shown in FIG. 2, the first power storage unit 10A includes two power storage devices 20A and 20B. Although the structure of each power storage device 20A, 20B will be described in detail later, the pair of electrode terminals 50a ₁ , 60a ₁ (50a ₂ , 60a ₂ ) is led out in the same direction in any power storage device 20A, 20B. At the same time, the exterior body 40 is a power storage device of a type having a convex accommodating portion 421 only on one side. The first and second power storage devices 20A and 20B are stacked on each other.

As shown in FIGS. 2 and 3, the positive terminal 50a ₁ of the first power storage device 20A, and the negative terminal 60a ₂ of the second power storage device 20B, it is joined. Thereby, the first power storage device 20A and the second power storage device 20B are electrically connected in series. Further, in the present embodiment, the voltage detection line 15a _1, the positive terminal 50a ₁ of the first power storage device 20A, is interposed between the negative electrode terminal 60a ₂ of the second power storage device 20B, the electrode terminals 50a ₁ , 60a ₂ and voltage detection line 15a ₁ are joined together.

  The second to fifth power storage units 10B to 10E have the same configuration as that of the first power storage unit 10A, and include two power storage devices 20A and 20B that are stacked on each other.

As shown in FIG. 3, for any of the second to fifth power storage units 10B to 10E, the positive terminals 50b _{1 to} 50e _{1 of} the first power storage device 20A and the negative terminal 60b _{2 of} the second power storage device 20B. and ～60E _2, but by being bonded respectively, the first power storage device 20A and the second power storage device 20B are electrically connected in series. In the present embodiment, the voltage detection lines 15b _{1 to} 15e ₁ are connected between the positive terminals 50b _{1 to} 50e _{1 of} the first power storage device 20A and the negative terminals 60b _{2 to} 60e _{2 of} the second power storage device 20B. The electrode terminals 50b _{1 to} 50e ₁ , 60b _{2 to} 60e ₂ and the voltage detection lines 15b _{1 to} 15e ₁ are joined together.

The first power storage unit 10A and the second power storage unit 10B are stacked on each other as shown in FIGS. At this time, the positive terminal 50a ₂ of the first power storage unit 10A of the lower side, a negative terminal 60b ₁ of the upper side of the second power storage unit 10B, but are joined respectively. Thereby, the first power storage unit 10A and the second power storage unit 10B are electrically connected in series. Further, in the present embodiment, the voltage detection line 15a _2, a positive electrode terminal 50a ₂ of the first power storage unit 10A, is interposed between the negative terminal 60b ₁ of the second power storage unit 10B, the electrode terminals 50a ₂ , 60b ₁ and the voltage detection line 15a ₂ are joined together.

Similarly, the 2nd-5th electrical storage unit 10B-10E is also mutually stacked | stacked as shown in FIG.1 and FIG.2. At this time, the positive terminal _{50b 2 ~50d} 2 of the lower power storage units 10b to 10d, and the negative electrode terminal _{60c 1 ~60e} 1 of the upper energy storage unit 10C to 10E, but are joined respectively. Thereby, the 2nd-5th electrical storage unit 10B-10E is electrically connected in series. Further, in the present embodiment, the voltage detection line _{15b 2 ~15d} 2, a positive electrode terminal _{50b 2 ~50d} 2 of the lower power storage units 10b to 10d, the negative terminal _60c of the upper energy storage unit 10C~10E ₁ ~60e 1 The electrode terminals 50b _{2 to} 50d ₂ , 60c _{1 to} 60e ₁ and the voltage detection lines 15b _{2 to} 15d ₂ are joined together.

Incidentally, the positive electrode terminal 50e ₂ of the second power storage device 20B of the fifth power storage unit 10E located at the top serves as an external positive terminal of the battery module 1. A voltage detection line 15e ₂ is joined to the positive terminal 50e ₂ . Similarly, the negative electrode terminal 60 a ₁ of the first power storage device 20 </ b> A of the first power storage unit 10 </ b> A located at the lowest level also functions as the external negative electrode terminal of the power storage module 1. In this negative electrode terminal 60a _1, the voltage detection line 15a ₀ are joined.

The voltage detection lines 15a ₀ , 15a _{1 to} 15e ₁ and 15a _{2 to} 15e ₂ are connected to a protection circuit board (not shown). This protection circuit board monitors the voltages of the electricity storage devices 20A and 20B. Although not particularly shown, external devices are connected to the external terminals 50e ₂ and 60a ₁ through charge / discharge wires.

  The power storage module 1 in the present embodiment corresponds to an example of the power storage module in the present invention, the power storage units 10A to 10E in the present embodiment correspond to an example of the power storage unit in the present invention, and the first power storage device 20A in the present embodiment. Corresponds to an example of the first power storage device in the present invention, and the second power storage device 20B in the present embodiment corresponds to an example of the second power storage device in the present invention.

  Next, the first power storage device 20A and the second power storage device 20B will be described. In the following description, the detailed configuration of the first power storage device 20A and the second power storage device 20B of the second power storage unit 10B will be described as an example.

  4 is a plan view of a first power storage device according to an embodiment of the present invention, FIG. 5 is a cross-sectional view taken along line VV in FIG. 4, and FIG. 6 is a cross-sectional view taken along line VI-VI in FIG. 7 is a plan view of a second power storage device according to one embodiment of the present invention, FIG. 8A is a cross-sectional view taken along line VIIIA-VIIIA in FIG. 7, and FIG. It is sectional drawing along the VIIIB-VIIIB line.

  First, the first power storage device 20A will be described with reference to FIGS.

  The first electricity storage device 20A shown in FIGS. 4 to 6 is a flat laminate type lithium ion capacitor. The first power storage device 20A is a lithium ion capacitor having a length of about 80 mm, a width of about 55 mm, and a thickness of about 3.5 mm, and is classified as a small size. In addition, the dimension of 20 A of 1st electrical storage devices is not specifically limited to said numerical value. The power storage device is not limited to a lithium ion capacitor, and may be another power storage device such as a lithium ion secondary battery or an electric double layer capacitor.

The first power storage device 20A includes an electrode stack 30, an outer package 40 that houses and seals the electrode stack 30, and electrode terminals 50b ₁ and 60b ₁ that are electrically connected to the electrode stack 30. It is equipped with. The exterior body 40 is filled with an electrolytic solution (not shown).

The electrode stack 30 in the present embodiment corresponds to an example of the electrode stack in the present invention, and the outer package 40 in the present embodiment corresponds to an example of the outer package in the present invention. Moreover, the negative terminal 60b ₁ in the present embodiment is equivalent to an example of the first electrode terminals in the present invention, the positive electrode terminal 50b ₁ of the present embodiment corresponds to an example of the second electrode terminal of the present invention.

  The electrode stack 30 includes a plurality of positive plates 31, a plurality of negative plates 32, and a plurality of separators 33. The positive plates 31 and the negative plates 32 are alternately stacked via the separators 33. Yes. In addition, the number of the positive electrode plate 31, the negative electrode plate 32, and the separator 33 which comprises the electrode laminated body 30 is not specifically limited.

  As shown in FIG. 5, each positive electrode plate 31 includes a positive electrode current collector 311 and a positive electrode layer 314, and each positive electrode current collector 311 has a main body portion 312 and a lead portion 313. The main body 312 is a rectangular thin plate having a large number of through-holes, and specifically includes an expanded metal, a punching metal, a net, a foam, and the like. Specific examples of the material constituting the main body 312 include metal materials such as aluminum and stainless steel. The through-hole formed in the main body portion 312 functions as a moving path for the electrolyte and lithium ions. The positive electrode layer 314 is provided on both surfaces of the main body 312. The uppermost positive electrode plate 31 is provided with a positive electrode layer 314 only on the lower surface of the main body 312.

The lead portion 313 is a strip-like thin plate having no through hole, and is made of the same material as that of the main body portion 312 described above. The lead portion 313 extends from the vicinity of one end of one short side of the main body portion 312 (the upper end of the left side in FIG. 4), and the leading end of the lead portion 313 together with the other lead portions 313 is the positive terminal 50b. ₁ is joined to a rear end portion 501 (described later). In the present embodiment, the lead portion 313 is integrally formed with the main body portion 312, but is not particularly limited thereto, and the lead portion 313 and the main body portion 312 may be formed separately and then joined together.

  The positive electrode layer 314 is formed by attaching a positive electrode active material or the like to the main surface of the main body 312 of the positive electrode current collector 311 by coating or the like. The positive electrode active material is not particularly limited as long as it can reversibly carry lithium ions, and examples thereof include graphite and activated carbon. Note that the positive electrode layer 314 may contain a conductive material, a binder, or the like as necessary.

  As shown in FIG. 6, each negative electrode plate 32 also includes a negative electrode current collector 321 and a negative electrode layer 324, and each negative electrode current collector 321 has a main body portion 322 and a lead portion 323. The main body portion 322 has a large number of through holes and is a rectangular thin plate having the same size as the main body portion 312 of the positive electrode current collector 311 described above. Specifically, an expanded metal, a punching metal, a net, and a foamed body Etc. Specific examples of the material constituting the main body 322 include metal materials such as stainless steel, copper, and nickel. The through-hole formed in the main body portion 322 functions as a moving path for the electrolyte and lithium ions. The negative electrode layer 324 is provided on both surfaces of the main body portion 322.

The lead portion 323 is a belt-like thin plate having no through hole, and is made of the same material as that of the main body portion 322 described above. The lead portion 323 extends from the vicinity of the other end (the lower end of the left side in FIG. 4) on one short side of the main body portion 322, and the tip of the lead portion 323 is connected to the negative lead terminal 60b together with the other lead portions 323. ₁ is joined to a rear end portion 601 (described later). In the present embodiment, the lead portion 323 is integrally formed with the main body portion 322, but is not particularly limited thereto, and the lead portion 323 and the main body portion 322 may be formed separately and then joined together.

  The negative electrode layer 324 is formed by attaching a negative electrode active material or the like to the main surface of the main body 322 by coating or the like. The negative electrode active material is not particularly limited as long as it can reversibly carry lithium ions, and examples thereof include graphite and activated carbon. Note that the negative electrode layer 324 may contain a conductive material, a binder, or the like as necessary.

  The separator 33 is durable to an electrolytic solution, a positive electrode active material, a negative electrode active material, and the like, and is composed of a porous body that has communication holes but does not have electronic conductivity. Specifically, the separator 33 is composed of a nonwoven fabric or a microporous film formed from cellulose, polyethylene, or the like. The separator 33 is impregnated with an electrolytic solution. In order to prevent leakage, a gel or solid electrolyte may be used instead of the electrolyte, and in this case, the separator 33 may be omitted.

As a specific example of the electrolytic solution, an aprotic organic solvent electrolyte solution of a lithium salt can be exemplified. The lithium salt is not particularly limited, for _example, can be used LiPF _6, LiBF 4, LiFSI, the LiTFSI. Specific examples of the aprotic organic solvent include carbonates such as ethylene carbonate, propylene carbonate, dimethyl carbonate, diethyl carbonate, and ethyl methyl carbonate. In addition, you may use the liquid mixture which mixed 2 or more types of these aprotic organic solvents.

  Furthermore, the electrode laminate 30 in the present embodiment includes a lithium electrode 34 as shown in FIG. The lithium electrode 34 is stacked further below the lowermost negative electrode plate 32 via a separator 33, and functions as a lithium supply source that supplies lithium ions to the negative electrode plate 32. The lithium electrode 34 includes a lithium electrode current collector 341 and a lithium layer 344, and the lithium electrode current collector 341 includes a main body part 342 and a lead part 343. The main body portion 342 is a rectangular thin plate having the same size as the main body portion 312 of the positive electrode current collector 311 described above, and is made of, for example, a metal material such as copper or stainless steel.

The lead portion 343 is a strip-shaped thin plate made of the same material as the main body portion 342 described above. The lead part 343 extends from the vicinity of the other end (the lower end of the left side in FIG. 4) of one short side of the main body part 342, and the tip of the lead part 343 is a negative electrode together with the lead part 323 of the negative electrode plate 32. is joined to the rear end portion 601 of the terminal 60b ₁ (see below). In the present embodiment, the lead portion 343 is formed integrally with the main body portion 342. However, the lead portion 343 is not particularly limited thereto, and the lead portion 343 and the main body portion 342 may be formed separately and then joined together.

  The lithium layer 344 is a metal foil that is pressure-bonded to the surface of the main body 342 of the lithium electrode current collector 341. The lithium layer 344 is made of a material containing at least lithium and capable of supplying lithium ions. Specific examples of the material constituting the lithium layer 344 include a lithium-aluminum alloy.

In the present embodiment, the lithium electrode 34 constitutes a part of the negative electrode. That is, the lead portion 343 of the lithium-electrode current collector 341 is connected to the negative terminal 60b _1, it is possible to carry lithium ions to the negative electrode active material of the negative electrode layer 324. In order to smoothly carry lithium ions on the negative electrode, the lithium electrode 34 is preferably disposed so as to face the negative electrode plate 32.

  In addition, a lithium electrode is not limited to the form shown in FIG.5 and FIG.6. For example, although not particularly illustrated, (1) a configuration in which a negative electrode plate is further provided on the uppermost positive electrode plate and a lithium electrode is disposed on the negative electrode plate, or (2) two central regions of the electrode laminate are provided. A lithium electrode may be interposed between the negative electrode plates.

  As shown in FIGS. 4 to 6, the outer package 40 is formed by folding a rectangular laminate film 41 into two at a bent portion 44 and heat-sealing the other three sides excluding the bent portion 44. ing. The exterior body 40 includes a convex first sheet portion 42 that covers the electrode laminated body 30 from above, and a flat second sheet portion 43 that holds the electrode laminated body 30 from below. Yes.

  The laminate film 41 is a flexible film that can be bent. As shown in the enlarged view of FIG. 5, the laminate film 41 includes a metal foil 41a made of aluminum or the like, and first and second resin films 41b and 41c laminated on both surfaces of the metal foil 41a, respectively. It is equipped with. The 1st resin film 41b laminated | stacked inside the metal foil 41a is comprised from the resin material excellent in electrolyte solution resistance and heat-fusion property. On the other hand, the 2nd resin film 41c laminated | stacked on the outer side of the metal foil 41a is comprised from the resin material excellent in electrical insulation.

  The first sheet portion 42 has a housing portion 421 and a flange portion 422. The accommodating portion 421 is formed by processing the first sheet portion 42 into a concave shape from the inside by drawing or the like. As a result, the accommodating portion 421 has a shape protruding in a convex shape toward the outside. The accommodating portion 421 has a size that can accommodate the electrode laminate 30 described above, and can wrap the electrode laminate 30. The flange portion 422 is provided on three sides of the accommodating portion 421 excluding the bent portion 44 described above.

  On the other hand, the second sheet portion 43 is not formed with an accommodating portion or the like, and the second sheet portion 43 has a substantially flat shape.

In the state where the electrode laminate 30 to which the electrode terminals 50b ₁ and 60b ₁ are connected is accommodated in the accommodating portion 421 and the laminate film 41 is folded in two at the bent portion 44, the flange portion 322 of the first sheet portion 42, The peripheral portion of the second sheet portion 43 is heat-sealed. Thereby, the electrode laminate 30 is accommodated between the first and second sheet portions 42 and 43, and the electrode laminate 30 is sealed inside the exterior body 40.

The positive electrode terminal 50b ₁ is a band-shaped member made of a metal material such as aluminum or an aluminum alloy, and has a flat shape throughout. The rear end portion 501 of the positive electrode terminal 50 b ₁ is located inside the exterior body 40. The rear end portion 501 of the positive terminal 50b _1, lead portions 313 of the positive electrode plate 31 is joined. The positive electrode terminal 50b ₁ is drawn outward from the brother portion of the outer package 40 from one short side 45 of the outer package 40 toward one direction (left side in FIG. 5), and the tip of the positive electrode terminal 50b ₁ The portion 502 is located outside the exterior body 40. Further, the sealant resin layer 51 is interposed between the positive terminal 50b ₁ and the outer body 40. Incidentally, the positive electrode terminal 50b ₁ of the surface may be formed a plating layer such as nickel or tin.

The negative terminal 60b ₁ is composed of a single strip-shaped member having a flat shape throughout. The negative electrode terminal 60b ₁ are copper is composed of a metal material mainly composed of, in particular can be exemplified copper or a copper alloy. Furthermore, in the present embodiment, the negative electrode terminal 60b ₁ of the surface, the nickel-plated layer composed of nickel is formed. Note that a nickel plating layer may not be formed on the surface of the negative electrode terminal 60b ₁ or a plating layer made of another metal material may be formed instead of nickel.

The rear end portion 601 of the negative electrode terminal 60 b ₁ is located inside the exterior body 40. The rear end portion 601 of the negative electrode terminal 60b _1, lead portions 323,343 of the negative electrode plate 32 and the lithium electrode 34 is joined. Similarly to the positive electrode terminal 50b ₁ , the negative electrode terminal 60b _{1 is} also drawn out from the inside of the outer package 40 toward one direction (left side in FIG. 4) from one short side 45 of the outer package 40. cage, the tip portion 602 of the Tomake terminal 60b ₁ is located outside of the exterior body 40. Further, the sealant resin layer 61 is also interposed between the Fukyokuko 60b ₁ and the outer body 40.

As shown in FIG. 4, in the first power storage device 20A, the negative terminal of the portion exposed from the outer package 40 of 60b ₁ length L _{1 (hereinafter,} also simply as "the first length L _1" referred to.) The , Which is relatively larger than the length L _{2 of the} portion exposed from the exterior body 40 of the positive electrode terminal 50b ₁ (hereinafter, also simply referred to as “second length L ₂ ”) (L ₁ > L ₂ ). In the present embodiment, the first length _{L 1} of the negative electrode terminal 60b _1, to the second length _{L 2} of the positive electrode terminal 50b _1, more than twice is set to a length _{(L 1} ≧ 2 × L ₂ ).

Corresponds to the first example of a length of the first length L ₁ is the present invention in this embodiment, corresponds to an example of a second length the second length L ₂ in the present invention in this embodiment To do.

  Next, the second power storage device 20B will be described with reference to FIGS. 7, 8A, and 8B.

As shown in FIG. 7, the second power storage device 20B has the same configuration as the first power storage device 20A described above, except for the shapes of the positive electrode terminal 50b ₂ and the negative electrode terminal 60b ₂ . The negative electrode terminal 60b ₂ in the present embodiment corresponds to an example of a third electrode terminal in the present invention, and the positive electrode terminal 50b ₂ in the present embodiment corresponds to an example of a fourth electrode terminal in the present invention.

The negative terminal 60b ₂ of the second power storage device 20B, as shown in FIG. 8 (B), the outer portion of the exterior body 40 has two bent portions 62 and 63. The first bent portion 62 is a root portion to derive from the short sides 45 of the exterior body 40, and is formed by the negative electrode terminal 60b ₂ are folded upward (downward in FIG. 2). On the other hand, the second bent portion 63, the tip side of the root portion, and is formed by the negative electrode terminal 60b ₂ are folded downward (upward in FIG. 2). Note that by bending without folded negative electrode terminal 60b _2, may form a second bent portion 63.

In the second power storage device 20B, the length L _{4 of the} portion of the positive electrode terminal 50b ₂ exposed from the exterior body 40 (hereinafter, also simply referred to as “fourth length L ₄ ”) is the length of the negative electrode terminal 60b ₂ . It is relatively long (L ₄ > L ₃ ) with respect to the length L _{3 of the} portion exposed from the exterior body 40 (hereinafter also simply referred to as “third length L ₃ ”). In the present embodiment, the fourth length L ₄ of the positive electrode terminal 50b ₂ is set to a length that is at least twice as long as the third length L ₃ of the negative electrode terminal 60b ₂ (L ₄ ≧ 2). × L ₃ ).

The first length L ₁ of the negative electrode terminal 60b ₁ in the first power storage device 20A and the fourth length L ₄ of the positive electrode terminal 50b ₂ in the second power storage device 20B are substantially the same length. (L ₁ = L ₄ ). Further, the second length _{L 2} of the positive electrode terminal 50b ₁ of the first power storage device 20A, and the third length _{L 3} of the negative terminal 60b ₂ of the second power storage device 20B, folding the negative terminal 60b2 The length is slightly longer than the length of the length, but is substantially the same length (L ₂ = L ₃ ).

Third length L ₃ corresponds to an example of a third length in the present invention in this embodiment, corresponds to an example of a fourth length of the fourth length L ₄ is the invention according to this embodiment To do.

  The second power storage unit 10B is configured by stacking the first and second power storage devices 20A and 20B described above.

  FIG. 9 is a partial cross-sectional view illustrating a connection portion between the positive electrode terminal of the first power storage device and the negative electrode terminal of the second power storage device in the second power storage unit according to the embodiment of the present invention, and FIG. 10 illustrates the first power storage. It is a fragmentary sectional view which shows the connection part of the positive electrode terminal of the 2nd electrical storage device of a unit, and the negative electrode terminal of the 1st electrical storage device of a 2nd electrical storage unit.

Specifically, as illustrated in FIG. 9, the first and second power storage devices are in a state where the second power storage device 20B is inverted with respect to the first power storage device 20A and the housing portions 421 are in contact with each other. 20A and 20B are stacked on each other. At this time, the lead-out directions of all the electrode terminals 50b ₁ , 50b ₂ , 60b ₁ , 60b ₂ of the first and second power storage devices 20A, 20B are substantially the same.

  In this case, in the second power storage unit 10B, a relatively long negative electrode terminal 60b1 among the electrode terminals of the first power storage device 20A, and a relatively long positive electrode terminal 50b2 among the electrode terminals of the second power storage device 20B, Are arranged opposite to each other. Similarly, in the second power storage unit 10B, a relatively short positive terminal 50b1 among the electrode terminals of the first power storage device 20A, and a relatively short negative terminal 60b2 among the electrode terminals of the second power storage device 20B, Are arranged opposite to each other.

Further, as shown in FIG. 7, the negative electrode terminal 60b ₂ of the second power storage device 20B is at the tip-side portion than the second bent portion 63, joined to the positive terminal 50b ₁ of the first power storage device 20A Has been. At this time, in the present embodiment, the voltage detection line 15b ₁ is interposed between the positive electrode terminal 50b ₁ of the first power storage device 20A and the negative electrode terminal 60b ₂ of the second power storage device 20B, and the electrode terminal 50b ₁ and 60b ₂ and the voltage detection line 15b ₁ are joined together.

The voltage detection line 15b ₁ is an electric wire including a copper stranded wire 16 having a substantially circular cross-sectional shape and a covering layer 17 that covers the stranded wire 16. A tin plating layer is formed on the surface of the stranded wire 16 in the present embodiment. Note that a tin plating layer may not be formed on the surface of the stranded wire 16, or a plating layer made of another metal material may be formed instead of tin. Further, the stranded wire 16 may be an aluminum stranded wire, or a single wire may be used in place of the stranded wire 16 as a voltage detection wire.

As described above, the first, third to fifth power storage units 10A, 10C to 10E have the same configuration as that of the second power storage unit 10B. In the present embodiment, the voltage detection lines 15a ₁ , 15a ₂ , 15b _{2 to} 15e ₁ are connected to the electrode terminals 50a ₁ , 50c _{1 to} 50e ₁ of the first, third to fifth power storage units 10A to 10E, respectively. , 60a ₂ and 60c _{1 to} 60e ₂ . The voltage detection lines 15a ₁ , 15a ₂ , 15b _{2 to} 15e ₁ are electric wires having the same configuration as the voltage detection line 15b ₁ described above.

Further, as shown in FIG. 9, electrical insulation may be ensured by covering the electrode terminals 50 b ₁ and 60 b ₂ joined to each other with the covering members 12 and 13. 1 and 2, illustration of the covering members 12 and 13 is omitted. Specific examples of the covering members 12 and 13 include heat shrinkable tubes made of a resin material.

Similarly, although not particularly illustrated, in each of the first, third to fifth power storage units 10A, 10C to 10E, the negative electrode terminals 60a ₂ and 60c _{2 to} 60e ₂ that are bent of the second power storage device 20B, The flat positive terminals 50a ₁ , 50c _{1 to} 50e _{2 of one} power storage device 20A may be joined, and then these electrode terminals may be covered by the two covering members 11 and 12.

  And the electrical storage module 1 is comprised by the 1st-5th electrical storage unit 10A-10E being stacked mutually.

  Specifically, as shown in FIGS. 1 and 2, the second sheet portion 43 of the second power storage device 20B of the first power storage unit 10A and the first power storage device 20A of the second power storage unit 10B. 1st and 2nd electrical storage unit 10A, 10B is mutually stacked | stacked so that the 2nd sheet | seat part 43 may contact, respectively. At this time, the lead-out directions of all the electrode terminals of the first and second power storage units 10A and 10B are substantially the same.

Further, as shown in FIG. 10, the positive terminal 50a ₂ of the second power storage device 20B of the first power storage unit 10A of the lower, negative terminal of the first power storage device 20A of the upper side of the second power storage unit 10B 60b ₁ and are joined at the outside of the exterior body 40 (first and second power storage units 10A, all of the electric storage device 20A of 10B, 20B, 20A, 20B exterior body 40 of). At this time, in this embodiment, the voltage detection line 15a ₂ is interposed between the positive electrode terminal 50a ₂ of the first power storage unit 10A and the negative electrode terminal 60b ₁ of the second power storage unit 10B. 50a ₂ and 60b ₁ and the voltage detection line 15a ₂ are joined together.

Also, the positive terminal 50a ₂ of the second power storage device 20B of the first power storage unit 10A of the joined together below the negative terminal 60b of the first power storage device 20A of the upper side of the second power storage unit 10B ₁ Are folded together by the first and second folded portions 70 and 71.

The first folded portion 70 is disposed outside the exterior body 40. The first folded portion 70, in a state where the positive electrode terminal 50a ₂ and the negative terminal 60b ₁ are stacked, is formed by folding so as to reverse the front and back of the positive electrode terminal 50a ₂ and the negative terminal 60b _1. In the first folded portion 70, the positive electrode terminal 50 a ₂ and the negative electrode terminal 60 b ₁ are moved from the direction away from the outer package 40 to the direction approaching the outer package 40 (that is, with respect to the lead-out direction of the positive electrode terminal 50 a ₂ and the negative electrode terminal 60 b ₁ ). And in the opposite direction), it is folded back toward the upper second power storage unit 10B. In the first folded portion 70, main surfaces of the negative electrode terminal 60b ₁ are opposed to each other.

The second folded portion 71 is disposed outside the exterior body 40. The second folded portion 71 in a state where the positive electrode terminal 50a ₂ and the negative terminal 60b ₁ are stacked, is formed by folding so as to reverse the front and back of the positive electrode terminal 50a ₂ and the negative terminal 60b _1. In the second folded portion 71, the positive electrode terminal 50a ₂ and the negative electrode terminal 60b ₁ are separated from the outer package 40 from the direction approaching the outer package 40 (that is, with respect to the direction in which the positive electrode terminal 50a ₂ and the negative electrode terminal 60b ₁ are led out). In the same direction) toward the upper second power storage unit 10B side. Than the second folded portion 71, main surfaces of the positive electrode terminal 50a ₂ are opposed to each other.

In the present embodiment, the length L _{5 of the} portion of the folded electrode terminals 50a ₂ and 60b ₁ exposed from the exterior bodies 40 and 40 of the first and second power storage devices 20A and 20B (hereinafter simply referred to as “fifth” also the length _{L 5} "referred.) is smaller relative to at least one of the third length _{L 3} of the positive terminal second 50b ₁ of length _{L 2} and the negative electrode terminal 60a _2.

  Similarly, as shown in FIGS. 1 and 2, the second sheet portion 43 of the second power storage device 20B of the lower power storage units 10B to 10D and the first power storage device of the upper power storage units 10C to 10E. The 2nd-5th electrical storage units 10B-10E are mutually stacked so that the 2nd sheet part 43 of 20A may contact, respectively. At this time, the lead-out directions of all the electrode terminals of the second to fifth power storage units 10B to 10E are substantially the same.

Further, the positive electrode terminal _50b 2 ～50D ₂ of the second power storage device 20B of the lower of the power storage unit 10b to 10d, and the negative electrode terminal _60c 1 ～60E ₁ of the first power storage device 20A of the upper energy storage unit 10C~10E Are joined together. Furthermore, in the present embodiment, the voltage detection line _{15b 2 ~15d} 2, a positive electrode terminal _{50b 2 ~50d} 2 of the lower power storage units 10b to 10d, the negative terminal _60c of the upper energy storage unit 10C~10E ₁ ~60e 1 The electrode terminals and the voltage detection lines 15b _{2 to} 15d ₂ are joined together.

The second phase below the energy storage unit 10B~10D electric storage device 20B positive terminal _50b 2 ～50D ₂ and upper energy storage unit first of 10C~10E power storage device 20A of the negative electrode terminal _60c 1 ～60E ₁ Of these, the electrode terminals joined to each other are folded back together.

Furthermore, the positive terminal 50e ₂ of the second power storage device 20B of 10E of the fifth power storage unit located at the top, the voltage detection line 15e ₂ are joined. Similarly, the negative terminal 60a ₁ of the first power storage device 20A of 10A of the first power storage unit located at the bottom, the voltage detection line 15a ₀ are joined. The voltage detection lines 15a ₀ and 15e ₂ are electric wires having the same configuration as the voltage detection line 15a ₁ described above. In addition, the length of the part exposed from the exterior body 40 of the positive electrode terminal 50e ₂ connected to an external device (not shown) is substantially the same length as the third length L ₃ of the negative electrode terminal 60e ₂ . ing. Similarly, the length of the exposed portion of the negative electrode terminal 60a ₁ connected to the external device (not shown) from the exterior body 40 is substantially the same as the second length L ₂ of the positive electrode terminal 50a ₁ . Has been.

In addition, as shown in FIG. 10, the folded electrode terminals 50a ₂ and 60b ₁ may be covered with a covering member 11 to fix the folded shape of the electrode terminals and to ensure electrical insulation. 1 and 2, the illustration of the covering member 11 is omitted.

Specifically, as illustrated in FIG. 10, the electrode terminal 50 a ₂ is folded by the covering member 11 at the first and second folded portions 70 and 71 and stacked in a plurality (three layers in this embodiment). , 60b ₁ may be covered together. As a specific example of the covering member 11, a heat shrinkable tube made of a resin material can be exemplified as with the covering members 12 and 12.

  The covering member 11 in the present embodiment corresponds to an example of the covering member in the present invention.

  Similarly, although not particularly illustrated, the folded electrode terminals may be covered with the covering member 11 also in the two power storage units that are stacked one on the other among the second to fifth power storage units 10B to 10E.

  Next, the manufacturing method of the electrical storage module 1 demonstrated above is demonstrated, referring FIGS. 9-15 (B).

  FIG. 11 is a process diagram showing a method for manufacturing a power storage module according to an embodiment of the present invention. FIGS. 12A and 12B are diagrams showing step S30 in FIG. 11, FIG. 12A shows a state in which the electrode terminals are overlapped, and FIG. Indicates the state of FIG. 13A is a diagram illustrating step S20 in FIG. 11, illustrating a state in which the power storage units are overlaid so that the second sheet portions of the exterior body are in contact with each other, and FIG. It is a figure which shows step S30 shown to step S40, and shows the state which bend | folds the positive electrode terminal of the 2nd electrical storage device of a 2nd electrical storage unit, and has overlapped the electrode terminal. FIG. 14A is a diagram showing step S50 in FIG. 11 and shows a state in which the electrode terminals are joined. FIG. 14B is a diagram showing step S60 in FIG. Indicates the state. FIG. 15A is a view showing step S70 shown in FIG. 11, showing a state in which the bent electrode terminal is covered with a covering member, and FIG. 15B is a view showing step S80 shown in FIG. A state in which the positive electrode terminal of the second power storage device of the second power storage unit is bent is shown.

  First, in step S10 of FIG. 11, the first power storage unit 10A is formed.

Specifically, in step S11 of FIG. 11, the first power storage device 20A and the second power storage device 20B are prepared. At this time, the negative terminal 60a ₂ of the second power storage device 20B, previously formed two bent portions 62 and 63. The formation method of the two bending parts 62 and 63 is not specifically limited.

  Next, in step S12 of FIG. 11, the first and second power storage devices 20A and 20B are stacked.

Next, the second power storage device 20B is inverted with respect to the first power storage device 20A, the lead-out direction of the electrode terminals 50a ₁ and 60a ₁ of the first power storage device 20A, and the electrode terminal 50a of the second power storage device 20B. _2, the lead-out direction of 60a _2, from the substantially identical to the first and second power storage devices 20A, contacting the housing portion 421 between the 20B (see FIG. 2). Thus, the first power storage positive terminal 50a ₁ of the device 20A and the negative electrode terminal 60a ₂ of the second power storage device 20B are opposed to each other, the electrode terminals _50a 1 stranded wire 16 of the voltage detection line 15a _1, 60a ₂ is interposed.

Then, joining in step S13 of FIG. 11, the positive terminal 50a ₁ of the first power storage device 20A, the negative electrode terminal 60a ₂ of the second power storage device 20B.

Fixed Specifically, as shown in FIG. 12 (a), while interposing the stranded wire 16 of the voltage detection line 15a ₁ between the electrode terminals _50a 1, 60a _2, and the movable electrode 111 of the resistance welding machine It is sandwiched between the electrodes 112. Next, as shown in FIG. 12B, by applying a voltage between the movable electrode 111 and the fixed electrode 112, the electrode terminals 50a ₁ and 60a ₂ are joined together, and the stranded wire 16 of the voltage detection line 15a ₁ is joined. And electrode terminals 50a ₁ and 60a ₂ are joined. For example, a voltage of 220V between the movable electrode 111 and the fixed electrode 112 by applying between 4 msec, it is possible to bond the positive electrode terminal 50a ₁ to the negative terminal 60a _2.

Instead of resistance welding, the stranded wire 16 of the voltage detection wire 15a ₁ and the electrode terminals 50a ₁ and 60a ₂ may be joined by ultrasonic welding.

In the case where a coating member 12, 13 described above cover the electrode terminals _50a 1, 60a _2, in step S13, after bonding the electrode terminals _50a 1, 60a _2, the electrode terminals _50a 1, 60a ₂ coated Cover with members 12 and 13.

  10 A of 1st electrical storage units are formed through the above steps S11-S13. Similarly, 2nd-5th electrical storage unit 10B-10E is formed by performing said step S11-S13, respectively about 2nd-5th electrical storage unit 10B-10E.

Next, in step S20 of FIG. 11, the first power storage unit 10A and the second power storage unit 10B are stacked. In this case, the second sheet portion 43 of the second power storage device 20B of the first power storage unit 10A and the second sheet portion 43 of the first power storage device 20A of the second power storage unit 10B are in contact with each other. First, the first power storage unit 10A and the second power storage unit 10B are overlapped (see FIG. 13A). Moreover, the lead-out directions of all the electrode terminals 50a ₁ , 60a ₁ , 50a ₂ , 60a ₂ of the first power storage unit 10A and all the electrode terminals 50b ₁ , 60b ₁ , 50b ₂ , 60b of the second power storage unit 10B are provided. The first power storage unit 10A and the second power storage unit 10B are overlapped so that the _two lead-out directions are substantially the same.

Then, in step S30 in FIG. 11, the positive terminal 50b ₂ of the second power storage device 20B of the second power storage unit 10B which is stacked on the first power storage unit 10A, a second power storage of the first power storage unit 10A bent so as not to overlap with the negative terminal 60b ₁ of the first power storage device 20A of the positive terminal 50a ₂ and the second power storage unit 10B of the device 20B (see FIG. 13 (B)).

Then, in step S40 of FIG. 11, the positive terminal 50a ₂ of the second power storage device 20B of the first power storage unit 10A, and the negative terminal 60b ₁ of the first power storage device 20A of the second power storage unit 10B, the Overlapping each other. At this time, the positive electrode terminal 50a ₂ and the negative electrode terminal 60b ₁ are overlapped with each other with the stranded wire 16 of the voltage detection wire 15a ₂ interposed.

Then, each other at step S50 in FIG. 11, the positive terminal 50a ₂ of the second power storage device 20B of the first power storage unit 10A, and a negative terminal 60b ₁ of the first power storage device 20A of the second power storage unit 10B To join.

Specifically, as shown in FIG. 14 (A), while interposing the stranded wire 16 of the voltage detection line 15a ₂ between the electrode terminals _50a 2, 60b _1, these electrode terminals _50a 2, 60b ₁ The movable electrode 111 and the fixed electrode 112 are pressed from above and below (up and down with respect to the stacking direction of the power storage units 10A to 10E). Then, with the positive electrode terminal 50a ₂ , the voltage detection line 15a ₂ , and the negative electrode terminal 60b ₁ sandwiched between the movable electrode 111 and the fixed electrode 112 in this order, a voltage is applied between the electrodes 111 and 112, thereby The electrodes 50a ₂ and 60b ₁ superimposed on each other are joined together, and the voltage detection line 15a ₂ and the electrode terminals 50a ₂ and 60b ₁ are joined together. Instead of resistance welding, the voltage detection wire 15a ₂ and the electrode terminals 50a ₂ and 60a ₁ may be joined by the above-described ultrasonic welding.

At this time, the negative terminal first length _{L 1} of 60b ₁ is large relative to the second length _{L 2} of the positive electrode terminal 50b _1, and the fourth length _{L 4} of the positive terminal 50a ₂ by but relatively large with respect to the third length L ₃ of the negative terminal 60a _2, in joining the electrode terminals 50a _2, 60b _1, movable without interfering with the other electrode terminal arranged in the stacking direction The electrode 111 and the fixed electrode 112 can be pressed against the electrode terminals 50a2 and 60b1. Therefore, it is possible to improve the electrode terminals _50a 2, 60b ₁ bonding workability between. In particular, in this embodiment, before joining the electrode terminals 50a ₂ and 60b ₁ , the positive electrode terminal 50b ₂ of the second power storage device 20B of the second power storage unit 10B is not overlapped with the electrode terminals 50a ₂ and 60b _1. By bending the electrode terminals 50a ₂ and 60b ₁ , the movable electrode 111 and the fixed electrode 112 can be easily pressed, and the joining workability between the electrode terminals 50a ₂ and 60b ₁ can be further improved.

Next, in step S <b> 60 of FIG. 11, the electrode terminals 50 a ₂ and 60 b ₁ joined to each other are folded back by the first folding unit 70 and folded by the second folding unit 71. In this case, from the viewpoint of suppressing disconnection or breakage of the voltage detection line 15a _2, the positive electrode terminal _50a 2 except joint portion of the positive electrode terminal _50a joined to each other 2, 60b _1, folded back 60b ₁ (i.e., the first and The second folded portions 70 and 71 are arranged at portions other than the joint portions of the positive terminals 50a ₂ and 60b ₁ ).

The order of folding back the electrode terminals 50a ₂ and 60b ₁ joined to each other may be such that the first folded portion 70 may be folded first, or the second folded portion 71 may be folded first. In this step S60, a fifth length _{L 5} of the folded electrode terminals 50a2,60b1 the second third of the negative terminal 60a ₂ of the electric storage device 20B of a length _{L 3} and the first power storage unit 10A Electrode terminals 50a ₂ joined to each other so as to be relatively short with respect to at least _one of the second lengths L ₂ of the positive electrode terminal 50b ₁ of the _first electricity storage device 20A of the second electricity storage unit 10B, 60b ₁ is folded.

Thus, by folding back the electrode terminals 50a ₂ and 60b ₁ joined to each other, the electrode terminals 50a ₂ and 60b ₁ protrude from the sides of the first and second power storage units 10A and 10B. Therefore, the electrode terminals 50a2 and 60b1 can be prevented from unintentionally coming into contact with other electrode terminals. Thereby, the short circuit of electrode terminals can be suppressed. Further, the power storage module 1 can be downsized.

In particular, in the present embodiment, the fifth length L ₅ of the folded electrode terminals 50a ₂ and 60b ₁ is the same as the second length L ₂ of the positive electrode terminal 50b ₁ and the third length of the negative electrode terminal 60a ₂ . Since the electrode terminals 50a ₂ and 60b ₁ do not protrude to the side of the first and second power storage units 10A and 10B by shortening relative to at least one of L ₃ , the electrode terminals can be more reliably While short circuiting can be suppressed, the electrical storage module 1 can be more downsized more reliably.

Next, in step S <b> 70 of FIG. 11, the folded electrode terminals 50 a ₂ and 60 b ₁ are covered with the covering member 11. At this time, by covering the electrode terminals 50a ₂ and 60b ₁ which are folded and laminated in three layers, the covering member 11 is arranged so that the folded electrode terminals 50a ₂ and 60b ₁ return to their original shapes. While preventing spreading, it can suppress that it short-circuits between other electrode terminals.

Then, in step S80 of FIG. 11, the positive terminal 50b ₂ by bending at step S30, bent again to return to its original shape.

  The steps S20 to S80 of FIG. 15 described above are repeated for the second to fifth power storage units 10B to 10E, so that the first to fifth power storage units 10A to 10E are stacked on each other and the first The fifth power storage units 10A to 10E are electrically connected in series, and the power storage module 1 is assembled.

  Step S20 in FIG. 11 in the present embodiment corresponds to an example of a fourth process in the present invention, and step S30 in FIG. 11 in the present embodiment corresponds to an example of a fifth process in the present invention. Step S40 in FIG. 11 corresponds to an example of the first step in the present invention, step S50 in FIG. 11 in the present embodiment corresponds to an example of the second step in the present invention, and step in FIG. 11 in the present embodiment. S60 corresponds to an example of the third step in the present invention, and step S70 in FIG. 11 in the present embodiment corresponds to an example of the sixth step in the present invention.

  The embodiment described above is described for facilitating the understanding of the present invention, and is not described for limiting the present invention. Therefore, each element disclosed in the above embodiment is intended to include all design changes and equivalents belonging to the technical scope of the present invention.

In the above-described embodiment, the power storage devices 20A and 20B are led out in the same direction by the pair of electrode terminals 50a ₁ and 60a ₁ (50a ₂ and 60a ₂ ), and the exterior body 40 is convex only on one side. However, the type of the electricity storage device is not particularly limited to this.

  For example, the type of the electricity storage device may be a type in which the pair of electrode terminals are led out in opposite directions and the exterior body has a convex accommodating portion only on one side. Alternatively, the type of the electricity storage device may be a type in which the pair of electrode terminals are led out in the same direction and the exterior body has convex accommodating portions on both sides. Alternatively, the type of the electricity storage device may be a type in which the pair of electrode terminals are led out in opposite directions and the exterior body has convex accommodating portions on both sides.

  In the above-described embodiment, the negative electrode terminal of the first electricity storage device 20A and the positive electrode terminal of the second electricity storage device 20B are joined (that is, electrode terminals of different electrodes among the electrode terminals are joined). However, it is not particularly limited to this, for example, the negative electrode terminal of the first power storage device 20A and the positive electrode terminal of the second power storage device 20B are joined (that is, the electrode terminals having the same polarity among the electrode terminals are joined together). ) Or you may join the positive electrode terminal of 20 A of 1st electrical storage devices, and the positive electrode terminal of 2nd electrical storage device 20B.

1 ... storage module 10A to 10E ... first to fifth energy storage unit 11 - 13 ... cover member _{15a 0, 15a 1 ~15e 1,} 15a 2 ~15e 2 ... voltage detection line 16 ... stranded wire 17 ... coating layer 20A, 20B ... 1st, 2nd electrical storage device 30 ... Electrode laminated body 31 ... Positive electrode plate 311 ... Positive electrode collector
312 ... Main unit
Reference numeral 313: Lead portion 314: Positive electrode layer 32: Negative electrode plate 321: Negative electrode current collector
322 ... Main unit
323 ... Lead portion 324 ... Negative electrode layer 33 ... Separator 34 ... Lithium electrode 341 ... Lithium electrode current collector
342 ... Main unit
343 ... Lead portion 344 ... Lithium layer 40 ... Exterior body 41 ... Laminate film
41a ... metal foil
41b ... 1st resin film
41c: second resin film 42: first seat portion 421 ... receiving portion 422 ... flange portion 43 ... second sheet portion 44 ... bent portion 45 ... short sides 50a ₁ ～50E 2 _... positive terminal 501 ... rear end 502 ... tip portion 51 ... sealant resin layer 60a _{1 to} 60e ₂ ... negative electrode terminal 601 ... rear end portion 602 ... tip portion 61 ... sealant resin layer 62 ... first bent portion 63 ... second bent portion 70 ... first 1 folded portion 71 ... second folded portion 111 ... movable electrode 112 ... fixed electrode

[1] A method for manufacturing a power storage module according to the present invention is a method for manufacturing a power storage module including first and second power storage devices in which an electrode stack is accommodated in an outer package, wherein the first power storage device is the said electrode stack of the first power storage device with are electrically connected, with the first of the first and second electrode pin the is drawn from the exterior of the electric storage device, wherein The second power storage device is electrically connected to the electrode stack of the second power storage device, and third and fourth powers drawn from the exterior body of the second power storage device. comprising a terminal, said power storage module includes a wire for voltage detection of the plurality of power storage devices, a manufacturing method of the power storage module, the axial direction of the electric wire of the first electrode terminal and the fourth electrode Terminal While interposing the electrical wire along a direction out come, a first step of superimposing the first electrode terminal and the fourth electrode terminal to each other, said first electrode being superimposed on each other A second step of partially joining the terminal, the fourth electrode terminal, and the electric wire to each other at a joint portion; and the first electrode terminal and the fourth electrode terminal joined to each other. And a third step of folding back at a portion other than the joining portion .

[5] In the above invention, the third step is partially joined with the joint portion of the tip portion of the mutually superposed et a first electrode terminal and the fourth electrode terminal, the it may include returning Ri folded from the joint portion at the base end side.

[7] The power storage module according to the present invention includes first and second power storage devices in which an electrode stack is accommodated in an exterior body, and electric wires for voltage detection of the power storage device, and the first power storage device includes: The first and second power supplies that are electrically connected to the electrode stack of the first power storage device and are drawn out in substantially the same direction from the exterior body of the first power storage device. comprising a terminal, said second power storage device, first with and is electrically connected to the electrode stack of the second power storage device, is drawn from the outer body of said second power storage device 3 and a fourth electrode pin, prior Symbol first power storage device is stacked on the second power storage device, and the first electrode terminal and the fourth electrode terminal, the electric wire The axial direction of the first electrode end And the fourth state in which the drawer has the electrical wire is interposed along the direction of the electrode terminal is bonded to the partially cross at junction, the said joined to one another first electrode terminal The fourth electrode terminal is a power storage module that is folded at a portion other than the joint portion .
[8] In the above invention, the first electrode terminal, the fourth electrode terminal, and the electric wire are partially at the joint portion of the first electrode terminal and the tip end portion of the fourth electrode terminal. They may be joined to each other and folded back at the base end side from the joint portion.

Claims (7)

A method of manufacturing a power storage module including first and second power storage devices in which an electrode stack is accommodated in an exterior body,
The first power storage device is electrically connected to the electrode stack of the first power storage device and is pulled out from the exterior body of the first power storage device. An electrode terminal,
The second power storage device is electrically connected to the electrode stack of the second power storage device and is pulled out from the exterior body of the second power storage device. An electrode terminal,
The method for manufacturing the power storage module includes:
A first step of overlapping the first electrode terminal and the fourth electrode terminal with each other;
A second step of joining the first electrode terminal and the fourth electrode terminal stacked on each other;
And a third step of turning back the first electrode terminal and the fourth electrode terminal joined to each other. It is a manufacturing method of the electrical storage module according to claim 1,
The first and second electrode terminals are drawn out in substantially the same direction from the exterior body of the first power storage device,
The third and fourth electrode terminals are drawn out in substantially the same direction from the exterior body of the second electricity storage device,
The first length of the portion of the first electrode terminal exposed from the exterior body of the first electricity storage device is the portion of the second electrode terminal exposed from the exterior body of the first electricity storage device. Relatively large with respect to the second length of
The fourth length of the portion of the fourth electrode terminal exposed from the exterior body of the second electricity storage device is the portion of the third electrode terminal exposed from the exterior body of the second electricity storage device. Relatively large with respect to the third length of
In the third step, the lengths of the portions of the folded first electrode terminal and the fourth electrode terminal exposed from the exterior body of the first and second power storage devices are the second A power storage module including folding back the first electrode terminal and the fourth electrode terminal that are joined to each other so as to be relatively small with respect to at least one of the length of the third length and the third length Manufacturing method. It is a manufacturing method of the electrical storage module according to claim 2,
The power storage module further includes a plurality of electric wires for voltage detection of the power storage device,
The first step includes overlapping the first electrode terminal and the fourth electrode terminal with the electric wire interposed therebetween,
The method for manufacturing a power storage module, wherein the second step includes collectively joining the fourth electrode terminal, the electric wire, and the first electrode terminal. It is a manufacturing method of the electrical storage module according to claim 2 or 3,
The power storage module includes a plurality of power storage units including the first and second power storage devices,
The exterior body is
A first sheet portion having a convex accommodating portion that wraps the electrode laminate;
A second sheet portion that is substantially flat and on which the first sheet portion is stacked via the electrode laminate,
The first and second power storage devices of the power storage unit are stacked on top of each other so that the housing portions are in contact with each other,
The second electrode terminal of the power storage unit is joined to the third electrode terminal of the power storage unit;
The method for manufacturing the power storage module includes:
Before the first step, a fourth step of stacking the plurality of power storage units so that the second sheet portions are in contact with each other;
After the fourth step and before the second step, the fourth electrode terminal in the other power storage unit stacked on the second power storage device of the power storage unit is connected to the power storage unit. A fifth step of bending the fourth electrode terminal and the first electrode terminal of the other power storage unit so as not to overlap each other.
The first step is a method for manufacturing a power storage module, wherein the fourth electrode terminal in the power storage unit and the first electrode terminal in another power storage unit are overlapped with each other. It is a manufacturing method of the electrical storage module according to any one of claims 2 to 4,
The method for manufacturing a power storage module, wherein the third step includes turning back a portion other than a joint portion between the first electrode terminal and the fourth electrode terminal joined to each other. It is a manufacturing method of the electrical storage module according to any one of claims 2 to 5,
The manufacturing method of the electrical storage module further provided with the 6th process of covering the said 1st electrode terminal and said 4th electrode terminal which were turned back by a coating | coated member after the said 3rd process. A power storage module including first and second power storage devices in which an electrode stack is accommodated in an exterior body,
The first power storage device is electrically connected to the electrode stack of the first power storage device and pulled out from the exterior body of the first power storage device in substantially the same direction. And first and second electrode terminals,
The second power storage device is electrically connected to the electrode stack of the second power storage device and is pulled out from the exterior body of the second power storage device. An electrode terminal,
The first length of the portion of the first electrode terminal exposed from the exterior body of the first electricity storage device is the portion of the second electrode terminal exposed from the exterior body of the first electricity storage device. Relatively large with respect to the second length of
The fourth length of the portion of the fourth electrode terminal exposed from the exterior body of the second electricity storage device is the portion of the third electrode terminal exposed from the exterior body of the second electricity storage device. Relatively large with respect to the third length of
The first power storage device is stacked on the second power storage device,
The first electrode terminal and the fourth electrode terminal are bonded to each other,
The first electrode terminal and the fourth electrode terminal joined to each other are folded,
The lengths of the portions of the first and second electrode terminals that are folded back and exposed from the exterior body of the first and second power storage devices are the second length and the third length. An electrical storage module that is relatively small with respect to at least one of the lengths of the two.

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