lithium-ion batteries

Abstract

A lithium-ion battery comprises a positive electrode having a positive electrode mixture layer containing a positive electrode active material and a negative electrode having a negative electrode mixture layer containing a negative electrode active material. The lithium-ion battery charges and discharges by transferring lithium ions between the positive and negative electrodes. The negative electrode mixture layer comprises a negative electrode active material represented by the general formula M3Me2X7 (wherein M comprises at least one member selected from the group consisting of La, Ce, Ba, Sr, Zr, Ca, Mg, and Y; Me comprises at least one member selected from the group consisting of Ti, V, Cr, Nb, Mn, Ni, Fe, Co, and Cu; and X comprises at least one member selected from the group consisting of Ge, Si, Sn, Al, P, Sb, and B); and a binder comprising ammonium carboxymethylcellulose (NH4-CMC).

Description

Technical Field

[0001] The present disclosure relates to a lithium ion battery comprising a positive electrode having a positive electrode mixture layer containing a positive electrode active material and a negative electrode having a negative electrode mixture layer containing a negative electrode active material. The lithium ion battery is charged and discharged by lithium ions moving between the positive electrode and the negative electrode. Background Art

[0002] Lithium-ion batteries, which charge and discharge by the movement of lithium ions (Li ions) between the negative electrode and the positive electrode, are widely used. Graphite-based negative electrode active materials are often used in the negative electrode mixture layer of these lithium-ion batteries. Graphite-based negative electrode active materials are sometimes used in conjunction with silicon. However, this leads to significant volume changes during charge and discharge, which can deteriorate capacity retention and increase costs.

[0003] Therefore, negative electrode active materials other than graphite have been proposed. For example, Patent Document 1 describes a proposal to use an alloy having a La 3 Co 2 Sn 7 type crystal structure as a negative electrode active material.

[0004] Furthermore, a binder is used in the negative electrode mixture layer to prevent delamination and cracking. However, if the amount of binder increases, the efficiency of the battery reaction of the negative electrode active material decreases. Therefore, there is a demand to reduce the amount of binder. Patent Document 2 describes a method of reducing the binder content to 0.5% by mass or more and 5.0% by mass or less.

[0005] Prior art literature

[0006] Patent Literature

[0007] Patent Document 1: Japanese Patent No. 4127692

[0008] Patent Document 2: Japanese Patent Application Laid-Open No. 2007-258127 Summary of the Invention

[0009] Patent Document 1 uses polyvinylidene fluoride (PVdF) as a binder, but experimental results show that when an alloy with a La3Co2Sn7 type crystal structure is used as the negative electrode active material and PVdF is used as the binder, the mixture slurry used in the formation of the negative electrode mixture layer will gel due to the reaction between the two, making coating difficult. In order to reduce the reactivity of La3Ni2Sn7 and PVdF and enable coating, the particle size of the negative electrode active material must be increased. However, if the particle size of the negative electrode active material is increased, the reactivity of the negative electrode active material with Li decreases, and the capacity is easily reduced.

[0010] In addition, alloys having a La3Co2Sn7 type crystal structure may undergo alloying reactions due to the binder and may sometimes form impurity alloys. In this case, the cycle characteristics may be reduced.

[0011] The lithium-ion battery disclosed herein comprises: a positive electrode having a positive electrode mixture layer containing a positive electrode active material; and a negative electrode having a negative electrode mixture layer containing a negative electrode active material. The lithium-ion battery is charged and discharged by the movement of lithium ions between the positive electrode and the negative electrode. The negative electrode mixture layer contains: a negative electrode active material represented by the general formula M3Me2X7 (wherein M comprises at least one member selected from the group consisting of La, Ce, Ba, Sr, Zr, Ca, Mg, and Y, Me comprises at least one member selected from the group consisting of Ti, V, Cr, Nb, Mn, Ni, Fe, Co, and Cu, and X comprises at least one member selected from the group consisting of Ge, Si, Sn, Al, P, Sb, and B); and a binder comprising ammonium carboxymethylcellulose (NH4-CMC).

[0012] In addition, the lithium ion battery disclosed herein includes: a positive electrode having a positive electrode mixture layer containing a positive electrode active material, and a negative electrode having a negative electrode mixture layer containing a negative electrode active material, wherein the lithium ion battery is charged and discharged by the movement of lithium ions between the aforementioned positive electrode and the aforementioned negative electrode, and the aforementioned negative electrode mixture layer contains: a negative electrode active material represented by the general formula M3Me2X7 (wherein, M includes at least one selected from the group consisting of La, Sr, Ca, Mg and Y, Me includes at least one selected from the group consisting of Mn, Ni, Fe, Co and Cu, and X includes at least one selected from the group consisting of Ge, Si, Sn, Al and B); and a binder including carboxymethylcellulose ammonium (NH4-CMC).

[0013] In the present disclosure, a substance represented by the general formula M3Me2X7 (wherein M comprises at least one member selected from the group consisting of La, Ce, Ba, Sr, Zr, Ca, Mg, and Y, Me comprises at least one member selected from the group consisting of Ti, V, Cr, Nb, Mn, Ni, Fe, Co, and Cu, and X comprises at least one member selected from the group consisting of Ge, Si, Sn, Al, P, Sb, and B) such as La3Ni2Sn7 is used as the negative electrode active material. This enables coating of the negative electrode mixture layer while suppressing a decrease in capacity and a decrease in cycle characteristics. Furthermore, by using an aqueous binder, coating can be performed inexpensively. BRIEF DESCRIPTION OF THE DRAWINGS

[0014] Figure 1 It is a longitudinal cross-sectional view of a cylindrical secondary battery 10 as an example of an embodiment.

[0015] Figure 2It is a figure which shows the X-ray diffraction spectrum of the electrode of an Example and a comparative example.

[0016] Figure 3A This is a graph showing the charge and discharge characteristics in Examples, and is a graph showing the relationship between capacity and electrode potential.

[0017] Figure 3B This is a graph showing the charge and discharge characteristics in Examples, and is a graph showing the relationship between the number of cycles and the capacity.

[0018] Figure 4 This is a graph showing the charge and discharge characteristics of Comparative Example 1 using SBR / Na-CMC as a negative electrode binder. DETAILED DESCRIPTION

[0019] Hereinafter, embodiments of the present disclosure will be described based on the drawings. However, it should be noted that the present disclosure is not limited to the embodiments described here.

[0020] [About negative electrode materials]

[0021] Lithium-ion battery anode materials preferably meet the requirements of high energy density and low expansion. Consequently, various research and development efforts have led to the use of intermetallic compounds represented by M3Me2X7 (M = La, Ca, Me = Mn, Ni, Fe, Co, X = Ge, Si, Sn, Al), such as La3Ni2Sn7, as anode active materials. These intermetallic compounds store and release lithium through intercalation reactions, resulting in low expansion coefficients and the potential for extended battery life.

[0022] However, it is clear that this material requires further improvement for practical use. First, as mentioned above, using PVdF as a binder can cause the negative electrode mixture slurry to gel, making the application of the negative electrode mixture layer difficult. Furthermore, increasing the binder particle size to suppress gelation can potentially hinder battery reaction.

[0023] In addition, by using a cyano group-containing binder such as polyacrylonitrile (PAN), gelation of the negative electrode mixture slurry can be suppressed. However, PAN is an organic binder and requires coating using an organic solvent, making it difficult to apply inexpensively.

[0024] Furthermore, if polyimide (PI) or styrene butadiene rubber / sodium carboxymethyl cellulose (SBR / Na-CMC) is used, an alloying reaction occurs with the La3Ni2Sn7 type crystal alloy serving as the negative electrode active material, and the cycle characteristics may be degraded.

[0025] [Configuration of Embodiment]

[0026] Figure 1It is a longitudinal cross-sectional view of a cylindrical secondary battery 10 as an example of an embodiment. Figure 1 In the secondary battery 10 shown, the electrode body 14 and the non-aqueous electrolyte are housed in an outer shell 15. The electrode body 14 has a wound structure in which the positive electrode 11 and the negative electrode 12 are wound with a separator 13 interposed therebetween. As a non-aqueous solvent (organic solvent) for the non-aqueous electrolyte, carbonates, lactones, ethers, ketones, esters, etc. can be used, and these solvents can be mixed and used in combination of two or more. When two or more solvents are mixed and used, a mixed solvent containing cyclic carbonates and chain carbonates is preferably used. For example, as cyclic carbonates, ethylene carbonate (EC), propylene carbonate (PC), butylene carbonate (BC), etc. can be used, and as chain carbonates, dimethyl carbonate (DMC), ethyl methyl carbonate (EMC), and diethyl carbonate (DEC), etc. can be used. As electrolyte salts for the non-aqueous electrolyte, LiPF6, LiBF4, LiCF3SO3, etc., and mixtures thereof can be used. The amount of the electrolyte salt dissolved in the non-aqueous solvent can be, for example, 0.5 to 2.0 mol / L. In addition, for the sake of convenience, the following description will be made with the sealing body 16 side referred to as “upper” and the bottom side of the outer shell 15 referred to as “lower”.

[0027] The open end of the outer shell 15 is blocked by the sealing body 16, thereby sealing the interior of the secondary battery 10. Insulating plates 17 and 18 are provided above and below the electrode body 14, respectively. The positive lead 19 extends upward through the through hole of the insulating plate 17 and is welded to the lower surface of the partially opened metal plate 22 serving as the bottom plate of the sealing body 16. In the secondary battery 10, the top plate of the sealing body 16, i.e., the cover 26, which is electrically connected to the partially opened metal plate 22, serves as the positive terminal. On the other hand, the negative lead 20 extends toward the bottom side of the outer shell 15 through the through hole of the insulating plate 18 and is welded to the bottom inner surface of the outer shell 15. In the secondary battery 10, the outer shell 15 serves as the negative terminal. It should be noted that when the negative lead 20 is provided at the terminal portion, the negative lead 20 extends toward the bottom side of the outer shell 15 through the outside of the insulating plate 18 and is welded to the bottom inner surface of the outer shell 15.

[0028] The outer shell 15 is, for example, a cylindrical metal outer can with a bottom. A gasket 27 is provided between the outer shell 15 and the sealing member 16 to ensure the airtightness of the interior of the secondary battery 10. The outer shell 15 has, for example, a groove 21 formed by applying pressure to the side surface from the outside to support the sealing member 16. The groove 21 is preferably formed in an annular shape along the circumference of the outer shell 15, and its upper surface supports the sealing member 16 via the gasket 27.

[0029] The sealing body 16 includes: a partially open metal plate 22, a lower valve body 23, an insulating member 24, an upper valve body 25, and a cover 26, which are stacked in sequence from the electrode body 14 side. The components constituting the sealing body 16 have, for example, a disc shape or a ring shape, and the components except the insulating member 24 are electrically connected to each other. The lower valve body 23 and the upper valve body 25 are connected to each other at their respective central portions, and the insulating member 24 is sandwiched between their respective peripheral portions. When the internal pressure of the battery rises due to abnormal heat release, for example, the lower valve body 23 will break, whereby the upper valve body 25 expands toward the cover 26 side and detaches from the lower valve body 23, thereby cutting off the electrical connection between the two. When the internal pressure rises further, the upper valve body 25 breaks, and the gas is discharged from the opening 26a of the cover 26.

[0030] Hereinafter, the positive electrode 11 , the negative electrode 12 , and the separator 13 constituting the electrode assembly 14 , and in particular, the negative electrode active material constituting the negative electrode 12 will be described.

[0031] [positive electrode]

[0032] The positive electrode 11 has: a positive electrode core, and a positive electrode mixture layer provided on the surface of the positive electrode core. The positive electrode core can be made of a foil of a metal such as aluminum that is stable within the potential range of the positive electrode 11, or a thin film having the metal provided on the surface. The thickness of the positive electrode core is, for example, 10 μm to 30 μm. The positive electrode mixture layer contains a positive electrode active material, a binder, and a conductive material, and is preferably provided on both sides of the positive electrode core except for the portion connected to the positive electrode lead 19. The positive electrode 11 can be produced, for example, as follows: a positive electrode mixture slurry containing a positive electrode active material, a binder, and a conductive material is applied to the surface of the positive electrode core, the coating is dried, and then compressed to form positive electrode mixture layers on both sides of the positive electrode core.

[0033] The positive electrode active material contains a lithium transition metal oxide as a main component. The positive electrode active material may consist essentially solely of the lithium transition metal oxide. Inorganic compound particles such as aluminum oxide and lanthanide-containing compounds may also be attached to the surface of the lithium transition metal oxide particles. The lithium transition metal oxide may be used alone or in combination of two or more.

[0034] Examples of metal elements contained in the lithium transition metal oxide include nickel (Ni), cobalt (Co), manganese (Mn), aluminum (Al), boron (B), magnesium (Mg), titanium (Ti), vanadium (V), chromium (Cr), iron (Fe), copper (Cu), zinc (Zn), gallium (Ga), strontium (Sr), zirconium (Zr), niobium (Nb), indium (In), tin (Sn), tantalum (Ta), and tungsten (W). An example of a suitable lithium transition metal oxide is a general formula: Li α Ni x M (1-x)A composite oxide represented by O2 (0.1≤α≤1.2, 0.3≤x<1, M contains at least one of Co, Mn, and Al). For example, NCA, in which a portion of nickel is substituted with cobalt and aluminum is added, is used as a positive electrode material.

[0035] Examples of conductive materials included in the positive electrode mixture layer include carbon materials such as carbon black, acetylene black, Ketjen black, carbon nanotubes, carbon nanofibers, and graphite. Examples of binders included in the positive electrode mixture layer include fluororesins such as polytetrafluoroethylene (PTFE) and polyvinylidene fluoride (PVdF), polyacrylonitrile (PAN), polyimide resins, acrylic resins, and polyolefin resins. These resins can be used in combination with cellulose derivatives such as carboxymethyl cellulose (CMC) or its salts, polyethylene oxide (PEO), and the like.

[0036] [negative electrode]

[0037] The negative electrode 12 includes a negative electrode core and a negative electrode mixture layer provided on the surface of the negative electrode core. The negative electrode core can be made of a foil of a metal such as copper that is stable within the potential range of the negative electrode 12, or a thin film having the metal disposed on the surface. The thickness of the negative electrode core is, for example, 5 μm to 15 μm. The negative electrode mixture layer contains a negative electrode active material and a binder, and is preferably provided on both sides of the negative electrode core, excluding the portion connected to the negative electrode lead 20. The negative electrode 12 can be produced, for example, by applying a negative electrode mixture slurry containing a negative electrode active material and a binder to the surface of the negative electrode core, drying the coating, and then compressing the coating to form negative electrode mixture layers on both sides of the negative electrode core. In addition, a conductive material can also be added to the negative electrode mixture slurry. The conductive material can make the conductive path uniform. In addition, the negative electrode mixture layer, like the positive electrode mixture layer, can also contain a conductive material such as acetylene black.

[0038] The negative electrode mixture layer contains, as a negative electrode active material, an intermetallic compound (an alloy of M3Me2X7 type crystals) represented by the general formula M3Me2X7 (wherein M comprises at least one of La and Ca, Me comprises at least one of Mn, Ni, Fe, and Co, and X comprises at least one of Ge, Si, Sn, and Al). Specific examples of suitable negative electrode active materials include La3Co2Sn7, La3Mn2Sn7, and La3Ni2Sn7. Among them, La3Co2Sn7 or La3Ni2Sn7 are preferred, and La3Ni2Sn7 is particularly preferred from the perspective of increasing capacity.

[0039] The particle size of M3Me2X7 as the negative electrode active material is preferably 1 to 30 μm, more preferably 2 to 20 μm, and particularly preferably 2 to 10 μm. If the particle size of M3Me2X7 becomes excessively large, the reactivity with Li will decrease, and the contact area between the particles will decrease, and the resistance will increase. On the other hand, if the particle size becomes excessively small, the filling density of the negative electrode active material will decrease, and the assumed capacity will decrease. The average particle size of M3Me2X7 is, for example, 3 to 15 μm, or 5 to 10 μm. The particle size of M3Me2X7 is measured as follows: it is measured in the form of the diameter of the circumscribed circle of the M3Me2X7 particles in the cross-sectional image of the negative electrode mixture layer observed using a scanning electron microscope (SEM). The average particle size is calculated by averaging the particle sizes of any 100 particles.

[0040] The intermetallic compound represented by M3Me2X7 can be formed by arc melting, and annealing after arc melting is suitable. In addition, regarding M, La can be replaced by about 50%. For example, when about 40% of La is replaced by Ca, a large charge and discharge capacity (initial charge capacity 301 mAh / g, initial discharge capacity 223 mAh / g (1718 mAh / cc)) and a small volume change rate (less than 0.5%) are obtained.

[0041] The negative electrode active material contains M3Me2X7 as the main component (the component with the highest mass ratio), or may be substantially composed of M3Me2X7. On the other hand, in the negative electrode active material, other active materials such as intermetallic compounds other than M3Me2X7, carbon-based active materials such as graphite, or Si-based active materials containing Si may also be used in combination. For example, when graphite is used in combination, the content of graphite can be 50 to 90% by mass relative to the mass of the negative electrode active material.

[0042] The binder contained in the negative electrode mixture layer is an aqueous ammonium carboxymethylcellulose (NH4-CMC). Alternatively, it may contain styrene butadiene rubber (SBR). It should be noted that aqueous binders such as aqueous urethanes and aqueous acrylic polymers may also be used.

[0043] The mass ratio of the binder to the negative electrode active material is preferably 0.3 wt% or more and 5.0 wt% or less. The ratio of NH4-CMC to SBR is preferably about 2:0.5 to 2.

[0044] [Separator]

[0045] The separator 13 uses a porous sheet with ion permeability and insulation. Specific examples of the porous sheet include microporous membranes, woven fabrics, non-woven fabrics, and the like. Suitable materials for the separator 13 include olefin resins such as polyethylene and polypropylene, and cellulose. The separator 13 may be a single-layer structure or a laminated structure. A heat-resistant layer containing a heat-resistant material may be formed on the surface of the separator 13. Examples of the heat-resistant material include polyamide resins such as aliphatic polyamides and aromatic polyamides (aramids), polyimide resins such as polyamide-imide and polyimide, and the like.

[0046] <Example>

[0047] Hereinafter, the present disclosure will be further described based on examples, but the present disclosure is not limited to these examples.

[0048] [Production of negative electrode]

[0049] La3Ni2Sn7 with a particle size of 2 to 20 μm is used as the negative electrode active material, SBR / CMC is used as the binder, and artificial graphite SP5030 is used as the conductive material. La3Ni2Sn7 / NH4-CMC / SBR / SP5030 are mixed in a mass ratio of 85.5 / 3 / 1.5 / 10 to prepare a negative electrode mixture slurry. Next, the negative electrode mixture slurry is applied to the negative electrode core formed by copper foil, and the coating is dried and compressed, and then cut into the specified electrode size to obtain the negative electrode. It should be noted that as copper foil, a surface roughened copper foil with a thickness of about 18 μm can be used.

[0050] [Fabrication of test battery cells]

[0051] The negative electrode and the positive electrode formed of lithium metal foil are placed opposite each other with a separator interposed therebetween to form an electrode assembly, which is then housed in an outer can. A predetermined non-aqueous electrolyte is injected into the outer can and the outer can is sealed to obtain a bipolar battery cell (non-aqueous electrolyte secondary battery).

[0052] Here, the electrolyte solution was an EC / EMC solvent to which 1.0 M LiPF 6 was added as an electrolyte.

[0053] [Charge and discharge test (capacity evaluation)]

[0054] The resulting test cell was charged at a constant current (CC) of 0.2C at room temperature until the cell voltage reached 0.01V (the negative electrode potential was 0.01V relative to metallic lithium) and then discharged at 1.5V (the negative electrode potential was 1.5V relative to metallic lithium) to examine changes in electrode voltage. This cycle was then repeated with constant current discharge and constant current charging, and the charge and discharge capacities were measured during each cycle.

[0055] [result]

[0056] Figure 2 The X-ray diffraction patterns of electrodes from Comparative Example 1 using styrene butadiene rubber / sodium carboxymethyl cellulose (SBR / Na-CMC) as a binder, Comparative Example 2 using PAN as a binder, Comparative Example 3 using PI as a binder, and Comparative Example 4 using PVdF as a binder are shown, along with an example using styrene butadiene rubber / ammonium carboxymethyl cellulose (SBR / NH4-CMC) as a binder. The peaks indicated by triangles in the figures are peaks associated with impurity alloys (impurity alloys generated by unwanted alloying reactions). This indicates that no impurity alloy phases were generated in the examples using SBR / NH4-CMC.

[0057] Figure 3A and Figure 3B Graph showing the charge and discharge characteristics in Examples. Figure 3A is a graph showing the relationship between capacity and electrode potential. Figure 3B is a graph showing the relationship between the number of cycles and capacity.

[0058] As can be seen, the example using SBR / NH4-CMC as the negative electrode binder showed little degradation over three charge-discharge cycles. Furthermore, the charge-discharge curve showed minimal change over 29 charge-discharge cycles, maintaining 99.5% of the initial charge-discharge capacity, demonstrating excellent cycling characteristics.

[0059] Figure 4 This is a graph showing the charge and discharge characteristics of Comparative Example 1 using SBR / Na-CMC as the negative electrode binder. As can be seen, in Comparative Example 1, the capacity decreases due to repeated charge and discharge, and the cycle characteristics are poor. This is believed to be due to the generation of Figure 2 The alloying reaction is shown.

[0060] Table 1 shows the La3Ni2Sn7, La 1.8 Ca 1.2 Table showing the evaluation of various negative electrode active materials and binders for Ni2Sn7.

[0061] [Table 1]

[0062]

[0063] Thus, the negative electrode mixture layer contains La3Ni2Sn7, La 1.8 Ca 1.2 The results are the same for any of Ni2Sn7. That is, PVdF is easy to gel during coating, so it takes time to use (△ 1). The gelation during coating can be suppressed by adding maleic anhydride. Even if PAN does not use organic solvents, the cost of manufacturing becomes expensive (△ 2 Furthermore, PI and SBR / Na-CMC form an alloy during coating, which reduces the cycle characteristics (△ 3 ). Moreover, as an embodiment, SBR / NH4-CMC is aqueous, does not require an organic solvent, does not form an alloy, has good cycle characteristics, and is suitable as a binder (0).

[0064] For the negative electrode mixture layer containing a negative electrode active material represented by the general formula M3Me2X7 (wherein, M contains at least one member selected from the group consisting of La, Sr, Ca, Mg and Y, Me contains at least one member selected from the group consisting of Mn, Ni, Fe, Co and Cu, and X contains at least one member selected from the group consisting of Ge, Si, Sn, Al and B), it was confirmed that a binder containing ammonium carboxymethylcellulose (NH4-CMC) is suitable.

[0065] Thus, it can be seen that the negative electrode active material represented by the general formula M3Me2X7 (wherein M contains at least one member selected from the group consisting of La, Ce, Ba, Sr, Zr, Ca, Mg and Y, Me contains at least one member selected from the group consisting of Ti, V, Cr, Nb, Mn, Ni, Fe, Co and Cu, and X contains at least one member selected from the group consisting of Ge, Si, Sn, Al, P, Sb and B) is suitable as a binder containing carboxymethyl cellulose ammonium (NH4-CMC).

[0066] Description of Reference Numerals

[0067] 10 Secondary Batteries

[0068] 11. Positive electrode

[0069] 12 negative electrode

[0070] 13 Dividers

[0071] 14 Electrode body

[0072] 15 outer shell

[0073] 16 Sealing body

[0074] 17, 18 insulation board

[0075] 19 Positive lead

[0076] 20 Negative lead

[0077] 21 grooved part

[0078] 22 Metal plates with partial openings

[0079] 23 Lower valve body

[0080] 24 Insulation components

[0081] 25 Upper valve body

[0082] 26 Cover

[0083] 26a Opening

[0084] 27 gasket

Claims

1. A lithium-ion battery comprising: a positive electrode having a positive electrode mixture layer containing a positive electrode active material; and a negative electrode having a negative electrode mixture layer containing a negative electrode active material, wherein the lithium-ion battery is charged and discharged by lithium ions moving between the positive electrode and the negative electrode. The negative electrode mixture layer contains: A negative electrode active material represented by the general formula M3Me2X7, wherein M comprises at least one member selected from the group consisting of La, Ce, Ba, Sr, Zr, Ca, Mg, and Y, Me comprises at least one member selected from the group consisting of Ti, V, Cr, Nb, Mn, Ni, Fe, Co, and Cu, and X comprises at least one member selected from the group consisting of Ge, Si, Sn, Al, P, Sb, and B, and the particle size of the M3Me2X7 member as the negative electrode active material is 2 to 20 μm; and A binder comprising ammonium carboxymethylcellulose (NH4-CMC).

2. A lithium-ion battery comprising: a positive electrode having a positive electrode mixture layer containing a positive electrode active material; and a negative electrode having a negative electrode mixture layer containing a negative electrode active material, wherein the lithium-ion battery is charged and discharged by lithium ions moving between the positive electrode and the negative electrode. The negative electrode mixture layer contains: A negative electrode active material represented by the general formula M3Me2X7, wherein M comprises at least one member selected from the group consisting of La, Sr, Ca, Mg, and Y, Me comprises at least one member selected from the group consisting of Mn, Ni, Fe, Co, and Cu, and X comprises at least one member selected from the group consisting of Ge, Si, Sn, Al, and B, wherein the particle size of the M3Me2X7 member as the negative electrode active material is 2 to 20 μm; and A binder comprising ammonium carboxymethylcellulose (NH4-CMC). 3 . The lithium ion battery according to claim 1 , further comprising another aqueous binder as the binder.

4. The lithium ion battery according to claim 3, wherein The other water-based binder is styrene butadiene rubber (SBR).

5. The lithium ion battery according to claim 1 or 2, wherein The mass ratio of the binder to the negative electrode active material is 0.3 wt % or more and 5.0 wt % or less.

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