Non-aqueous secondary battery negative electrode and non-aqueous secondary battery using same

Abstract

This non-aqueous secondary battery negative electrode 60 comprises a negative electrode collector 6a and a negative electrode active material layer 6b that is carried on the negative electrode collector 6a. The negative electrode active material layer 6b includes active material particles and a plurality of types of organic polymers. The plurality of types of organic polymers include a straight-chain sulfur-containing polysaccharide and at least one other component that is different from the straight-chain sulfur-containing polysaccharide. The ratio of the mass of the straight-chain sulfur-containing polysaccharide to the total mass of the plurality of types of organic polymers is 20%–80%.

Description

Negative electrode for non-aqueous secondary battery and non-aqueous secondary battery using the same

[0001] The present disclosure relates to a negative electrode for a non-aqueous secondary battery and a non-aqueous secondary battery using the same.

[0002] Some electrodes in batteries, such as lithium secondary batteries, undergo large volume changes during charge and discharge. Large volume changes tend to occur when high-capacity active materials are used, and are one of the causes of deterioration in secondary battery performance during repeated charge and discharge.

[0003] The binder contained in the electrode provides flexibility to the electrode and prevents the deterioration of secondary battery performance due to volumetric changes in the electrode. Polymer materials are used as binders.

[0004] JP 2001-167755 A JP 2010-177060 A

[0005] In the prior art, there is a demand for improving the durability of electrodes against repeated charge and discharge.

[0006] The present disclosure provides a negative electrode for a non-aqueous secondary battery, comprising: a negative electrode current collector; and a negative electrode active material layer supported on the negative electrode current collector, wherein the negative electrode active material layer contains a negative electrode active material and a plurality of kinds of organic polymers, the plurality of kinds of organic polymers contain a linear sulfur-containing polysaccharide and at least one other component different from the linear sulfur-containing polysaccharide, and a ratio of the mass of the linear sulfur-containing polysaccharide to the total mass of the plurality of kinds of organic polymers is 20% or more and 80% or less.

[0007] According to the technology of the present disclosure, it is possible to improve the durability of the electrode against repeated charge and discharge.

[0008] 1 is a cross-sectional view of a negative electrode for a non-aqueous secondary battery according to a first embodiment of the present disclosure. FIG 2 is a cross-sectional view of a non-aqueous secondary battery according to a second embodiment of the present disclosure.

[0009] Hereinafter, embodiments of the present disclosure will be described with reference to the drawings. The present disclosure is not limited to the following embodiments.

[0010] 1 is a cross-sectional view of a negative electrode for a non-aqueous secondary battery according to a first embodiment of the present disclosure. The negative electrode 6 for a non-aqueous secondary battery has a negative electrode current collector 6 a and a negative electrode active material layer 6 b. The negative electrode active material layer 6 b is supported on the negative electrode current collector 6 a. Hereinafter, the negative electrode 6 for a non-aqueous secondary battery may be simply referred to as the "negative electrode 6."

[0011] The negative electrode active material layer 6b contains a negative electrode active material and multiple types of organic polymers. The multiple types of organic polymers are dispersed in the negative electrode active material layer 6b and serve as binders in the negative electrode active material layer 6b. The multiple types of organic polymers contain a linear sulfur-containing polysaccharide and at least one other component different from the linear sulfur-containing polysaccharide. The ratio of the mass of the linear sulfur-containing polysaccharide to the total mass of the multiple types of organic polymers is 20% or more and 80% or less. By combining the linear sulfur-containing polysaccharide with the at least one other component, the durability of the negative electrode 6 against repeated charge and discharge is improved. The improved durability of the negative electrode 6 is reflected in the capacity retention rate during charge and discharge cycles of a battery using the negative electrode 6.

[0012] The reason why the combination of a linear sulfur-containing polysaccharide and at least one other component improves the durability of the negative electrode 6 is not entirely clear, but it can be considered as follows. That is, when one component of the binder contains sulfur atoms, a strong interaction occurs between that component (the linear sulfur-containing polysaccharide) and at least one other component. The strong interaction between different organic polymers effectively prevents deterioration of contact between the negative electrode active material layer 6b and the negative electrode current collector 6a or between materials contained in the negative electrode active material layer 6b, even if the negative electrode active material layer 6b expands and contracts during charge and discharge. It is presumed that this improves the durability of the negative electrode 6.

[0013] If the above-mentioned effect is achieved by the linear polysaccharide containing sulfur atoms, it is thought that the higher the ratio of the linear sulfur-containing polysaccharide, the greater the effect. However, if the ratio of the linear sulfur-containing polysaccharide is too high, the fluidity of the slurry decreases, making it difficult to uniformly apply the slurry to the negative electrode current collector 6a. If the ratio of the linear sulfur-containing polysaccharide is too low, the above-mentioned effect cannot be fully achieved. By adjusting the ratio of the linear sulfur-containing polysaccharide to 20% or more and 80% or less, it is possible to avoid difficulties in manufacturing the negative electrode 6 while improving the durability of the negative electrode 6. The ratio of the mass of the linear sulfur-containing polysaccharide to the total mass of the plurality of organic polymers may be 30% or more and 70% or less.

[0014] The linear sulfur-containing polysaccharide is a linear polysaccharide containing sulfur atoms. The linear sulfur-containing polysaccharide may have a sulfate group. When the linear sulfur-containing polysaccharide has a sulfate group, a strong interaction can be expected between the linear sulfur-containing polysaccharide and at least one other component.

[0015] The linear sulfur-containing polysaccharide may include carrageenan. Carrageenan is a linear polysaccharide having a sulfate group. Carrageenan is expected to promote a strong interaction between the linear sulfur-containing polysaccharide and at least one other component.

[0016] The at least one other component different from the linear sulfur-containing polysaccharide may be a component represented by a structural formula different from that of the linear sulfur-containing polysaccharide. The at least one other component may include a polysaccharide having no anionic functional groups. This configuration can prevent electrostatic repulsion between the linear sulfur-containing polysaccharide and the at least one other component. Examples of anionic functional groups include a carboxyl group, a carboxymethyl group, a sulfonic acid group, a sulfate group, a phosphate ester group, and a nitro group. Specifically, the at least one other component may be a polysaccharide having no sulfate groups.

[0017] The ratio of the mass of the at least one other component to the total mass of the plurality of organic polymers is, for example, 20% or more and 80% or less.

[0018] The at least one other component may include galactomannan. That is, the at least one other component may be a component belonging to the galactomannan family. Galactomannan is a polysaccharide extracted from a legume, and is composed of a β-D-mannose main chain and an α-D-galactose side chain. The ratio of mannose to galactose varies depending on the raw material. Examples of galactomannans include fenugreek gum, guar gum, tara gum, locust bean gum, and cassia gum. At least one selected from these can be used as the at least one other component. Since a strong interaction can be expected between the linear sulfur-containing polysaccharide and the galactomannan, the use of galactomannan is expected to significantly improve the durability of the negative electrode 6.

[0019] The galactomannan may contain locust bean gum. It is presumed that the effect of improving the durability of the negative electrode 6 is further enhanced by a specific interaction between the locust bean gum and the linear sulfur-containing polysaccharide (particularly, carrageenan).

[0020] The ratio of the mass of the linear sulfur-containing polysaccharide to the mass of the galactomannan is, for example, 30% or more. By appropriately adjusting this ratio, it is expected that the durability of the negative electrode 6 will be further improved. In the negative electrode 6, the content of the linear sulfur-containing polysaccharide preferably exceeds the content of the galactomannan on a mass basis. With such a configuration, it is expected that the durability of the negative electrode 6 will be further improved. There is no particular upper limit to the ratio of the mass of the linear sulfur-containing polysaccharide to the mass of the galactomannan. The linear sulfur-containing polysaccharide may be contained in the negative electrode 6 in an amount up to 19 times, preferably up to 9 times, and more preferably up to 5.7 times the amount of the galactomannan on a mass basis.

[0021] The ratio of the mass of the galactomannan to the total mass of the multiple organic polymers is, for example, 5% or more and less than 50%. Of the ratios of the mass of each organic polymer to the total mass of the multiple organic polymers, it is desirable that the mass ratio of the galactomannan be the smallest. With this configuration, it is expected that the durability of the negative electrode 6 will be further improved.

[0022] At least one other component may contain cellulose. Cellulose has a role of adjusting the viscosity of the multiple organic polymers serving as a binder. When at least one other component contains cellulose, the viscosity of the multiple organic polymers decreases, making it easier to apply the slurry for forming the negative electrode active material layer 6 b to the negative electrode current collector 6 a.

[0023] Examples of cellulose include carboxymethyl cellulose, methyl cellulose, ethyl cellulose, isopropyl cellulose, hydroxymethyl cellulose, hydroxyethyl cellulose, hydroxypropyl cellulose, hydroxypropylmethyl cellulose, cyanoethyl cellulose, and ethyl-hydroxyethyl cellulose. At least one selected from these can be used as at least one other component. In particular, carboxymethyl cellulose contributes to improving the dispersibility of solid particles such as active material particles in the slurry.

[0024] The ratio of the mass of cellulose to the total mass of the multiple organic polymers is, for example, 20% or more and 80% or less, preferably 40% or more and 70% or less. When at least one other component is cellulose, the ratio of the mass of cellulose to the total mass of the multiple organic polymers is preferably equal to or greater than the ratio of the mass of the linear sulfur-containing polysaccharide to the total mass of the multiple organic polymers. Furthermore, when the multiple organic polymers include three or more organic polymers, cellulose may be contained in the multiple organic polymers in the largest amount in terms of mass ratio. When the multiple organic polymers include three or more organic polymers, the ratio of the mass of cellulose to the total mass of the multiple organic polymers is preferably equal to or greater than the ratio of the mass of the other organic polymers to the multiple organic polymers. This stabilizes the fluidity of the slurry, making it easier to uniformly apply the slurry to the negative electrode current collector 6a.

[0025] The at least one other component may include galactomannan and cellulose. In one example, the multiple organic polymers may include or consist of carrageenan, galactomannan, and cellulose. The combination of carrageenan, galactomannan, and cellulose can provide the multiple effects described above in a superimposed manner.

[0026] The negative electrode active material contained in the negative electrode active material layer 6b is, for example, graphite, elemental silicon, SiO x , composite materials containing silicon and carbon, SiO x and carbon, and a composite material containing silicon and a metal silicate. x satisfies 0.5≦x≦1.5. The composite material containing silicon and carbon may be a material in which particles of elemental silicon are dispersed in a carbon matrix. x The composite material containing carbon is a carbon matrix containing SiO xThe composite material containing silicon and a metal silicate may be a material in which particles of elemental silicon are dispersed in a metal silicate matrix. The metal silicate is, for example, lithium silicate. These materials expand and contract as the battery is charged and discharged. Therefore, when the technology of the present disclosure is applied to a negative electrode 6 containing these materials as active materials, the effect of improving the durability of the negative electrode 6 is further enhanced.

[0027] The negative electrode active material layer 6b may further contain a conductive additive. Examples of the conductive additive include carbon materials and conductive polymers. Examples of the carbon material include carbon black, graphite, acetylene black, carbon nanotubes, carbon nanofibers, graphene, fullerene, and graphite oxide. Examples of the conductive polymer include polyaniline, polypyrrole, and polythiophene. At least one selected from these conductive additives can be used.

[0028] The negative electrode current collector 6a is a foil made of a metal material such as stainless steel, nickel, a nickel alloy, copper, or a copper alloy.

[0029] (Embodiment 2) FIG. 2 is a cross-sectional view of a nonaqueous secondary battery according to embodiment 2 of the present disclosure. The nonaqueous secondary battery 100 includes a container 1 and an electrode group 4. The electrode group 4 has a wound structure. The electrode group 4 is housed in the container 1. The electrode group 4 includes a positive electrode 5, a negative electrode 6, and a pair of separators 7. The electrode group 4 is impregnated with an electrolyte. The opening of the container 1 is closed with a sealing plate 2. The positive electrode 5 includes a positive electrode current collector 5a and a positive electrode active material layer 5b. One end of a positive electrode lead 5c is connected to the positive electrode 5. The other end of the positive electrode lead 5c is connected to the back surface of the sealing plate 2. An insulating gasket 3 is disposed around the periphery of the sealing plate 2. The negative electrode 6 includes a negative electrode current collector 6a and a negative electrode active material layer 6b. One end of a negative electrode lead 6c is connected to the negative electrode 6. The other end of the negative electrode lead 6c is connected to the bottom surface of the container 1. Insulating rings 8 are disposed on the upper and lower surfaces of the electrode group 4. In this embodiment, the container 1 has the polarity of the negative electrode 6, and the sealing plate 2 has the polarity of the positive electrode 5. However, the container 1 may have the polarity of the positive electrode 5, and the sealing plate 2 may have the polarity of the negative electrode 6.

[0030] By using the negative electrode 6 described in the first embodiment, the capacity retention rate of the nonaqueous secondary battery 100 can be improved.

[0031] Examples of the non-aqueous secondary battery 100 include a lithium secondary battery, a sodium secondary battery, a magnesium secondary battery, etc. The non-aqueous secondary battery 100 is typically a lithium secondary battery.

[0032] The positive electrode current collector 5a is a foil made of a metal material such as aluminum, an aluminum alloy, stainless steel, titanium, or a titanium alloy.

[0033] The positive electrode active material layer 5b is supported on the positive electrode current collector 5a. The positive electrode active material layer 5b includes a positive electrode active material. Examples of the positive electrode active material include lithium-containing transition metal oxides, lithium-containing transition metal phosphates, transition metal fluorides, polyanionic materials, fluorinated polyanionic materials, transition metal sulfides, transition metal oxysulfides, and transition metal oxynitrides. In particular, using a lithium-containing transition metal oxide or a lithium-containing transition metal phosphate as the positive electrode active material can reduce the manufacturing cost of the battery and increase the average discharge voltage. Examples of lithium-containing transition metal oxides include lithium cobalt oxide, lithium nickel cobalt aluminum oxide, lithium nickel cobalt manganese oxide, and lithium nickel manganese oxide. Examples of lithium-containing transition metal phosphates include lithium iron phosphate, lithium vanadium phosphate, lithium cobalt phosphate, and lithium nickel phosphate.

[0034] The positive electrode active material layer 5b may contain other materials such as a conductive additive and a binder.

[0035] The conductive additive is used to reduce the resistance of the positive electrode 5. Examples of the conductive additive include the materials described above.

[0036] The binder is used to improve the binding property of the material constituting the positive electrode 5. As the binder, polymer materials such as polyvinylidene fluoride, vinylidene fluoride-hexafluoropropylene copolymer, vinylidene fluoride-tetrafluoroethylene copolymer, polytetrafluoroethylene, carboxymethyl cellulose, polyacrylic acid, styrene-butadiene copolymer rubber, polypropylene, polyethylene, and polyimide can be used.

[0037] The electrolyte is a non-aqueous electrolyte impregnated into the positive electrode 5, the negative electrode 6, and the separator 7. The electrolyte may fill the internal space of the container 1. The electrolyte allows lithium ions to move between the positive electrode 5 and the negative electrode 6.

[0038] The electrolyte solution contains a non-aqueous solvent and a lithium salt.

[0039] Examples of the non-aqueous solvent include cyclic carbonates, chain carbonates, cyclic ethers, chain ethers, nitriles, amides, etc. One selected from these solvents may be used, or two or more may be used in combination.

[0040] Examples of lithium salts include lithium hexafluorophosphate (LiPF), lithium tetrafluoroborate (LiBF), lithium perchlorate (LiClO), lithium bis(fluorosulfonyl)imide (LiFSI), lithium bis(trifluoromethanesulfonyl)imide (LiTFSI), lithium bisperfluoroethylsulfonylimide (LiN(SO2C2F5)2), LiAsF6, LiCF3SO3, and lithium difluoro(oxalato)borate. One selected from these lithium salts may be used, or two or more may be used in combination.

[0041] The separator 7 has lithium ion conductivity. The material of the separator 7 is not particularly limited as long as it allows the passage of lithium ions. The material of the separator 7 can be at least one selected from the group consisting of a gel electrolyte, an ion exchange resin membrane, a semipermeable membrane, and a porous membrane. If the separator 7 is made of these materials, the safety of the nonaqueous secondary battery 100 can be sufficiently ensured. Examples of gel electrolytes include gel electrolytes containing fluororesins such as PVdF. Examples of ion exchange resin membranes include cation exchange membranes and anion exchange membranes. Examples of porous membranes include porous membranes made of polyolefin resins and porous membranes containing glass paper obtained by weaving glass fibers into nonwoven fabric.

[0042] The container 1 is made of a metal such as aluminum or stainless steel, and may have a cylindrical shape or a rectangular tube shape.

[0043] The electrode group 4 may be wound into a cylindrical shape or an oval shape.

[0044] The shape of the nonaqueous secondary battery 100 is not limited to a cylindrical shape, and various shapes such as a coin shape, a square shape, a sheet shape, a button shape, a flat shape, and a laminated shape can be adopted as the shape of the nonaqueous secondary battery 100.

[0045] (Other Embodiments) (Additional Notes) The above description of the embodiments discloses the following techniques.

[0046] (Technology 1) A negative electrode for a non-aqueous secondary battery, comprising: a negative electrode current collector; and a negative electrode active material layer supported on the negative electrode current collector, wherein the negative electrode active material layer contains a negative electrode active material and a plurality of kinds of organic polymers, the plurality of kinds of organic polymers contain a linear sulfur-containing polysaccharide and at least one other component different from the linear sulfur-containing polysaccharide, and a ratio of the mass of the linear sulfur-containing polysaccharide to the total mass of the plurality of kinds of organic polymers is 20% or more and 80% or less.

[0047] (Technology 2) The negative electrode for a non-aqueous secondary battery according to Technology 1, wherein the at least one other component includes a polysaccharide having no anionic functional group.

[0048] (Technology 3) The negative electrode for a non-aqueous secondary battery according to Technology 1 or 2, wherein the at least one other component includes galactomannan.

[0049] (Technology 4) The negative electrode for a non-aqueous secondary battery according to Technology 3, wherein the galactomannan contains locust bean gum.

[0050] (Technology 5) The negative electrode for a non-aqueous secondary battery according to Technology 3 or 4, wherein the ratio of the mass of the linear sulfur-containing polysaccharide to the mass of the galactomannan is 30% or more.

[0051] (Technology 6) The negative electrode for a non-aqueous secondary battery according to any one of Technologies 3 to 5, wherein the content of the linear sulfur-containing polysaccharide exceeds the content of the galactomannan.

[0052] (Technology 7) The negative electrode for a nonaqueous secondary battery according to any one of Technologies 3 to 6, wherein the mass ratio of the galactomannan is the smallest among the mass ratios of each organic polymer to the total mass of the plurality of organic polymers.

[0053] (Technology 8) The negative electrode for a non-aqueous secondary battery according to any one of Technologies 1 to 7, wherein the linear sulfur-containing polysaccharide has a sulfate group.

[0054] (Technology 9) The negative electrode for a non-aqueous secondary battery according to any one of Techniques 1 to 8, wherein the linear sulfur-containing polysaccharide includes carrageenan.

[0055] (Technology 10) The negative electrode for a non-aqueous secondary battery according to any one of Technologies 1 to 9, wherein the at least one other component includes cellulose.

[0056] (Technology 11) The negative electrode for a nonaqueous secondary battery according to any one of Technologies 1 to 9, wherein the at least one other component is cellulose, and a ratio of a mass of the cellulose to a total mass of the plurality of kinds of organic polymers is equal to or greater than a ratio of a mass of the linear sulfur-containing polysaccharide to a total mass of the plurality of kinds of organic polymers.

[0057] (Technology 12) The negative electrode active material is selected from the group consisting of graphite, a composite material containing silicon and carbon, silicon, and SiO x , and SiO xand carbon, and x satisfies 0.5≦x≦1.5.

[0058] (Technology 13) A non-aqueous secondary battery having the negative electrode for a non-aqueous secondary battery according to any one of Technologies 1 to 12.

[0059] [Example 1] (Preparation of positive electrode) LiNi 0.8 Mn 0.2 A positive electrode slurry was prepared by mixing and stirring a positive electrode active material having a composition of O, acetylene black (AB), polyvinylidene fluoride (PVDF), and N-methyl-pyrrolidone (NMP). The mass ratio of the positive electrode active material, AB, and PVDF was positive electrode active material:AB:PVDF=96:2:2. The positive electrode slurry was applied to the surface of aluminum foil to form a coating film, which was then dried and rolled. This resulted in a positive electrode common to the examples and comparative examples.

[0060] (Preparation of Negative Electrode) Carrageenan, carboxymethyl cellulose (CMC), and water were mixed and stirred to prepare a binder solution. The mass ratio of carrageenan to CMC was carrageenan:CMC = 50:50. Graphite, a silicon-carbon composite (SiC), carbon nanotubes (CNT), and the binder solution were mixed and stirred to prepare a negative electrode slurry. The mass ratio of graphite, SiC, CNT, and binder was graphite:SiC:CNT:binder = 78:19:0.1:2.9. The mass of the binder was the total mass of carrageenan and CMC. The negative electrode slurry was applied to the surface of copper foil to form a coating film, which was then dried and rolled. This produced the negative electrode of Example 1.

[0061] (Fabrication of Battery) Current collecting leads were attached to the common positive electrode and the negative electrode of Example 1. The common positive electrode, separator, and negative electrode of Example 1 were combined and placed in a container made of laminate film. An electrolyte solution was poured into the container and sealed. This resulted in the battery of Example 1. A separator having a three-layer structure of polypropylene / polyethylene / polypropylene was used. The electrolyte solution was prepared by dissolving lithium hexafluorophosphate at a concentration of 1 mol / L in a mixed solvent of ethylene carbonate, ethyl methyl carbonate, and dimethyl carbonate.

[0062] [Example 2] A binder solution was prepared by mixing and stirring carrageenan, locust bean gum (LBG), CMC, and water. The mass ratio of carrageenan, LBG, and CMC was carrageenan:LBG:CMC = 40:10:50. Except for using this binder solution, a negative electrode of Example 2 was fabricated in the same manner as Example 1. A battery of Example 2 was fabricated in the same manner as Example 1 using the negative electrode of Example 2.

[0063] Comparative Example 1 A binder solution was prepared by mixing and stirring carrageenan, LBG, CMC, and water. The mass ratio of carrageenan, LBG, and CMC was carrageenan:LBG:CMC = 10:40:50. Except for using this binder solution, a negative electrode of Comparative Example 1 was fabricated in the same manner as in Example 1. A battery of Comparative Example 1 was fabricated in the same manner as in Example 1 using the negative electrode of Comparative Example 1.

[0064] Comparative Example 2 A binder solution was prepared by mixing and stirring LBG, CMC, and water. The mass ratio of LBG to CMC was LBG:CMC = 50:50. Except for using this binder solution, a negative electrode of Comparative Example 2 was fabricated in the same manner as in Example 1. A battery of Comparative Example 2 was fabricated in the same manner as in Example 1 using the negative electrode of Comparative Example 2.

[0065] [Cycle Test] A cycle test was performed on the batteries of the Examples and Comparative Examples as follows. The batteries were placed in a thermostatic chamber at 25°C. The batteries were charged at a current value of 0.3 C until an upper limit voltage of 4.4 V was reached. Next, the batteries were discharged at a current value of 0.5 C until a lower limit voltage of 2.5 V was reached. This charge / discharge cycle was repeated 100 times. However, the current value during discharge was set to 0.2 C during the 50th and 100th charge / discharge cycles. The ratio of the discharge capacity at the 98th discharge to the discharge capacity at the first discharge was calculated as the capacity retention rate (%). The results are shown in Table 1.

[0066]

[0067] The numerical values ​​in each item in Table 1 represent the ratio of the mass of carrageenan to the total mass of the binder, the ratio of the mass of locust bean gum to the total mass of the binder, and the ratio of the mass of carboxymethyl cellulose to the total mass of the binder, expressed as a percentage.

[0068] As shown in Table 1, the capacity retention rates of the batteries of Examples 1 and 2 were higher than those of the batteries of Examples 1 to 3.

[0069] As can be seen from the results of Example 2 and Comparative Example 1, when the ratio of the mass of carrageenan to the total mass of the binder was too low, the effect of improving the capacity retention rate was not obtained. By adjusting the ratio of carrageenan to an appropriate range, the effect of improving the capacity retention rate was obtained.

[0070] As can be seen from the results of Examples 1 and 2, the use of locust bean gum was not essential for achieving the effect of improving the capacity retention rate.

[0071] As can be seen from the results of Example 2, the effect of improving the capacity retention rate was maximized by combining the three components of carrageenan, locust bean gum, and carboxymethyl cellulose and appropriately adjusting the mass ratio of carrageenan. The battery of Example 2 also had a high average discharge voltage.

[0072] The technology of the present disclosure is useful for non-aqueous secondary batteries such as lithium secondary batteries.

Claims

1. A negative electrode for a non-aqueous secondary battery, comprising: a negative electrode current collector; and a negative electrode active material layer supported on the negative electrode current collector, wherein the negative electrode active material layer contains a negative electrode active material and multiple types of organic polymers, the multiple types of organic polymers contain a linear sulfur-containing polysaccharide and at least one other component different from the linear sulfur-containing polysaccharide, and a ratio of the mass of the linear sulfur-containing polysaccharide to a total mass of the multiple types of organic polymers is 20% or more and 80% or less.

2. The negative electrode for a non-aqueous secondary battery according to claim 1, wherein the at least one other component comprises a polysaccharide having no anionic functional group.

3. The negative electrode for a non-aqueous secondary battery according to claim 1, wherein the at least one other component comprises a galactomannan.

4. The negative electrode for a non-aqueous secondary battery according to claim 3, wherein the galactomannan comprises locust bean gum.

5. The negative electrode for a non-aqueous secondary battery according to claim 3, wherein a ratio of a mass of said linear sulfur-containing polysaccharide to a mass of said galactomannan is 30% or more.

6. The negative electrode for a non-aqueous secondary battery according to claim 3, wherein a content of the linear sulfur-containing polysaccharide exceeds a content of the galactomannan.

7. The negative electrode for a nonaqueous secondary battery according to claim 3, wherein, among the ratios of the mass of each organic polymer to the total mass of the plurality of organic polymers, the ratio of the mass of the galactomannan is the smallest.

8. The negative electrode for a non-aqueous secondary battery according to claim 1, wherein the linear sulfur-containing polysaccharide has a sulfate group.

9. The negative electrode for a non-aqueous secondary battery according to claim 1, wherein the linear sulfur-containing polysaccharide comprises carrageenan.

10. The negative electrode for a non-aqueous secondary battery according to claim 1, wherein the at least one other component comprises cellulose.

11. The negative electrode for a non-aqueous secondary battery according to claim 1, wherein the at least one other component comprises cellulose, and a ratio of a mass of the cellulose to a total mass of the plurality of kinds of organic polymers is equal to or greater than a ratio of a mass of the linear sulfur-containing polysaccharide to a total mass of the plurality of kinds of organic polymers.

12. The negative electrode active material is selected from the group consisting of graphite, a composite material containing silicon and carbon, silicon, and SiO x , and SiO x and carbon, and x satisfies 0.5≦x≦1.

5. The negative electrode for a non-aqueous secondary battery according to claim 1 .

13. A non-aqueous secondary battery comprising the negative electrode for a non-aqueous secondary battery according to any one of claims 1 to 12.