KR102423962B1 - Anode Compositions and Methods for Pre-Lithitization of Anodes - Google Patents

Abstract

A novel anode composition for a lithium ion battery is provided, the anode composition comprising: a silicone-based active material; a binder selected from polyamic acids and polyimides; and a lithium salt, wherein the lithium salt may be decomposed into lithium oxide and/or lithium peroxide at a temperature of 200 to 400°C. Also provided are a method for making an anode, a method for pre-lithiating the anode, and a lithium ion battery comprising the anode.

Description

Anode Compositions and Methods for Pre-Lithitization of Anodes

The present invention relates to an anode composition for a lithium ion battery, the anode composition comprising: a silicone-based active material; a binder selected from polyimic acid and polyimide; and a lithium salt, wherein the lithium salt may be decomposed into lithium oxide and/or lithium peroxide at a temperature of 200 to 400°C. The invention also relates to a method for making an anode, a method for prelithiating the anode, and a lithium ion battery comprising the anode.

Lithium-ion batteries are currently widely used in energy storage systems and electric vehicles.

Silicon is a promising active material for the anode of lithium-ion batteries due to its large theoretical capacity and moderate operating voltage. However, during the lithiation/delithiation process, silicon undergoes rapid expansion and contraction. These massive volume changes impair the electrochemical performance of lithium-ion batteries. Moreover, silicon on the surface of the anode undesirably reacts with the electrolyte to form a solid electrolyte interface (SEI), which causes rapid capacity decay of lithium ion batteries.

It has been proposed to pre-lithiate the anode and add lithium oxide or lithium peroxide within the anode to compensate for capacity decay. The pre-lithiated anode is then assembled into a lithium ion battery. However, due to the high activity of lithium oxide and lithium peroxide, the battery manufacturing procedure after the pre-lithiation step requires a well-controlled operating environment with humidity, which increases the manufacturing cost of lithium-ion batteries. In addition, since lithium oxide and lithium peroxide powder are corrosive or irritating to human skin and mucous membranes, full protection is required in industrial production.

There is an ongoing need for more attractive and reliable lithium-ion batteries.

After intensive research, the present inventors developed a new anode composition for lithium ion batteries, the anode composition comprising:

silicone-based active materials;

a binder selected from polyamic acids and polyimides; and

Lithium salts, which can be decomposed into lithium oxide and/or lithium peroxide at a temperature of 200 to 400°C, preferably 300 to 370°C, more preferably about 340 to 360°C.

In some embodiments, the anode composition further comprises a carbon material.

Also provided is a method for making an anode, the method comprising:

mixing all components of an anode composition according to the present disclosure with a solvent to form a slurry; and

and applying the slurry onto the anode current collector.

Also provided is a method for pre-lithiating an anode prepared according to the method of the present disclosure, the method comprising: 200 to 400° C., preferably 300 to heating the anode to a temperature of 370° C., more preferably about 340 to 360° C.

Also provided is a lithium ion battery comprising an anode made according to the methods of the present disclosure or a pre-lithiated anode according to the methods of the present disclosure.

For the first time, we specifically combine polyimides and/or polyamic acids with specific lithium salts. Upon in-situ heating, the lithium salt may decompose into lithium oxide and/or lithium peroxide. The lithium oxide and/or lithium peroxide thus obtained can provide additional lithium to the anode and compensate for capacity fading, thereby greatly improving battery performance (eg initial Coulombic efficiency and cycling stability). can do.

Compared to known methods using lithium oxide or lithium peroxide directly, the present disclosure uses lithium salt as a precursor for lithium oxide and/or lithium peroxide, which is environmentally friendly and easy to perform, and does not require special operating conditions. does not

In addition, polyimide has excellent mechanical strength and is stable at the decomposition temperature of lithium salts. Thus, polyimides are superior to conventional binders used in batteries such as polyvinylidene fluoride (PVDF) and sodium carboxymethyl cellulose (CMC).

Additional features and advantages of the present disclosure will become apparent from the following detailed description taken in conjunction with the accompanying drawings, which together show by way of embodiment features of the technology, comprising:
1 compares the cycling performance of batteries according to Examples and Comparative Examples of the present disclosure.
2 compares the discharge/charge profiles of batteries according to Examples and Comparative Examples of the present disclosure.
Reference will now be made to some illustrative embodiments, and specific language will be used herein to describe them. Nevertheless, it will be understood that it is not intended to limit the scope of the present disclosure thereby.

Throughout this disclosure, all scientific and technical terms have the same meaning as known to one of ordinary skill in the art, unless otherwise indicated. In case of inconsistency, the definition provided in this disclosure should be taken.

It is to be understood that the detailed description of all materials, processes, examples, and drawings is presented for purposes of illustration and is not to be construed as a limitation of the present disclosure, unless specifically stated otherwise.

As used herein, the terms “cell” and “battery” may be used interchangeably. Also, the term “lithium ion cell (or battery)” may be abbreviated as “cell” or “battery”.

As used herein, the term “comprising” means that other ingredients or other steps that do not affect the final effect may be included. This term includes the terms "consisting of" and "consisting essentially of." Articles and methods according to the present disclosure are not limited to the essential technical features and/or limitations of the present disclosure described herein, as well as any additional and/or optional ingredients, components, steps, or limitations described herein. may include, may consist of, and may consist essentially of.

The use of the terms "a", "an" and "the" and similar designators in the context of describing the subject matter of the present application (especially in the context of the following claims) is not otherwise indicated herein or otherwise clearly contradicted by context. unless otherwise construed to cover both the singular and the plural.

Unless otherwise specified, all numerical ranges in this context are intended to include all numbers and subranges and endpoints falling within that numerical range.

Unless otherwise indicated, all materials and formulations used in this disclosure are commercially available.

Embodiments of the present disclosure are described in detail as follows.

anode

The components of the “anode composition” may be mixed with a solvent to form an anode slurry. The anode slurry may then be applied onto the anode current collector and dried to form the anode.

In some embodiments, an anode composition for a lithium ion battery is provided, the anode composition comprising:

silicone-based active materials;

a binder selected from polyamic acids and polyimides; and

Lithium salts, which can be decomposed into lithium oxide and/or lithium peroxide at a temperature of 200 to 400°C, preferably 300 to 370°C, more preferably about 340 to 360°C.

In some embodiments, the anode composition may further include a carbon material.

In some embodiments, the anode composition comprises, based on the total weight of the anode composition,

5 to 60% by weight, preferably 5 to 40% by weight of a silicone-based active material;

3 to 15% by weight, preferably 3 to 10% by weight of a binder selected from polyamic acids and polyimides;

2 to 30% by weight, preferably 2 to 20% by weight of a lithium salt, the lithium salt capable of decomposing into lithium oxide and/or lithium peroxide at a temperature of 200 to 400° C.; and

0 to 90% by weight, preferably 30 to 85% by weight, more preferably 40 to 85% by weight of carbon material.

Each component of the anode composition of the present disclosure will be described in detail below.

Silicone-based active material

An anode composition according to the present disclosure may include a silicone-based active material. Compared with the carbon-based active material, the silicon-based active material has a larger theoretical capacity and a more moderate operating voltage.

As used herein, the term “active material” refers to a material capable of allowing lithium ions to intercalate therein and release lithium ions therefrom during repeated charge/discharge cycles.

A “silicone-based active material” may be an active material containing a silicone component. There are no particular restrictions on the silicon-based active material, and those known for use in lithium ion batteries can be used. Examples of suitable silicon-based active materials may include, but are not limited to, silicon, silicon alloys, silicon oxide, silicon/carbon composites, silicon oxide/carbon composites, and any combination thereof. In some embodiments, the silicon alloy may include silicon and one or more metals selected from the group consisting of Ti, Sn, Al, Sb, Bi, As, Ge, and Pb. Commercially available silicon alloys may include, but are not limited to, Si-Fe-Ti alloy powders available from 3M. In some embodiments, the silicon oxide may be a mixture of more than one silicon oxide. For example, silicon oxide may be expressed as SiO _x , where the average value of x may be about 0.5 to about 2.

In some embodiments, the content of the silicone-based active material is 5 to 60% by weight, preferably 5 to 40% by weight, based on the total weight of the anode composition. The total weight of the anode composition means the dry weight not including the weight of the solvent.

binder

The anode composition according to the present disclosure may include a binder selected from polyamic acid and polyimide. The binder can hold the components of the anode composition together, attach the anode composition to the anode current collector, and help maintain good stability and integrity of the anode when volume changes occur during repeated charge/discharge cycles, The electrochemical properties of the final cell (including cycling performance and rate performance) can be improved.

In addition, compared with conventional binders that cannot withstand the high decomposition temperature of lithium salts (eg PVDF and CMC), polyamic acid and polyimide have high heat resistance and are stable at the decomposition temperature of lithium salts. In some embodiments, the resulting polyimide is stable at high temperatures, although the polyamic acid may dehydrate upon heating. In addition, polyamic acid and polyimide have excellent mechanical strength, thereby helping to prevent volume change during repeated charge/discharge cycles, which is advantageous for the electrochemical properties of the final cell.

There are no special restrictions on polyimide and polyamic acid, and those commonly known may be used.

Polyimides may include aromatic polyimides, aliphatic polyimides, and alicyclic polyimides. The repeating units of the polyimide may comprise -C(O)-N-C(O)- and one or more aromatic, aliphatic and/or aliphatic ring components.

In some embodiments, the polyimide may be represented by Formula I:

[Formula I]

wherein R ¹ and R ² may each independently be a C1-C12 alkyl group, a C1-C12 alkylene group, or a C1-C12 alkynyl group; preferably a C1-C6 alkyl group; m may be an integer from 2 to 50, preferably from 2 to 30.

In some embodiments, the polyimide may be represented by Formula II:

[Formula II]

wherein Ar represents a C6-C30 aromatic group; R ³ may be a C1-C12 alkyl group, a C1-C12 alkenyl group, or a C1-C12 alkynyl group; preferably a C1-C6 alkyl group; n may be an integer from 2 to 50, preferably from 2 to 30.

In some embodiments, the polyimide may be represented by Formula III:

[Formula Ⅲ]

wherein R ³ and n each have the same definitions as described above for formula II; R ⁴ may independently be a C1-C12 alkyl group, a C1-C12 alkenyl group, or a C1-C12 alkynyl group; Preferably, it may be a C1-C6 alkyl group.

The polyamic acid may include an aromatic polyamic acid, an aliphatic polyamic acid, and an aliphatic cyclic polyamic acid. The repeating unit of the polyamic acid may comprise a carboxyl group -C(O)OH, a polyamide group -C(O)-NH-, and one or more aromatic, aliphatic and/or aliphatic ring components.

In some embodiments, the polyamic acid may be represented by Formula IV:

[Formula IV]

wherein Ar, R ³ and n each have the same definitions as described above for formula II.

In some embodiments, the polyamic acid may be represented by Formula V:

[Formula V]

wherein R ³ , R ⁴ and n each have the same definitions as described above for formula III.

To facilitate the application of the anode slurry onto the anode collector, the polyamic acid and polyimide are preferably soluble in the solvent used to form the anode slurry (eg, N-methyl-2-pyrrolidone). to be.

In some embodiments, the amount of binder is 3 to 15% by weight, preferably 3 to 10% by weight, based on the total weight of the anode composition.

lithium salt

The anode composition according to the present disclosure comprises a lithium salt capable of decomposing into lithium oxide and/or lithium peroxide at a temperature of 200 to 400 °C, preferably 300 to 370 °C, more preferably about 340 °C to 360 °C can do.

Upon in situ heating, the lithium salt may decompose into lithium oxide and/or lithium peroxide. The lithium oxide and/or lithium peroxide thus obtained can provide an additional lithium source and compensate for capacity fading, thereby greatly improving battery performance (eg, initial coulombic efficiency and cycling stability).

Compared with the known method using lithium oxide or lithium peroxide directly, the present disclosure uses a lithium salt as a precursor of lithium oxide, which is environmentally friendly and easy to perform, and does not require special operating conditions.

In some embodiments, the lithium salt is selected from the group consisting of lithium acetate, lithium oxalate, lithium citrate, and lithium bicarbonate.

The weight ratio of lithium salt to silicone-based active material depends on the particular type of lithium salt and silicone-based active material used. Preferably, the weight ratio of lithium in the lithium salt to silicon in the silicone-based active material is from 5:100 to 25:100, preferably from 7:100 to 20:100. As the lithium to silicon ratio is controlled within these ranges, the battery can be pre-lithiated to a desirable high level, while avoiding introducing too much lithium to reduce the mass density of the battery.

In some embodiments, the content of lithium salt is from 2 to 30% by weight, preferably from 2 to 20% by weight, based on the total weight of the anode composition.

menstruum

As noted above, an anode composition according to the present disclosure may be mixed with a solvent to form an anode slurry. When heating the anode during the subsequent pre-lithiation step, the solvent evaporates. Thus, the pre-lithiated anode contains only a small amount of solvent or no solvent.

There are no particular restrictions on the solvent, and those known for use in lithium ion batteries can be used. An example of a suitable solvent includes N-methyl-2-pyrrolidone (NMP).

carbon material

The anode composition may further comprise a carbon material. A “carbon material” may be a material containing a carbon component. The carbon material may act as an active material that is different from the silicone-based active material, or may increase the electrical conductivity and/or dispersibility of the anode composition. There are no special restrictions on the carbon material, and those known for use in lithium ion batteries can be used. In some embodiments, the carbon material may include, but is not limited to, carbon black, acetylene black, Ketjen black, graphite, graphene, carbon nanotubes, carbon fibers, vapor grown carbon fibers, and combinations thereof. doesn't happen In some embodiments, the carbon black may be Super P (eg, Super P commercially available from Timcal, particle size: about 20 nm or about 40 nm). In some embodiments, the graphite may be graphite powder (e.g., particle size: 2-30 μm), and/or graphite flakes (e.g., KS6L commercially available from Timcal, particle size: about 6 μm). have. The carbon materials may be used individually or in any combination.

In some embodiments, graphite powder, Super P and graphite flakes may be used in combination of two or three of them. The graphite powder can act as the carbon-based active material at the anode to buffer the volume change caused by the silicon-based active material. Super P has a relatively smaller particle size and good electrical conductivity, and can improve the electrical conductivity and dispersibility of the anode. Graphite flakes have a relatively larger particle size and good electrical conductivity, and can improve two-dimensional electrical conductivity, two-dimensional dispersibility and cycling performance.

The anode may optionally contain, in addition to the above-mentioned components, additives conventionally used in the electrode, so long as they do not adversely impair battery performance.

There are no special restrictions on the type, shape, size and/or content of each component of the anode composition.

In some embodiments, the content of carbon material is 0 to 90% by weight, preferably 30 to 85% by weight, more preferably 40 to 85% by weight, based on the total weight of the anode composition.

anode method for manufacturing

In some embodiments, a method is provided for making an anode, the method comprising:

mixing all components of an anode composition according to the present disclosure with a solvent to form a slurry; and

and applying the slurry onto the anode current collector.

In some embodiments, the solvent may include N-methyl-2-pyrrolidone (NMP).

There are no special restrictions on the anode current collector. In some embodiments, a nickel foil, nickel net, copper foil or copper net may be used as the anode current collector.

In some embodiments, the method further comprises a calendering step. During the decomposition of lithium salts, gases are generated and voids are formed. By calendering, the pores of the anode can be well controlled, lithium oxide and/or lithium peroxide can be uniformly distributed in the anode, and battery performance can be improved.

anode dictionary to lithiate way for

In some embodiments, a method is provided for pre-lithiating an anode prepared according to the method of the present disclosure, the method comprising: 200 to 400° C., preferably to decompose a lithium salt into lithium oxide and/or lithium peroxide comprises heating the anode to a temperature of 300 to 370 °C, more preferably about 340 to 360 °C. As the temperature falls within these ranges, the polyimide and/or polyamic acid exhibits excellent crosslinking strength, and the electrode current collector is not destroyed.

lithium ion battery

In some embodiments, a lithium ion battery comprising an anode made according to the methods of the present disclosure or pre-lithiated is provided. In addition, the lithium ion battery further includes a cathode and an electrolyte.

Lithium ion batteries according to the present disclosure can be used in energy storage systems and electric vehicles.

cathode

The “cathode composition” may be mixed to form a cathode slurry. A cathode slurry may then be applied onto the cathode current collector and dried to form a cathode.

According to some embodiments of the present disclosure, the cathode may include a lithium-based active material. In some embodiments, the cathode active material may be a material that reversibly desorbs and intercalates lithium ions during a charge/discharge cycle. In the discharge cycle, lithium ions originating from the lithium-based active material may be transferred from the anode back to the cathode to re-form the lithium-based active material.

There is no particular limitation on the lithium-based cathode active material, and such cathode active material commonly used in lithium ion batteries may be used. In some embodiments, the cathode active material may be selected from the group consisting of lithium metal oxide, lithium metal phosphate, lithium metal silicate and any combination thereof, preferably lithium transition metal composite oxide, lithium transition metal phosphate, lithium metal silicates and any combination thereof. In some embodiments, the cathode active material may be selected from the group consisting of lithium iron phosphate, lithium manganese phosphate, lithium manganese iron phosphate, and any combination thereof. In some embodiments, the lithium transition metal composite oxide is lithium nickel oxide, lithium cobalt oxide, lithium manganese oxide, lithium nickel cobalt oxide, lithium nickel manganese oxide, lithium nickel cobalt manganese oxide (NCM), lithium nickel cobalt aluminum oxide (NCA) , a lithium nickel cobalt manganese oxide/Li ₂ MnO ₃ composite (also referred to as a “lithium-rich NCM”), or any combination thereof. The transition metal may include any transition metal from Groups 3 to 12 of the Periodic Table, such as titanium, zinc, copper, nickel, and molybdenum.

In some embodiments, the cathode composition may further include a carbon material, a binder, and a solvent in addition to the lithium-based cathode active material.

There are no special restrictions on the binder, and those known for use in lithium ion batteries can be used. In some embodiments, the binder may be polyvinylidene fluoride (PVDF), polyacrylic acid (PAA) and derivatives thereof (eg, LiPAA), sodium carboxymethyl cellulose (CMC), and combinations thereof.

The above description of the carbon material and solvent of the anode is applicable here as well. The carbon material and solvent of the cathode may be the same or different from those contained in the anode, respectively.

In addition, other additives commonly known for use in lithium ion batteries may optionally be used in the cathode as long as they do not adversely impair the desired battery performance.

There are no particular restrictions on the type, shape, size and/or content of each component of the cathode composition.

There are no special restrictions on the cathode current collector. In some embodiments, aluminum foil may be used as the cathode current collector.

electrolyte

A lithium ion battery according to the present disclosure may include an electrolyte. According to some embodiments of the present disclosure, the electrolyte may include a lithium salt and a non-aqueous solvent. There are no special restrictions on lithium salts and non-aqueous solvents, and those lithium salts and non-aqueous solvents commonly known for batteries can be used. In some embodiments, the lithium salt of the electrolyte may be different from the lithium salt of the anode and the lithium-based active material of the cathode. According to some embodiments of the present disclosure, the lithium salt is lithium hexafluorophosphate (LiPF ₆ ), lithium tetrafluoroborate (LiBF ₄ ), lithium arsenate (LiAsO ₄ ), LiSbO ₄ , lithium perchlorate (LiC 1 O ₄ ), LiAlO ₄ , LiGaO ₄ , lithium bis(oxalate)borate (LiBOB), and any combination thereof, with LiPF ₆ being preferred.

In accordance with some embodiments of the present disclosure, the non-aqueous solvent of the electrolyte may include a carbonate (ie, a non-fluorinated carbonate) and a fluorinated carbonate. According to some embodiments of the present disclosure, the carbonate is selected from the group consisting of cyclic carbonates such as ethylene carbonate (EC), propylene carbonate (PC), butylene carbonate (BC); linear or branched carbonates such as dimethyl carbonate (DMC), diethyl carbonate (DEC), dipropyl carbonate (DPC), ethyl methyl carbonate (EMC), methylpropyl carbonate (MPC), ethylpropyl carbonate (EPC); and any combination of the aforementioned carbonates. In accordance with some embodiments of the present disclosure, the fluorinated carbonate may be a fluorinated derivative of the aforementioned carbonate, such as fluoroethylene carbonate (FEC) and difluoroethylene carbonate, difluorinated dimethyl carbonate (DFDMC).

Example

ingredient

NCM-111: lithium nickel cobalt manganese oxide, active material for cathode, D50: 12 μm, available from BASF.

Super P: carbon material for cathode and anode, 40 nm, available from Timcal.

PVDF: polyvinylidene fluoride, cathode binder, available from Sovey.

Si-Fe-Ti alloy powder: active material of anode, silicon content: 30% by weight, diameter: 50 nm, available from 3M.

Graphite powder: active material of anode, diameter: 20 μm, available from Hitachi.

KS6L: Graphite piece, carbon material of anode, about 6 μm, available from Timcal.

U-Varnish A: Anode binder, a mixture of 20% by weight polyamic acid and 80% by weight N-methyl-2-pyrrolidinone, available from UBE.

Lithium Acetate: Lithium salt, source of pre-lithiation of the anode, available from Guoyao.

NMP: N-methyl-2-pyrrolidone, solvent, available from Guoyao.

Celgard2325: PP/PE/PP membrane, separator, available from Celgard.

Example 1 (Ex. 1): Preparation of a battery

cathodic Produce

At room temperature, 96.5 g of NCM-111, 3 g of Super P and 2.5 g of PVDF were added into 47 g of NMP in a 500 mL round bottom flask equipped with a stirrer. After stirring for 3 hours, the resulting uniformly dispersed slurry was coated on aluminum foil and then dried at 80° C. for 6 hours. The coated Al foil was cut with several Φ12 mm cathodes.

anode Produce

At room temperature, 40 g of Si-Fe-Ti alloy powder, 40 g of graphite powder, 10 g of lithium acetate, 10 g of U-varnish A (dry weight, in the form of a solution of 20% by weight in NMP), 2 g of Super P and 8 g of KS6L were added into 70 g of NMP in a 500 mL round bottom flask equipped with a stirrer. After stirring for 3 hours, the resulting uniformly dispersed slurry was coated on copper foil and then dried at 60° C. for 30 minutes. The coated Cu foils were then calcined in a tubular furnace purged with nitrogen gas (RS 80/750/11, Nabertherm) at a heating rate of 20° C./min until the temperature reached 350° C. The coated Cu foil was then removed from the tubular oven and cooled to room temperature (about 25° C.). The coated Cu foil was cut into several Φ12 mm anodes.

manufacture of batteries

A coin cell (CR2016) was assembled in an argon-filled glove box (MB-10 compact, MBraun) by using the cathode and anode obtained as above. 1M LiPF ₆ was used as electrolyte in FEC/EC/EMC (30:35:35 by volume). Celgard 2325 was used as separator.

comparative example 1 (Com. Ex. 1)

A coin cell was prepared in the same manner as described above for Example 1, except that lithium acetate was not used.

[electrochemical measurements]

The battery performance of each cell obtained in Example 1 and Comparative Example 1 was measured with an Arbin battery test system (model: Arbin BT-G; supplier: Arbin) at 25°C.

Each cell was charged to 4.2 V (versus Li/Li ⁺ ) at a current of 0.1 C during the first charge cycle. The cell was then discharged to 2.5 V at a current of 0.1 C during the first discharge cycle. The aforementioned charge/discharge cycle was repeated in the second and third cycles. Each cell was then charged to 4.2 V (versus Li/Li ⁺ ) at various rates during the fourth to twenty-first charge cycles. Specifically, the charging rate is 0.1 C for the 4th to 6th charging cycles, 1/3 C for the 7th to 9th charging cycles, 0.5 C for the 10th to 12th charging cycles, 1 C for the 13th to 15th charging cycles , 2 C for the 16th to 18th charge cycles, and 3 C for the 19th to 21st charge cycles. The battery was discharged to 2.5 V at a current of 0.1 C during the fourth to twenty-first discharge cycles. Finally, each cell was discharged/charged within a voltage range of 2.5 to 4.5 V (versus Li/Li ⁺ ) and at a rate of 1 C during subsequent cycles. The mass loading of the NCM at each cathode of the cell was about 10 mg/cm ² . The specific capacity was calculated based on the weight of the NCM.

1 compares the cycling performance of the batteries in Example 1 and Comparative Example 1. Referring to FIG. 1 , it can be seen that Example 1 exhibited better cycling stability as compared to Comparative Example 1 in which no prior lithiation source was used.

2 compares the discharge/charge profiles of the batteries in Example 1 and Comparative Example 1. Referring to FIG. 2 , it can be seen that Example 1 exhibited a higher initial Coulombic efficiency in the first charge/discharge cycle, as compared to Comparative Example 1 in which no prior lithiation source was used.

Claims (10)

An anode composition for a lithium ion battery comprising:
Based on the total weight of the anode composition,
5 to 60% by weight of a silicon-based active material;
3 to 15% by weight of a binder selected from polyamic acids and polyimides;
2 to 30% by weight of a lithium salt, the lithium salt capable of decomposing into lithium oxide and/or lithium peroxide at a temperature of 200 to 400° C.; and
0 to 90% by weight of carbon material;
An anode composition for a lithium ion battery. According to claim 1,
wherein the binder is soluble in N-methyl-2-pyrrolidone. According to claim 1,
The lithium salt is selected from the group consisting of lithium acetate, lithium oxalate, lithium citrate and lithium bicarbonate. According to claim 1,
wherein the silicon-based active material is selected from the group consisting of silicon, silicon alloys, silicon oxides, silicon/carbon composites and silicon oxide/carbon composites. According to claim 1,
wherein the carbon material is selected from the group consisting of carbon black, acetylene black, Ketjen black, graphite, graphene, carbon nanotubes, carbon fibers and vapor grown carbon fibers. 6. The method according to any one of claims 1 to 5,
Based on the total weight of the anode composition,
5 to 40% by weight of a silicone-based active material;
3 to 10% by weight of a binder selected from polyamic acids and polyimides;
2 to 20% by weight of a lithium salt, the lithium salt capable of decomposing into lithium oxide and/or lithium peroxide at a temperature of 200 to 400° C.; and
30 to 85% by weight of carbon material. A method for manufacturing an anode comprising:
mixing all components of the anode composition according to claim 1 with a solvent to form a slurry; and
applying the slurry onto an anode current collector;
A method for manufacturing an anode. A method for pre-lithiation of an anode prepared according to the method of claim 7, comprising:
heating the anode to a temperature of 200 to 400° C. to decompose the lithium salt into lithium oxide and/or lithium peroxide;
A method for pre-lithiating an anode prepared according to the method of claim 7. A lithium ion battery comprising:
9, comprising an anode prepared according to the method of claim 7 or a pre-lithiated anode according to the method of claim 8,
lithium ion battery. 7. The method of claim 6,
Based on the total weight of the anode composition,
40 to 85% by weight of carbon material.

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