JP2016119449A - Nonaqueous electrolyte storage element - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a nonaqueous electrolyte storage element, which can realize a high energy density and a high load discharge performance, and has improved charge-discharge cycle characteristics.SOLUTION: A nonaqueous electrolyte storage element includes: a positive electrode including a positive electrode material layer which contains a positive electrode active material capable of reversibly accumulating and releasing anions; a negative electrode including a negative electrode material layer which contains a negative electrode active material capable of reversibly accumulating and releasing cations; a separator disposed between the positive electrode and the negative electrode; and a nonaqueous electrolyte containing an electrolyte salt. The nonaqueous electrolyte storage element satisfies the following formula: 0.5≤[(V1+V2+V3)/V4]≤0.61, where V1 is the volume of pores of the positive electrode material layer per unit area of the positive electrode, V2 is the volume of pores of the negative electrode material layer per unit area of the negative electrode, V3 is the volume of pores per unit area of the separator, and V4 is the total volume of the nonaqueous electrolyte storage element. The nonaqueous electrolyte storage element also satisfies the following formula: 0.14≤P1/P2≤0.84, where P1 is the porosity of the positive electrode material layer, and P2 is the porosity of the separator.SELECTED DRAWING: Figure 1

Description

  The present invention relates to a non-aqueous electrolyte storage element.

  In recent years, with the miniaturization and high performance of portable devices, the characteristics of non-aqueous electrolyte storage elements having a high energy density have been improved and become widespread. In addition, attempts have been made to improve the high-load discharge performance of non-aqueous electrolyte storage elements and to improve the weight energy density with the aim of developing applications in electric vehicles.

Conventionally, as a non-aqueous electrolyte storage element, a lithium ion non-aqueous electrolysis having a positive electrode such as a lithium cobalt composite oxide, a carbon negative electrode, and a non-aqueous electrolyte obtained by dissolving a lithium salt in a non-aqueous solvent. Many liquid storage elements are used.
On the other hand, using a material such as a conductive polymer or carbonaceous material for the positive electrode, anions in the non-aqueous electrolyte are inserted or removed from the positive electrode, and lithium ions in the non-aqueous electrolyte are inserted into the negative electrode made of a carbonaceous material. There is a non-aqueous electrolyte storage element (hereinafter, this type of battery may be referred to as a “dual carbon storage element”) that is charged and discharged by desorption (see, for example, Patent Document 1).

In the dual carbon electricity storage device, as shown in the following reaction formula, an anion such as PF ₆ ⁻ is inserted from the non-aqueous electrolyte to the positive electrode, and Li ⁺ is inserted from the non-aqueous electrolyte to the negative electrode. Thus, charging is performed, and discharging is performed by desorption of an anion such as PF ₆ ⁻ from the positive electrode and Li ⁺ from the negative electrode into the non-aqueous electrolyte.

  The discharge capacity of the dual carbon storage element is determined by the anion storage amount of the positive electrode, the anion release amount of the positive electrode, the cation storage amount of the negative electrode, the cation release amount of the negative electrode, the anion amount in the non-aqueous electrolyte, and the cation amount. . For this reason, in order to increase the discharge capacity in the dual carbon storage element, it is necessary to increase the amount of the non-aqueous electrolyte containing a lithium salt in addition to the positive electrode active material and the negative electrode active material (see, for example, Non-Patent Document 1). ).

  In this way, anions are accumulated from the non-aqueous electrolyte to the positive electrode, and cations are accumulated from the non-aqueous electrolyte to the negative electrode, so that charging is performed, and the anion from the positive electrode and the cation from the negative electrode are released to the non-aqueous electrolyte. A sufficient amount of electrolyte salt is required in a non-aqueous electrolyte storage element that is discharged by the above. Although it is important to increase the volumetric energy density of the electricity storage device, it is important to put the nonaqueous electrolyte in the volume of the restricted nonaqueous electrolyte electricity storage device. If the rate is increased, there is a problem that the contact between the active material particles decreases, and the high-load discharge performance decreases.

In a non-aqueous electrolyte storage element using a lithium storage or emission type positive electrode typified by a composite oxide positive electrode and a lithium storage or emission type negative electrode typified by graphite, the concentration of the electrolyte salt is reduced by charging and discharging. Does not change substantially. For this reason, since the electrode density is set high in order to pack a large amount of power storage material inside the power storage element (in order to increase the energy density of the power storage element), the porosity of the electrode is lowered. When the same configuration as that of the electricity storage device in which the concentration of the electrolyte salt does not substantially change according to such charge and discharge is reduced, the amount of the non-aqueous electrolyte placed in the electricity storage device is reduced, and the concentration of the electrolyte salt is sufficiently reduced. There is a problem that a sufficient charge capacity and discharge capacity cannot be obtained. Furthermore, in order to solve this point, if the thickness of the separator is made too thick to substantially increase the amount of the non-aqueous electrolyte, the amount of separators that do not contribute to storage increases, and the energy density of the non-aqueous electrolyte storage element increases. There is a problem that it falls.
Furthermore, in a non-aqueous electrolyte storage element using an electrode that stores anions on the positive electrode, the storage element capacity is reduced when the concentration of the electrolyte salt is increased to about 3 mol / L and when high voltage charging is performed. There is a bug.

  Therefore, it is desired to provide a non-aqueous electrolyte storage element that can improve the charge / discharge cycle characteristics and realize high energy density and high load discharge performance.

  An object of the present invention is to provide a non-aqueous electrolyte storage element that can realize high energy density and high load discharge performance and improved cycle characteristics of charge and discharge.

The non-aqueous electrolyte storage element of the present invention as a means for solving the above-described problems includes a positive electrode including a positive electrode material layer containing a positive electrode active material capable of reversibly storing or releasing anions, and a cation reversibly. A negative electrode including a negative electrode material layer containing a negative electrode active material that can be stored or released; a separator between the positive electrode and the negative electrode; and a non-aqueous electrolyte solution containing an electrolyte salt.
A positive electrode including a positive electrode material layer containing a positive electrode active material capable of reversibly accumulating or releasing anions, a negative electrode including a negative electrode material layer containing a negative electrode active material capable of reversibly accumulating or releasing cations, and the positive electrode A non-aqueous electrolyte storage element having a separator and a non-aqueous electrolyte containing an electrolyte salt between the negative electrode and the negative electrode,
The pore volume V1 of the positive electrode material layer per unit area of the positive electrode, the pore volume V2 of the negative electrode material layer per unit area of the negative electrode, the pore volume V3 per unit area of the separator, and the nonaqueous electrolyte storage element Satisfying the following formula, 0.5 ≦ [(V1 + V2 + V3) / V4] ≦ 0.61,
The porosity P1 of the positive electrode material layer and the porosity P2 of the separator satisfy the following expression: 0.14 ≦ P1 / P2 ≦ 0.84.

  ADVANTAGE OF THE INVENTION According to this invention, a high energy density and high load discharge performance can be implement | achieved, and the non-aqueous-electrolyte electrical storage element which improved the cycling characteristics of charging / discharging can be provided.

FIG. 1 is a schematic view showing an example of the nonaqueous electrolyte storage element of the present invention.

(Non-aqueous electrolyte storage element)
The nonaqueous electrolyte storage element of the present invention includes a positive electrode, a negative electrode, a nonaqueous electrolyte, and a separator, and further includes other members as necessary.

  There is no restriction | limiting in particular as said non-aqueous electrolyte electrical storage element, According to the objective, it can select suitably, For example, a non-aqueous electrolyte secondary battery, a non-aqueous electrolyte capacitor, etc. are mentioned.

  As a result of repeated studies by the present inventors in order to solve the above problems, in particular, in an anion intercalation type storage element in which the electrolyte salt concentration of the nonaqueous electrolytic solution is changed by charging and discharging, a high energy density and a high load are obtained. In order to achieve the discharge performance and improve the charge / discharge cycle characteristics, adjust the porosity of the electrode and the porosity of the separator to ensure the conductivity inside the electrode layer, and to ensure a sufficient amount of non-aqueous electrolyte. It is necessary to hold and adjust the distance between the positive and negative electrodes. Therefore, it was found that the porosity of the element that determines the amount of the non-aqueous electrolyte inside is important particularly in an anion intercalation electricity storage element in which the electrolyte salt concentration of the non-aqueous electrolyte changes due to charge and discharge.

In the present invention, in order to achieve high energy density and high load discharge performance, the content of the electrolyte salt in the non-aqueous electrolyte is increased, that is, the volume of the non-aqueous electrolyte stored in the separator is increased. It is necessary to.
The non-aqueous electrolyte can be stored in the pores of the positive electrode material layer (not including the positive electrode current collector), the pores of the negative electrode material layer (not including the negative electrode current collector), and the separator.
Therefore, the pore volume V1 of the positive electrode material layer per unit area of the positive electrode, the pore volume V2 of the negative electrode material layer per unit area of the negative electrode, the pore volume V3 per unit area of the separator, and the non-aqueous electrolyte The total volume V4 of the power storage elements needs to satisfy the following formula, 0.5 ≦ [(V1 + V2 + V3) / V4] ≦ 0.61.
When [(V1 + V2 + V3) / V4] is 0.5 or more, the amount of the non-aqueous electrolyte is appropriate and the capacity can be increased. Further, when [(V1 + V2 + V3) / V4] is 0.61 or less, high energy density and high load discharge performance can be realized. If the concentration of the electrolyte salt is too high or too low, the non-aqueous electrolyte cannot exhibit sufficient performance. By setting the porosity so as to satisfy the above range, it is possible to appropriately adjust the electrolyte salt concentration change of the non-aqueous electrolyte.
When [(V1 + V2 + V3) / V4] is less than 0.5, the electrolyte concentration in the non-aqueous electrolyte is lowered, and the intercalating ions are reduced, so that charging may not be possible. Exceeding may cause a gap in the non-aqueous electrolyte storage element to become large, increase the resistance due to the distance between the electrodes, and charge and discharge at high output may not be possible.
The pore volume of the negative electrode material layer per unit area of the negative electrode is, for example, the pores contained in the negative electrode material layer when the negative electrode material layer is applied and formed on the negative electrode current collector of the negative electrode It means volume. The same applies to the pore volume of the positive electrode material layer per unit area of the positive electrode and the pore volume per unit area of the separator.
Here, the pore volume of the negative electrode material layer per unit area of the negative electrode, the pore volume of the positive electrode material layer per unit area of the positive electrode, and the pore volume of the separator are, for example, a mercury porosimeter or a pycnometer (gas displacement method). ).

The ratio (P1 / P2) between the porosity P1 of the positive electrode material layer and the porosity P2 of the separator needs to be in the following range.
0.14 ≦ P1 / P2 ≦ 0.84
When the ratio (P1 / P2) is 0.14 or more, the amount of the non-aqueous electrolyte in the positive electrode material layer and the distance between the positive and negative electrodes may be appropriate, and the output and life performance may be improved. 0.84 When it is below, the number of holes in the positive electrode material layer, the conductivity in the positive electrode material layer, and the amount of the electrolyte solution in the separator become appropriate, and the output performance is improved.
When the ratio (P1 / P2) is less than 0.14, the amount of the non-aqueous electrolyte inside the positive electrode decreases, and an electrolyte shortage involved in discharge / charge may occur. When the ratio exceeds 0.84, When the inter-particle distance of the positive electrode active material is increased, the resistance may increase and charging / discharging at high output may not be possible.

The porosity of the positive electrode material layer and the porosity of the negative electrode material layer are not particularly limited and may be appropriately selected depending on the intended purpose. However, both are preferably 0.25 or more and 0.65 or less, and the electrolyte salt Is more preferably 0.25 or more and 0.5 or less from the viewpoint of maintaining the strength and securing the strength.
When the porosity is 0.25 or more, the volume in which the nonaqueous electrolytic solution is contained increases. For this reason, it is necessary to reduce the concentration of the electrolyte salt to maintain the storage element capacity.However, the decrease in the concentration of the electrolyte salt reduces the resistance and improves the low-temperature characteristics. Decomposition can be suppressed. Moreover, the intensity | strength of electrode itself is favorable in the said porosity being 0.65 or less.
There is no restriction | limiting in particular in the porosity of the said separator, Although it can select suitably according to the objective, 0.3 or more and 0.8 or less are preferable.
Here, the porosity of the positive electrode material layer, the negative electrode material layer, and the separator is obtained by multiplying the “pore volume” obtained by a mercury porosimeter, a pycnometer, or the like by “the geometric electrode area and the electrode material layer thickness”. It can be calculated by dividing by “volume”.

The anion storage / release amount per unit area of the positive electrode is preferably 0.15 mAh / cm ² or more and 0.60 mAh / cm ² or less. When the amount of anion storage / release per unit area of the positive electrode is 0.15 mAh / cm ² or more, the stability of the charge / discharge cycle is improved, and when it is 0.60 mAh / cm ² or less, the required amount of electrolyte Becomes appropriate and output performance is improved.
The amount of anion occlusion / release per unit area of the positive electrode can be measured, for example, by using metallic lithium for the negative electrode, facing the positive electrode through a separator, and charging / discharging in the electrolytic solution.

Regarding the capacity relationship between the positive electrode and the negative electrode, in order to maintain the stability of repeated charge and discharge, it is important to reduce the decrease in capacity due to the deterioration of the negative electrode, and the capacity per unit area of the negative electrode is the positive electrode It is effective to improve the decrease in discharge capacity associated with repeated charge / discharge cycles.
The capacity ratio (negative electrode capacity C1 / positive electrode capacity C2) is not particularly limited as long as the capacity of the negative electrode is larger, and can be appropriately selected according to the purpose, but is preferably 1.05 or more and 6 or less. When the capacity ratio (negative electrode capacity C1 / positive electrode capacity C2) is 1.05 or less, cycle deterioration accompanied by Li precipitation can be prevented. On the other hand, when the capacity ratio (negative electrode capacity C1 / positive electrode capacity C2) is 6 or less, the capacity can be improved and the cycle characteristics can be maintained by maintaining the amount of the non-aqueous electrolyte, and the energy density of the power storage element itself is improved. .
Here, the capacity per unit area of the positive electrode and the capacity per unit area of the negative electrode can be measured by, for example, a commercially available charging / discharging device. The capacity per unit area is the capacity relative to the geometric area of the electrode. The capacity of the positive electrode can be measured by charging to a predetermined upper limit voltage using lithium as a counter electrode and then discharging to a predetermined voltage. The predetermined voltage generally corresponds to the charge / discharge method when the non-electrolyte storage element of the present invention is configured. The capacity of the negative electrode can be similarly measured.

  Hereinafter, the positive electrode, the negative electrode, the non-aqueous electrolyte, and the separator of the non-aqueous electrolyte storage element of the present invention will be sequentially described.

<Positive electrode>
The positive electrode is not particularly limited as long as it contains a positive electrode active material, and can be appropriately selected according to the purpose. For example, a positive electrode including a positive electrode material layer containing a positive electrode active material on a positive electrode current collector, Etc.
There is no restriction | limiting in particular as a shape of the said positive electrode, According to the objective, it can select suitably, For example, flat form etc. are mentioned.

<< Cathode Material Layer >>
There is no restriction | limiting in particular as said positive electrode material layer, According to the objective, it can select suitably, For example, it contains a positive electrode active material at least, and also contains a electrically conductive agent, a binder, a thickener, etc. as needed. Become.

-Positive electrode active material-
The positive electrode active material is not particularly limited as long as it is a substance capable of reversibly accumulating or releasing anions, and can be appropriately selected according to the purpose. Examples thereof include carbonaceous materials and conductive polymers. Can be mentioned. Among these, a carbonaceous material is particularly preferable because of its high energy density.
Examples of the conductive polymer include polyaniline, polypyrrole, polyparaphenylene, and the like.
Examples of the carbonaceous material include graphite (graphite) such as coke, artificial graphite and natural graphite, and organic pyrolysis products under various pyrolysis conditions. Among these, artificial graphite and natural graphite are particularly preferable.

The carbonaceous material is preferably a carbonaceous material having high crystallinity. The crystallinity can be evaluated by X-ray diffraction, Raman analysis, and the like. For example, in a powder X-ray diffraction pattern using CuKα rays, the diffraction peak intensity I _{2θ = 22.3 ° at 2θ = 22.3 °} The intensity ratio I _{2θ = 22.3 °} / I 2θ = 26.4 ° of the diffraction peak intensity I _{2θ = 26.4 °} at _{2θ = 26.4 °} is preferably 0.4 or less.
The BET specific surface area by nitrogen adsorption of the carbonaceous material is preferably 1 m ² / g or more and 100 m ² / g or less, and the average particle size (median diameter) obtained by the laser diffraction / scattering method is 0.1 μm or more and 100 μm or less. preferable.

-Binder-
The binder is not particularly limited as long as it is a material that is stable with respect to the solvent and electrolyte used in the production of the electrode, and can be appropriately selected according to the purpose. For example, polyvinylidene fluoride (PVDF), polytetra Examples thereof include a fluorine-based binder such as fluoroethylene (PTFE), styrene-butadiene rubber (SBR), isoprene rubber, and the like. These may be used individually by 1 type and may use 2 or more types together.

-Thickener-
Examples of the thickener include carboxymethyl cellulose (CMC), methyl cellulose, hydroxymethyl cellulose, ethyl cellulose, polyvinyl alcohol, oxidized starch, phosphate starch, and casein. These may be used individually by 1 type and may use 2 or more types together.

-Conductive agent-
Examples of the conductive agent include metal materials such as copper and aluminum, and carbonaceous materials such as carbon black and acetylene black. These may be used individually by 1 type and may use 2 or more types together.
There is no restriction | limiting in particular in the average thickness of the said positive electrode material layer, Although it can select suitably according to the objective, 20 micrometers or more and 300 micrometers or less are preferable, and 40 micrometers or more and 150 micrometers or less are more preferable. When the average thickness is less than 20 μm, the energy density may decrease, and when it exceeds 300 μm, the load characteristics may be deteriorated.

<< Positive electrode current collector >>
There is no restriction | limiting in particular as a material, a shape, a magnitude | size, and a structure of the said positive electrode electrical power collector, According to the objective, it can select suitably.
The material of the positive electrode current collector is not particularly limited as long as it is formed of a conductive material, and can be appropriately selected according to the purpose. For example, stainless steel, nickel, aluminum, copper, titanium And tantalum. Among these, stainless steel and aluminum are particularly preferable.
There is no restriction | limiting in particular as a shape of the said positive electrode electrical power collector, According to the objective, it can select suitably.
The size of the positive electrode current collector is not particularly limited as long as it is a size that can be used for a non-aqueous electrolyte storage element, and can be appropriately selected according to the purpose.

-Method for producing positive electrode-
The positive electrode is obtained by applying a positive electrode material composition in a slurry form by adding the binder, the thickener, the conductive agent, a solvent, and the like to the positive electrode active material as necessary. The positive electrode material layer can be formed by drying. There is no restriction | limiting in particular as said solvent, According to the objective, it can select suitably, For example, an aqueous solvent, an organic solvent, etc. are mentioned. Examples of the aqueous solvent include water, alcohol, and the like. Examples of the organic solvent include N-methyl-2-pyrrolidone (NMP), toluene, and the like.
In addition, the positive electrode active material can be roll-formed as it is to form a sheet electrode, or a pellet electrode by compression molding.

<Negative electrode>
The negative electrode is not particularly limited as long as it contains a negative electrode active material, and can be appropriately selected according to the purpose. For example, a negative electrode including a negative electrode material layer containing a negative electrode active material on a negative electrode current collector, etc. Is mentioned.
There is no restriction | limiting in particular as a shape of the said negative electrode, According to the objective, it can select suitably, For example, flat form etc. are mentioned.

<< Anode Material Layer >>
The negative electrode material layer includes at least a negative electrode active material, and further includes a binder, a conductive agent, and the like as necessary.

-Negative electrode active material-
The negative electrode active material is not particularly limited as long as it is a substance capable of reversibly accumulating or releasing cations, and can be appropriately selected according to the purpose. For example, an alkali metal ion, an alkaline earth metal, or Metal oxides that can be occluded or released; alkali metal ions, metals that can be alloyed with alkaline earth metals, alloys containing these metals, composite alloy compounds; non-reactions due to physical adsorption of ions such as carbonaceous materials with a high specific surface area And the like. Among these, a substance capable of reversibly storing or releasing at least one of lithium and lithium ions is preferable in terms of energy density, and a non-reactive electrode is more preferable in terms of cycle characteristics.
Specific examples of the negative electrode active material include carbonaceous materials, lithium titanates, antimony tin oxides, metal oxides capable of inserting and extracting lithium such as silicon monoxide, and lithiums such as aluminum, tin, silicon, and zinc. And a metal alloy or metal alloy that can be alloyed with lithium, a composite alloy compound of lithium and a metal that can be alloyed with lithium and an alloy containing the metal, lithium metal nitride such as cobalt lithium nitride, and the like. These may be used individually by 1 type and may use 2 or more types together. Among these, a carbonaceous material or lithium titanate is particularly preferable from the viewpoint of safety and cost.
Examples of the carbonaceous material include graphite (graphite) such as coke, artificial graphite, and natural graphite, organic pyrolysis products under various pyrolysis conditions, and amorphous carbon. Among these, artificial graphite, natural graphite, and amorphous carbon are particularly preferable. As lithium titanate, Li ₄ Ti ₅ O ₁₂ or a similar compound in which some elements are substituted with Li ₄ Ti ₅ O ₁₂ as a basic skeleton is particularly preferable.

-Binder-
There is no restriction | limiting in particular as said binder, According to the objective, it can select suitably, For example, fluorine-type binders, such as polyvinylidene fluoride (PVDF) and polytetrafluoroethylene (PTFE), ethylene-propylene-butadiene rubber ( EPBR), styrene-butadiene rubber (SBR), isoprene rubber, carboxymethylcellulose (CMC), and the like. These may be used individually by 1 type and may use 2 or more types together.
Among these, fluorine-based binders such as polyvinylidene fluoride (PVDF) and polytetrafluoroethylene (PTFE), and carboxymethyl cellulose (CMC) are preferable, and the CMC is more preferable because the number of repeated charging and discharging is improved as compared with other binders. Particularly preferred.

-Conductive agent-
Examples of the conductive agent include metal materials such as copper and aluminum, and carbonaceous materials such as carbon black and acetylene black. These may be used individually by 1 type and may use 2 or more types together.
There is no restriction | limiting in particular in the average thickness of the said negative electrode material layer, Although it can select suitably according to the objective, 10 micrometers or more and 450 micrometers or less are preferable, and 20 micrometers or more and 100 micrometers or less are more preferable. If the average thickness is less than 10 μm, the cycle characteristics may be deteriorated, and if it exceeds 450 μm, the energy density may be lowered.

<< Negative electrode current collector >>
There is no restriction | limiting in particular as a material, a shape, a magnitude | size, and a structure of the said negative electrode collector, According to the objective, it can select suitably.
The material of the negative electrode current collector is not particularly limited as long as it is formed of a conductive material, and can be appropriately selected according to the purpose. Examples thereof include stainless steel, nickel, aluminum, and copper. Can be mentioned. Among these, stainless steel and copper are particularly preferable.
There is no restriction | limiting in particular as a shape of the said negative electrode electrical power collector, According to the objective, it can select suitably.
The size of the negative electrode current collector is not particularly limited as long as it is a size that can be used for a non-aqueous electrolyte storage element, and can be appropriately selected according to the purpose.

-Negative electrode manufacturing method-
The negative electrode is obtained by applying a negative electrode material composition in a slurry form by adding the binder, the conductive agent, a solvent, or the like to the negative electrode active material as necessary, and drying the negative electrode current collector. A negative electrode material layer can be formed. As the solvent, the same solvent as that for the positive electrode can be used.
Further, the negative electrode active material added with the binder, the conductive agent and the like is roll-formed as it is to form a sheet electrode, a pellet electrode by compression molding, the negative electrode current collector by techniques such as vapor deposition, sputtering, and plating. A thin film of the negative electrode active material can be formed on the body.

<Non-aqueous electrolyte>
The nonaqueous electrolytic solution is an electrolytic solution containing a nonaqueous solvent and an electrolyte salt.

<< Non-aqueous solvent >>
There is no restriction | limiting in particular as said non-aqueous solvent, Although it can select suitably according to the objective, An aprotic organic solvent is suitable.
As the aprotic organic solvent, carbonate-based organic solvents such as chain carbonates and cyclic carbonates are used.
Examples of the chain carbonate include dimethyl carbonate (DMC), diethyl carbonate (DEC), methyl ethyl carbonate (EMC), and methyl propionate (MP).

Examples of the cyclic carbonate include propylene carbonate (PC), ethylene carbonate (EC), butylene carbonate (BC), vinylene carbonate (VC), and the like.
When a mixed solvent combining ethylene carbonate (EC) as the cyclic carbonate and dimethyl carbonate (DMC) as the chain carbonate is used, the mixing ratio of ethylene carbonate (EC) and dimethyl carbonate (DMC) is particularly There is no restriction | limiting, According to the objective, it can select suitably.
In addition, as said non-aqueous solvent, ester type organic solvents, such as cyclic ester and chain ester, ether type organic solvents, such as cyclic ether and chain ether, etc. can be used as needed.

Examples of the cyclic ester include γ-butyrolactone (γBL), 2-methyl-γ-butyrolactone, acetyl-γ-butyrolactone, and γ-valerolactone.
Examples of the chain ester include propionic acid alkyl ester, malonic acid dialkyl ester, acetic acid alkyl ester (methyl acetate (MA), ethyl acetate, etc.), formic acid alkyl ester (methyl formate (MF), ethyl formate, etc.) and the like. Can be mentioned.
Examples of the cyclic ether include tetrahydrofuran, alkyltetrahydrofuran, alkoxytetrahydrofuran, dialkoxytetrahydrofuran, 1,3-dioxolane, alkyl-1,3-dioxolane, 1,4-dioxolane, and the like.
Examples of the chain ether include 1,2-dimethoxyethane (DME), diethyl ether, ethylene glycol dialkyl ether, diethylene glycol dialkyl ether, triethylene glycol dialkyl ether, and tetraethylene glycol dialkyl ether.

<< Electrolyte salt >>
The electrolyte salt is not particularly limited as long as it contains a halogen atom, dissolves in a non-aqueous solvent and exhibits high ionic conductivity, and a combination of the following cation and the following anion can be used. It is.
Examples of the cation include alkali metal ions, alkaline earth metal ions, tetraalkylammonium ions, spiro quaternary ammonium ions, and the like.
Examples of the anion include Cl ⁻ , Br ⁻ , I ⁻ , ClO ₄ ⁻ , BF ₄ ⁻ , PF ₆ ⁻ , SbF ₆ ⁻ , CF ₃ SO ₃ ⁻ , (CF ₃ SO ₂ ) ₂ N ⁻ , (C ₂ F ₅ SO ₂ ) ₂ N ⁻ , and the like.
Among the electrolyte salts containing halogen atoms, lithium salts are particularly preferable from the viewpoint of improving battery capacity.

The lithium salt is not particularly limited and may be appropriately selected depending on the intended purpose. For example, lithium hexafluorophosphate (LiPF ₆ ), lithium perchlorate (LiClO ₄ ), lithium chloride (LiCl), boron Lithium fluoride (LiBF ₄ ), lithium hexafluoride arsenic (LiAsF ₆ ), lithium trifluorometasulfonate (LiCF ₃ SO ₃ ), lithium bistrifluoromethylsulfonylimide (LiN (C ₂ F ₅ SO ₂ ) ₂ ), Lithium bisfurfluoroethylsulfonylimide (LiN (CF ₂ F ₅ SO ₂ ) ₂ ), and the like. These may be used individually by 1 type and may use 2 or more types together. Among these, LiPF ₆ is particularly preferable from the viewpoint of the amount of occlusion of anions in the carbon electrode.

  There is no restriction | limiting in particular as content of the said electrolyte salt, Although it can select suitably according to the objective, 1.5 mol / L or more and 4 mol / L or less are preferable in the said nonaqueous solvent, 1.5 mol / L L or more and 3 mol / L or less are more preferable, and 1.5 mol / L or more and 2.5 mol / L or less are more preferable from the point of coexistence of the capacity | capacitance and output of an electrical storage element.

<Separator>
The separator is provided between the positive electrode and the negative electrode in order to prevent a short circuit between the positive electrode and the negative electrode.
There is no restriction | limiting in particular as a material of the said separator, a shape, a magnitude | size, and a structure, According to the objective, it can select suitably.
Examples of the material of the separator include paper such as kraft paper, vinylon mixed paper, synthetic pulp mixed paper, cellophane, polyethylene graft film, polyolefin nonwoven fabric such as polypropylene melt flow nonwoven fabric, polyamide nonwoven fabric, and glass fiber nonwoven fabric. .
Among these, those having a porosity of 50% or more are preferable from the viewpoint of holding the non-aqueous electrolyte.
As the shape of the separator, the non-woven fabric type is preferred from the point of high porosity than the thin-film type having micropores.
There is no restriction | limiting in particular in the average thickness of the said separator, Although it can select suitably according to the objective, 20 micrometers or more and 200 micrometers or less are preferable, and 20 micrometers or more and 100 micrometers or less are more preferable. When the average thickness is 20 μm or more, the retained amount of the electrolytic solution can be increased. Moreover, an energy density increases that it is 200 micrometers or less.
Examples of the shape of the separator include a sheet shape.
There is no restriction | limiting in particular as long as the magnitude | size of the said separator is a magnitude | size which can be used for a non-aqueous electrolyte electrical storage element, It can select suitably according to the objective.
The separator may have a single layer structure or a laminated structure.

<Other members>
There is no restriction | limiting in particular as said other member, According to the objective, it can select suitably, For example, an armored can, an electrode extraction line, etc. are mentioned.

<Method for Manufacturing Nonaqueous Electrolyte Storage Element>
The nonaqueous electrolyte storage element of the present invention can be manufactured by assembling the positive electrode, the negative electrode, the nonaqueous electrolyte, and a separator into an appropriate shape. Furthermore, it is also possible to use other components such as an outer can if necessary. There is no restriction | limiting in particular as a method of assembling the said non-aqueous electrolyte electrical storage element, It can select suitably from the methods employ | adopted normally.

The nonaqueous electrolyte storage element of the present invention is not particularly limited and may be appropriately selected depending on the purpose. The maximum voltage of the positive electrode during charge / discharge is 4.3 V vs Li / Li ⁺ or more and 6.0 V vs. Li / Li ⁺ or less is preferable. When the maximum voltage of the positive electrode during charge / discharge is 4.3 V vs Li / Li ⁺ or more, anions can be accumulated and the capacity increases. Moreover, decomposition | disassembly of a solvent and electrolyte salt does not occur as it is 6.0V vs Li / Li ⁺ or less, and degradation can be prevented.
The maximum voltage of the positive electrode is obtained by taking out the positive electrode in a charged state, using metallic lithium as a negative electrode, placing a separator that can permeate lithium ions between the negative electrode and the positive electrode, and dissolving an electrolyte salt in a non-aqueous solvent. It can be measured by immersing in a non-aqueous electrolyte solution.

  Here, FIG. 1 is a schematic diagram showing an example of the nonaqueous electrolyte storage element of the present invention. This nonaqueous electrolyte storage element 10 includes a positive electrode 1 including a positive electrode active material capable of reversibly storing or releasing anions and a negative electrode active material capable of reversibly storing and releasing cations in an outer can 4. A negative electrode 2 and a separator 3 are accommodated between the positive electrode 1 and the negative electrode 2, and the positive electrode 1, the negative electrode 2, and the separator 3 are non-aqueous electrolytes (non-aqueous electrolytes) obtained by dissolving an electrolyte salt in a non-aqueous solvent. It is immersed in the figure. In addition, 5 is a negative electrode lead wire and 6 is a positive electrode lead wire.

-Shape-
There is no restriction | limiting in particular about the shape of the non-aqueous-electrolyte electrical storage element of this invention, According to the use, it can select suitably from the various shapes generally employ | adopted. Examples of the shape include a laminate type, a cylinder type in which a sheet electrode and a separator are spiral, a cylinder type having an inside-out structure in which a pellet electrode and a separator are combined, and a coin type in which a pellet electrode and a separator are stacked. .

<Application>
The use of the non-aqueous electrolyte storage element of the present invention is not particularly limited and can be used for various purposes. For example, a notebook computer, pen input personal computer, mobile personal computer, electronic book player, mobile phone, mobile fax, mobile phone Copy, portable printer, headphone stereo, video movie, LCD TV, handy cleaner, portable CD, minidisc, walkie-talkie, electronic notebook, calculator, memory card, portable tape recorder, radio, backup, motor, lighting equipment, toy, game machine , Power supplies for watches, strobes, cameras, etc.

  Examples of the present invention will be described below, but the present invention is not limited to these examples.

<Measurement of Porosity of Positive Electrode Material Layer, Negative Electrode Material Layer, and Separator and Their Pore Volume>
The porosity of the positive electrode material layer, the negative electrode material layer, and the separator is measured by measuring the gas absorption amount (pore volume) into the electrode with a Malvern Pycnometer 1200e, and calculating the gas absorption amount (pore volume) as an electrode. It was calculated by dividing by the geometric volume.

<Average thickness of positive electrode material layer and negative electrode material layer>
The average thickness of the positive electrode material layer and the negative electrode material layer is measured by measuring the thickness of the electrode with a micrometer (G2-205, manufactured by Ozaki Manufacturing Co., Ltd.), and subtracting the thickness of the current collector. The thickness of the layer was determined, and the average value of several thicknesses was taken as the average thickness.

<Average thickness of separator>
The average thickness of the separator was measured using a micrometer (manufactured by Ozaki Mfg. Co., Ltd., G2-205), and the average value of the thickness at several locations was taken as the average thickness.

(Production Example 1 of positive electrode)
-Production of positive electrode A-
Graphite powder was used as the positive electrode active material. This graphite powder had a BET specific surface area of 3.0 m ² / g by nitrogen adsorption and an average particle diameter (median diameter) measured by a laser diffraction particle size distribution meter (manufactured by Shimadzu Corporation, SALD-2200) was 8.8 μm. .
Water is added to the graphite powder and the conductive agent (acetylene black) and kneaded. Further, a 2% by weight aqueous solution of carboxymethyl cellulose (CMC) is added as a thickener and kneaded, and further a binder (styrene-butadiene rubber (SBR)). ) Was added to prepare a positive electrode material layer composition (slurry). The solid content mass ratio of the positive electrode material layer was graphite powder: conductive aid: thickening material: binder = 93: 5: 1: 1. The positive electrode material composition was applied to an aluminum foil and vacuum dried at 150 ° C. for 12 hours to form a positive electrode material layer. This was punched into a round shape with a diameter of 16 mm to produce a positive electrode A. At this time, the mass per unit area of the carbon powder (graphite) in the positive electrode material layer coated on the aluminum (Al) foil having a diameter of 16 mm is 10 mg / cm ² , the average thickness of the positive electrode material layer is 125 μm, and the positive electrode material layer The porosity was 0.65.

(Production Example 2 of positive electrode)
-Production of positive electrode B-
The produced positive electrode A was compressed using a press machine (manufactured by Tester Sangyo Co., Ltd.) to produce a positive electrode B having an average thickness of the positive electrode material layer of 100 μm. The porosity of the positive electrode material layer was 0.56.

(Production Example 3 of Positive Electrode)
-Production of positive electrode C-
The produced positive electrode A was compressed using a press machine (manufactured by Tester Sangyo Co., Ltd.) to produce a positive electrode C having a positive electrode material layer with an average thickness of 76.9 μm. The porosity of the positive electrode material layer was 0.42.

(Production Example 4 of Positive Electrode)
-Production of positive electrode D-
The produced positive electrode A was compressed using a press machine (manufactured by Tester Sangyo Co., Ltd.) to produce a positive electrode C having a positive electrode material layer with an average thickness of 62.5 μm. The porosity of the positive electrode material layer was 0.29.

(Production Example 5 of positive electrode)
-Production of positive electrode E-
The produced positive electrode A was compressed using a press machine (manufactured by Tester Sangyo Co., Ltd.) to produce a positive electrode C having a positive electrode material layer with an average thickness of 58.8 μm. The porosity of the positive electrode material layer was 0.25.

(Production Example 6 of positive electrode)
-Production of positive electrode F-
Graphite powder was used as the positive electrode active material. This graphite powder had a BET specific surface area of 3.0 m ² / g by nitrogen adsorption and an average particle diameter (median diameter) measured by a laser diffraction particle size distribution meter (manufactured by Shimadzu Corporation, SALD-2200) was 8.8 μm. .
Water is added to the graphite powder and the conductive agent (acetylene black) and kneaded. Further, a 2% by weight aqueous solution of carboxymethyl cellulose (CMC) is added as a thickener and kneaded, and further a binder (styrene-butadiene rubber (SBR)). A positive electrode material layer composition (slurry) was prepared, and the solid content mass ratio of the positive electrode material layer was set to graphite powder: conductive aid: thickening material: binder = 93: 5: 1: 1. The positive electrode material composition was applied to an aluminum foil and vacuum-dried at 150 ° C. for 12 hours to form a positive electrode material layer, which was punched into a round shape with a diameter of 16 mm to produce a positive electrode F.
At this time, the mass per unit area of the carbon powder (graphite) in the positive electrode material layer coated on the aluminum (Al) foil having a diameter of 16 mm is 3 mg / cm ² , the average thickness of the positive electrode material layer is 37.5 μm, and the positive electrode The porosity of the material layer was 0.65.

(Production Example 7 of positive electrode)
-Production of positive electrode G-
The produced positive electrode F was compressed using a press machine (manufactured by Tester Sangyo Co., Ltd.) to produce a positive electrode G having an average thickness of the positive electrode material layer of 30 μm. The porosity of the positive electrode material layer was 0.56.

(Production Example 8 of positive electrode)
-Production of positive electrode H-
The produced positive electrode F was compressed using a press machine (manufactured by Tester Sangyo Co., Ltd.) to produce a positive electrode H having a positive electrode material layer having an average thickness of 23.1 μm. The porosity of the positive electrode material layer was 0.42.

(Production Example 9 of positive electrode)
-Production of positive electrode I-
The produced positive electrode F was compressed using a press machine (manufactured by Tester Sangyo Co., Ltd.) to produce a positive electrode D having an average thickness of the positive electrode material layer of 18.8 μm. The porosity of the positive electrode material layer was 0.29.

(Production Example 10 of positive electrode)
-Production of positive electrode J-
The produced positive electrode F was compressed using a press machine (manufactured by Tester Sangyo Co., Ltd.) to produce a positive electrode J having an average thickness of the positive electrode material layer of 17.6 μm. The porosity of the positive electrode material layer was 0.25.

(Negative electrode production example 1)
-Production of negative electrode A-
Lithium titanate was used as the negative electrode active material. This lithium titanate powder has a BET specific surface area of 7.0 m ² / g by nitrogen adsorption and an average particle diameter (median diameter) measured by a laser diffraction particle size distribution meter (SALD-2200, manufactured by Shimadzu Corporation) is 6.5 μm. Met.
Water is added to the lithium titanate and the conductive agent (acetylene black) and kneaded. Further, a 2% by weight aqueous solution of carboxymethyl cellulose (CMC) is added as a thickener and kneaded, and further a binder (styrene-butadiene rubber). (SBR)) was added to prepare a negative electrode material layer composition (slurry). The solid content mass ratio of the negative electrode material layer was lithium titanate: conducting aid: thickening material: binder = 93: 5: 1: 1. The negative electrode material layer composition was coated on an Al foil and vacuum dried at 150 ° C. for 12 hours to form a negative electrode material layer. This was punched into a round shape with a diameter of 16 mm to obtain a negative electrode A.
At this time, the mass per unit area of the lithium titanate powder in the negative electrode material layer coated on the Al foil having a diameter of 16 mm was 10 mg / cm ² , the average thickness of the negative electrode material layer was 76.9 μm, and the pores of the negative electrode material layer The rate was 0.63.

(Negative electrode production example 2)
-Production of negative electrode B-
The produced negative electrode A was compressed using a press machine (manufactured by Tester Sangyo Co., Ltd.) to produce a negative electrode B having an average thickness of the negative electrode material layer of 62.5 μm. The porosity of the negative electrode material layer was 0.54.

(Negative electrode production example 3)
-Production of negative electrode C-
The produced negative electrode A was compressed using a press machine (manufactured by Tester Sangyo Co., Ltd.) to produce a negative electrode C having a negative electrode material layer with an average thickness of 55.6 μm. The porosity of the negative electrode material layer was 0.48.

(Negative electrode production example 4)
-Production of negative electrode D-
The produced negative electrode A was compressed using a press machine (manufactured by Tester Sangyo Co., Ltd.) to produce a negative electrode D having a negative electrode material layer having an average thickness of 50.0 μm. The porosity of the negative electrode material layer was 0.43.

(Negative electrode production example 5)
-Production of negative electrode E-
The produced negative electrode A was compressed using a press machine (manufactured by Tester Sangyo Co., Ltd.) to produce a negative electrode E having a negative electrode material layer with an average thickness of 45.5 μm. The porosity of the negative electrode material layer was 0.37.

(Negative electrode production example 6)
-Production of negative electrode F-
Lithium titanate was used as the negative electrode active material. This lithium titanate powder has a BET specific surface area of 7.0 m ² / g by nitrogen adsorption and an average particle diameter (median diameter) measured by a laser diffraction particle size distribution meter (SALD-2200, manufactured by Shimadzu Corporation) is 6.5 μm. Met.
Water is added to the lithium titanate and the conductive agent (acetylene black) and kneaded. Further, a 2% by weight aqueous solution of carboxymethyl cellulose (CMC) is added as a thickener and kneaded, and further a binder (styrene-butadiene rubber). (SBR)) was added to prepare a negative electrode material layer composition (slurry). The solid content mass ratio of the negative electrode material layer was lithium titanate: conducting aid: thickening material: binder = 93: 5: 1: 1. The negative electrode material layer composition was coated on an Al foil and vacuum dried at 150 ° C. for 12 hours to form a negative electrode material layer. This was punched into a round shape with a diameter of 16 mm to obtain a negative electrode F.
At this time, the mass per unit area of the lithium titanate powder in the negative electrode material layer coated on the Al foil having a diameter of 16 mm was 3 mg / cm ² , the average thickness of the negative electrode material layer was 23.1 μm, and the pores of the negative electrode material layer The rate was 0.63.

(Negative electrode production example 7)
-Production of negative electrode G-
The produced negative electrode F was compressed using a press machine (manufactured by Tester Sangyo Co., Ltd.) to produce a negative electrode G having an average thickness of the negative electrode material layer of 18.8 μm. The porosity of the negative electrode material layer was 0.54.

(Negative electrode production example 8)
-Production of negative electrode H-
The produced negative electrode F was compressed using a press (manufactured by Tester Sangyo Co., Ltd.) to produce a negative electrode H having a negative electrode material layer having an average thickness of 16.7 μm. The porosity of the negative electrode material layer was 0.48.

(Negative electrode production example 9)
-Production of negative electrode I-
The prepared negative electrode F was compressed using a press (manufactured by Tester Sangyo Co., Ltd.) to prepare a negative electrode I having a negative electrode material layer with an average thickness of 15.0 μm. The porosity of the negative electrode material layer was 0.43.

(Negative electrode production example 10)
-Production of negative electrode J-
The produced negative electrode F was compressed using a press machine (manufactured by Tester Sangyo Co., Ltd.) to produce a negative electrode J having an average thickness of the negative electrode material layer of 13.6 μm. The porosity of the negative electrode material layer was 0.37.

<Preparation of nonaqueous electrolyte storage element>
The positive electrode, the separator, the negative electrode, and the non-aqueous electrolyte solution are placed in a coin-type electric storage element manufacturing can (2032 type, manufactured by Hosen Co., Ltd.), and the can is caulked with a caulking device (Hosen Co., Ltd.). A nonaqueous electrolyte storage element was produced.

<Volume of nonaqueous electrolyte storage element>
The volume of the nonaqueous electrolyte storage element was calculated from the area surrounded by the outermost periphery of the positive electrode, the negative electrode, and the separator as the bottom surface, and the area of the bottom surface × thickness.

Example 1
Put the positive electrode B and the negative electrode B in a coin can, add a non-aqueous electrolyte composed of a non-aqueous solvent (PC: DMC = 1: 1 (volume ratio)) in which 2 mol / L LiPF ₆ is dissolved, A separator having an average thickness of 140 μm and a porosity of 0.67 was inserted between the positive electrode and the negative electrode to assemble the nonaqueous electrolyte storage element of Example 1.
At this time, the pore volume V1 of the positive electrode material layer per unit area of the positive electrode, the pore volume V2 of the negative electrode material layer per unit area of the negative electrode, the pore volume V3 per unit area of the separator, and non-aqueous electrolysis The ratio [(V1 + V2 + V3) / V4] to the total volume V4 of the liquid storage element was 0.60.
The ratio (P1 / P2) between the porosity P1 of the positive electrode material layer and the porosity P2 of the separator was 0.60.

<Capacity maintenance rate after 50 cycles of Evaluation Method 1>
The obtained nonaqueous electrolyte storage element was charged to a charge end voltage of 3.5 V at a constant current of 0.2 mA / cm ² at room temperature (25 ° C.). After the first charge, initial charge / discharge was performed by discharging to 1.7 V with a constant current of 0.2 mA / cm ² . Then, the storage element after the initial charge / discharge is charged at a constant current of 0.2 mA / cm ² to 3.5 V, and then discharged to 1.7 V at a constant current of 0.2 mA / cm ^2. The current discharge was one cycle, and the charge / discharge cycle was performed up to 50 cycles. This evaluation method was designated as evaluation method 1. In addition, it measured using the charging / discharging measuring apparatus (Toyo System Co., Ltd. make, TOSCAT3001).
The capacity maintenance rate after 50 cycles was calculated based on the second discharge capacity as a reference (100%), and evaluated according to the following criteria.
[Evaluation criteria]
○: Capacity maintenance rate after 50 cycles 70% or more ×: Capacity maintenance rate after 50 cycles less than 70%

<Capacity maintenance rate after 50 cycles of Evaluation Method 2>
Using the nonaqueous electrolyte storage element of Example 1, the storage element after the initial charge / discharge was charged at a constant current of 5.0 mA / cm ² to 3.5 V, and then 5.0 mA / cm. ^The constant current discharge which discharges to 1.7V with the constant current of ² was made into 1 cycle, and the charging / discharging cycle was performed to 50 cycles. This evaluation method was referred to as Evaluation Method 2. In addition, it measured using the charging / discharging measuring apparatus (Toyo System Co., Ltd. make, TOSCAT3001).
The capacity maintenance rate after 50 cycles was calculated based on the second discharge capacity as a reference (100%), and evaluated according to the following criteria.
[Evaluation criteria]
○: Capacity maintenance rate after 50 cycles 70% or more ×: Capacity maintenance rate after 50 cycles less than 70%

  As a result, the capacity retention rate after 50 cycles determined by the evaluation method 1 was 93.0%. The capacity retention ratio after 50 cycles determined by the evaluation method 2 was 72.1%. The results are shown in Table 2.

(Example 2)
Put the positive electrode C and the negative electrode B in a coin can, add a non-aqueous electrolyte composed of a non-aqueous solvent (PC: DMC = 1: 1 (volume ratio)) in which 2 mol / L LiPF ₆ is dissolved, A separator having an average thickness of 170 μm and a porosity of 0.67 was inserted between the positive electrode and the negative electrode to assemble the nonaqueous electrolyte storage element of Example 2.
At this time, the pore volume V1 of the positive electrode material layer per unit area of the positive electrode, the pore volume V2 of the negative electrode material layer per unit area of the negative electrode, the pore volume V3 per unit area of the separator, and non-aqueous electrolysis The ratio [(V1 + V2 + V3) / V4] with the total volume V4 of the liquid storage element was 0.58.
The ratio (P1 / P2) between the porosity P1 of the positive electrode material layer and the porosity P2 of the separator was 0.29.
About the obtained non-aqueous electrolyte electrical storage element, it carried out similarly to Example 1, and performed the charging / discharging cycle. As a result, the capacity retention ratio after 50 cycles of Evaluation Method 1 obtained in the same manner as in Example 1 was 91.4%, and the capacity retention ratio after 50 cycles of Evaluation Method 2 was 78.2%. The results are shown in Table 2.

(Example 3)
Put the positive electrode D and the negative electrode B in a coin can, add a non-aqueous electrolyte composed of a non-aqueous solvent (PC: DMC = 1: 1 (volume ratio)) in which 2 mol / L LiPF ₆ is dissolved, A separator having an average thickness of 180 μm and a porosity of 0.67 was inserted between the positive electrode and the negative electrode to assemble the nonaqueous electrolyte storage element of Example 3.
At this time, the pore volume V1 of the positive electrode material layer per unit area of the positive electrode, the pore volume V2 of the negative electrode material layer per unit area of the negative electrode, the pore volume V3 per unit area of the separator, and non-aqueous electrolysis The ratio [(V1 + V2 + V3) / V4] with the total volume V4 of the liquid storage element was 0.56.
The ratio (P1 / P2) between the porosity P1 of the positive electrode material layer and the porosity P2 of the separator was 0.15.
About the obtained non-aqueous electrolyte electrical storage element, it carried out similarly to Example 1, and performed the charging / discharging cycle. As a result, the capacity retention ratio after 50 cycles of Evaluation Method 1 obtained in the same manner as in Example 1 was 90.8%, and the capacity retention ratio after 50 cycles of Evaluation Method 2 was 82.2%. The results are shown in Table 2.

Example 4
Put the positive electrode B and the negative electrode C in a coin can, add a non-aqueous electrolyte composed of a non-aqueous solvent (PC: DMC = 1: 1 (volume ratio)) in which 2 mol / L LiPF ₆ is dissolved, A separator having an average thickness of 150 μm and a porosity of 0.67 was inserted between the positive electrode and the negative electrode to assemble the nonaqueous electrolyte storage element of Example 4.
At this time, the pore volume V1 of the positive electrode material layer per unit area of the positive electrode, the pore volume V2 of the negative electrode material layer per unit area of the negative electrode, the pore volume V3 per unit area of the separator, and non-aqueous electrolysis The ratio [(V1 + V2 + V3) / V4] to the total volume V4 of the liquid storage element was 0.60.
The ratio (P1 / P2) between the porosity P1 of the positive electrode material layer and the porosity P2 of the separator was 0.56.
About the obtained non-aqueous electrolyte electrical storage element, it carried out similarly to Example 1, and performed the charging / discharging cycle. As a result, the capacity retention ratio after 50 cycles of Evaluation Method 1 obtained in the same manner as in Example 1 was 89.8%, and the capacity retention ratio after 50 cycles of Evaluation Method 2 was 75.3%. The results are shown in Table 2.

(Example 5)
Put the positive electrode C and the negative electrode C in a coin can, add a non-aqueous electrolyte composed of a non-aqueous solvent (PC: DMC = 1: 1 (volume ratio)) in which 2 mol / L LiPF ₆ is dissolved, A separator having an average thickness of 170 μm and a porosity of 0.67 was inserted between the positive electrode and the negative electrode to assemble the nonaqueous electrolyte storage element of Example 5.
At this time, the pore volume V1 of the positive electrode material layer per unit area of the positive electrode, the pore volume V2 of the negative electrode material layer per unit area of the negative electrode, the pore volume V3 per unit area of the separator, and non-aqueous electrolysis The ratio [(V1 + V2 + V3) / V4] with the total volume V4 of the liquid storage element was 0.57.
The ratio (P1 / P2) between the porosity P1 of the positive electrode material layer and the porosity P2 of the separator was 0.29.
About the obtained non-aqueous electrolyte electrical storage element, it carried out similarly to Example 1, and performed the charging / discharging cycle. As a result, the capacity retention ratio after 50 cycles of Evaluation Method 1 obtained in the same manner as in Example 1 was 91.7%, and the capacity retention ratio after 50 cycles of Evaluation Method 2 was 80.1%. The results are shown in Table 2.

(Example 6)
Put the positive electrode D and the negative electrode C in a coin can, add a non-aqueous electrolyte composed of a non-aqueous solvent (PC: DMC = 1: 1 (volume ratio)) in which 2 mol / L LiPF ₆ is dissolved, A separator having an average thickness of 190 μm and a porosity of 0.67 was inserted between the positive electrode and the negative electrode to assemble the nonaqueous electrolyte storage element of Example 6.
At this time, the pore volume V1 of the positive electrode material layer per unit area of the positive electrode, the pore volume V2 of the negative electrode material layer per unit area of the negative electrode, the pore volume V3 per unit area of the separator, and non-aqueous electrolysis The ratio [(V1 + V2 + V3) / V4] with the total volume V4 of the liquid storage element was 0.56.
The ratio (P1 / P2) between the porosity P1 of the positive electrode material layer and the porosity P2 of the separator was 0.14.
About the obtained non-aqueous electrolyte electrical storage element, it carried out similarly to Example 1, and performed the charging / discharging cycle. As a result, the capacity retention ratio after 50 cycles of Evaluation Method 1 obtained in the same manner as in Example 1 was 93.3%, and the capacity retention ratio after 50 cycles of Evaluation Method 2 was 84.6%. The results are shown in Table 2.

(Example 7)
Put the positive electrode B and the negative electrode D in a coin can, add a non-aqueous electrolyte composed of a non-aqueous solvent (PC: DMC = 1: 1 (volume ratio)) in which 2 mol / L LiPF ₆ is dissolved, A separator having an average thickness of 160 μm and a porosity of 0.67 was inserted between the positive electrode and the negative electrode to assemble the nonaqueous electrolyte storage element of Example 7.
At this time, the pore volume V1 of the positive electrode material layer per unit area of the positive electrode, the pore volume V2 of the negative electrode material layer per unit area of the negative electrode, the pore volume V3 per unit area of the separator, and non-aqueous electrolysis The ratio [(V1 + V2 + V3) / V4] with the total volume V4 of the liquid storage element was 0.59.
The ratio (P1 / P2) between the porosity P1 of the positive electrode material layer and the porosity P2 of the separator was 0.52.
About the obtained non-aqueous electrolyte electrical storage element, it carried out similarly to Example 1, and performed the charging / discharging cycle. As a result, the capacity retention ratio after 50 cycles of Evaluation Method 1 obtained in the same manner as in Example 1 was 91.5%, and the capacity retention ratio after 50 cycles of Evaluation Method 2 was 78.4%. The results are shown in Table 2.

(Example 8)
Put the positive electrode C and the negative electrode D in a coin can, add a non-aqueous electrolyte composed of a non-aqueous solvent (PC: DMC = 1: 1 (volume ratio)) in which 2 mol / L LiPF ₆ is dissolved, A separator having an average thickness of 180 μm and a porosity of 0.67 was inserted between the positive electrode and the negative electrode to assemble the nonaqueous electrolyte storage element of Example 8.
At this time, the pore volume V1 of the positive electrode material layer per unit area of the positive electrode, the pore volume V2 of the negative electrode material layer per unit area of the negative electrode, the pore volume V3 per unit area of the separator, and non-aqueous electrolysis The ratio [(V1 + V2 + V3) / V4] with the total volume V4 of the liquid storage element was 0.57.
The ratio (P1 / P2) between the porosity P1 of the positive electrode material layer and the porosity P2 of the separator was 0.27.
About the obtained non-aqueous electrolyte electrical storage element, it carried out similarly to Example 1, and performed the charging / discharging cycle. As a result, the capacity retention ratio after 50 cycles of Evaluation Method 1 obtained in the same manner as in Example 1 was 92.2%, and the capacity retention ratio after 50 cycles of Evaluation Method 2 was 83.1%. The results are shown in Table 2.

Example 9
Put the positive electrode D and the negative electrode D in a coin can, add a non-aqueous electrolyte composed of a non-aqueous solvent (PC: DMC = 1: 1 (volume ratio)) in which 2 mol / L LiPF ₆ is dissolved, A separator having an average thickness of 200 μm and a porosity of 0.67 was inserted between the positive electrode and the negative electrode to assemble the nonaqueous electrolyte storage element of Example 9.
At this time, the pore volume V1 of the positive electrode material layer per unit area of the positive electrode, the pore volume V2 of the negative electrode material layer per unit area of the negative electrode, the pore volume V3 per unit area of the separator, and non-aqueous electrolysis The ratio [(V1 + V2 + V3) / V4] to the total volume V4 of the liquid electricity storage element was 0.55.
The ratio (P1 / P2) between the porosity P1 of the positive electrode material layer and the porosity P2 of the separator was 0.14.
About the obtained non-aqueous electrolyte electrical storage element, it carried out similarly to Example 1, and performed the charging / discharging cycle. As a result, the capacity retention ratio after 50 cycles of Evaluation Method 1 obtained in the same manner as in Example 1 was 90.1%, and the capacity retention ratio after 50 cycles of Evaluation Method 2 was 83.8%. The results are shown in Table 2.

(Comparative Example 1)
Put the positive electrode A and the negative electrode B in a coin can, add a non-aqueous electrolyte composed of a non-aqueous solvent (PC: DMC = 1: 1 (volume ratio)) in which 2 mol / L LiPF ₆ is dissolved, A separator having an average thickness of 140 μm and a porosity of 0.67 was inserted between the positive electrode and the negative electrode to assemble the nonaqueous electrolyte storage element of Comparative Example 1.
At this time, the pore volume V1 of the positive electrode material layer per unit area of the positive electrode, the pore volume V2 of the negative electrode material layer per unit area of the negative electrode, the pore volume V3 per unit area of the separator, and non-aqueous electrolysis The ratio [(V1 + V2 + V3) / V4] to the total volume V4 of the liquid storage element was 0.63.
The ratio (P1 / P2) between the porosity P1 of the positive electrode material layer and the porosity P2 of the separator was 0.87.
About the obtained non-aqueous electrolyte electrical storage element, it carried out similarly to Example 1, and performed the charging / discharging cycle. As a result, the capacity retention rate after 50 cycles of Evaluation Method 1 obtained in the same manner as in Example 1 was 90.6%, and the capacity retention rate after 50 cycles of Evaluation Method 2 was 67.1%. The results are shown in Table 2.

(Comparative Example 2)
Put the positive electrode B and the negative electrode A in a coin can, and add a non-aqueous electrolyte composed of a non-aqueous solvent (PC: DMC = 1: 1 (volume ratio)) in which 2 mol / L LiPF ₆ is dissolved, A separator having a mean thickness of 140 μm and a porosity of 0.67 was inserted between the positive electrode and the negative electrode to assemble the nonaqueous electrolyte storage element of Comparative Example 2.
At this time, the pore volume V1 of the positive electrode material layer per unit area of the positive electrode, the pore volume V2 of the negative electrode material layer per unit area of the negative electrode, the pore volume V3 per unit area of the separator, and non-aqueous electrolysis The ratio [(V1 + V2 + V3) / V4] to the total volume V4 of the liquid storage element was 0.62.
The ratio (P1 / P2) between the porosity P1 of the positive electrode material layer and the porosity P2 of the separator was 0.60.
About the obtained non-aqueous electrolyte electrical storage element, it carried out similarly to Example 1, and performed the charging / discharging cycle. As a result, the capacity retention ratio after 50 cycles of Evaluation Method 1 obtained in the same manner as in Example 1 was 74.3%, and the capacity retention ratio after 50 cycles of Evaluation Method 2 was 68.3%. The results are shown in Table 2.

(Comparative Example 3)
Put the positive electrode E and the negative electrode D in a coin can, add a non-aqueous electrolyte composed of a non-aqueous solvent (PC: DMC = 1: 1 (volume ratio)) in which 2 mol / L LiPF ₆ is dissolved, A separator having a mean thickness of 200 μm and a porosity of 0.67 was inserted between the positive electrode and the negative electrode to assemble the nonaqueous electrolyte storage element of Comparative Example 3.
At this time, the pore volume V1 of the positive electrode material layer per unit area of the positive electrode, the pore volume V2 of the negative electrode material layer per unit area of the negative electrode, the pore volume V3 per unit area of the separator, and non-aqueous electrolysis The ratio [(V1 + V2 + V3) / V4] to the total volume V4 of the liquid electricity storage element was 0.55.
The ratio (P1 / P2) between the porosity P1 of the positive electrode material layer and the porosity P2 of the separator was 0.11.
About the obtained non-aqueous electrolyte electrical storage element, it carried out similarly to Example 1, and performed the charging / discharging cycle. As a result, the capacity retention ratio after 50 cycles of Evaluation Method 1 obtained in the same manner as in Example 1 was 74.3%, and the capacity retention ratio after 50 cycles of Evaluation Method 2 was 68.3%. The results are shown in Table 2.

(Comparative Example 4)
Put the positive electrode E and the negative electrode E in a coin can and add a non-aqueous electrolyte composed of a non-aqueous solvent (PC: DMC = 1: 1 (volume ratio)) in which 2 mol / L LiPF ₆ is dissolved, A separator having a mean thickness of 200 μm and a porosity of 0.67 was inserted between the positive electrode and the negative electrode to assemble the nonaqueous electrolyte storage element of Comparative Example 4.
At this time, the pore volume V1 of the positive electrode material layer per unit area of the positive electrode, the pore volume V2 of the negative electrode material layer per unit area of the negative electrode, the pore volume V3 per unit area of the separator, and non-aqueous electrolysis The ratio [(V1 + V2 + V3) / V4] with the total volume V4 of the liquid electricity storage element was 0.54.
The ratio (P1 / P2) between the porosity P1 of the positive electrode material layer and the porosity P2 of the separator was 0.11.
About the obtained non-aqueous electrolyte electrical storage element, it carried out similarly to Example 1, and performed the charging / discharging cycle. As a result, the capacity retention ratio after 50 cycles of Evaluation Method 1 obtained in the same manner as in Example 1 was 65.1%, and the capacity retention ratio after 50 cycles of Evaluation Method 2 was 55.2%. The results are shown in Table 2.

(Comparative Example 5)
Put the positive electrode D and the negative electrode D in a coin can, add a non-aqueous electrolyte composed of a non-aqueous solvent (PC: DMC = 1: 1 (volume ratio)) in which 2 mol / L LiPF ₆ is dissolved, A separator having a mean thickness of 700 μm and a porosity of 0.67 was inserted between the positive electrode and the negative electrode to assemble a nonaqueous electrolyte storage element of Comparative Example 5.
At this time, the pore volume V1 of the positive electrode material layer per unit area of the positive electrode, the pore volume V2 of the negative electrode material layer per unit area of the negative electrode, the pore volume V3 per unit area of the separator, and non-aqueous electrolysis The ratio [(V1 + V2 + V3) / V4] to the total volume V4 of the liquid storage element was 0.62.
The ratio (P1 / P2) between the porosity P1 of the positive electrode material layer and the porosity P2 of the separator was 0.04.
About the obtained non-aqueous electrolyte electrical storage element, it carried out similarly to Example 1, and performed the charging / discharging cycle. As a result, the capacity retention ratio after 50 cycles of Evaluation Method 1 obtained in the same manner as in Example 1 was 89.2%, and the capacity retention ratio after 50 cycles of Evaluation Method 2 was 69.1%. The results are shown in Table 2.

(Example 10)
Put the positive electrode G and the negative electrode G in a coin can, and add a non-aqueous electrolyte composed of a non-aqueous solvent (PC: DMC = 1: 1 (volume ratio)) in which 2 mol / L LiPF ₆ is dissolved, A separator having an average thickness of 50 μm and a porosity of 0.67 was inserted between the positive electrode and the negative electrode to assemble the nonaqueous electrolyte storage element of Example 10.
At this time, the pore volume V1 of the positive electrode material layer per unit area of the positive electrode, the pore volume V2 of the negative electrode material layer per unit area of the negative electrode, the pore volume V3 per unit area of the separator, and non-aqueous electrolysis The ratio [(V1 + V2 + V3) / V4] with the total volume V4 of the liquid storage element was 0.61.
The ratio (P1 / P2) between the porosity P1 of the positive electrode material layer and the porosity P2 of the separator was 0.50.
About the obtained non-aqueous electrolyte electrical storage element, it carried out similarly to Example 1, and performed the charging / discharging cycle. As a result, the capacity retention rate after 50 cycles determined by Evaluation Method 1 was 90.2%. Further, the capacity retention rate after 50 cycles determined by Evaluation Method 2 was 74.1%. The results are shown in Table 2.

(Example 11)
Put the positive electrode H and the negative electrode G in a coin can, and add a non-aqueous electrolyte composed of a non-aqueous solvent (PC: DMC = 1: 1 (volume ratio)) in which 2 mol / L LiPF ₆ is dissolved, A separator having an average thickness of 50 μm and a porosity of 0.67 was inserted between the positive electrode and the negative electrode to assemble the nonaqueous electrolyte storage element of Example 11.
At this time, the pore volume V1 of the positive electrode material layer per unit area of the positive electrode, the pore volume V2 of the negative electrode material layer per unit area of the negative electrode, the pore volume V3 per unit area of the separator, and non-aqueous electrolysis The ratio [(V1 + V2 + V3) / V4] with the total volume V4 of the liquid storage element was 0.58.
The ratio (P1 / P2) between the porosity P1 of the positive electrode material layer and the porosity P2 of the separator was 0.29.
About the obtained non-aqueous electrolyte electrical storage element, it carried out similarly to Example 1, and performed the charging / discharging cycle. As a result, the capacity retention ratio after 50 cycles of Evaluation Method 1 obtained in the same manner as in Example 1 was 93.3%, and the capacity retention ratio after 50 cycles of Evaluation Method 2 was 79.2%. The results are shown in Table 2.

(Example 12)
Put the positive electrode I and the negative electrode G in a coin can, and add a non-aqueous electrolyte composed of a non-aqueous solvent (PC: DMC = 1: 1 (volume ratio)) in which 2 mol / L LiPF ₆ is dissolved, A separator having an average thickness of 60 μm and a porosity of 0.67 was inserted between the positive electrode and the negative electrode to assemble the nonaqueous electrolyte storage element of Example 12.
At this time, the pore volume V1 of the positive electrode material layer per unit area of the positive electrode, the pore volume V2 of the negative electrode material layer per unit area of the negative electrode, the pore volume V3 per unit area of the separator, and non-aqueous electrolysis The ratio [(V1 + V2 + V3) / V4] with the total volume V4 of the liquid storage element was 0.57.
The ratio (P1 / P2) between the porosity P1 of the positive electrode material layer and the porosity P2 of the separator was 0.14.
About the obtained non-aqueous electrolyte electrical storage element, it carried out similarly to Example 1, and performed the charging / discharging cycle. As a result, the capacity retention ratio after 50 cycles of Evaluation Method 1 obtained in the same manner as in Example 1 was 93.1%, and the capacity retention ratio after 50 cycles of Evaluation Method 2 was 84.8%. The results are shown in Table 2.

(Example 13)
Put the positive electrode G and the negative electrode H in a coin can, and add a non-aqueous electrolyte composed of a non-aqueous solvent (PC: DMC = 1: 1 (volume ratio)) in which 2 mol / L LiPF ₆ is dissolved, A separator having an average thickness of 50 μm and a porosity of 0.67 was inserted between the positive electrode and the negative electrode to assemble the nonaqueous electrolyte storage element of Example 13.
At this time, the pore volume V1 of the positive electrode material layer per unit area of the positive electrode, the pore volume V2 of the negative electrode material layer per unit area of the negative electrode, the pore volume V3 per unit area of the separator, and non-aqueous electrolysis The ratio [(V1 + V2 + V3) / V4] to the total volume V4 of the liquid storage element was 0.60.
The ratio (P1 / P2) between the porosity P1 of the positive electrode material layer and the porosity P2 of the separator was 0.50.
About the obtained non-aqueous electrolyte electrical storage element, it carried out similarly to Example 1, and performed the charging / discharging cycle. As a result, the capacity retention ratio after 50 cycles of Evaluation Method 1 obtained in the same manner as in Example 1 was 90.1%, and the capacity retention ratio after 50 cycles of Evaluation Method 2 was 76.1%. The results are shown in Table 2.

(Example 14)
Put the positive electrode H and the negative electrode H in a coin can, add a non-aqueous electrolyte composed of a non-aqueous solvent (PC: DMC = 1: 1 (volume ratio)) in which 2 mol / L LiPF ₆ is dissolved, A separator having an average thickness of 60 μm and a porosity of 0.67 was inserted between the positive electrode and the negative electrode to assemble the nonaqueous electrolyte storage element of Example 14.
At this time, the pore volume V1 of the positive electrode material layer per unit area of the positive electrode, the pore volume V2 of the negative electrode material layer per unit area of the negative electrode, the pore volume V3 per unit area of the separator, and non-aqueous electrolysis The ratio [(V1 + V2 + V3) / V4] with the total volume V4 of the liquid storage element was 0.58.
The ratio (P1 / P2) between the porosity P1 of the positive electrode material layer and the porosity P2 of the separator was 0.25.
About the obtained non-aqueous electrolyte electrical storage element, it carried out similarly to Example 1, and performed the charging / discharging cycle. As a result, the capacity retention ratio after 50 cycles of Evaluation Method 1 obtained in the same manner as in Example 1 was 91.5%, and the capacity retention ratio after 50 cycles of Evaluation Method 2 was 81.4%. The results are shown in Table 2.

(Example 15)
Put the positive electrode I and the negative electrode H in a coin can, add a non-aqueous electrolyte composed of a non-aqueous solvent (PC: DMC = 1: 1 (volume ratio)) in which 2 mol / L LiPF ₆ is dissolved, A separator having an average thickness of 60 μm and a porosity of 0.67 was inserted between the positive electrode and the negative electrode to assemble the nonaqueous electrolyte storage element of Example 15.
At this time, the pore volume V1 of the positive electrode material layer per unit area of the positive electrode, the pore volume V2 of the negative electrode material layer per unit area of the negative electrode, the pore volume V3 per unit area of the separator, and non-aqueous electrolysis The ratio [(V1 + V2 + V3) / V4] with the total volume V4 of the liquid storage element was 0.56.
The ratio (P1 / P2) between the porosity P1 of the positive electrode material layer and the porosity P2 of the separator was 0.14.
About the obtained non-aqueous electrolyte electrical storage element, it carried out similarly to Example 1, and performed the charging / discharging cycle. As a result, the capacity retention ratio after 50 cycles of Evaluation Method 1 obtained in the same manner as in Example 1 was 90.7%, and the capacity retention ratio after 50 cycles of Evaluation Method 2 was 86.6%. The results are shown in Table 2.

(Example 16)
Put the positive electrode G and the negative electrode I in a coin can, and add a non-aqueous electrolyte composed of a non-aqueous solvent (PC: DMC = 1: 1 (volume ratio)) in which 2 mol / L LiPF ₆ is dissolved, A separator having an average thickness of 50 μm and a porosity of 0.67 was inserted between the positive electrode and the negative electrode to assemble the nonaqueous electrolyte storage element of Example 16.
At this time, the pore volume V1 of the positive electrode material layer per unit area of the positive electrode, the pore volume V2 of the negative electrode material layer per unit area of the negative electrode, the pore volume V3 per unit area of the separator, and non-aqueous electrolysis The ratio [(V1 + V2 + V3) / V4] with the total volume V4 of the liquid storage element was 0.59.
The ratio (P1 / P2) between the porosity P1 of the positive electrode material layer and the porosity P2 of the separator was 0.50.
About the obtained non-aqueous electrolyte electrical storage element, it carried out similarly to Example 1, and performed the charging / discharging cycle. As a result, the capacity retention ratio after 50 cycles of Evaluation Method 1 obtained in the same manner as in Example 1 was 92.2%, and the capacity retention ratio after 50 cycles of Evaluation Method 2 was 79.3%. The results are shown in Table 2.

(Example 17)
Put the positive electrode H and the negative electrode I in a coin can, and add a non-aqueous electrolyte composed of a non-aqueous solvent (PC: DMC = 1: 1 (volume ratio)) in which 2 mol / L LiPF ₆ is dissolved, A separator having an average thickness of 60 μm and a porosity of 0.67 was inserted between the positive electrode and the negative electrode to assemble the nonaqueous electrolyte storage element of Example 17.
At this time, the pore volume V1 of the positive electrode material layer per unit area of the positive electrode, the pore volume V2 of the negative electrode material layer per unit area of the negative electrode, the pore volume V3 per unit area of the separator, and non-aqueous electrolysis The ratio [(V1 + V2 + V3) / V4] with the total volume V4 of the liquid storage element was 0.57.
The ratio (P1 / P2) between the porosity P1 of the positive electrode material layer and the porosity P2 of the separator was 0.25.
About the obtained non-aqueous electrolyte electrical storage element, it carried out similarly to Example 1, and performed the charging / discharging cycle. As a result, the capacity retention ratio after 50 cycles of Evaluation Method 1 obtained in the same manner as in Example 1 was 91.6%, and the capacity retention ratio after 50 cycles of Evaluation Method 2 was 84.4%. The results are shown in Table 2.

(Example 18)
Put the positive electrode I and the negative electrode I in a coin can, add a non-aqueous electrolyte composed of a non-aqueous solvent (PC: DMC = 1: 1 (volume ratio)) in which 2 mol / L LiPF ₆ is dissolved, A separator having an average thickness of 60 μm and a porosity of 0.67 was inserted between the positive electrode and the negative electrode to assemble the nonaqueous electrolyte storage element of Example 18.
At this time, the pore volume V1 of the positive electrode material layer per unit area of the positive electrode, the pore volume V2 of the negative electrode material layer per unit area of the negative electrode, the pore volume V3 per unit area of the separator, and non-aqueous electrolysis The ratio [(V1 + V2 + V3) / V4] to the total volume V4 of the liquid electricity storage element was 0.55.
The ratio (P1 / P2) between the porosity P1 of the positive electrode material layer and the porosity P2 of the separator was 0.14.
About the obtained non-aqueous electrolyte electrical storage element, it carried out similarly to Example 1, and performed the charging / discharging cycle. As a result, the capacity retention ratio after 50 cycles of Evaluation Method 1 obtained in the same manner as in Example 1 was 90.8%, and the capacity retention ratio after 50 cycles of Evaluation Method 2 was 85.3%. The results are shown in Table 2.

(Comparative Example 6)
Put the positive electrode F and the negative electrode G in a coin can, add a non-aqueous electrolyte composed of a non-aqueous solvent (PC: DMC = 1: 1 (volume ratio)) in which 2 mol / L LiPF ₆ is dissolved, A separator having a mean thickness of 100 μm and a porosity of 0.67 was inserted between the positive electrode and the negative electrode to assemble the nonaqueous electrolyte storage element of Comparative Example 6.
At this time, the pore volume V1 of the positive electrode material layer per unit area of the positive electrode, the pore volume V2 of the negative electrode material layer per unit area of the negative electrode, the pore volume V3 per unit area of the separator, and non-aqueous electrolysis The ratio [(V1 + V2 + V3) / V4] to the total volume V4 of the liquid storage element was 0.65.
The ratio (P1 / P2) between the porosity P1 of the positive electrode material layer and the porosity P2 of the separator was 0.36.
About the obtained non-aqueous electrolyte electrical storage element, it carried out similarly to Example 1, and performed the charging / discharging cycle. As a result, the capacity retention ratio after 50 cycles of Evaluation Method 1 obtained in the same manner as in Example 1 was 89.3%, and the capacity retention ratio after 50 cycles of Evaluation Method 2 was 68.9%. The results are shown in Table 2.

(Comparative Example 7)
Put the positive electrode G and the negative electrode F in a coin can, add a non-aqueous electrolyte composed of a non-aqueous solvent (PC: DMC = 1: 1 (volume ratio)) in which 2 mol / L LiPF ₆ is dissolved, A separator having a mean thickness of 100 μm and a porosity of 0.67 was inserted between the positive electrode and the negative electrode to assemble the nonaqueous electrolyte storage element of Comparative Example 7.
At this time, the pore volume V1 of the positive electrode material layer per unit area of the positive electrode, the pore volume V2 of the negative electrode material layer per unit area of the negative electrode, the pore volume V3 per unit area of the separator, and non-aqueous electrolysis The ratio [(V1 + V2 + V3) / V4] with the total volume V4 of the liquid storage element was 0.64.
The ratio (P1 / P2) between the porosity P1 of the positive electrode material layer and the porosity P2 of the separator was 0.25.
About the obtained non-aqueous electrolyte electrical storage element, it carried out similarly to Example 1, and performed the charging / discharging cycle. As a result, the capacity retention ratio after 50 cycles of Evaluation Method 1 obtained in the same manner as in Example 1 was 91.4%, and the capacity retention ratio after 50 cycles of Evaluation Method 2 was 69.2%. The results are shown in Table 2.

(Comparative Example 8)
Put the positive electrode J and the negative electrode I in a coin can, add a non-aqueous electrolyte composed of a non-aqueous solvent (PC: DMC = 1: 1 (volume ratio)) in which 2 mol / L LiPF ₆ is dissolved, A separator having an average thickness of 60 μm and a porosity of 0.67 was inserted between the positive electrode and the negative electrode to assemble the nonaqueous electrolyte storage element of Comparative Example 8.
At this time, the pore volume V1 of the positive electrode material layer per unit area of the positive electrode, the pore volume V2 of the negative electrode material layer per unit area of the negative electrode, the pore volume V3 per unit area of the separator, and non-aqueous electrolysis The ratio [(V1 + V2 + V3) / V4] to the total volume V4 of the liquid electricity storage element was 0.55.
The ratio (P1 / P2) between the porosity P1 of the positive electrode material layer and the porosity P2 of the separator was 0.11.
About the obtained non-aqueous electrolyte electrical storage element, it carried out similarly to Example 1, and performed the charging / discharging cycle. As a result, the capacity retention ratio after 50 cycles of Evaluation Method 1 obtained in the same manner as in Example 1 was 79.4%, and the capacity retention ratio after 50 cycles of Evaluation Method 2 was 68.7%. The results are shown in Table 2.

(Comparative Example 9)
Put the positive electrode J and the negative electrode J in a coin can, and add a non-aqueous electrolyte composed of a non-aqueous solvent (PC: DMC = 1: 1 (volume ratio)) in which 2 mol / L LiPF ₆ is dissolved, A separator having a mean thickness of 60 μm and a porosity of 0.67 was inserted between the positive electrode and the negative electrode to assemble the nonaqueous electrolyte storage element of Comparative Example 9.
At this time, the pore volume V1 of the positive electrode material layer per unit area of the positive electrode, the pore volume V2 of the negative electrode material layer per unit area of the negative electrode, the pore volume V3 per unit area of the separator, and non-aqueous electrolysis The ratio [(V1 + V2 + V3) / V4] with the total volume V4 of the liquid electricity storage element was 0.54.
The ratio (P1 / P2) between the porosity P1 of the positive electrode material layer and the porosity P2 of the separator was 0.11.
About the obtained non-aqueous electrolyte electrical storage element, it carried out similarly to Example 1, and performed the charging / discharging cycle. As a result, the capacity retention ratio after 50 cycles of Evaluation Method 1 obtained in the same manner as in Example 1 was 68.7%, and the capacity retention ratio after 50 cycles of Evaluation Method 2 was 58.3%. The results are shown in Table 2.

(Example 19)
Put the positive electrode G and the negative electrode B in a coin can, add a non-aqueous electrolyte composed of a non-aqueous solvent (PC: DMC = 1: 1 (volume ratio)) in which 2 mol / L LiPF ₆ is dissolved, A separator having an average thickness of 30 μm and a porosity of 0.67 was inserted between the positive electrode and the negative electrode to assemble the nonaqueous electrolyte storage element of Example 19.
At this time, the pore volume V1 of the positive electrode material layer per unit area of the positive electrode, the pore volume V2 of the negative electrode material layer per unit area of the negative electrode, the pore volume V3 per unit area of the separator, and non-aqueous electrolysis The ratio [(V1 + V2 + V3) / V4] with the total volume V4 of the liquid storage element was 0.58.
The ratio (P1 / P2) between the porosity P1 of the positive electrode material layer and the porosity P2 of the separator was 0.84.
About the obtained non-aqueous electrolyte electrical storage element, it carried out similarly to Example 1, and performed the charging / discharging cycle. As a result, the capacity retention ratio after 50 cycles of Evaluation Method 1 obtained in the same manner as in Example 1 was 93.4%, and the capacity retention ratio after 50 cycles of Evaluation Method 2 was 73.3%. The results are shown in Table 2.

(Example 20)
Put the positive electrode H and the negative electrode B in a coin can, add a non-aqueous electrolyte composed of a non-aqueous solvent (PC: DMC = 1: 1 (volume ratio)) in which 2 mol / L LiPF ₆ is dissolved, A separator having an average thickness of 30 μm and a porosity of 0.67 was inserted between the positive electrode and the negative electrode to assemble the nonaqueous electrolyte storage element of Example 20.
At this time, the pore volume V1 of the positive electrode material layer per unit area of the positive electrode, the pore volume V2 of the negative electrode material layer per unit area of the negative electrode, the pore volume V3 per unit area of the separator, and non-aqueous electrolysis The ratio [(V1 + V2 + V3) / V4] to the total volume V4 of the liquid electricity storage element was 0.55.
The ratio (P1 / P2) between the porosity P1 of the positive electrode material layer and the porosity P2 of the separator was 0.49.
About the obtained non-aqueous electrolyte electrical storage element, it carried out similarly to Example 1, and performed the charging / discharging cycle. As a result, the capacity retention ratio after 50 cycles of Evaluation Method 1 obtained in the same manner as in Example 1 was 92.6%, and the capacity retention ratio after 50 cycles of Evaluation Method 2 was 78.7%. The results are shown in Table 2.

(Example 21)
Put the positive electrode I and the negative electrode B in a coin can, add a non-aqueous electrolyte composed of a non-aqueous solvent (PC: DMC = 1: 1 (volume ratio)) in which 2 mol / L LiPF ₆ is dissolved, A separator having an average thickness of 30 μm and a porosity of 0.67 was inserted between the positive electrode and the negative electrode to assemble the nonaqueous electrolyte storage element of Example 21.
At this time, the pore volume V1 of the positive electrode material layer per unit area of the positive electrode, the pore volume V2 of the negative electrode material layer per unit area of the negative electrode, the pore volume V3 per unit area of the separator, and non-aqueous electrolysis The ratio [(V1 + V2 + V3) / V4] with the total volume V4 of the liquid storage element was 0.53.
The ratio (P1 / P2) between the porosity P1 of the positive electrode material layer and the porosity P2 of the separator was 0.27.
About the obtained non-aqueous electrolyte electrical storage element, it carried out similarly to Example 1, and performed the charging / discharging cycle. As a result, the capacity retention ratio after 50 cycles of Evaluation Method 1 obtained in the same manner as in Example 1 was 91.4%, and the capacity retention ratio after 50 cycles of Evaluation Method 2 was 83.7%. The results are shown in Table 2.

(Example 22)
Put the positive electrode G and the negative electrode C in a coin can, add a non-aqueous electrolyte composed of a non-aqueous solvent (PC: DMC = 1: 1 (volume ratio)) in which 2 mol / L LiPF ₆ is dissolved, A separator having an average thickness of 30 μm and a porosity of 0.67 was inserted between the positive electrode and the negative electrode to assemble the nonaqueous electrolyte storage element of Example 22.
At this time, the pore volume V1 of the positive electrode material layer per unit area of the positive electrode, the pore volume V2 of the negative electrode material layer per unit area of the negative electrode, the pore volume V3 per unit area of the separator, and non-aqueous electrolysis The ratio [(V1 + V2 + V3) / V4] to the total volume V4 of the liquid electricity storage element was 0.55.
The ratio (P1 / P2) between the porosity P1 of the positive electrode material layer and the porosity P2 of the separator was 0.84.
About the obtained non-aqueous electrolyte electrical storage element, it carried out similarly to Example 1, and performed the charging / discharging cycle. As a result, the capacity retention ratio after 50 cycles of Evaluation Method 1 obtained in the same manner as in Example 1 was 92.7%, and the capacity retention ratio after 50 cycles of Evaluation Method 2 was 75.8%. The results are shown in Table 2.

(Example 23)
Put the positive electrode H and the negative electrode C in a coin can, add a non-aqueous electrolyte composed of a non-aqueous solvent (PC: DMC = 1: 1 (volume ratio)) in which 2 mol / L LiPF ₆ is dissolved, A separator having an average thickness of 40 μm and a porosity of 0.67 was inserted between the positive electrode and the negative electrode to assemble the nonaqueous electrolyte storage element of Example 23.
At this time, the pore volume V1 of the positive electrode material layer per unit area of the positive electrode, the pore volume V2 of the negative electrode material layer per unit area of the negative electrode, the pore volume V3 per unit area of the separator, and non-aqueous electrolysis The ratio [(V1 + V2 + V3) / V4] with the total volume V4 of the liquid storage element was 0.53.
The ratio (P1 / P2) between the porosity P1 of the positive electrode material layer and the porosity P2 of the separator was 0.37.
About the obtained non-aqueous electrolyte electrical storage element, it carried out similarly to Example 1, and performed the charging / discharging cycle. As a result, the capacity retention ratio after 50 cycles of Evaluation Method 1 obtained in the same manner as in Example 1 was 91.3%, and the capacity retention ratio after 50 cycles of Evaluation Method 2 was 81.2%. The results are shown in Table 2.

(Example 24)
Put the positive electrode I and the negative electrode C in a coin can, and add a non-aqueous electrolyte composed of a non-aqueous solvent (PC: DMC = 1: 1 (volume ratio)) in which 2 mol / L LiPF ₆ is dissolved, A separator having an average thickness of 40 μm and a porosity of 0.67 was inserted between the positive electrode and the negative electrode to assemble the nonaqueous electrolyte storage element of Example 24.
At this time, the pore volume V1 of the positive electrode material layer per unit area of the positive electrode, the pore volume V2 of the negative electrode material layer per unit area of the negative electrode, the pore volume V3 per unit area of the separator, and non-aqueous electrolysis The ratio [(V1 + V2 + V3) / V4] to the total volume V4 of the liquid storage element was 0.52.
The ratio (P1 / P2) between the porosity P1 of the positive electrode material layer and the porosity P2 of the separator was 0.21.
About the obtained non-aqueous electrolyte electrical storage element, it carried out similarly to Example 1, and performed the charging / discharging cycle. As a result, the capacity retention ratio after 50 cycles of Evaluation Method 1 obtained in the same manner as in Example 1 was 91.7%, and the capacity retention ratio after 50 cycles of Evaluation Method 2 was 86.0%. The results are shown in Table 2.

(Example 25)
Put the positive electrode G and the negative electrode D in a coin can, add a non-aqueous electrolyte composed of a non-aqueous solvent (PC: DMC = 1: 1 (volume ratio)) in which 2 mol / L LiPF ₆ is dissolved, A separator having an average thickness of 30 μm and a porosity of 0.67 was inserted between the positive electrode and the negative electrode to assemble the nonaqueous electrolyte storage element of Example 25.
At this time, the pore volume V1 of the positive electrode material layer per unit area of the positive electrode, the pore volume V2 of the negative electrode material layer per unit area of the negative electrode, the pore volume V3 per unit area of the separator, and non-aqueous electrolysis The ratio [(V1 + V2 + V3) / V4] with the total volume V4 of the liquid storage element was 0.53.
The ratio (P1 / P2) between the porosity P1 of the positive electrode material layer and the porosity P2 of the separator was 0.84.
About the obtained non-aqueous electrolyte electrical storage element, it carried out similarly to Example 1, and performed the charging / discharging cycle. As a result, the capacity retention ratio after 50 cycles of Evaluation Method 1 obtained in the same manner as in Example 1 was 90.3%, and the capacity retention ratio after 50 cycles of Evaluation Method 2 was 78.3%. The results are shown in Table 2.

(Example 26)
Put the positive electrode H and the negative electrode D in a coin can, add a non-aqueous electrolyte composed of a non-aqueous solvent (PC: DMC = 1: 1 (volume ratio)) in which 2 mol / L LiPF ₆ is dissolved, A separator having an average thickness of 40 μm and a porosity of 0.67 was inserted between the positive electrode and the negative electrode to assemble the nonaqueous electrolyte storage element of Example 26.
At this time, the pore volume V1 of the positive electrode material layer per unit area of the positive electrode, the pore volume V2 of the negative electrode material layer per unit area of the negative electrode, the pore volume V3 per unit area of the separator, and non-aqueous electrolysis The ratio [(V1 + V2 + V3) / V4] with the total volume V4 of the liquid storage element was 0.51.
The ratio (P1 / P2) between the porosity P1 of the positive electrode material layer and the porosity P2 of the separator was 0.37.
About the obtained non-aqueous electrolyte electrical storage element, it carried out similarly to Example 1, and performed the charging / discharging cycle. As a result, the capacity retention ratio after 50 cycles of Evaluation Method 1 obtained in the same manner as in Example 1 was 91.1%, and the capacity retention ratio after 50 cycles of Evaluation Method 2 was 84.1%. The results are shown in Table 2.

(Example 27)
Put the positive electrode I and the negative electrode D in a coin can, add a non-aqueous electrolyte composed of a non-aqueous solvent (PC: DMC = 1: 1 (volume ratio)) in which 2 mol / L LiPF ₆ is dissolved, A non-aqueous electrolyte storage element of Example 27 was assembled by inserting a cellulose separator having an average thickness of 50 μm and a porosity of 0.67% between the positive electrode and the negative electrode.
At this time, the pore volume V1 of the positive electrode material layer per unit area of the positive electrode, the pore volume V2 of the negative electrode material layer per unit area of the negative electrode, the pore volume V3 per unit area of the separator, and non-aqueous electrolysis The ratio [(V1 + V2 + V3) / V4] with the total volume V4 of the liquid storage element was 0.51.
The ratio (P1 / P2) between the porosity P1 of the positive electrode material layer and the porosity P2 of the separator was 0.16.
About the obtained non-aqueous electrolyte electrical storage element, it carried out similarly to Example 1, and performed the charging / discharging cycle. As a result, the capacity retention ratio after 50 cycles of Evaluation Method 1 obtained in the same manner as in Example 1 was 90.8%, and the capacity retention ratio after 50 cycles of Evaluation Method 2 was 86.1%. The results are shown in Table 2.

  In the following Tables 1-1 to 1-3, the conditions of the nonaqueous electrolyte storage elements of Examples 1 to 27 and Comparative Examples 1 to 9 are collectively shown.

In Example 1-27, the capacity of the positive electrode, 1 mg / cm ² per ^{was 0.05mAh / cm 2 ~0.06mAh / cm 2} . Since the area density of the positive electrode is ^{3mg / cm 2 ~10mg / cm 2} , the anion adsorption emission amount per unit area of the positive electrode was ^{0.15mAh / cm 2 ~0.60mAh / cm 2} .

In Examples 1 to 27, the capacity of the negative electrode was 0.170 mAh / cm ² per 1 mg / cm ² . As described above, the capacity of the positive electrode, 1 mg / cm ² per ^{a 0.05mAh / cm 2 ~0.06mAh / cm 2} , the capacity per unit area of the negative electrode, than the capacitance per unit area of the positive electrode It was big.
Wherein a capacitance C1 per unit area of the negative electrode, wherein the capacitance C2 per unit area of the positive electrode, the capacitance ratio ^{(C1 / C2) = 0.170mAh /} cm 2 /0.05mAh/cm 2 ~0.170mAh / cm ^{2 /} 0.06 mAh / cm ² = 3.4 to 2.8.

Aspects of the present invention are as follows, for example.
<1> A positive electrode including a positive electrode material layer containing a positive electrode active material capable of reversibly accumulating or releasing anions, and a negative electrode including a negative electrode material layer containing a negative electrode active material capable of reversibly accumulating or releasing cations. A non-aqueous electrolyte storage element having a separator and a non-aqueous electrolyte containing an electrolyte salt between the positive electrode and the negative electrode,
The pore volume V1 of the positive electrode material layer per unit area of the positive electrode, the pore volume V2 of the negative electrode material layer per unit area of the negative electrode, the pore volume V3 per unit area of the separator, and the nonaqueous electrolyte storage element Satisfying the following formula, 0.5 ≦ [(V1 + V2 + V3) / V4] ≦ 0.61,
The non-aqueous electrolyte storage element is characterized in that the porosity P1 of the positive electrode material layer and the porosity P2 of the separator satisfy the following formula: 0.14 ≦ P1 / P2 ≦ 0.84.
<2> The nonaqueous electrolyte storage element according to <1>, wherein a porosity P1 of the positive electrode material layer and a porosity of the negative electrode material layer are both 0.25 or more and 0.65 or less.
<3> The nonaqueous electrolytic solution according to any one of <1> to <2>, wherein the amount of anion storage / release per unit area of the positive electrode is 0.15 mAh / cm ² or more and 0.60 mAh / cm ² or less. It is a power storage element.
<4> The nonaqueous electrolyte storage element according to any one of <1> to <3>, wherein a capacity per unit area of the negative electrode is larger than a capacity per unit area of the positive electrode.
<5> The capacity C1 per unit area of the negative electrode and the capacity C2 per unit area of the positive electrode are such that the capacity ratio (C1 / C2) is 1.05 or more and 6 or less. It is a water electrolyte storage element.
<6> The nonaqueous electrolyte storage element according to any one of <1> to <5>, wherein the electrolyte salt is a lithium salt.
<7> The nonaqueous electrolyte storage element according to any one of <1> to <6>, wherein a content of the electrolyte salt in the nonaqueous electrolyte is 1.5 mol / L or more and 3.0 mol / L or less. It is.
<8> The nonaqueous electrolyte storage element according to any one of <1> to <7>, wherein the positive electrode active material is a carbonaceous material.
<9> The nonaqueous electrolyte storage element according to any one of <1> to <8>, wherein the negative electrode active material is any one of a carbonaceous material and lithium titanate.
<10> The nonaqueous electrolyte storage element according to any one of <1> to <9>, wherein the separator has an average thickness of 20 μm to 200 μm.

  According to the non-aqueous electrolyte storage element according to any one of <1> to <10>, the conventional problems can be solved and the object of the present invention can be achieved.

DESCRIPTION OF SYMBOLS 1 Positive electrode 2 Negative electrode 3 Separator 4 Exterior can 5 Negative electrode lead wire 6 Positive electrode lead wire 10 Nonaqueous electrolyte storage element

JP 2014-130717 A

Journal of The Electrochemical Society, 147 (3) 899-901 (2000)

Claims (10)

A positive electrode including a positive electrode material layer containing a positive electrode active material capable of reversibly accumulating or releasing anions, a negative electrode including a negative electrode material layer containing a negative electrode active material capable of reversibly accumulating or releasing cations, and the positive electrode A non-aqueous electrolyte storage element having a separator and a non-aqueous electrolyte containing an electrolyte salt between the negative electrode and the negative electrode,
The pore volume V1 of the positive electrode material layer per unit area of the positive electrode, the pore volume V2 of the negative electrode material layer per unit area of the negative electrode, the pore volume V3 per unit area of the separator, and the nonaqueous electrolyte storage element Satisfying the following formula, 0.5 ≦ [(V1 + V2 + V3) / V4] ≦ 0.61,
The non-aqueous electrolyte storage element, wherein the porosity P1 of the positive electrode material layer and the porosity P2 of the separator satisfy the following formula: 0.14 ≦ P1 / P2 ≦ 0.84.   2. The nonaqueous electrolyte storage element according to claim 1, wherein a porosity P1 of the positive electrode material layer and a porosity of the negative electrode material layer are both 0.25 or more and 0.65 or less. 3. The non-aqueous electrolyte storage element according to claim 1, wherein an anion storage / release amount per unit area of the positive electrode is 0.15 mAh / cm ² or more and 0.60 mAh / cm ² or less.   4. The nonaqueous electrolyte storage element according to claim 1, wherein a capacity per unit area of the negative electrode is larger than a capacity per unit area of the positive electrode.   5. The nonaqueous electrolyte storage according to claim 4, wherein a capacity C1 per unit area of the negative electrode and a capacity C2 per unit area of the positive electrode are a capacity ratio (C1 / C2) = 1.05 or more and 6 or less. element.   The non-aqueous electrolyte storage element according to claim 1, wherein the electrolyte salt is a lithium salt.   7. The non-aqueous electrolyte storage element according to claim 1, wherein the content of the electrolyte salt in the non-aqueous electrolyte is 1.5 mol / L or more and 3.0 mol / L or less.   The non-aqueous electrolyte storage element according to claim 1, wherein the positive electrode active material is a carbonaceous material.   The non-aqueous electrolyte storage element according to any one of claims 1 to 8, wherein the negative electrode active material is any one of a carbonaceous material and lithium titanate.   The non-aqueous electrolyte storage element according to claim 1, wherein an average thickness of the separator is 20 μm or more and 200 μm or less.