KR102291005B1 - Method for producing anode material for secondary battery - Google Patents

Abstract

The present invention relates to a method for manufacturing an anode material for a secondary battery, comprising the steps of exchanging alkali metals in water glass with hydrogen ions; drying the ion exchanged compound; and reducing the dried compound to form an _{SiO x compound.}

Description

Method for producing anode material for secondary battery {Method for producing anode material for secondary battery}

The present invention relates to a method for manufacturing a negative electrode material for a secondary battery.

Lithium-ion secondary batteries are being applied to various applications such as portable power sources, electric vehicles, and power storage. Carbon-based materials are mainly used as anode materials for lithium ion secondary batteries, and graphite is the most widely used among them. Lithium is stored between the layers of graphite, and electrons injected with lithium are stored in carbon. Recently, as batteries of higher capacity are required, research on high-capacity negative electrode materials is being conducted. Among them, alloys that can be charged through Li-alloying reactions with lithium such as Si, Ge, Sn, Al, etc. Alloy type anode materials are receiving the most attention.

However, in the case of, for example, a silicon (Si)-based negative electrode among lithium alloying materials that alloy with lithium, due to a large volume change of about 400% or more during charging and discharging when reacting with lithium, lifespan characteristics There was a problem that this significantly lowered. In order to overcome this problem, a _{method of using an SiO x-} based negative active material has been proposed, but there is a problem that the manufacturing cost is high.

An object of the present invention is to provide a method of manufacturing an anode material for a secondary battery that can improve life characteristics by not only realizing a high-capacity anode material through spray drying using a low-priced water glass material, but also controlling a uniform volume expansion behavior. will be.

In order to achieve the above object, the present invention comprises the steps of exchanging M in the compound of Formula 1 with a hydrogen ion; drying the ion exchanged compound; and reducing the dried compound to form a compound of Formula 2 provides a method of manufacturing a negative electrode material for a secondary battery.

[Formula 1]

mM ₂ O·nSiO ₂ ·yH ₂ O

[Formula 2]

SiO _x

In Formula 1, M is an alkali metal, m, n, and y are each independently 1 to 10, and in Formula 2, x is 1 to 2.

In the present invention, M may be Li, Na or K.

In the present invention, the ion exchange step may be performed using a cation exchange resin for the compound of Formula 1 in an aqueous solution state.

In the present invention, the drying step may be performed using a spray drying method.

In the present invention, the reduction step is performed using a reducing agent and a scavenger, and the weight ratio of the dried compound, the reducing agent, and the scavenger may be 1:0.7 to 1.3:0.5 to 1.5.

In the present invention, the reducing agent may be Mg, and the scavenger may be NaCl.

The method according to the invention may further comprise a step of removing the reducing agent in oxidized form after the reducing step.

The method according to the present invention may further include the step of forming a carbon coating layer on the compound of formula (2).

In the present invention, the carbon coating layer may be formed by carbonizing a carbon precursor after coating it on the compound of formula (2).

In the present invention, the carbon precursor may be a dopamine monomer or a polymer.

The present invention may satisfy Equation (1).

[Equation 1]

(C _D1 /C _C1 )×100 > 62

In Equation 1, C _D1 is the discharge capacity in the first cycle of the secondary battery to which the negative electrode material is applied, and C _C1 is the charge capacity in the first cycle of the secondary battery to which the negative electrode material is applied.

According to the present invention, it is possible to obtain an anode active material with low-cost water glass, and uniform volume expansion behavior can be controlled, thereby exhibiting improved electrochemical properties of lifespan. In addition, it is possible to synthesize an anode material with improved electrochemical properties of the material through spray drying, and it has an advantage in applying the anode material for medium and large-sized batteries at a lower material price than the existing anode material, so the commercialization possibility will be high.

1 shows a SiO _x material synthesis process using water glass, and includes a scanning electron microscope (SEM) image with or without ion exchange.
Figure 2 shows the reduction of _{SiO z material Mg using water glass.}
Figure 3 shows the X-ray diffraction (XRD) analysis results according to the weight ratio _{of SiO z , Mg and NaCl.}
Figure 4 shows the SiO _x anode material carbon coating.
5 shows the voltage profile of _{SiO x} @C using water glass.
6 shows the lifetime characteristics of _{SiO x} @C using water glass.

Hereinafter, the present invention will be described in detail.

The method for manufacturing a negative electrode material for a secondary battery according to the present invention may include an ion exchange step, a drying step, a reduction step, and the like.

First, in the ion step, M of the compound of Formula 1 is exchanged for a hydrogen ion.

[Formula 1]

mM ₂ O·nSiO ₂ ·yH ₂ O

In Formula 1, M is an alkali metal, and m, n, and y are each independently 1 to 10.

The present invention is characterized in that water glass is used in the manufacture of the anode material. Water glass may mean an alkali silicate obtained by melting silicon dioxide and alkali or an aqueous solution thereof, for example, mLi ₂ O·nSiO ₂ , mNa ₂ O·nSiO ₂ , mK ₂ O·nSiO ₂ It can mean an aqueous solution, and when expressed by a chemical formula containing water, it can be expressed as mLi ₂ O·nSiO ₂ ·yH ₂ O, mNa ₂ O·nSiO ₂ ·yH ₂ O, mK ₂ O·nSiO ₂ ·yH ₂ O have. In this case, m may be 1 to 10, preferably 1 to 5, more preferably 1 to 2. n may be 1 to 10, preferably 1 to 7, more preferably 2 to 4. y may be 1 to 10, preferably 1 to 5, more preferably 1 to 2. Since water glass is inexpensive, the manufacturing cost of the anode material can be lowered.

M in Formula 1 may be an alkali metal, for example, Li (lithium), Na (sodium) or K (potassium), preferably Li (lithium). The molar ratio (n/m) of SiO ₂ to M ₂ O may be 1 to 4, preferably 1.6 to 3.6, and more preferably 2 to 3.

The content of M ₂ O in the water glass may be 5 to 50 wt% based on the total weight of the water glass. The content of SiO _{2 in} the water glass may be 20 to 85 wt% based on the total weight of the water glass. The content of water (H ₂ O) in the water glass may be 10 to 30 wt% based on the total weight of the water glass. The water glass may also contain small amounts of other components (such as iron oxide). Water glass can be used by diluting it to an appropriate concentration.

In the ion exchange step, that is, in the step of exchanging alkali metal ions in the alkali silicate for hydrogen ions, M in Formula 1 may be exchanged for hydrogen ions. The exchange rate may be, for example, greater than or equal to 90%. The exchange step may be performed, for example, through an ion exchange means such as an ion exchange resin. The ion exchange resin means an insoluble synthetic resin having ions capable of performing ion exchange, and for example, may be a resin in which an ion exchange group is covalently bonded to a resin having a three-dimensional network structure. Examples of the ion-exchange group include an acid group such as a sulfone (acid) group, a carboxy group, and a phenolic hydroxyl group; Basic groups such as an amino group, an exchanged amino group, and a quaternary ammonium group can be exemplified.

As the ion exchange resin, a cation exchange resin or an acidic ion exchange resin may be used. Specifically, a cation exchange resin using a sulfonic acid group as an ion exchange group and a hybrid polymer of styrene and divinylbenzene or a hybrid polymer of methacrylic acid and divinylbenzene as a parent may be used.

The ion exchange step may be performed by passing the water glass through a column filled with the ion exchange resin at an appropriate speed using a pump or the like. _{Through the ion exchange step, the water glass is converted to an aqueous SiO z} solution with complete or near exchange of alkali metals in the water glass to hydrogen, wherein z is 1 to 10, preferably 1.3 to 4, more preferably 1.5 to 2 can be This z value is larger than the x value which will be described later.

Referring to FIG. 1 , when ion exchange is not performed, SiO _x ·Mg ₂ SiO ₄ or Li ₂ O·SiO _x particles are formed, and when ion exchange is performed according to the present invention, SiO _x particles are formed.

In addition, the method according to the present invention may further include the step of adjusting the pH of _{the SiO z aqueous solution formed through the exchange step.} For example, the pH adjustment step _{may be performed by adding NH 4} OH or the like to the _{SiO z} aqueous solution. The pH of the SiO _z aqueous solution may be adjusted to 2 to 5, preferably 3 to 4.

Next, the ion-exchanged compound is dried. By evaporation of water through drying, it can be obtained the water is removed from the SiO _z SiO _z aqueous solution. The drying step may be performed using a spray drying method (apparatus). Spray drying (spray drying) is a method in which droplets of liquid atomized by an atomizer are instantly dried and powdered by contact with heating air (hot air). For example, spray drying conditions may be a nozzle diameter of 0.02 to 5 mm, a spray rate of 0.1 to 1 m 2 /min, an atomizer pressure of 100 to 300 kPa, a temperature of 100 to 250° C., and a time of 1 to 5 hours. Through spray drying, hollow spherical particles can be obtained. The average particle size may be 1 to 10 μm, preferably 2 to 5 μm. By appropriately controlling the drying conditions, the shape and size of the particles can be appropriately controlled.

Then, the dried compound is reduced to form the compound of formula (2). As shown in FIG. 2 , porous particles in the shape of a donut can be obtained through reduction.

[Formula 2]

SiO _x

In formula (2), x is 1 to 2, preferably 1.1 to 1.5, more preferably 1.2 to 1.4. Through reduction, the value of x becomes smaller than the value of z.

The reduction step is performed using a reducing agent and a scavenger, but the _{weight ratio of the dried compound (SiO z} powder), the reducing agent and the scavenger is 1:0.7-1.3:0.5-1.5, preferably 1:0.8 -1.2:0.7-1.3, more preferably 1:0.9-1.1:0.9-1.1, most preferably 1:1:1. Referring to FIG. 3 , _{a high purity compound of Formula 2 may be obtained by suppressing the generation of impurities such as Mg 2} SiO ₄ within the above-described range, and outside the above-described range, the above-described effect cannot be obtained.

The reducing agent may be a metal, particularly a metal in powder form, preferably Mg powder. The reaction when using Mg as a reducing agent is as follows.

[Scheme 1]

SiO _z + Mg → SiO _x + MgO

The scavenger may be a salt, in particular a salt in powder form, preferably NaCl powder. NaCl can suppress the production of _{Mg 2} SiO ₄ and the like by acting as a scavenger. Referring to FIG. 1 , when only Mg is used for reduction without ion exchange, SiO _x ·Mg ₂ SiO ₄ particles are formed, but when NaCl is added during reduction, Li ₂ O·SiO _x particles are formed. That is, it is preferable to add NaCl to the reduction process to suppress the generation of _{Mg 2} SiO _{4 material.}

The reduction step may be performed at a temperature of 600 to 700° C. for 2 to 4 hours after mixing the _{SiO z powder, the reducing agent powder and the scavenger powder.} In addition, the reduction reaction may be performed in an argon/hydrogen (Ar/H ₂ ) atmosphere. The argon flow rate may be 150 to 250 sccm (cm 3 /min), and the hydrogen flow rate may be 20 to 30 sccm.

The method according to the invention may further comprise a step of removing the reducing agent in oxidized form after the reducing step. For example, when an Mg reducing agent is used as shown in Scheme 1, MgO may be removed. The removal (etching) method may be performed using an acid (such as hydrochloric acid).

In addition, the method according to the present invention may further include the step of forming a carbon coating layer on the compound of formula (2). By forming the carbon coating layer, _{the conductivity of SiO x} can be improved. The carbon coating layer may be formed by coating a carbon precursor on the compound of Formula 2 and then carbonizing it. As the carbon precursor, a dopamine monomer, a dopamine polymer (polydopamine), or the like may be used. As shown in Figure 4, carbonization can be divided into primary carbonization and secondary carbonization, specifically, in the first carbonization step, after raising the temperature to 350 to 450 °C at a temperature increase rate of 0.5 to 1.5 °C / min in a nitrogen atmosphere It can be maintained for 1 to 3 hours, and in the second carbonization step, after raising the temperature to 750 to 850 °C at a temperature increase rate of 4 to 6 °C/min in a nitrogen atmosphere, it can be maintained for 2 to 4 hours. Primary carbonization and secondary carbonization may be performed continuously.

In addition, the method according to the present invention may further include the step of electrospinning using _{SiO x particles.} Electrospinning can be performed using a conventional electrospinning apparatus. In the electrospinning step, SiO _x particles and a polymer solution may be mixed and then electrospun. For example, _{30 to 70% by weight of the SiO x} particles and 30 to 70% by weight of the polymer solution may be mixed. The polymer solution may include a polymer and a solvent. As the polymer, a conductive polymer such as polyacrylonitrile (PAN) may be used. As a solvent, ethanol etc. can be used. The concentration of the polymer in the polymer solution may be, for example, 1 to 50% by weight. It is possible to form a one-dimensional nanostructure containing _{SiO x} through electrospinning.

On the other hand, after UV-ozone treatment on the current collector, electrospinning may be performed to form a negative electrode material. When the current collector is subjected to UV-ozone treatment, the binding force between the current collector and the electrode material can be improved. Accordingly, it is possible to suppress the desorption phenomenon of the electrode material from the current collector generated during the operation of the battery, and to improve the lifespan characteristics of the secondary battery.

The carbon-coated SiO _x particles prepared as described above may be usefully used as an anode active material. In the prepared SiO _x particles, alkali metals such as Li and reducing agents such as Mg may not exist at all or may be present in very small amounts.

The present invention may satisfy Equation (1).

[Equation 1]

(C _D1 /C _C1 )×100 > 62

In Equation 1, C _D1 is the discharge capacity in the first cycle of the secondary battery to which the negative electrode material is applied, and C _C1 is the charge capacity in the first cycle of the secondary battery to which the negative electrode material is applied.

Equation 1 may mean coulombic efficiency, and may preferably be 65% or more. The upper limit may be 90%, 80% or 70%. _{The SiO x} particles prepared according to the present invention can prevent a decrease in initial efficiency due to the formation of _{Li 2 O and the like.}

The negative electrode material prepared according to the present invention can be applied to a secondary battery, particularly a lithium secondary battery. A lithium secondary battery may include a positive electrode, a negative electrode, an electrolyte, and a separator.

The negative electrode may be composed of a negative electrode current collector and a negative electrode layer, and the negative electrode may generate and consume electrons by an electrochemical reaction, and may serve to provide electrons to an external circuit through the current collector.

The negative electrode layer may include an anode active material, a conductive material, a binder, and the like, and disperse and mix them in a dispersion medium (solvent) to make a slurry, and then coat the slurry on a current collector to prepare an anode. _{As the negative electrode active material, SiO x} particles prepared according to the method of the present invention described above may be used. Carbon black or the like can be used as the conductive material. Polyacrylic acid (PAA) or the like may be used as the binder. A weight ratio of the anode active material, the conductive material, and the binder may be 70:10 to 30:5 to 15.

The negative electrode current collector is not particularly limited as long as it has conductivity without causing chemical change during charging and discharging, and for example, steel, aluminum, copper, nickel, titanium, calcined carbon, or carbon on the surface of aluminum or stainless steel. , nickel, titanium, silver or the like surface-treated may be used.

The positive electrode current collector is not particularly limited as long as it has high conductivity without causing chemical change in the battery, and for example, stainless steel, aluminum, nickel, titanium, fired carbon, or carbon on the surface of aluminum or stainless steel; Those surface-treated with nickel, titanium, silver, etc. may be used. The positive electrode current collector may increase the adhesion of the positive electrode active material by forming fine irregularities on the surface thereof, and may be formed in various forms such as a film, a sheet, a foil, a net, a porous body, a foam, a nonwoven body, and the like.

Examples of the positive electrode active material _{include a layered compound such as lithium cobalt oxide (LiCoO 2} ) and lithium nickel oxide (LiNiO ₂ ), or a compound exchanged with one or more transition metals; Formula _{Li 1 + x Mn 2 - x} O 4 ( where, x is from 0 to 0.33), LiMnO _3, the lithium manganese oxide such as LiMn ₂ O _3, LiMnO _2; lithium copper oxide (Li ₂ CuO ₂ ); vanadium oxides such as LiV ₃ O ₈ , V ₂ O ₅ , and Cu ₂ V ₂ O _{7 ;} Ni site-type lithium nickel oxide represented by the formula LiNi _{1 - x} M _x O ₂ (here, M=Co, Mn, Al, Cu, Fe, Mg, B or Ga, and x=0.01 to 0.3); Formula LiMn _{2 - x} M _x O ₂ (where M=Co, Ni, Fe, Cr, Zn or Ta and x=0.01 to 0.1) or Li ₂ Mn ₃ MO ₈ (where M=Fe, Co, Ni) , Cu or Zn) represented by lithium manganese composite oxide; _{LiMn 2} O ₄ disulfide compounds in which a part of Li in the formula is exchanged for alkaline earth metal ions; And the like Fe ₂ (MoO _{4) 3,} but is not limited to these.

The separator is a member that separates the anode and the cathode so that they do not come into direct contact and short circuit. The separator not only separates the positive and negative electrodes, but also plays an important role in improving stability. The separator may be formed of at least one of polypropylene and polyethylene.

The electrolyte serves as a medium for transporting lithium ions between the positive and negative electrodes, and an electrolyte in which a lithium salt is dissolved in an organic solvent may be used. As the electrolytic solution, a lithium salt-containing non-aqueous electrolytic solution can be used. The non-aqueous electrolyte preferably contains a carbonate-based compound to prevent corrosion of the metal member. Examples of carbonate compounds include cyclic carbonates including ethylene carbonate (EC) and propylene carbonate (PC), diethyl carbonate (DEC), dimethyl carbonate (DMC), ethylmethyl carbonate (EMC), and dipropyl carbonate (DPC). Linear carbonate, dimethylsulfoxide, acetonitrile, dimethoxyethane, diethoxyethane, tetrahydrofuran, N-methyl-2-pyrrolidone (NMP), methyl propionate, ethyl propionate, propyl propionate and a single substance or a mixture of two or more selected from gamma butyrolactone (GBL). _{LiPF 6} or the like can be used as the lithium salt. Fluoroethylene carbonate (FEC) may be added to the electrolyte.

The organic solvent is ethylene carbonate, propylene carbonate, diethyl carbonate, dimethyl carbonate, 1,2-dimethoxyethane, 1,2-diethoxyethane, gamma-butyrolactone, tetrahydrofuran, 2-methyltetrahydrofuran, 1 It may include at least one of ,3-dioxene, 4-methyl-1,3-dioxene, diethyl ether, sulfolane, ethylmethyl carbonate, and butyronitrile.

In the present invention, a high-capacity SiO _x anode material for a secondary battery can be manufactured using a low-cost water glass material. _{Water glass can be synthesized into a spherical LiO 2} -SiO ₂ composite by using a spray drying method, but preferably, water glass is ion-exchanged through an ion exchange resin according to the present invention, and then the water glass is converted into a spherical SiO 2 composite by spray drying. It can be synthesized with _{2 materials.} Then, the anode active material can be synthesized by reducing the material and removing impurities using magnesium. An anode active material can be obtained with low-cost water glass, and a uniform volume expansion behavior can be controlled, thereby exhibiting improved lifespan electrochemical properties. In this way, it is possible to synthesize a silica material by spray-drying a water glass material, and to synthesize a high-capacity negative active material having a stable lifespan through Mg reduction.

The present invention can be applied to a negative electrode material of a lithium ion battery. In addition, it can be applied to the anode material related field of the electrochemical energy storage system that converts and stores electrical energy into chemical energy by charging lithium ions, and obtains the necessary electrical energy again through discharging the lithium stored as chemical energy when energy is needed. have. In addition, it can be applied to a material synthesis field capable of synthesizing a large amount of anode SiO _{x material at low cost.} In addition, it can be applied to a large-capacity battery system, in particular, a large-capacity battery system such as an electric vehicle or ESS (Energy Storage System) that needs to store and release a large amount of energy in a limited space. In addition, it can be applied to the power supply and demand management system, in particular, the power supply and demand management system corresponding to the peak power without the need for an additional generator by using the energy stored in the power peak time after storing the energy during the remaining power time. In addition, by producing a low-cost, high-capacity negative electrode active material, it can be applied to the negative electrode material of small and medium-sized batteries such as small secondary batteries, secondary batteries for electric vehicles, and storage systems of power generation complexes. In addition, it can be applied to anode materials of medium and large-sized battery systems and ESS systems.

The present invention is specifically illustrated by way of examples below, but the scope of the present invention is not limited by the examples.

[Example]

As water glass, Li ₂ O·nSiO ₂ ·yH ₂ O (n is about 3, y is about 1) was placed in a column filled with an ion exchange resin (resin total exchange capacity of 1.8 meq/ml, functional group sulfonic acid, column Φ26*(t) 2.0 * 500 mm), Li was ion exchanged with H _{to obtain an aqueous solution of SiO z} (z is about 2).

Next, the SiO _z aqueous solution was dried using a spray drying device to obtain donut-shaped porous spherical SiO _z particles having an average particle diameter of 2 to 5 μm. Spray drying conditions were a nozzle diameter of 0.5 mm, an atomizer pressure of 250 kPa, a spraying speed of 0.47 m 2 /min, a temperature of 150° C., and a time of 3 hours.

Then, the dried compound was reduced to obtain SiO _x (x is about 1.3) particles. Mg powder was used as a _{reducing agent and NaCl powder as a scavenger. The weight ratio of SiO z} powder, reducing agent and scavenger was 1:1:1. After mixing each powder, the reduction step was performed at a temperature of 650° C. for 3 hours under an _{Ar/H 2} atmosphere (Ar flow rate: 200 sccm, H _{2 flow rate: 25 sccm).} After the reduction reaction, MgO was removed using hydrochloric acid.

Next, SiO _x particles were coated with dopamine and then carbonized to form a carbon coating layer. In the first carbonization step, the temperature was raised to 400° C. in a nitrogen atmosphere at a temperature increase rate of 1° C./min and maintained for 2 hours, and in the second carbonization step, the temperature was raised to 800° C. at a temperature increase rate of 5° C./min in a nitrogen atmosphere. It was maintained for 3 hours.

[Comparative example]

Except that the ion exchange step was not performed, it was carried out in the same manner as in Example.

[Test Example]

_{Electrochemical properties of SiO x} anode material according to the presence or absence of residual lithium ions in the case where ion exchange is not performed or not, in order to confirm the change in the electrochemical properties _{of the SiO x} material due to the residual lithium ions inside the water glass were comparatively analyzed. Evaluation of the synthesized SiO _x anode materials was performed by manufacturing an electrode after carbon coating using dopamine.

Specifically, the embodiment and the comparative example SiO _x particulate Li ₂ O and SiO _x particles was produced in the lithium battery using a negative electrode active material. The negative electrode layer was composed of a negative electrode active material, a conductive material (carbon black), and a binder (PAA, 35%) in a weight ratio of 70:20:10. As the electrolyte, _{an EC/DEC mixture containing 1.3 M LiPF 6} (volume ratio 3:7, FEC 5% addition) was used. After measuring the charging capacity, discharging capacity, coulombic efficiency, and discharging capacity retention rate after 60 cycles in the first cycle, the results are shown in Table 1.

0.2C@
1 ^st cycle Charge
(mAh/g) Discharge
(mAh/g) Efficiency
(%) Maintain@
60cycle (%) Without ion exchange 2240 1383 61.7 89.0 With ion exchange 1681 1099 65.4 75.3

Referring to FIG. 3 , when _{only SiO z} and Mg are used _{without NaCl addition during reduction (SiO z} : Mg = 1: 0.8), impurities such as _{Mg 2} SiO _{4 are generated.} SiO _z : Mg: NaCl = 1: 0.5: In the case of 1: Mg content was insufficient, the Si peak was not well revealed. SiO _z In the case of : Mg : NaCl = 1 : 1 : 1, only a long and sharp Si peak existed. FIGS. 5 and 6 _{show the electrochemical characteristics of SiO x} @C using water glass. In FIG. 6 , the capacity is the charging capacity. The capacity in the case of performing ion exchange was lower than the capacity in the case in which ion exchange was not performed, but the important initial efficiency in the lithium battery was higher when the ion exchange was performed.

If ion exchange is not performed, the initial efficiency decreases due to an irreversible reaction with _{Li 2 O contained in the water glass.} As shown in the upper drawing of FIG. 4 , _{when Li 2} O is present in the _{synthesized SiO x} negative electrode material _{, an active/inactive composite is formed with SiO x} , thereby generating mechanical stress when the volume is changed. When ion exchange is performed according to the present invention, _{it is possible to prevent a decrease in initial efficiency due to the formation of Li 2} O, and to effectively relieve mechanical stress generated during volume change, thereby improving lifespan characteristics.

Claims (11)

exchanging M of the compound of Formula 1 with a hydrogen ion;
drying the ion exchanged compound; and
reducing the dried compound to form a compound of Formula 2;
The reduction step is performed using a reducing agent and a scavenger, but the weight ratio of the dried compound, the reducing agent, and the scavenger is 1:0.7 to 1.3: 0.5 to 1.5. Method for producing a negative electrode material for a secondary battery:
[Formula 1]
mM ₂ O·nSiO ₂ ·yH ₂ O
[Formula 2]
SiO _x
In Formula 1, M is an alkali metal, m, n, and y are each independently 1 to 10, and in Formula 2, x is 1 to 2. According to claim 1,
M is Li, Na, or K, a method of manufacturing a negative electrode material for a secondary battery. According to claim 1,
The ion exchange step is a method of manufacturing an anode material for a secondary battery that is performed using a cation exchange resin for the compound of Formula 1 in an aqueous solution state. According to claim 1,
The drying step is a method of manufacturing an anode material for a secondary battery that is performed using a spray drying method. delete According to claim 1,
A method of manufacturing an anode material for a secondary battery, wherein the reducing agent is Mg and the scavenger is NaCl. According to claim 1,
A method of manufacturing a negative electrode material for a secondary battery further comprising the step of removing the reducing agent in an oxidized form after the reduction step. According to claim 1,
A method of manufacturing an anode material for a secondary battery, further comprising the step of forming a carbon coating layer on the compound of formula (2). 9. The method of claim 8,
The carbon coating layer is a method of manufacturing a negative electrode material for a secondary battery, which is formed by carbonizing a carbon precursor after coating the compound with Formula 2. 10. The method of claim 9,
A method of manufacturing a negative electrode material for a secondary battery, wherein the carbon precursor is a dopamine monomer or a polymer. According to claim 1,
A method of manufacturing an anode material for a secondary battery satisfying Equation 1:
[Equation 1]
(C _D1 /C _C1 )×100 > 62
In Equation 1, C _D1 is the discharge capacity in the first cycle of the secondary battery to which the negative electrode material is applied, and C _C1 is the charge capacity in the first cycle of the secondary battery to which the negative electrode material is applied.

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