JP5187551B2 - Negative electrode for lithium ion secondary battery and lithium ion secondary battery - Google Patents

Description

The present invention is a lithium-ion secondary battery negative electrode active material layer is provided on the anode current collector, and a lithium ion secondary battery having the same.

  In recent years, portable electronic devices such as camera-integrated VTRs (video tape recorders), digital still cameras, mobile phones, personal digital assistants, and notebook computers have become widespread, and there is a strong demand for miniaturization, weight reduction, and long life. It has been. Accordingly, as a power source for portable electronic devices, development of a battery, in particular, a secondary battery that is lightweight and capable of obtaining a high energy density is underway.

  Among them, secondary batteries that use the insertion and extraction of lithium for charge / discharge reactions (so-called lithium ion secondary batteries) are highly expected because they provide a higher energy density than lead batteries and nickel cadmium batteries. . In this lithium ion secondary battery, a carbon material is widely used as an active material for the negative electrode (negative electrode active material).

Recently, with the improvement in performance of portable electronic devices, further improvement in capacity has been demanded, and the use of tin or silicon as a negative electrode active material instead of a carbon material has been studied (for example, Patent Documents). 1 and 2). This is because the theoretical capacity of tin (994 mAh / g) and the theoretical capacity of silicon (4199 mAh / g) are much larger than the theoretical capacity of graphite (372 mAh / g), so that a significant improvement in battery capacity can be expected.
U.S. Pat. No. 4,950,566 International Publication No. WO01 / 031724 Pamphlet

However, when tin, silicon, or the like is used as the negative electrode active material, a large volume change occurs with the insertion and extraction of lithium ions. For this reason, when the binding performance of the binder is insufficient, the utilization factor of the active material is reduced by repeating charging and discharging, and as a result, the cycle characteristics are deteriorated. In order to solve such a problem, an example in which a salt (monomer) of polyacrylic acid or polymaleic acid is used as a binder has been reported (for example, see Patent Documents 3 and 4).
JP 2006-196339 A JP 2006-210208 A

  However, recent portable electronic devices are becoming more sophisticated and multifunctional, and power consumption is increasing accordingly. Therefore, charging and discharging of secondary batteries tend to be repeated more frequently. For this reason, even when polyacrylic acid or a salt (monomer) of polymaleic acid is used as a binder, it is difficult to obtain sufficient cycle characteristics. Therefore, further improvement is desired regarding the cycle characteristics of the secondary battery.

The present invention has been made in view of the above problems, and its object is to provide a lithium ion secondary battery comprising a lithium-ion secondary battery negative electrode capable of improving the cycle characteristics, and it is there.

The negative electrode for a lithium ion secondary battery of the present invention includes a negative electrode active material containing at least one of a simple substance, an alloy and a compound of silicon, and a simple substance, an alloy and a compound of tin, and poly (lithium styrenesulfonate-maleic). An anode active material layer containing a diacid lithium) copolymer or a poly (sodium styrenesulfonate-disodium maleate) copolymer is provided on the anode current collector. Moreover, the lithium ion secondary battery of this invention is equipped with electrolyte solution with said negative electrode for lithium ion secondary batteries, and a positive electrode.

In the negative electrode for lithium ion secondary batteries and the lithium ion secondary battery of the present invention, the negative electrode is made of a poly (lithium styrenesulfonate-dilithium maleate) copolymer or a poly (sodium styrenesulfonate-disodium maleate) copolymer. Since the active material is sufficiently bound, it is difficult for the negative electrode active material itself to be pulverized and the negative electrode active material to be removed from the negative electrode current collector during charge and discharge.

According to the negative electrode for lithium ion secondary batteries and the lithium ion secondary battery of the present invention, the negative electrode active material layer contains at least one of a simple substance of silicon, an alloy and a compound, and a simple substance of tin, an alloy and a compound of tin. Since the poly (lithium styrenesulfonate-dilithium maleate) copolymer or the poly (sodium styrenesulfonate-disodium maleate) copolymer is included together with the negative electrode active material, the negative electrode active material during charge / discharge It is possible to suppress pulverization of itself and dropping of the negative electrode active material from the negative electrode current collector, and to improve conductivity between the negative electrode current collector and the negative electrode active material. As a result, cycle characteristics can be improved.

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

  FIG. 1 shows a cross-sectional configuration of a negative electrode according to an embodiment of the present invention. The negative electrode is used for an electrochemical device such as a battery, and includes a negative electrode current collector 1 and a negative electrode active material layer 2 provided on the negative electrode current collector 1.

  The negative electrode current collector 1 is preferably made of a material having good electrochemical stability, electrical conductivity, and mechanical strength. Examples of this material include metal materials such as copper (Cu), nickel (Ni), and stainless steel. Among these, copper is preferable. This is because high electrical conductivity can be obtained.

  The negative electrode active material layer 2 includes a negative electrode material capable of occluding and releasing an electrode reactant as a negative electrode active material, and a binder. Furthermore, a conductive agent may be included as necessary. The negative electrode active material layer 2 may be provided on both sides of the negative electrode current collector 1 or may be provided on one side.

  The negative electrode material capable of occluding and releasing the electrode reactive substance here includes at least one of silicon and tin. That is, it is a material having at least a part of a simple substance, an alloy or a compound of silicon, a simple substance, an alloy or a compound of tin, or one or more phases thereof. These may be used alone or in combination of two or more. Such a negative electrode material has a high ability to occlude and release electrode reactants, so that a high energy density is easily obtained.

  Examples of the negative electrode material containing a simple substance of silicon include a material mainly containing a simple substance of silicon. The negative electrode active material layer 2 containing this negative electrode material has, for example, a structure in which oxygen (O) and a second constituent element other than silicon exist between the silicon simple substance layers. The total content of silicon and oxygen in the negative electrode active material layer 2 is preferably 50% by mass or more, and in particular, the content of silicon alone is preferably 50% by mass or more. Examples of the second constituent element other than silicon include titanium (Ti), chromium (Cr), manganese (Mn), iron, cobalt (Co), nickel, copper, zinc, indium, silver, magnesium (Mg), Examples thereof include aluminum, germanium, tin, bismuth, and antimony (Sb). The negative electrode active material layer 2 containing a material mainly composed of a simple substance of silicon can be formed, for example, by co-evaporation of silicon and other constituent elements.

As an alloy of silicon, for example, as a second constituent element other than silicon, among the group consisting of tin, nickel, copper, iron, cobalt, manganese, zinc, indium, silver, titanium, germanium, bismuth, antimony and chromium The thing containing at least 1 sort (s) of these is mentioned. Examples of the silicon compound include those containing oxygen or carbon (C), and may contain the second constituent element described above in addition to silicon. Examples of silicon alloys or compounds include SiB ₄ , SiB ₆ , Mg ₂ Si, Ni ₂ Si, TiSi ₂ , MoSi ₂ , CoSi ₂ , NiSi ₂ , CaSi ₂ , CrSi ₂ , Cu ₅ Si, FeSi ₂ , MnSi. ₂ , NbSi ₂ , TaSi ₂ , VSi ₂ , WSi ₂ , ZnSi ₂ , SiC, Si ₃ N ₄ , Si ₂ N ₂ O, SiO _v (0 <v ≦ 2), SnO _w (0 <w ≦ 2) or LiSiO etc. are mentioned.

As an alloy of tin, for example, as a second constituent element other than tin, among the group consisting of silicon, nickel, copper, iron, cobalt, manganese, zinc, indium, silver, titanium, germanium, bismuth, antimony and chromium The thing containing at least 1 sort (s) of these is mentioned. Examples of the tin compound include those containing oxygen or carbon, and may contain the second constituent element described above in addition to tin. Examples of tin alloys or compounds include SnSiO ₃ , LiSnO, Mg ₂ Sn, and the like.

  In particular, as a negative electrode material containing at least one of silicon and tin, for example, a material containing tin as a first constituent element and a second constituent element and a third constituent element in addition to the tin is used. preferable. This is because the cycle characteristics are improved by including the second element and the third element. The second constituent element is cobalt, iron, magnesium, titanium, vanadium (V), chromium, manganese, nickel, copper, zinc, gallium, zirconium, niobium (Nb), molybdenum (Mo), silver, indium, cerium ( Ce), hafnium, tantalum (Ta), tungsten (W), bismuth and silicon. The third constituent element is at least one selected from the group consisting of boron, carbon, aluminum, and phosphorus (P).

  Among them, tin, cobalt and carbon are included as constituent elements, the carbon content is 9.9 mass% or more and 29.7 mass% or less, and the ratio of cobalt to the total of tin and cobalt (Co / (Sn + Co)) is 30 mass. An SnCoC-containing material that is not less than 70% and not more than 70% by mass is preferable. This is because a high energy density can be obtained in such a composition range.

  This SnCoC-containing material may further contain other constituent elements as necessary. As other constituent elements, for example, silicon, iron, nickel, chromium, indium, niobium, germanium, titanium, molybdenum, aluminum, phosphorus, gallium, or bismuth are preferable, and two or more of them may be included. This is because a higher effect can be obtained.

  The SnCoC-containing material has a phase containing tin, cobalt and carbon, and the phase preferably has a low crystallinity or an amorphous structure. In the SnCoC-containing material, it is preferable that at least a part of carbon as a constituent element is bonded to a metal element or a metalloid element as another constituent element. This is because aggregation or crystallization of tin or the like is suppressed.

  The SnCoC-containing material can be formed by, for example, melting a mixture obtained by mixing raw materials of each constituent element in an electric furnace, a high-frequency induction furnace, an arc melting furnace, or the like and then solidifying the mixture. It can also be formed by various atomization methods such as gas atomization or water atomization, various roll methods, methods utilizing mechanochemical reactions such as mechanical alloying methods and mechanical milling methods. Among these, a method using a mechanochemical reaction is preferable. This is because the negative electrode active material has a low crystallinity or an amorphous structure. In the method using the mechanochemical reaction, for example, a production apparatus such as a planetary ball mill apparatus or an attritor can be used.

  Moreover, as a measuring method for examining the bonding state of elements, for example, X-ray photoelectron spectroscopy (XPS) can be cited. In this XPS, in the apparatus calibrated so that the 4f orbit (Au4f) peak of gold atom is obtained at 84.0 eV, the peak of 1s orbit (C1s) of carbon appears at 284.5 eV in the case of graphite. . Moreover, if it is surface contamination carbon, it will appear at 284.8 eV. On the other hand, when the charge density of the carbon element is high, for example, when carbon is bonded to a metal element or a metalloid element, the peak of C1s appears in a region lower than 284.5 eV. That is, when the peak of the synthetic wave of C1s obtained for the SnCoC-containing material appears in a region lower than 284.5 eV, at least a part of the carbon contained in the SnCoC-containing material is a metal element or a half of other constituent elements. Combined with metal elements.

  In XPS, for example, the peak of C1s is used to correct the energy axis of the spectrum. Usually, since surface-contaminated carbon exists on the surface, the C1s peak of the surface-contaminated carbon is set to 284.8 eV, which is used as an energy standard. In XPS, the waveform of the peak of C1s is obtained as a form including the peak of surface contamination carbon and the peak of carbon in the SnCoC-containing material. For example, by analyzing using commercially available software, the surface contamination The carbon peak and the carbon peak in the SnCoC-containing material are separated. In the waveform analysis, the position of the main peak existing on the lowest bound energy side is used as the energy reference (284.8 eV).

  The negative electrode active material layer 2 using, as a negative electrode material, a simple substance of silicon, an alloy or compound, a simple substance of tin, an alloy or compound, or a material having one or more phases thereof at least in part, for example, is fired The negative electrode active material layer 2 and the negative electrode current collector 1 are preferably alloyed at least at a part of the interface. Specifically, the constituent elements of the negative electrode current collector 1 diffuse into the negative electrode active material layer 2 at the interface, the constituent elements of the negative electrode active material layer 2 diffuse into the negative electrode current collector 1, or those constituent elements It is preferred that they diffuse together. This is because breakage due to expansion and contraction of the negative electrode active material layer 2 due to charge / discharge is suppressed, and electronic conductivity between the negative electrode active material layer 2 and the negative electrode current collector 1 is improved.

  Examples of the conductive agent include carbon materials such as graphite, carbon black, acetylene black, and ketjen black. These may be used alone or in combination of two or more. Note that the conductive agent may be a metal material or a conductive polymer as long as it is a conductive material.

  As the binder, at least a polymer having a sulfonate ion group is used. The polymer having a sulfonic acid ion group is, for example, an alkali metal salt, and more specifically, lithium polyvinyl sulfonate having the structure shown in Chemical Formula 1 (1) and Chemical Polymer 1 (2). A lithium metal salt such as lithium polystyrene sulfonate having a structure, or a sodium metal salt such as sodium polyvinyl sulfonate or sodium polystyrene sulfonate. The polymer having a sulfonate ion group may further have a carboxylate ion group. That is, it may be a copolymer of a monomer having a sulfonate ion group and a monomer having a carboxylate ion group. Specifically, lithium metal salts such as poly (lithium styrenesulfonate-dilithium maleate) copolymer having the structure shown in (3) of Chemical Formula 1 and poly (sodium styrenesulfonate-disodium maleate) copolymer are used. Examples include sodium metal salts such as polymers. These may be used alone or in combination of two or more. Further, as the binder, a mixture of a polymer having a sulfonate ion group such as lithium polyvinyl sulfonate and a polymer having a carboxylic acid ion group such as dilithium maleate may be used. The negative electrode active material layer 2 may contain a decomposition product thereof together with the polymer having a sulfonate ion group as described above.

（ｋ，ｍおよびｎはそれぞれ２以上の整数を表す。）

(K, m, and n each represent an integer of 2 or more.)

  Such a binder has a function of improving the binding property of the negative electrode active material. For this reason, when this negative electrode is used in an electrochemical device such as a battery together with an electrolytic solution, the negative electrode active material may be pulverized or the negative electrode active material may fall off from the negative electrode current collector due to insertion and extraction of the electrode reactant. It is suppressed. The content of the binder in the negative electrode active material layer 2 is 1% by mass or more and 20% by mass or less in order to minimize the decrease in capacity and the increase in resistance while sufficiently exhibiting such effects. Is desirable.

  The negative electrode is manufactured, for example, by preparing the negative electrode current collector 1 and then forming the negative electrode active material layers 2 on both surfaces of the negative electrode current collector 1.

  When forming the negative electrode active material layer 2, for example, a negative electrode mixture in which a powder of a negative electrode active material, a conductive agent, and a polymer having a sulfonate ion group as a binder is mixed is dispersed in a solvent. Thus, a paste-like negative electrode mixture slurry is applied to the negative electrode current collector 1, dried (or baked), and then compression molded.

  According to the negative electrode and the method for producing the same, the negative electrode active material layer 2 includes a sulfonic acid ion together with a negative electrode active material containing at least one of a simple substance, an alloy and a compound of silicon, and a simple substance, an alloy and a compound of tin. Since a polymer having a group is included as a binder, the binding property of the negative electrode active material is increased as compared with the case where a salt (monomer) of polyacrylic acid or polymaleic acid is used as the binder. The conductivity between the electric body and the negative electrode active material is improved. As a result, when this negative electrode is used together with an electrolytic solution in an electrochemical device such as a battery, cycle characteristics can be improved.

  Next, usage examples of the above-described negative electrode will be described. Here, taking a battery as an example of an electrochemical device, the negative electrode is used in the battery as follows.

(First battery)
FIG. 2 shows a cross-sectional configuration of the first battery. This battery is, for example, a so-called lithium ion secondary battery in which the capacity of the negative electrode is represented by a capacity component based on insertion and extraction of lithium as an electrode reactant.

  The first battery includes a wound electrode body 20 in which a positive electrode 21 and a negative electrode 22 are wound through a separator 23 inside a substantially hollow cylindrical battery can 11, and a pair of insulating plates 12 and 13. It is stored. The battery can 11 is made of, for example, iron plated with nickel, and one end and the other end thereof are closed and opened, respectively. The pair of insulating plates 12 and 13 are arranged so as to extend perpendicular to the winding peripheral surface with the winding electrode body 20 interposed therebetween. The battery structure using the battery can 11 is called a so-called cylindrical type.

  A battery lid 14 and a safety valve mechanism 15 and a heat sensitive resistance element (Positive Temperature Coefficient; PTC element) 16 provided inside thereof are caulked through a gasket 17 at the open end of the battery can 11. The battery can 11 is hermetically sealed. The battery lid 14 is made of, for example, the same material as the battery can 11. The safety valve mechanism 15 is electrically connected to the battery lid 14 via the heat sensitive resistance element 16. In the safety valve mechanism 15, when the internal pressure becomes a certain level or more due to an internal short circuit or external heating, the electric power between the battery lid 14 and the wound electrode body 20 is reversed by reversing the disk plate 15 </ b> A. Connection is broken. The heat-sensitive resistor element 16 is configured to prevent abnormal heat generation caused by a large current by limiting the current by increasing the resistance in response to a rise in temperature. The gasket 17 is made of, for example, an insulating material, and asphalt is applied to the surface thereof.

  For example, a center pin 24 is inserted in the center of the wound electrode body 20. In this wound electrode body 20, a positive electrode lead 25 made of aluminum or the like is connected to the positive electrode 21, and a negative electrode lead 26 made of nickel or the like is connected to the negative electrode 22. The positive electrode lead 25 is electrically connected to the battery lid 14 by welding to the safety valve mechanism 15, and the negative electrode lead 26 is electrically connected to the battery can 11 by welding.

  FIG. 3 shows an enlarged part of the spirally wound electrode body 20 shown in FIG. The positive electrode 21 is, for example, one in which a positive electrode active material layer 21B is provided on both surfaces of a positive electrode current collector 21A. The positive electrode current collector 21A is made of, for example, a metal material such as aluminum, nickel, or stainless steel. The positive electrode active material layer 21B includes, for example, any one or more of positive electrode materials capable of inserting and extracting lithium as an electrode reactant as a positive electrode active material. An agent or a binder may be included. However, when the positive electrode 21 and the negative electrode 22 are wound as shown in FIG. 3 while including a binder, as the binder, a styrene butadiene rubber or a fluorine rubber having a high flexibility is used. Is preferably used.

As a positive electrode material capable of inserting and extracting lithium, for example, a lithium-containing compound is preferable. This is because a high energy density can be obtained. Examples of the lithium-containing compound include a composite oxide containing lithium and a transition metal element, or a phosphate compound containing lithium and a transition metal element. In particular, cobalt, nickel, manganese, and iron are used as the transition metal element. Those containing at least one of them are preferred. This is because a higher voltage can be obtained. The chemical formula is represented by, for example, Li _x M1O ₂ or Li _y M2PO ₄ . In the formula, M1 and M2 represent one or more transition metal elements. The values of x and y vary depending on the charge / discharge state of the battery, and are generally 0.05 ≦ x ≦ 1.10 and 0.05 ≦ y ≦ 1.10.

Examples of the lithium composite oxide containing lithium and a transition metal element include lithium cobalt composite oxide (Li _x CoO ₂ ), lithium nickel composite oxide (Li _x NiO ₂ ), and lithium nickel cobalt composite oxide (Li _{x (1-z)} Co _z O ₂ (z <1)), lithium nickel cobalt manganese composite oxide (Li _x Ni _(1-vw) Co _y Mn _w O ₂ (v + w <1)), or spinel type structure And a lithium manganese composite oxide (LiMn ₂ O ₄ ). Among these, a composite oxide containing nickel is preferable. This is because high capacity can be obtained and excellent cycle characteristics can be obtained. Examples of the phosphate compound containing lithium and a transition metal element include a lithium iron phosphate compound (LiFePO ₄ ) or a lithium iron manganese phosphate compound (LiFe _(1-u) Mn _u PO ₄ (u <1). ) And the like.

  In addition to the above, for example, oxides such as titanium oxide, vanadium oxide or manganese dioxide, disulfides such as iron disulfide, titanium disulfide or molybdenum sulfide, chalcogenides such as niobium selenide, sulfur, Examples thereof include conductive polymers such as polyaniline and polythiophene.

  The negative electrode 22 has, for example, the same configuration as that of the negative electrode shown in FIG. 1, and is provided with a negative electrode active material layer 22B on both surfaces of a strip-shaped negative electrode current collector 22A. The configurations of the negative electrode current collector 22A and the negative electrode active material layer 22B are the same as the configurations of the negative electrode current collector 1 and the negative electrode active material layer 2 described above, respectively. Note that the charge capacity of the negative electrode active material described above is larger than the charge capacity of the positive electrode active material by adjusting the amount between the negative electrode active material capable of inserting and extracting lithium and the positive electrode active material. It is comprised so that it may become.

  The separator 23 separates the positive electrode 21 and the negative electrode 22 and allows lithium ions to pass through while preventing a short circuit of current due to contact between the two electrodes. The separator 23 is made of, for example, a porous film made of synthetic resin made of polytetrafluoroethylene, polypropylene, polyethylene, or the like, or a porous film made of ceramic, and these two or more kinds of porous films are laminated. It may be made the structure. Among them, a porous film made of polyolefin is preferable because it is excellent in short-circuit preventing effect and can improve battery safety by a shutdown effect. In particular, polyethylene is preferable because a shutdown effect can be obtained within a range of 100 ° C. or more and 160 ° C. or less and the electrochemical stability is excellent. Polypropylene is also preferable, and other resins having chemical stability may be copolymerized with polyethylene or polypropylene, or may be blended.

  The separator 23 is impregnated with an electrolytic solution as a liquid electrolyte. This electrolytic solution contains a solvent and an electrolyte salt dissolved in the solvent.

  The solvent contains, for example, a nonaqueous solvent such as an organic solvent. Examples of the non-aqueous solvent include ethylene carbonate, propylene carbonate, butylene carbonate, dimethyl carbonate, diethyl carbonate, ethyl methyl carbonate, methyl propyl carbonate, γ-butyrolactone, γ-valerolactone, 1,2-dimethoxyethane, tetrahydrofuran, 2-methyltetrahydrofuran, tetrahydropyran, 1,3-dioxolane, 4-methyl-1,3-dioxolane, 1,3-dioxane, 1,4-dioxane, methyl acetate, ethyl acetate, methyl propionate, ethyl propionate, Methyl butyrate, methyl isobutyrate, methyl trimethylacetate, ethyl trimethylacetate, acetonitrile, glutaronitrile, adiponitrile, methoxyacetonitrile, 3-methoxypropionitrile, N, N-dimethylformamide, N-methylpyrrolidinone, N -Methyloxazolidinone, N, N'-dimethylimidazolidinone, nitromethane, nitroethane, sulfolane, trimethyl phosphate, dimethyl sulfoxide or dimethyl sulfoxide phosphoric acid. These may be used alone or in combination of two or more. Especially, it is preferable that the solvent contains at least one selected from the group consisting of ethylene carbonate, propylene carbonate, dimethyl carbonate, diethyl carbonate, and ethyl methyl carbonate. This is because sufficient cycle characteristics can be obtained. In this case, in particular, a high viscosity (high dielectric constant) solvent such as ethylene carbonate or propylene carbonate (for example, a relative dielectric constant ε ≧ 30) and a low viscosity solvent such as dimethyl carbonate, ethyl methyl carbonate or diethyl carbonate (for example, , Viscosity ≦ 1 mPa · s). This is because the dissociation property of the electrolyte salt and the ion mobility are improved, so that a higher effect can be obtained.

  This solvent preferably contains a cyclic carbonate having an unsaturated bond. This is because the cycle characteristics are improved. The content of the cyclic carbonate having an unsaturated bond in the solvent is preferably in the range of 0.01% by mass to 10.0% by mass. This is because a sufficient effect can be obtained. Examples of the cyclic carbonate having an unsaturated bond include vinylene carbonate and vinyl ethylene carbonate. These may be used alone or in combination of two or more.

  The solvent contains at least one member selected from the group consisting of a chain carbonate having a halogen represented by Chemical Formula 2 as a constituent element and a cyclic carbonate having a halogen represented by Chemical Formula 3 as a constituent element. It is preferable. This is because the cycle characteristics are further improved.

（Ｒ１１〜Ｒ１６は水素基、ハロゲン基、アルキル基あるいはハロゲン化アルキル基であり、それらは互いに同一でもよいし異なってもよいが、それらのうちの少なくとも１つはハロゲン基あるいはハロゲン化アルキル基である。ただし、ハロゲンはフッ素、塩素および臭素からなる群のうちの少なくとも１種である。）

(R11 to R16 are a hydrogen group, a halogen group, an alkyl group or a halogenated alkyl group, which may be the same or different from each other, but at least one of them is a halogen group or a halogenated alkyl group. Provided that the halogen is at least one member of the group consisting of fluorine, chlorine and bromine.)

（Ｒ２１〜Ｒ２４は水素基、ハロゲン基、アルキル基あるいはハロゲン化アルキル基であり、それらは互いに同一でもよいし異なってもよいが、それらのうちの少なくとも１つはハロゲン基あるいはハロゲン化アルキル基である。ただし、ハロゲンはフッ素、塩素および臭素からなる群のうちの少なくとも１種である。）

(R21 to R24 are a hydrogen group, a halogen group, an alkyl group or a halogenated alkyl group, and they may be the same or different, but at least one of them is a halogen group or a halogenated alkyl group. Provided that the halogen is at least one member of the group consisting of fluorine, chlorine and bromine.)

  Examples of the chain carbonate having a halogen shown in Chemical Formula 2 include fluoromethyl methyl carbonate, bis (fluoromethyl) carbonate, and difluoromethyl methyl carbonate. These may be used alone or in combination of two or more. Of these, bis (fluoromethyl) carbonate is preferred. This is because a sufficient effect can be obtained. In particular, a higher effect can be obtained by using together with the cyclic carbonate having halogen shown in Chemical formula 3.

  Examples of the cyclic ester carbonate having a halogen shown in Chemical formula 3 include a series of compounds represented by Chemical formula 4 and Chemical formula 5. That is, 4-fluoro-1,3-dioxolan-2-one of (1) shown in Chemical formula 4, 4-chloro-1,3-dioxolan-2-one of (2), 4,5 of (3) -Difluoro-1,3-dioxolan-2-one, (4) tetrafluoro-1,3-dioxolan-2-one, (5) 4-fluoro-5-chloro-1,3-dioxolane-2-one ON, (6) 4,5-dichloro-1,3-dioxolan-2-one, (7) tetrachloro-1,3-dioxolan-2-one, (8) 4,5-bistrifluoromethyl 1,3-dioxolan-2-one, 4-trifluoromethyl-1,3-dioxolan-2-one of (9), 4,5-difluoro-4,5-dimethyl-1,3 of (10) -Dioxolan-2-one, 4-methyl-5,5 of (11) Difluoro-1,3-dioxolan-2-one, and the like 5,5-difluoro-1,3-dioxolan-2-one (12). In addition, 4-trifluoromethyl-5-fluoro-1,3-dioxolan-2-one of (1) shown in Chemical Formula 5, 4-trifluoromethyl-5-methyl-1,3-dioxolane of (2) 2-one, 4-fluoro-4,5-dimethyl-1,3-dioxolan-2-one of (3), 4,4-difluoro-5- (1,1-difluoroethyl)-of (4) 1,3-dioxolan-2-one, 4,5-dichloro-4,5-dimethyl-1,3-dioxolan-2-one in (5), 4-ethyl-5-fluoro-1, in (6) 3-dioxolan-2-one, 4-ethyl-4,5-difluoro-1,3-dioxolan-2-one of (7), 4-ethyl-4,5,5-trifluoro-1 of (8) , 3-Dioxolan-2-one, 4-Fluoro-4-trifluoro of (9) Methyl-1,3-dioxolane-2-one. These may be used alone or in combination of two or more. Among these, at least one of 4-fluoro-1,3-dioxolan-2-one and 4,5-difluoro-1,3-dioxolan-2-one is preferable, and 4,5-difluoro-1,3- Dioxolan-2-one is more preferred. This is because they are easily available and higher effects can be obtained. In particular, as 4,5-difluoro-1,3-dioxolan-2-one, a trans isomer is preferable to a cis isomer in order to obtain a higher effect.

  Moreover, it is preferable that the solvent contains sultone (cyclic sulfonic acid ester) or an acid anhydride. This is because the cycle characteristics are further improved. Examples of sultone include propane sultone and propene sultone. These may be used alone or in combination of two or more. Of these, propene sultone is preferable. This is because a sufficient effect can be obtained. On the other hand, examples of the acid anhydride include carboxylic acid anhydrides such as succinic anhydride, disulfonic acid anhydrides such as ethanedisulfonic anhydride, and anhydrides of carboxylic acid and sulfonic acid such as anhydrous sulfobenzoic acid. Can be mentioned. These may be used alone or in combination of two or more. Of these, succinic anhydride or sulfobenzoic anhydride is preferable. This is because a sufficient effect can be obtained.

  The electrolyte salt contains, for example, one or more light metal salts such as a lithium salt. Examples of the lithium salt include at least one selected from the group consisting of lithium hexafluorophosphate, lithium tetrafluoroborate, lithium perchlorate, and lithium hexafluoroarsenate. This is because sufficient cycle characteristics can be obtained. These may be used alone or in combination of two or more. Among these, lithium hexafluorophosphate is preferable. This is because a higher effect can be obtained because the internal resistance is lowered.

  Moreover, it is preferable that electrolyte salt contains at least 1 sort (s) of the group which consists of a compound represented by Chemical formula 6, Chemical formula 7 and Chemical formula 8. This is because the cycle characteristics are further improved. These may be used alone or in combination of two or more. In particular, when the electrolyte salt contains the above-described lithium hexafluorophosphate and at least one selected from the group consisting of the compounds shown in Chemical Formulas 5 to 7, higher effects can be obtained.

（Ｘ３１は短周期型周期表における１Ａ族元素あるいは２Ａ族元素、またはアルミニウム（Ａｌ）である。Ｍ３１は遷移金属元素、または短周期型周期表における３Ｂ族元素、４Ｂ族元素あるいは５Ｂ族元素である。Ｒ３１はハロゲン基である。Ｙ３１は−ＯＣ−Ｒ３２−ＣＯ−、−ＯＣ−ＣＲ３３₂ −あるいは−ＯＣ−ＣＯ−である。ただし、Ｒ３２はアルキレン基、ハロゲン化アルキレン基、アリーレン基あるいはハロゲン化アリーレン基である。Ｒ３３はアルキル基、ハロゲン化アルキル基、アリール基あるいはハロゲン化アリール基であり、それは互いに同一でもよいし異なってもよい。なお、ａ３は１以上４以下の整数であり、ｂ３は０、２あるいは４であり、ｃ３、ｄ３、ｍ３およびｎ３は１以上３以下の整数である。）

(X31 is a 1A group element or 2A group element or aluminum (Al) in the short period type periodic table. M31 is a transition metal element, or a 3B group element, 4B group element or 5B group element in the short period type periodic table. R31 is a halogen group, and Y31 is —OC—R32—CO—, —OC—CR33 ₂ — or —OC—CO—, wherein R32 is an alkylene group, a halogenated alkylene group, an arylene group or a halogen. R33 is an alkyl group, a halogenated alkyl group, an aryl group or a halogenated aryl group, which may be the same or different from each other, wherein a3 is an integer of 1 or more and 4 or less, b3 is 0, 2 or 4, and c3, d3, m3 and n3 are integers of 1 or more and 3 or less.)

（Ｘ４１は短周期型周期表における１Ａ族元素あるいは２Ａ族元素である。Ｍ４１は遷移金属元素、または短周期型周期表における３Ｂ族元素、４Ｂ族元素あるいは５Ｂ族元素である。Ｙ４１は−ＯＣ−（ＣＲ４１₂ ）_b4−ＣＯ−、−Ｒ４３₂ Ｃ−（ＣＲ４２₂ ）_c4−ＣＯ−、−Ｒ４３₂ Ｃ−（ＣＲ４２₂ ）_c4−ＣＲ４３₂ −、−Ｒ４３₂ Ｃ−（ＣＲ４２₂ ）_c4−ＳＯ₂ −、−Ｏ₂ Ｓ−（ＣＲ４２₂ ）_d4−ＳＯ₂ −あるいは−ＯＣ−（ＣＲ４２₂ ）_d4−ＳＯ₂ −である。ただし、Ｒ４１およびＲ４３は水素基、アルキル基、ハロゲン基あるいはハロゲン化アルキル基であり、それぞれは互いに同一でもよいし異なってもよいが、それぞれのうちの少なくとも１つはハロゲン基あるいはハロゲン化アルキル基である。Ｒ４２は水素基、アルキル基、ハロゲン基あるいはハロゲン化アルキル基であり、それは互いに同一でもよいし異なってもよい。なお、ａ４、ｅ４およびｎ４は１あるいは２の整数であり、ｂ４およびｄ４は１以上４以下の整数であり、ｃ４は０以上４以下の整数であり、ｆ４およびｍ４は１以上３以下の整数である。）

(X41 is a group 1A element or a group 2A element in the short period type periodic table. M41 is a transition metal element, or a group 3B element, a group 4B element, or a group 5B element in the short period type periodic table. Y41 is —OC. _{- (CR41 2) b4 -CO -} , - R43 2 C- (CR42 2) c4 -CO -, - R43 2 C- (CR42 2) c4 -CR43 2 -, - R43 2 C- (CR42 2) c4 - SO ₂ —, —O ₂ S— (CR42 ₂ ) _d4 —SO ₂ — or —OC— (CR42 ₂ ) _d4 —SO ₂ —, wherein R41 and R43 are hydrogen, alkyl, halogen, or halogen Each of which may be the same as or different from each other, but at least one of them is a halogen group or a halogenated alkyl group, R42 is a hydrogen group, an alkyl group, A group, a halogen group or a halogenated alkyl group, which may be the same or different from each other, wherein a4, e4 and n4 are integers of 1 or 2, and b4 and d4 are integers of 1 or more and 4 or less. C4 is an integer of 0 or more and 4 or less, and f4 and m4 are integers of 1 or more and 3 or less.)

（Ｘ５１は短周期型周期表における１Ａ族元素あるいは２Ａ族元素である。Ｍ５１は遷移金属元素、または短周期型周期表における３Ｂ族元素、４Ｂ族元素あるいは５Ｂ族元素である。Ｒｆはフッ素化アルキル基あるいはフッ素化アリール基であり、いずれの炭素数も１〜１０である。Ｙ５１は−ＯＣ−（ＣＲ５１₂ ）_d5−ＣＯ−、−Ｒ５２₂ Ｃ−（ＣＲ５１₂ ）_d5−ＣＯ−、−Ｒ５２₂ Ｃ−（ＣＲ５１₂ ）_d5−ＣＲ５２₂ −、−Ｒ５２₂ Ｃ−（ＣＲ５１₂ ）_d5−ＳＯ₂ −、−Ｏ₂ Ｓ−（ＣＲ５１₂ ）_e5−ＳＯ₂ −あるいは−ＯＣ−（ＣＲ５１₂ ）_e5−ＳＯ₂ −である。ただし、Ｒ５１は水素基、アルキル基、ハロゲン基あるいはハロゲン化アルキル基であり、それは互いに同一でもよいし異なってもよい。Ｒ５２は水素基、アルキル基、ハロゲン基あるいはハロゲン化アルキル基であり、それは互いに同一でもよいし異なってもよいが、そのうちの少なくとも１つはハロゲン基あるいはハロゲン化アルキル基である。なお、ａ５、ｆ５およびｎ５は１あるいは２であり、ｂ５、ｃ５およびｅ５は１以上４以下の整数であり、ｄ５は０あるいは１以上４以下の整数であり、ｇ５およびｍ５は１以上３以下の整数である。）

(X51 is a group 1A element or a group 2A element in the short period type periodic table. M51 is a transition metal element, or a group 3B element, a group 4B element, or a group 5B element in the short period type periodic table. Rf is fluorinated. An alkyl group or a fluorinated aryl group, each having 1 to 10 carbon atoms Y51 is —OC— (CR51 ₂ ) _d5 —CO—, —R52 ₂ C— (CR51 ₂ ) _d5 —CO—, — _{R52 2 C- (CR51 2) d5} -CR52 2 -, - R52 2 C- (CR51 2) d5 -SO 2 -, - O 2 S- (CR51 2) e5 -SO 2 - or -OC- (CR51 ₂ ) _e5 -SO ₂ -. is, however, R51 is a hydrogen group, an alkyl group, a halogen group or a halogenated alkyl group, it is .R52 may differ and may be identical to one another hydrogen group, an alkyl group A halogen group or a halogenated alkyl group, which may be the same or different from each other, at least one of which is a halogen group or a halogenated alkyl group, wherein a5, f5 and n5 are 1 or 2; B5, c5 and e5 are integers of 1 or more and 4 or less, d5 is 0 or an integer of 1 or more and 4 or less, and g5 and m5 are integers of 1 or more and 3 or less.

  Examples of the compound shown in Chemical formula 6 include compounds represented by chemical formulas (1) to (6). Examples of the compound shown in Chemical formula 7 include the compounds shown in Chemical formulas (1) to (8). Examples of the compound shown in Chemical Formula 8 include the compound shown in Chemical Formula 10 (9). These may be used alone or in combination of two or more. Among these, as the compounds shown in Chemical formula 6 to Chemical formula 8, the compound shown in Chemical formula 9 (6) or Chemical formula 10 (2) is preferable. This is because a sufficient effect can be obtained. Needless to say, the compound having the structure shown in Chemical Formula 6 to Chemical Formula 8 is not limited to the compound shown in Chemical Formula 9 or Chemical Formula 10.

  Moreover, it is preferable that electrolyte salt contains at least 1 sort (s) of the group which consists of a compound represented by Chemical formula 11, Chemical formula 12, and Chemical formula 13. This is because the cycle characteristics are further improved. These may be used alone or in combination of two or more. In particular, when the electrolyte salt contains the above-described lithium hexafluorophosphate and at least one selected from the group consisting of the compounds shown in Chemical Formulas 11 to 13, higher effects can be obtained.

（ｍおよびｎは１以上の整数であり、それらは互いに同一でもよいし異なってもよい。）

(M and n are integers of 1 or more, and they may be the same or different.)

（Ｒ６１は炭素数２以上４以下の直鎖状あるいは分岐状のパーフルオロアルキレン基である。）

(R61 is a linear or branched perfluoroalkylene group having 2 to 4 carbon atoms.)

（ｐ、ｑおよびｒは１以上の整数であり、それらは互いに同一でもよいし異なってもよい。）

(P, q and r are integers of 1 or more, and they may be the same or different from each other.)

Examples of the chain compound shown in Chemical formula 11 include bis (trifluoromethanesulfonyl) imide lithium (LiN (CF ₃ SO ₂ ) ₂ ), bis (pentafluoroethanesulfonyl) imide lithium (LiN (C ₂ F ₅ SO ₂ ) ₂ ), (trifluoromethanesulfonyl) (pentafluoroethanesulfonyl) imide lithium (LiN (CF ₃ SO ₂ ) (C ₂ F ₅ SO ₂ )), (trifluoromethanesulfonyl) (heptafluoropropanesulfonyl) imide lithium ( LiN (CF ₃ SO ₂ ) (C ₃ F ₇ SO ₂ )) or (trifluoromethanesulfonyl) (nonafluorobutanesulfonyl) imidolithium (LiN (CF ₃ SO ₂ ) (C ₄ F ₉ SO ₂ )) It is done. These may be used alone or in combination of two or more.

  Examples of the cyclic compound represented by Chemical Formula 12 include a series of compounds represented by Chemical Formula 14 and the like. That is, 1,2-perfluoroethanedisulfonylimide lithium of (1) shown in Chemical formula 14, 1,3-perfluoropropane disulfonylimide lithium of (2), 1,3-perfluorobutane of (3) Disulfonylimide lithium, 1,4-perfluorobutane disulfonylimide lithium of (4), and the like. These may be used alone or in combination of two or more. Among these, 1,3-perfluoropropane disulfonylimide lithium is preferable. This is because a sufficient effect can be obtained.

Examples of the chain compound shown in Chemical formula 13 include lithium tris (trifluoromethanesulfonyl) methide (LiC (CF ₃ SO ₂ ) ₃ ).

  The content of the electrolyte salt is preferably in the range of 0.3 mol / kg or more and 3.0 mol / kg or less with respect to the solvent. Outside this range, the ionic conductivity is extremely lowered, so that there is a possibility that sufficient capacity characteristics and the like may not be obtained.

  This first battery can be manufactured, for example, as follows.

  First, the positive electrode 21 is manufactured by forming the positive electrode active material layer 21B on both surfaces of the positive electrode current collector 21A. In this case, a positive electrode mixture obtained by mixing a powder of the positive electrode active material, a conductive agent, and a binder is dispersed in a solvent to obtain a paste-like positive electrode mixture slurry. It is compression molded after being applied to the electric body 21A and dried. Further, for example, by forming the negative electrode active material layer 22B on both surfaces of the negative electrode current collector 22A by the same procedure as the above-described negative electrode manufacturing method, and forming the coating 22C on the negative electrode active material layer 22B, the negative electrode 22 is produced.

  Subsequently, the cathode lead 25 is attached by welding to the cathode current collector 21A, and the anode lead 26 is attached by welding to the anode current collector 22A. Subsequently, the wound electrode body 20 is formed by winding the positive electrode 21 and the negative electrode 22 through the separator 23, the front end portion of the positive electrode lead 25 is welded to the safety valve mechanism 15, and the front end portion of the negative electrode lead 26 is connected to the battery. After welding to the can 11, the wound electrode body 20 is housed inside the battery can 11 while being sandwiched between the pair of insulating plates 12 and 13. Subsequently, an electrolytic solution is injected into the battery can 11 and impregnated in the separator 23. Finally, the battery lid 14, the safety valve mechanism 15, and the heat sensitive resistance element 16 are fixed to the opening end of the battery can 11 by caulking through the gasket 17. Thereby, the secondary battery shown in FIGS. 2 and 3 is completed.

  In the first battery, when charged, for example, lithium ions are released from the positive electrode 21 into the electrolytic solution. At this time, while the coating 22C suppresses decomposition of the electrolytic solution, the released lithium ions efficiently pass through the coating 22C and are occluded in the negative electrode active material layer 22B. On the other hand, when discharging is performed, for example, lithium ions are released from the negative electrode active material layer 22B, and the lithium ions are occluded in the positive electrode 21 through the electrolytic solution.

  According to the first battery and the manufacturing method thereof, the negative electrode 22 has the same configuration as the negative electrode shown in FIG. 1 described above, and is manufactured by the same method as the negative electrode manufacturing method described above. Therefore, cycle characteristics can be improved.

  In particular, the solvent is at least one selected from the group consisting of a cyclic carbonate having an unsaturated bond, a chain carbonate having a halogen shown in Chemical Formula 1 and a cyclic carbonate having a halogen shown in Chemical Formula 2, If sultone or acid anhydride is contained, higher effects can be obtained.

  Further, if the electrolyte salt contains at least one of the group consisting of the compounds shown in Chemical Formula 5 to Chemical Formula 7 or at least one of the group consisting of the compounds shown in Chemical Formula 10 to Chemical Formula 12 Higher effects can be obtained.

(Second battery)
FIG. 4 illustrates an exploded perspective configuration of the second battery. In the second battery, a wound electrode body 30 to which a positive electrode lead 31 and a negative electrode lead 32 are attached is accommodated in a film-shaped exterior member 40. The battery structure using the film-shaped exterior member 40 is called a so-called laminate film type.

  For example, the positive electrode lead 31 and the negative electrode lead 32 are each led out in the same direction from the inside of the exterior member 40 toward the outside. The positive electrode lead 31 is made of, for example, a metal material such as aluminum. The negative electrode lead 32 is made of a metal material such as copper, nickel, or stainless steel, for example. Each metal material constituting the positive electrode lead 31 and the negative electrode lead 32 has a thin plate shape or a mesh shape.

  The exterior member 40 is made of, for example, a rectangular aluminum laminated film in which a nylon film, an aluminum foil, and a polyethylene film are bonded together in this order. In the exterior member 40, for example, a polyethylene film is opposed to the spirally wound electrode body 30, and each outer edge portion is in close contact with each other by fusion or an adhesive. An adhesive film 41 is inserted between the exterior member 40 and the positive electrode lead 31 and the negative electrode lead 32 to prevent intrusion of outside air. The adhesion film 41 is made of a material having adhesion to the positive electrode lead 31 and the negative electrode lead 32, for example, a polyolefin resin such as polyethylene, polypropylene, modified polyethylene, or modified polypropylene.

  The exterior member 40 may be constituted by a laminate film having another structure instead of the above-described three-layer aluminum laminate film, or may be constituted by a polymer film such as polypropylene or a metal film. May be.

  FIG. 5 illustrates a cross-sectional configuration along line VV of the spirally wound electrode body 30 illustrated in FIG. The electrode winding body 30 is obtained by winding a positive electrode 33 and a negative electrode 34 after being laminated via a separator 35 and an electrolyte 36, and an outermost peripheral portion thereof is protected by a protective tape 37.

  FIG. 6 shows an enlarged part of the spirally wound electrode body 30 shown in FIG. The positive electrode 33 is obtained by providing a positive electrode active material layer 33B on both surfaces of a positive electrode current collector 33A. The negative electrode 34 has, for example, the same configuration as that of the negative electrode shown in FIG. 1, and is provided with a negative electrode active material layer 34B on both surfaces of a negative electrode current collector 34A. The configurations of the positive electrode current collector 33A, the positive electrode active material layer 33B, the negative electrode current collector 34A, the negative electrode active material layer 34B, and the separator 35 are respectively the positive electrode current collector 21A, the positive electrode active material layer 21B in the first battery described above. The configurations of the negative electrode current collector 22A, the negative electrode active material layer 22B, and the separator 23 are the same.

  The electrolyte 36 includes an electrolytic solution and a polymer compound that holds the electrolytic solution, and is in a so-called gel form. The gel electrolyte is preferable because it can obtain high ionic conductivity (for example, 1 mS / cm or more at room temperature) and can prevent battery leakage.

  Examples of the polymer compound include, for example, an ether polymer compound such as polyethylene oxide or a crosslinked product containing polyethylene oxide, an ester polymer compound such as polymethacrylate or an acrylate polymer compound, polyvinylidene fluoride, or fluorine. And a vinylidene fluoride polymer such as a copolymer of vinylidene fluoride and hexafluoropropylene. These may be used alone, or a plurality of types may be mixed and used. In particular, from the viewpoint of redox stability, it is preferable to use a fluorine-based polymer compound such as a vinylidene fluoride polymer. The amount of the polymer compound added in the electrolytic solution varies depending on the compatibility between the two, but as an example, it is preferably in the range of 5% by mass to 50% by mass.

  The configuration of the electrolytic solution is the same as the configuration of the electrolytic solution in the first battery described above. However, the solvent in this case is not only a liquid solvent but also a broad concept including those having ion conductivity capable of dissociating the electrolyte salt. Accordingly, when a polymer compound having ion conductivity is used, the polymer compound is also included in the solvent.

  Instead of the electrolyte 36 in which the electrolytic solution is held by the polymer compound, the electrolytic solution may be used as it is. In this case, the separator 35 is impregnated with the electrolytic solution.

  This second battery can be manufactured, for example, by the following three types of manufacturing methods.

  In the first manufacturing method, first, the positive electrode 33 is formed by forming the positive electrode active material layers 33B on both surfaces of the positive electrode current collector 33A by the same procedure as in the first battery manufacturing method. For example, the negative electrode 34 is produced by forming the negative electrode active material layer 34B on both surfaces of the negative electrode current collector 34A by the same procedure as that of the negative electrode manufacturing method described above.

  Subsequently, a gel solution 36 is formed by preparing a precursor solution containing an electrolytic solution, a polymer compound, and a solvent, applying the precursor solution to the positive electrode 33 and the negative electrode 34, and volatilizing the solvent. Subsequently, the positive electrode lead 31 and the negative electrode lead 32 are attached to the positive electrode current collector 33A and the negative electrode current collector 34A, respectively. Subsequently, after the positive electrode 33 and the negative electrode 34 provided with the electrolyte 36 are laminated via the separator 35, the positive electrode 33 and the negative electrode 34 are wound in the longitudinal direction, and a protective tape 37 is adhered to the outermost peripheral portion thereof. Form. Subsequently, for example, the wound electrode body 30 is sandwiched between two film-shaped exterior members 40, and then the outer edge portions of the exterior member 40 are bonded to each other by thermal fusion or the like. Enclose. At that time, the adhesion film 41 is inserted between the positive electrode lead 31 and the negative electrode lead 32 and the exterior member 40. Thereby, the secondary battery shown in FIGS. 4 to 6 is completed.

  In the second manufacturing method, first, the positive electrode lead 31 and the negative electrode lead 32 are attached to the positive electrode 33 and the negative electrode 34, respectively, and then the positive electrode 33 and the negative electrode 34 are stacked and wound via the separator 35, and at the outermost peripheral portion. By adhering the protective tape 37, a wound body that is a precursor of the wound electrode body 30 is formed. Subsequently, after sandwiching the wound body between the two film-shaped exterior members 40, the remaining outer peripheral edge portion excluding the outer peripheral edge portion on one side is bonded by thermal fusion or the like, thereby forming a bag-like exterior. It is housed inside the member 40. Subsequently, an electrolyte composition containing an electrolytic solution, a monomer that is a raw material of the polymer compound, a polymerization initiator, and other materials such as a polymerization inhibitor as necessary is prepared, and a bag-shaped exterior member After injecting into the inside of 40, the opening part of the exterior member 40 is sealed by heat sealing or the like. Finally, the gel electrolyte 36 is formed by thermally polymerizing the monomer to obtain a polymer compound. Thereby, the secondary battery is completed.

  In the third manufacturing method, the wound body is formed to form the inside of the bag-shaped exterior member 40 in the same manner as in the first manufacturing method described above, except that the separator 35 coated with the polymer compound on both sides is used. Store in. Examples of the polymer compound applied to the separator 35 include a polymer containing vinylidene fluoride as a component, that is, a homopolymer, a copolymer, or a multi-component copolymer. Specifically, polyvinylidene fluoride, a binary copolymer containing vinylidene fluoride and hexafluoropropylene as components, and a ternary copolymer containing vinylidene fluoride, hexafluoropropylene and chlorotrifluoroethylene as components. Such as coalescence. In addition, the high molecular compound may contain the other 1 type, or 2 or more types of high molecular compound with the polymer which uses the above-mentioned vinylidene fluoride as a component. Subsequently, after the electrolytic solution is prepared and injected into the exterior member 40, the opening of the exterior member 40 is sealed by heat fusion or the like. Finally, the exterior member 40 is heated while applying a load, and the separator 35 is brought into close contact with the positive electrode 33 and the negative electrode 34 through the polymer compound. As a result, the electrolytic solution is impregnated into the polymer compound, and the polymer compound is gelled to form the electrolyte 36. Thus, the secondary battery is completed. In the third manufacturing method, the swollenness characteristics are improved as compared with the first manufacturing method. Further, in the third manufacturing method, compared with the second manufacturing method, there are hardly any monomers or solvents that are raw materials for the polymer compound remaining in the electrolyte 36, and the formation process of the polymer compound is well controlled. Therefore, sufficient adhesion is obtained between the positive electrode 33, the negative electrode 34, the separator 35, and the electrolyte 36.

  In this second battery, lithium ions are occluded and released between the positive electrode 33 and the negative electrode 34 as in the first battery described above. That is, when charged, for example, lithium ions are extracted from the positive electrode 33 and inserted in the negative electrode 34 through the electrolyte 36. On the other hand, when discharging is performed, lithium ions are released from the negative electrode 34 and inserted into the positive electrode 33 through the electrolyte 36.

  The operation and effect of the second battery and its manufacturing method are the same as those of the first battery described above.

(Third battery)
FIG. 7 illustrates an exploded perspective configuration of the third battery. In this third battery, the positive electrode 51 is attached to the outer can 54, the negative electrode 52 is accommodated in the outer cup 55, and they are laminated via the separator 53 impregnated with the electrolytic solution, and then caulked via the gasket 56. It is a thing. The battery structure using the outer can 54 and the outer cup 55 is called a so-called coin type.

  The positive electrode 51 is obtained by providing a positive electrode active material layer 51B on one surface of a positive electrode current collector 51A. The negative electrode 52 is obtained by providing a negative electrode active material layer 52B and a coating 52C on one surface of a positive electrode current collector 52A. The configurations of the positive electrode current collector 51A, the positive electrode active material layer 51B, the negative electrode current collector 52A, the negative electrode active material layer 52B, and the separator 53 are respectively the positive electrode current collector 21A, the positive electrode active material layer 21B in the first battery described above. The configurations of the negative electrode current collector 22A, the negative electrode active material layer 22B, and the separator 23 are the same.

  In this third battery, lithium ions are occluded and released between the positive electrode 51 and the negative electrode 52 as in the first battery described above. That is, when charged, for example, lithium ions are extracted from the positive electrode 51 and inserted in the negative electrode 52 through the electrolytic solution. On the other hand, when discharging is performed, lithium ions are released from the negative electrode 52 and inserted into the positive electrode 51 through the electrolytic solution.

  The operations and effects of the third battery and the manufacturing method thereof are the same as those of the first battery described above.

  Specific examples of the present invention will be described in detail.

(Example 1-1)
The coin-type secondary battery shown in FIG. 7 was fabricated using silicon as the negative electrode active material.

First, the positive electrode 51 was produced. Here, lithium carbonate (Li ₂ CO ₃ ) and cobalt carbonate (CoCO ₃ ) are mixed at a molar ratio of 0.5: 1, and then calcined in air at 900 ° C. for 5 hours, so that a lithium / cobalt composite is obtained. An oxide (LiCoO ₂ ) was obtained. Next, 94 parts by mass of lithium-cobalt composite oxide as a positive electrode active material, 3 parts by mass of graphite as a conductive agent, and 3 parts by mass of polyvinylidene fluoride as a binder were mixed to form a positive electrode mixture. -A paste-like positive electrode mixture slurry was prepared by dispersing in methyl-2-pyrrolidone. Subsequently, the positive electrode mixture slurry was applied to a positive electrode current collector 51A made of aluminum foil (20 μm thick) and dried, and then compression-molded with a roll press to form a positive electrode active material layer 51B. Finally, the positive electrode current collector 51A on which the positive electrode active material layer 51B was formed was punched out into a circular pellet having a diameter of 15 mm.

Subsequently, the negative electrode 52 was produced. Here, first, 90 parts by mass of silicon powder having an average particle diameter of 1 μm as a negative electrode active material and 10 parts by mass of lithium polyvinyl sulfonate as a binder are mixed to form a negative electrode mixture, which is then dispersed in water as a solvent. Thus, a paste-like negative electrode mixture slurry was obtained. After that, the negative electrode mixture slurry is uniformly applied to the negative electrode current collector 52A made of copper foil (18 μm thick), dried, pressurized, and heated in a vacuum atmosphere at 120 ° C. for 12 hours, thereby negative electrode active material Layer 52B was formed. After that, it was punched out into a round pellet having a diameter of 16 mm. Here, when the negative electrode active material layer 52B is analyzed by ToF-SIMS, a positive secondary ion peak C ₂ H ₃ SO ₃ Li ₂ derived from lithium vinyl sulfonate that is a repeating unit constituting lithium polyvinyl sulfonate is detected. It was. As a result, it was confirmed that the negative electrode active material layer 52B was configured to contain lithium polyvinyl sulfonate. In addition to the mass spectrometry as described above, polyvinyl sulfone can be obtained by detecting an IR spectrum from the negative electrode active material layer 52B or by analyzing the binder extracted from the negative electrode active material layer 52B with a solvent by NMR. It is also possible to confirm the presence of lithium acid.

  Subsequently, the positive electrode 51, the separator 53 made of a microporous polypropylene film (25 μm thick), and the negative electrode 52 are laminated so that the positive electrode active material layer 51B and the negative electrode active material layer 52B face each other with the separator 53 interposed therebetween. After that, it was housed in an outer can 54. After that, an electrolytic solution was injected and the outer cup 55 was covered and caulked through the gasket 56 to complete a coin-type secondary battery.

As an electrolytic solution, a mixed solvent in which ethylene carbonate (EC) and diethyl carbonate (DEC) were mixed as a solvent was used, and lithium hexafluorophosphate (LiPF ₆ ) was used as an electrolyte salt. At this time, the mixed solvent and the composition were EC: DEC = 30: 70 by mass ratio, and the concentration of lithium hexafluorophosphate in the electrolytic solution was 1 mol / kg.

(Example 1-2)
A secondary battery was made in the same manner as Example 1-1 except that 4-fluoro-1,3-dioxolan-2-one (FEC) was used instead of EC as the solvent. At this time, the composition of the mixed solvent was FEC: DEC = 30: 70 by mass ratio.

(Example 1-3)
A secondary battery was fabricated in the same manner as in Example 1-1 except that 4,5-difluoro-1,3-dioxolan-2-one (DFEC) was added as a solvent and the composition of the mixed solvent was changed. did. At this time, the composition of the mixed solvent was EC: DFEC: DEC = 20: 10: 70 by mass ratio.

(Example 1-4)
A secondary battery was fabricated in the same manner as in Example 1-1 except that vinylene carbonate (VC) was added as a solvent and the composition of the mixed solvent was changed. At this time, the composition of the mixed solvent was EC: DEC: VC = 29: 70: 1 by mass ratio.

(Example 1-5)
The same procedure as in Example 2-2 was performed except that bis (fluoromethyl) carbonate (DFDMC) was added as a solvent and the composition of the mixed solvent was changed. At this time, the composition of the mixed solvent was FEC: DEC: DFDMC = 30: 70: 5 by mass ratio.

(Example 1-6)
A secondary battery was fabricated in the same manner as in Example 1-1, except that the negative electrode active material layer 52B was formed using lithium polystyrene sulfonate instead of lithium polyvinyl sulfonate as the binder.

(Example 1-7)
A secondary battery was fabricated in the same manner as in Example 1-2 except that the negative electrode active material layer 52B was formed using lithium polystyrene sulfonate instead of lithium polyvinyl sulfonate as the binder.

(Example 1-8)
A secondary battery was fabricated in the same manner as in Example 1-3 except that the negative electrode active material layer 52B was formed using lithium polystyrene sulfonate instead of lithium polyvinyl sulfonate as the binder.

(Example 1-9)
A secondary battery was fabricated in the same manner as in Example 1-4, except that the negative electrode active material layer 52B was formed using lithium polystyrene sulfonate instead of lithium polyvinyl sulfonate as the binder.

(Example 1-10)
The same procedure as in Example 1-1 was performed except that the negative electrode active material layer 52B was formed using a poly (lithium styrenesulfonate-dilithium maleate) copolymer instead of lithium polyvinylsulfonate as a binder. A secondary battery was produced.

(Example 1-11)
The same procedure as in Example 1-2 was performed except that the negative electrode active material layer 52B was formed using a poly (lithium styrenesulfonate-dilithium maleate) copolymer instead of lithium polyvinylsulfonate as a binder. A secondary battery was produced.

(Example 1-12)
The same procedure as in Example 1-3 was performed except that the negative electrode active material layer 52B was formed using a poly (lithium styrenesulfonate-dilithium maleate) copolymer instead of lithium polyvinylsulfonate as a binder. A secondary battery was produced.

(Example 1-13)
The same procedure as in Example 1-4 was performed except that the negative electrode active material layer 52B was formed using a poly (lithium styrenesulfonate-dilithium maleate) copolymer instead of lithium polyvinylsulfonate as a binder. A secondary battery was produced.

(Comparative Example 1-1)
A secondary battery was fabricated in the same manner as in Example 1-1 except that the negative electrode active material layer 52B was formed using polyvinylidene fluoride instead of lithium polyvinyl sulfonate as a binder.

(Comparative Example 1-2)
A secondary battery was fabricated in the same manner as in Example 1-1, except that the negative electrode active material layer 52B was formed using lithium polyacrylate instead of lithium polyvinyl sulfonate as the binder.

(Comparative Example 1-3)
A secondary battery was fabricated in the same manner as in Example 1-1 except that the negative electrode active material layer 52B was formed using dilithium polymaleate instead of lithium polyvinyl sulfonate as a binder.

(Comparative Example 1-4)
A secondary battery was fabricated in the same manner as in Example 1-1, except that the negative electrode active material layer 52B was formed using polysulfone instead of lithium polyvinyl sulfonate as a binder.

  When the cycle test was performed on the secondary batteries of Examples 1-1 to 1-13 and Comparative Examples 1-1 to 1-4 and the discharge capacity retention ratio was examined, the results shown in Table 1 were obtained. .

In the cycle test, each secondary battery was repeatedly charged and discharged according to the following procedure to obtain the discharge capacity maintenance rate. First, the discharge capacity at the second cycle was measured by charging and discharging two cycles in an atmosphere at 23 ° C. Subsequently, the discharge capacity at the 100th cycle was measured by charging and discharging in the same atmosphere until the total number of cycles reached 100 cycles. Finally, discharge capacity retention ratio (%) = (discharge capacity at the 100th cycle / discharge capacity at the second cycle) × 100 was calculated. As a charge / discharge condition for one cycle, the battery was charged at a constant current of 0.2 C until the battery voltage reached 4.2 V, and further charged at a constant voltage of 4.2 V until the current density reached 0.02 mA / cm ² . After that, the battery was discharged at a constant current of 0.2 C until the battery voltage reached 2.5V. Note that 0.2 C is a current value at which the theoretical capacity can be discharged (or charged) in 5 hours.

  The cycle test procedure and conditions described above are the same for the series of examples and comparative examples described below.

As shown in Table 1, in Examples 1-1 to 1-13 using a polymer having a sulfonate ion group such as lithium polyvinyl sulfonate as a binder, Comparative Example 1-1 in which it was not used A discharge capacity retention rate higher than ˜1-4 was obtained. Moreover, by comparison with Examples 1-1 to 1-4 and Examples 1-6 to 1-8, it is higher when lithium polyvinyl sulfonate is used than when lithium polystyrene sulfonate is used as the binder. It was found that a discharge capacity retention rate was obtained. Further, by comparing Examples 1-1 to 1-4 with Examples 1-10 to 1-13, the carboxylic acid was more carboxylic than when a sulfonate polymer (that is, lithium polyvinyl sulfonate) was used as the binder. It has been found that a higher discharge capacity retention ratio can be obtained when using a copolymer of an acid salt and a sulfonate (that is, a poly (lithium styrenesulfonate-dilithium maleate) copolymer). In addition, when lithium polyvinyl sulfonate is used as the binder, the discharge capacity in Examples 1-2 to 1-5 to which FEC, DFEC, VC, or DFDMC was added was higher than that in Example 1-1 to which they were not added. The maintenance rate showed a tendency to increase. When using polystyrene sulfonate lithium (Examples 1-6 to 1-9) and using a poly (lithium styrenesulfonate-dilithium maleate) copolymer (Examples 1-10 to 1-13) ) Showed the same tendency. Thus, it was confirmed that it is particularly advantageous for improving the cycle characteristics that the electrolytic solution contains a cyclic carbonate having halogen or a chain carbonate having halogen as a solvent. In addition, when the discharge capacity maintenance rate was investigated about the secondary battery which has the structure similar to a present Example (Examples 1-1 to 1-11) except having used sodium salt as electrolyte salt, as electrolyte salt, more of this embodiment using a lithium salt (LiPF ₆₎ showed a high discharge capacity retention ratio. This confirms that higher cycle characteristics can be obtained when the electrode reactant is lithium ion.

(Example 2-1)
A secondary battery was fabricated in the same manner as in Example 1-1, except that the negative electrode active material layer 52B was formed using sodium polyvinyl sulfonate instead of lithium polyvinyl sulfonate as a binder.

(Example 2-2)
A secondary battery was fabricated in the same manner as in Example 1-6, except that the negative electrode active material layer 52B was formed using sodium polystyrene sulfonate instead of lithium polystyrene sulfonate as the binder.

(Example 2-3)
Except that the negative electrode active material layer 52B was formed using a poly (sodium styrenesulfonate-disodium maleate) copolymer instead of a poly (lithium styrenesulfonate-dilithium maleate) copolymer as a binder. A secondary battery was made in the same manner as Example 1-10.

  When the cycle test was done about the secondary battery of these Examples 2-1 to 2-3 and the discharge capacity maintenance factor was investigated, the result shown in Table 2 was obtained. Table 2 also shows data relating to Examples 1-1, 1-6, 1-10 and Comparative Examples 1-1 to 1-4.

  As shown in Table 2, when a sodium salt is used instead of a lithium salt as a polymer having a sulfonic acid ion group, a higher discharge capacity retention rate than Comparative Examples 1-1 to 1-4 is obtained. It was.

(Examples 3-1 to 3-3)
As a solvent, propene sultone (PRS: Example 3-1) as a sultone, succinic anhydride (SCAH: Example 3-2) as an acid anhydride, or anhydrous sulfobenzoic acid (SBAH: as an acid anhydride) A secondary battery was made in the same manner as Example 1-2 except that Example 3-3) was added. At this time, the amount added was 1% by mass with respect to 100% by mass of the solvent of the electrolytic solution.

  When the cycle test was done about the secondary battery of these Examples 3-1 to 3-3 and the discharge capacity maintenance factor was investigated, the result shown in Table 3 was obtained. Table 3 also shows data related to Example 1-2.

  As shown in Table 3, in Examples 3-1 to 3-3 to which PRS, SCAH, or SBAH was added as a solvent, a discharge capacity maintenance rate equal to or higher than that of Example 1-2 in which they were not added was obtained. It was.

(Examples 4-1 to 4-4)
As an electrolyte salt, lithium tetrafluoroborate (LiBF ₄ : Example 4-1), a compound shown in Chemical Formula 8 (6) (Example 4-2), a compound shown in Chemical Formula 9 (2) (Example 4) -3) or a secondary battery was fabricated in the same manner as in Example 2-2 except that the compound shown in Chemical formula 14 (2) (Example 4-4) was added. At this time, the concentration of lithium hexafluorophosphate in the electrolyte was 0.9 mol / kg, and the concentration of the added compound was 0.1 mol / kg.

  When the cycle test was done about the secondary battery of these Examples 4-1 to 4-4 and the discharge capacity maintenance factor was investigated, the result shown in Table 4 was obtained. Table 4 also shows data related to Example 1-2.

  As shown in Table 4, in Examples 4-1 to 4-4 in which a predetermined compound or the like was added as an electrolyte salt together with lithium hexafluorophosphate, the discharge capacity was maintained equal to or higher than that of Example 1-2. The rate was obtained. Thus, even when the electrolytic solution contains lithium tetrafluoroborate, a compound shown in Chemical formula 6, a compound shown in Chemical formula 7 or a compound shown in Chemical formula 12 as an electrolyte salt, good cycle characteristics are obtained. It was confirmed that

  Here, in the case where the electrolytic solution contains lithium perchlorate, lithium hexafluoroarsenate, the compound shown in Chemical formula 8, the compound shown in Chemical formula 11 or the compound shown in Chemical formula 13 as the electrolyte salt, the discharge capacity is maintained. Although the rate is not shown, when the discharge capacity retention rate was examined in that case as well, a tendency to improve the cycle characteristics was confirmed.

(Example 5-1)
A secondary battery was fabricated in the same manner as in Example 1-1 except that tin-cobalt alloy (SnCo) was used as the negative electrode active material. Here, the negative electrode 52 was produced as follows. First, tin / cobalt / indium / titanium alloy powder was prepared, and this and carbon powder were dry-mixed, and then a CoSnC-containing material was produced by utilizing a mechanochemical reaction. When the composition of this CoSnC-containing material was analyzed, the mass ratio was Sn: Co: C = 48: 23: 20, and the ratio of cobalt to the total of tin and cobalt (Co / (Sn + Co) ratio) was 32 mass%. Met. Subsequently, 80% by mass of the above CoSnC-containing material, 10% by mass of graphite as a conductive agent, and 10% by mass of lithium polyvinyl sulfonate as a binder were mixed to form a negative electrode mixture, and then added to water as a solvent. By making it disperse | distribute, it was set as the paste-form negative mix slurry. After that, the negative electrode mixture slurry was uniformly applied to the negative electrode current collector 52A made of copper foil (18 μm thick), dried and then pressed to form the negative electrode active material layer 52B. After that, it was punched out into a round pellet having a diameter of 16 mm.

(Example 5-2)
A secondary battery was fabricated in the same manner as in Example 5-1, except that the negative electrode active material layer 52B was formed using lithium polystyrene sulfonate instead of lithium polyvinyl sulfonate as the binder.

(Example 5-3)
The same procedure as in Example 5-1 was conducted except that the negative electrode active material layer 52B was formed using a poly (lithium styrenesulfonate-dilithium maleate) copolymer instead of lithium polyvinylsulfonate as a binder. A secondary battery was produced.

(Example 5-4)
A secondary battery was fabricated in the same manner as in Example 5-1, except that the negative electrode active material layer 52B was formed using sodium polyvinyl sulfonate instead of lithium polyvinyl sulfonate as the binder.

(Example 5-5)
A secondary battery was fabricated in the same manner as in Example 5-2, except that the negative electrode active material layer 52B was formed using sodium polystyrene sulfonate instead of lithium polystyrene sulfonate as the binder.

(Example 5-6)
Except that the negative electrode active material layer 52B was formed using a poly (sodium styrenesulfonate-disodium maleate) copolymer instead of a poly (lithium styrenesulfonate-dilithium maleate) copolymer as a binder. A secondary battery was made in the same manner as Example 5-3.

(Comparative Example 5-1)
A secondary battery was fabricated in the same manner as in Example 5-1, except that the negative electrode 52 was fabricated without using a polymer having a sulfonate ion group as a binder in the negative electrode active material layer 52B. Here, the negative electrode 52 was produced as follows. First, tin / cobalt / indium / titanium alloy powder was prepared, and this and carbon powder were dry-mixed, and then a CoSnC-containing material was produced by utilizing a mechanochemical reaction. Subsequently, 80% by mass of the CoSnC-containing material, 10% by mass of graphite as a conductive agent, 8% by mass of polyvinylidene fluoride (melting point 170 ° C.) as a binder, and 2% by mass of sodium salt of carboxymethyl cellulose as a thickener. % Was mixed to make a negative electrode mixture, and then dispersed in water as a solvent to obtain a paste-like negative electrode mixture slurry. After that, the negative electrode mixture slurry was uniformly applied to the negative electrode current collector 52A made of copper foil (18 μm thick), dried and then pressed to form the negative electrode active material layer 52B. After that, it was punched out into a round pellet having a diameter of 16 mm.

(Comparative Example 5-2)
A secondary battery was fabricated in the same manner as in Comparative Example 5-1, except that the negative electrode active material layer 52B was formed using lithium polyacrylate instead of polyvinylidene fluoride as the binder.

(Comparative Example 5-3)
A secondary battery was fabricated in the same manner as in Comparative Example 5-1, except that the negative electrode active material layer 52B was formed using dilithium polymaleate instead of polyvinylidene fluoride as a binder.

(Comparative Example 5-4)
A secondary battery was fabricated in the same manner as in Comparative Example 5-1, except that the negative electrode active material layer 52B was formed using polysulfone instead of polyvinylidene fluoride as the binder.

  When the cycle tests were conducted on the secondary batteries of Examples 5-1 to 5-6 and Comparative Examples 5-1 to 5-4 and the discharge capacity retention ratio was examined, the results shown in Table 5 were obtained. .

  As shown in Table 5, when SnCo alloy was used as the negative electrode active material, the same tendency as when silicon was used as the negative electrode active material was confirmed. Specifically, in Examples 5-1 to 5-6 using a polymer having a sulfonate ion group as a binder, the discharge capacity was higher than those of Comparative Examples 5-1 to 5-4 without using the polymer. A retention rate was obtained. In addition, a higher discharge capacity retention rate was obtained when lithium polyvinyl sulfonate was used than when lithium polystyrene sulfonate was used as the binder. Furthermore, it was found that a higher discharge capacity retention rate was obtained when a copolymer of carboxylate and sulfonate was used than when a sulfonate polymer was used as the binder. Although not shown here, even when an SnCo alloy is used as the negative electrode active material, the electrolytic solution contains a cyclic carbonate having halogen or a chain carbonate having halogen as a solvent. It was confirmed to be particularly advantageous for improvement.

  In each of the above examples, the coin-type secondary battery has been described. However, the same tendency as the coin-type secondary battery was confirmed for the cylindrical and laminated film-type secondary batteries. In other words, cycle characteristics are improved by including a polymer having a sulfonic acid ion group as a binder, regardless of the method for forming the negative electrode active material layer, the type of negative electrode active material, the battery structure, and the like. It was confirmed that it can be made.

  The present invention has been described with reference to the embodiments and examples. However, the present invention is not limited to the embodiments described in the above embodiments and examples, and various modifications can be made. For example, the use application of the negative electrode of the present invention is not necessarily limited to a battery, but may be an electrochemical device other than a battery. Other applications include, for example, capacitors.

  In the above-described embodiments and examples, the polymer having a sulfonate ion group is used as a binder in the negative electrode active material layer, but it is used as a binder in the positive electrode active material layer. It may be.

  In the above-described embodiments and examples, the case where the electrolyte solution or the gel electrolyte in which the electrolyte solution is held in a polymer compound is used as the electrolyte of the battery of the present invention has been described. May be used. Other electrolytes include, for example, a mixture of an ion conductive inorganic compound such as ion conductive ceramics, ion conductive glass or ionic crystal and an electrolyte, or a mixture of another inorganic compound and an electrolyte. Or a mixture of these inorganic compounds and a gel electrolyte.

  In the above-described embodiments and examples, as the battery of the present invention, a lithium ion secondary battery in which the capacity of the negative electrode is expressed based on insertion and extraction of lithium is used, and the capacity of the negative electrode is precipitation and dissolution of lithium. Although the lithium metal secondary battery represented by the capacity based on the above has been described, the present invention is not necessarily limited thereto. In the battery of the present invention, the negative electrode material capable of occluding and releasing lithium has a smaller charge capacity than that of the positive electrode, so that the negative electrode capacity is based on the storage and release of lithium and the deposition of lithium and The present invention can be similarly applied to a secondary battery including a capacity based on melting and represented by the sum of the capacities.

  In the above-described embodiments and examples, the case where lithium is used as the electrode reactant is mainly described. However, the group 1A elements in other short-period periodic tables such as sodium (Na) or potassium (K) , 2A group elements such as magnesium or calcium (Ca), and other light metals such as aluminum may be used. Also in this case, the negative electrode material described in the above embodiment can be used as the negative electrode active material.

  Further, in the above-described embodiments or examples, the battery of the present invention is described by taking the case where the battery structure is a cylindrical type, the laminate film type and the coin type, and the case where the battery element has a winding structure as an example. However, the battery of the present invention can be similarly applied to the case where the battery element has another battery structure such as a square shape or the case where the battery element has another structure such as a laminated structure.

It is sectional drawing showing the structure of the negative electrode which concerns on one embodiment of this invention. It is sectional drawing showing the structure of the 1st battery using the negative electrode which concerns on one embodiment of this invention. It is sectional drawing which expands and represents a part of winding electrode body shown in FIG. It is a disassembled perspective view showing the structure of the 2nd battery using the negative electrode which concerns on one embodiment of this invention. It is sectional drawing showing the structure along the VV line of the winding electrode body shown in FIG. It is sectional drawing which expands and represents a part of winding electrode body shown in FIG. It is sectional drawing showing the structure of the 3rd battery using the negative electrode which concerns on one embodiment of this invention.

Explanation of symbols

  1, 22A, 34A, 52A ... negative electrode current collector, 2, 22B, 34B, 52B ... negative electrode active material layer, 2A ... negative electrode active material particles, 11 ... battery can, 12, 13 ... insulating plate, 14 ... battery lid, DESCRIPTION OF SYMBOLS 15 ... Safety valve mechanism, 15A ... Disc board, 16 ... Heat sensitive resistance element, 17, 56 ... Gasket, 20, 30 ... Winding electrode body, 21, 33, 51 ... Positive electrode, 21A, 33A, 51A ... Positive electrode collector 21B, 33B, 51B ... positive electrode active material layer, 22, 34, 52 ... negative electrode, 23, 35, 53 ... separator, 24 ... center pin, 25, 31 ... positive electrode lead, 26, 32 ... negative electrode lead, 36 ... electrolyte 37 ... protective tape, 40 ... exterior member, 41 ... adhesion film, 54 ... exterior can, 55 ... exterior cup.

Claims (12)

Negative electrode active material containing at least one of a simple substance, an alloy and a compound of silicon, and a simple substance, an alloy and a compound of tin, and a poly (lithium styrenesulfonate-dilithium maleate) copolymer or poly (styrenesulfonate) And a negative electrode active material layer including a sodium-disodium maleate copolymer).
Negative electrode for lithium ion secondary battery . The negative electrode active material layer includes a poly (lithium styrenesulfonate-dilithium maleate) copolymer or a poly (sodium styrenesulfonate-disodium maleate) copolymer as a binder,
The content of the binder in the negative electrode active material layer is 1% by mass or more and 20% by mass or less.
The negative electrode for a lithium ion secondary battery according to claim 1. A lithium ion secondary battery including an electrolyte solution together with a positive electrode and a negative electrode,
The negative electrode is
Negative electrode active material containing at least one of a simple substance, an alloy and a compound of silicon, and a simple substance, an alloy and a compound of tin, and a poly (lithium styrenesulfonate-dilithium maleate) copolymer or poly (styrenesulfonate) And a negative electrode active material layer including a sodium-disodium maleate copolymer).
Lithium ion secondary battery. The negative electrode active material layer includes a poly (lithium styrenesulfonate-dilithium maleate) copolymer or a poly (sodium styrenesulfonate-disodium maleate) copolymer as a binder,
The content of the binder in the negative electrode active material layer is 1% by mass or more and 20% by mass or less.
The lithium ion secondary battery according to claim 3. The electrolytic solution includes a solvent containing a cyclic carbonate having an unsaturated bond.
The lithium ion secondary battery according to claim 3 . The electrolytic solution includes a solvent containing at least one selected from the group consisting of a chain carbonate having a halogen represented by Chemical Formula 1 and a cyclic carbonate having a halogen represented by Chemical Formula 2.
The lithium ion secondary battery according to claim 3 .

(R11 to R16 are a hydrogen group, a halogen group, an alkyl group or a halogenated alkyl group, and at least one of them is a halogen group or a halogenated alkyl group.)

(R21 to R24 are a hydrogen group, a halogen group, an alkyl group or a halogenated alkyl group, and at least one of them is a halogen group or a halogenated alkyl group.) The chain ester carbonate having halogen is at least one selected from the group consisting of fluoromethyl methyl carbonate, bis (fluoromethyl) carbonate and difluoromethyl methyl carbonate,
The cyclic ester carbonate having a halogen is at least one of 4-fluoro-1,3-dioxolan-2-one and 4,5-difluoro-1,3-dioxolan-2-one.
The lithium ion secondary battery according to claim 6 . The electrolytic solution includes a solvent containing sultone.
The lithium ion secondary battery according to claim 3 . The electrolytic solution includes a solvent containing an acid anhydride.
The lithium ion secondary battery according to claim 3 . The electrolytic solution includes an electrolyte salt containing at least one member selected from the group consisting of compounds represented by chemical formulas 3, 4 and 5.
The lithium ion secondary battery according to claim 3 .

(X31 is a 1A group element or 2A group element or aluminum in the short period type periodic table. M31 is a transition metal element, or a 3B group element, 4B group element or 5B group element in the short period type periodic table. R31 Y 31 is —OC—R 32 —CO—, —OC—CR 33 ₂ — or —OC—CO—, wherein R 32 is an alkylene group, a halogenated alkylene group, an arylene group or a halogenated arylene group. R33 is an alkyl group, a halogenated alkyl group, an aryl group or a halogenated aryl group, wherein a3 is an integer of 1 or more and 4 or less, b3 is 0, 2 or 4, c3, d3, m3 and n3 are integers of 1 or more and 3 or less.)

(X41 is a group 1A element or a group 2A element in the short period type periodic table. M41 is a transition metal element, or a group 3B element, a group 4B element, or a group 5B element in the short period type periodic table. Y41 is —OC. _{- (CR41 2) b4 -CO -} , - R43 2 C- (CR42 2) c4 -CO -, - R43 2 C- (CR42 2) c4 -CR43 2 -, - R43 2 C- (CR42 2) c4 - SO ₂ —, —O ₂ S— (CR42 ₂ ) _d4 —SO ₂ — or —OC— (CR42 ₂ ) _d4 —SO ₂ —, wherein R41 and R43 are hydrogen, alkyl, halogen, or halogen And at least one of them is a halogen group or a halogenated alkyl group, and R42 is a hydrogen group, an alkyl group, a halogen group or a halogenated alkyl group. A4, e4 and n4 are 1 or 2, b4 and d4 are integers of 1 or more and 4 or less, c4 is an integer of 0 or more and 4 or less, and f4 and m4 are integers of 1 or more and 3 or less. .)

(X51 is a group 1A element or a group 2A element in the short period type periodic table. M51 is a transition metal element, or a group 3B element, a group 4B element, or a group 5B element in the short period type periodic table. Rf is fluorinated. an alkyl group or a fluorinated aryl group, any number of carbon atoms is also 1 to 10 .Y51 is _{-OC- (CR51 2) d5 -CO -} , - R52 2 C- (CR51 2) d5 -CO-, _{-R52 2 C- (CR51 2) d5} -CR52 2 -, - R52 2 C- (CR51 2) d5 -SO 2 -, - O 2 S- (CR51 2) e5 -SO 2 - or -OC- (CR51 _{2) e5} -SO ₂ -. is, however, R51 is a hydrogen group, an alkyl group, a halogen group or a halogenated alkyl group .R52 hydrogen group, an alkyl group, a halogen group or a halogenated alkyl At least one of which is a halogen group or a halogenated alkyl group, wherein a5, f5 and n5 are 1 or 2, b5, c5 and e5 are integers of 1 or more and 4 or less, d5 Is an integer from 0 to 4, and g5 and m5 are integers from 1 to 3. The compound represented by Chemical Formula 3 is at least one selected from the group consisting of the compounds represented by Chemical Formulas (1) to (6). The compound represented by Chemical Formula 4 is represented by Chemical Formula (1) ) To (8) is at least one member selected from the group consisting of the compounds represented by the formula (5), and the compound represented by the chemical formula 5 is a compound represented by the chemical formula (9).
The lithium ion secondary battery according to claim 10 .

The electrolyte includes lithium hexafluorophosphate (LiPF ₆ ), lithium tetrafluoroborate (LiBF ₄ ), lithium perchlorate (LiClO ₄ ), lithium hexafluoroarsenate (LiAsF ₆ ), and chemical formula 8 And an electrolyte salt containing at least one member selected from the group consisting of compounds represented by Chemical formula 9 and Chemical formula 10
The lithium ion secondary battery according to claim 3 .

(M and n are integers of 1 or more.)

(R61 is a linear or branched perfluoroalkylene group having 2 to 4 carbon atoms.)

(P, q and r are integers of 1 or more.)

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