JP3247103B1 - Organic electrolyte secondary battery - Google Patents

Abstract

An organic electrolyte secondary battery having excellent safety is provided. A positive electrode, (002) plane anode and chain ester interlayer distance d ₀₀₂ is using the following carbon materials 0.35 nm, and partially coating the surface by reacting with the organic electrolyte solution is formed of In the organic electrolyte secondary battery having an organic electrolyte having a main solvent of, a non-ionic selected from the group consisting of trimellitic acid ester or a derivative thereof, tertiary butylbenzene, isobutylbenzene, and cyclohexylbenzene in the organic electrolyte. An ionic aromatic compound is contained.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

The present invention relates to an organic electrolyte secondary battery, and more particularly, to an organic electrolyte secondary battery having excellent safety.

[0002]

2. Description of the Related Art An organic electrolyte secondary battery is a secondary battery using an organic solvent as a solvent of the electrolyte. The organic electrolyte secondary battery has a large capacity, a high voltage, a high energy density, and a high capacity. Because of the output, the demand tends to increase more and more.

[0003] As a solvent for an organic electrolytic solution of this battery (hereinafter simply referred to as "electrolyte solution" except when the battery is referred to), cyclic esters such as ethylene carbonate and dimethyl carbonate, diethyl carbonate, propionate have been used. It has been used in combination with a chain ester such as methyl acid.

However, as this organic electrolyte secondary battery has been studied for the purpose of further improving its safety,
If a chain ester is used as the main solvent as the solvent for the electrolyte, or if the negative electrode has a large chargeable / dischargeable capacity, the internal structure of the battery may cause an internal short circuit or It was found that the safety in the case of stabbing tended to decrease.

[0005] Usually, measures are taken to prevent overcharging by a protection circuit or the like so as not to cause an internal short circuit, and a normal internal short circuit does not cause an abnormal situation because the battery only generates heat. In addition, nail penetration rarely occurs and is unlikely to occur unless the user intentionally performs it. As a possibility, it is assumed that the battery is partially crushed due to an impact accident or the like.

For this purpose, a crush test of the battery is performed, but it is usually safe. However, it is difficult to say that it is safe enough to test only a few dozen, but it is desirable to confirm the safety by conducting a test under more dangerous conditions.

[0007] On the other hand, in the nail penetration test, the battery is reliably short-circuited in a smaller portion than the battery crush test. Easy to be. For this reason, variations in the fuses (clogging due to melting) of the separator are likely to occur, and the heat generated by the reaction between the electrolyte and the negative electrode at the short-circuited portion increases. Therefore, the nail penetration test is effective as a severe safety test. Further, when the nail penetration test is performed at a high temperature of 40 ° C. than at room temperature, the battery easily rises to a higher temperature, and the thermal runaway reaction of the battery is more likely to occur. Further, when the nail is stopped in the middle of the battery as in the case of a 釘 nail penetration, the short-circuit portion is reduced, and the current is more concentrated and heat is easily generated. Therefore,
To obtain higher safety, 1/1
(2) It is desirable to be able to withstand the nail penetration test to some extent.

[0008]

By the way, (002)
When a carbon material having a surface interlayer distance d ₀₀₂ of 0.35 nm or less is used for the negative electrode, the reactivity with the electrolytic solution at a high temperature is much lower than when lithium metal is used, and the safety of the battery is improved. You. In order to improve the safety, it is indispensable to have a good quality film formed by reacting with the electrolytic solution on the surface of the negative electrode using the carbon material.

Regarding the reaction with the electrolyte on the surface of the negative electrode, see D. Aurbach et al. Report that organic carbonates (ROCO ₂ Li), Li ₂ CO ₃ , alkoxides (ROLi) and the like are formed on carbon [J. Electrochemical Soc. , V
ol142 (No. 9), p2882 (1995)].
In the same report, in a mixed solvent of cyclic ester ethylene carbonate and chain ester diethyl carbonate, the ratio of chain ester diethyl carbonate to cyclic ester ethylene carbonate is 1: 1.
It is reported that higher levels have an adverse effect on cycling characteristics. Further, in the study of the present inventors, particularly, when the ratio of a chain ester such as diethyl carbonate increases, especially when the ratio of a chain ester having a methyl group increases, safety in short circuiting and nail penetration decreases. I have found a tendency.

Accordingly, an object of the present invention is to solve the problems related to the safety of the conventional organic electrolyte secondary battery and to provide an organic electrolyte secondary battery having excellent safety.

[0011]

The present invention provides a positive electrode, (00
2) Use a carbon material having a surface interlayer distance d ₀₀₂ of 0.35 nm or less, and use a negative electrode having a film formed on the surface by partially reacting with the electrolytic solution and an electrolytic solution containing a chain ester as a main solvent. in the organic electrolyte secondary battery comprising, the electrolytic trimellitic acid ester or its derivative in liquid, tertiary or isobutyl benzene _{(C 6 H 5 -C 4 H} 9) and cyclohexylbenzene _{(C 6 H 11 -C 6 H} 5 The above problem has been solved by adding a nonionic aromatic compound selected from the group consisting of (i) and (ii).

[0012]

BEST MODE FOR CARRYING OUT THE INVENTION As the above trimellitic acid ester or a derivative thereof, for example, tri-2-ethylhexyl trimellitate [(C ₆ H ₃ (COOC ₈ H ₁₇ )]
₃ ].

The alkyl group of the nonionic aromatic compound used in the present invention preferably has 2 or more carbon atoms, more preferably has 4 or more carbon atoms, and still more preferably has 5 carbon atoms. That is all. The alkyl group may be directly bonded to the benzene ring,
More preferably, it is bonded to the benzene ring via an OO group. That is, the longer the alkyl group and the presence of the COO group, the greater the barrier effect on the negative electrode surface (the effect of suppressing a rapid reaction between the electrode and the electrolyte at a high temperature).
Here, non-ionic in the non-ionic aromatic compound means that the compound does not have a cation part or an anion part in a molecule.

In the present invention, the content of the nonionic aromatic compound having the specific alkyl group in the electrolytic solution is preferably 0.1 part by volume or more based on 100 parts by volume of the electrolytic solution solvent. , 0.2 volume parts or more, and most preferably 0.5 volume parts or more. When the nonionic aromatic compound having the specific alkyl group is a solid, a value obtained by converting the density into a volume is used. The content of the nonionic aromatic compound having the specific alkyl group in the electrolytic solution is preferably 10 parts by volume or less, more preferably 2 parts by volume or less, with respect to 100 parts by volume of the electrolytic solution solvent. The capacity part or less is most desirable.

If the content of the nonionic aromatic compound having the specific alkyl group in the electrolyte is smaller than the above, the safety cannot be sufficiently improved, and the specific alkyl group cannot be used. If the content of the nonionic aromatic compound in the electrolyte is higher than the above, the cycle characteristics and load characteristics of the battery may be deteriorated.

The present inventors have studied in detail the effect of adding an aromatic compound to an electrolytic solution on the safety of a battery. To explain this in detail, the present inventors first performed a nail penetration test of a lithium ion battery assuming an internal short circuit or the like. It was found that the risk increased as the density increased.

For the negative electrode of these batteries, a compound such as a carbon material which can insert and remove lithium is usually used.
If the negative electrode is overcharged and some lithium is electrodeposited, about 1
From around 00 ° C., an exothermic reaction occurs between the electrolytic solution and electrodeposited lithium or a carbon material into which lithium is inserted. On the other hand, when the lithium is desorbed from the positive electrode, the temperature at which the reaction with the electrolyte solution starts decreases, and when the temperature rises to the thermal runaway temperature of the positive electrode due to the heat of reaction of the negative electrode, the battery generates abnormal heat.

Due to such a heat generation phenomenon accompanied by a continuous reaction, if the chargeable / dischargeable capacity of the negative electrode of the battery under normal use conditions exceeds 85 mAh / cm ³ per unit volume of the battery, the battery becomes excessive. Safety when charged is reduced. In other words, the greater the dischargeable capacity per unit volume of the negative electrode, the greater the amount of heat generated per unit volume of the battery if heat is generated during overcharge, and the higher the possibility that the battery temperature will rise to the thermal runaway temperature of the positive electrode. It becomes. Therefore, it is necessary to suppress the exothermic reaction between the negative electrode and the electrolytic solution as the battery has a larger negative electrode capacity per unit volume. Further, since the calorific value increases even when the battery size is large, it is necessary to suppress the exothermic reaction between the negative electrode and the electrolytic solution, and the effect of the present invention containing the nonionic aromatic compound having the above specific alkyl group is contained. Is remarkably expressed. The size of the cell is 10 cm ³ or more,
In particular, when it is 15 cm ³ or more, the effect of the present invention is more remarkably exhibited.

In order to improve the safety of the battery, it is known to add a nonflammable solvent to the electrolyte solution, dissolve the polymer, or add an aromatic compound. By using a nonionic aromatic compound having an alkyl group in a battery having a chain ester as a main solvent,
It has been found that the present invention has a particularly excellent effect in improving safety.
In the present invention, the reason why the safety can be improved by adding the nonionic aromatic compound having the specific alkyl group described above is considered as follows.

The interlayer distance d ₀₀₂ of the (002) plane is 0.35
By producing a negative electrode using a carbon material of nm or less, the reactivity of the electrolyte and the negative electrode at a high temperature is suppressed as compared with the case of using lithium, but the chargeable / dischargeable capacity of the negative electrode increases. As a result, the reactivity with the electrolytic solution increases, the amount of heat generated when the battery generates heat and the reaction between the negative electrode and the electrolytic solution occurs increases, and the temperature easily rises. However, when the aromatic compound is added to the electrolyte, the aromatic compound is adsorbed on the surface of the negative electrode and suppresses the direct contact between the surface of the negative electrode and the chain ester. It is believed that the reactivity is reduced and the temperature rise is limited. It was also found that the aromatic compound having a specific alkyl group was more effective. The details will be clarified in Examples described later.

The chain ester used as the main solvent of the electrolytic solution is, for example, an organic solvent having a chain COO-bond, such as dimethyl carbonate, diethyl carbonate, methyl ethyl carbonate, methyl propionate and the like.
The main solvent means that the chain ester exceeds 50% by volume in the total electrolyte solvent containing these chain esters. If the chain ester exceeds 65% by volume, the safety of the battery in the nail penetration test tends to decrease, and the effect of adding the nonionic aromatic compound having a specific alkyl group increases. When the amount of the chain ester exceeds 70% by volume, the effect of adding the nonionic aromatic compound having a specific alkyl group is further increased, and the amount of the chain ester becomes 75%.
When the content is more than the volume%, the effect of adding the nonionic aromatic compound having a specific alkyl group is further increased. Also, when the chain ester has a methyl group, the safety of the battery is likely to be reduced, so that the effect of adding the nonionic aromatic compound having a specific alkyl group becomes more remarkable.

When the following ester having a high dielectric constant (dielectric constant of 30 or more) is mixed with the above-mentioned chain ester and used,
Since the cycle characteristics and the load characteristics of the battery are improved as compared with the case where only the chain ester is used, the battery is more desirable. Examples of such an ester having a high dielectric constant include propylene carbonate (PC), ethylene carbonate (EC), butylene carbonate (BC), gamma-butyrolactone (γ-BL), and ethylene glycol sulfite (EGS). In particular, those having a cyclic structure are preferred, and cyclic carbonates are particularly preferred. Ethylene carbonate (EC)
Is most preferred.

The ester having a high dielectric constant is preferably less than 40% by volume, more preferably 30% by volume, of the total solvent of the electrolytic solution.
% By volume or less, more preferably 25% by volume or less.
The improvement of the safety by these esters having a high dielectric constant becomes remarkable when the ester having a high dielectric constant becomes 10% by volume or more in the entire solvent of the electrolytic solution, and becomes further remarkable when it reaches 20% by volume. .

Examples of the solvent which can be used in combination with a chain ester other than the ester having a high dielectric constant include 1,2-dimethoxyethane (DME), 1,3-dioxolane (D
O), tetrahydrofuran (THF), 2-methyl-tetrahydrofuran (2Me-THF), diethyl ether (DEE) and the like. In addition, an amine imide-based organic solvent, a sulfur-containing or fluorine-containing organic solvent, and the like can also be used.

As an electrolyte of the electrolytic solution, for example, LiC
10_Four, LiPF₆, LiBF_Four, LiAsF₆, Li
SbF₆, LiCF_ThreeSO_Three, LiC_FourF₉SO_Three, L
iCF_ThreeCO_Two, Li_TwoC_TwoF_Four(SO_Three)_Two, LiN
(CF_ThreeSO_Two)_Two, LiC (CF_ThreeSO_Two)_Three, Li
C_nF_{2n + 1}SO_Three(N ≧ 2), LiN (Rf_ThreeOS
O _Two)_Two[Where Rf is a fluoroalkyl group]
Used alone or as a mixture of two or more, especially LiP
F₆And LiC_FourF₉SO_ThreeHave good charge / discharge characteristics
And desirable. The concentration of the electrolyte in the electrolyte is
The concentration is not limited to 1 mol / l or more
It is desirable to improve the safety, 1.2 mol
/ L or more is more desirable. In addition, the voltage in the electrolyte
Good electricity when the concentration of the decomposition is 1.7 mol / l or less
Desirable because characteristics are maintained, and 1.5 mol / l or less
It is even more desirable.

As the positive electrode active material, for example, LiCoO
Lithium cobalt oxides such as _2, lithium manganese oxide such as LiMn ₂ O _4, lithium nickel oxides such as LiNiO _2, manganese dioxide, vanadium pentoxide, chromium oxide, a metal oxide or titanium disulfide, such as a two A metal sulfide such as molybdenum sulfide is used.

For the positive electrode, for example, a mixture obtained by appropriately adding a conductive additive or a binder such as polyvinylidene fluoride to the positive electrode active material is formed into a molded body using a current collector material such as an aluminum foil as a core material. Finished products are used.

In particular, LiNiO ₂ , LiCoO ₂ , LiM
It is desirable to use a lithium composite oxide such as n ₂ O _{4 having} an open circuit voltage of 4 V or more on the Li basis as a positive electrode active material, since a high energy density can be obtained. In particular, the charged LiCoO ₂ or LiNiO ₂ has a lower reaction initiation temperature with the electrolytic solution than LiMn ₂ O ₄ and easily reaches the thermal runaway temperature of the positive electrode due to heat generation of the negative electrode, so that the effect of the present invention is more remarkably exhibited. .

The interlayer distance d of the (002) plane used for the negative electrode
Examples of the carbon material having ₀₀₂ of 0.35 nm or less include graphite, pyrolytic carbons, cokes, glassy carbons, fired bodies of organic polymer compounds, mesocarbon microbeads, carbon fibers, activated carbon, and the like. be able to.

The carbon material used for the negative electrode preferably has the following characteristics. That is, the interlayer distance d ₀₀₂ of the (002) plane is preferably 0.345 nm or less, more preferably 0.34 nm or less. Also,
The crystallite size Lc in the c-axis direction is desirably 3.0 nm or more, more desirably 8.0 nm or more, and further desirably 25.0 nm or more. The average particle size is desirably 8 to 15 μm, particularly desirably 10 to 13 μm, and the purity is desirably 99.9% or more.

[0031]

Next, the present invention will be described more specifically with reference to examples. However, the present invention is not limited to only these examples.

Example 1 Methyl ethyl carbonate and ethylene carbonate were mixed at a volume ratio of 76:24, and tri-2-ethylhexyl trimellitate [(C ₆ H ₃ (COOC ₈ H) was added to 100 parts by volume of the mixed solvent. ₁₇ ) ₃ ;
M ") was added and mixed, and LiPF ₆ was dissolved at 1.4 mol / l to give a composition of 1.4 mol / l.
LiPF ₆ / EC: MEC (24:76 volume ratio) +1
An electrolytic solution represented by% TOTM was prepared.

EC in the above electrolyte is an abbreviation for ethylene carbonate, and MEC is an abbreviation for methyl ethyl carbonate. Therefore, the above-mentioned electrolyte solution of 1.4mo
1 / l LiPF ₆ / EC: MEC (24:76 volume ratio) + 1% TOTM is methyl ethyl carbonate 76
It shows that 1.4 mol / l of LiPF ₆ was dissolved in a mixed solvent of 20% by volume of ethylene carbonate and 24% by volume of ethylene carbonate, and 1 part by volume of TOTM was dissolved in 100 parts by volume of the mixed solvent. .

Separately, LiC as a positive electrode active material
Phosphorous graphite is added to oO ₂ as a conductive additive in a weight ratio of 100: 7.
The mixture was mixed with a solution prepared by dissolving polyvinylidene fluoride in N-methylpyrrolidone to form a slurry. After passing the positive electrode mixture slurry through a 70-mesh net to remove a large one,
The positive electrode current collector made of a μm aluminum foil was uniformly applied to both sides and dried, then compression-molded by a roller press, cut, and then welded to a lead body to produce a belt-shaped positive electrode.

Next, a graphite-based carbon material (interlayer distance d ₀₀₂ = 0.337 nm, crystallite size L in the c-axis direction)
c = 95.0 nm, average particle diameter 10 μm, purity 99.9%
90 parts by weight of a graphite-based carbon material having the characteristic described above) were mixed with a solution of 10 parts by weight of vinylidene fluoride dissolved in N-methylpyrrolidone to form a slurry. The negative electrode mixture slurry was passed through a 70-mesh net to remove large particles, and then uniformly applied to both surfaces of a negative electrode current collector made of a strip-shaped copper foil having a thickness of 10 μm, dried, and then rolled. After compression molding with a press machine and cutting, the lead body was welded to produce a strip-shaped negative electrode.

The strip-shaped positive electrode is overlaid on the strip-shaped negative electrode via a microporous polyethylene film having a thickness of 25 μm, spirally wound into a spiral electrode body, and a cylindrical battery case with a bottom having an outer diameter of 18 mm. And the lead bodies of the positive electrode and the negative electrode were welded. Here, the positive electrode of the active material-containing mixture per unit volume of the opposed parts of the positive electrode and the negative electrode /
The negative electrode weight ratio was 2.06. The charge and discharge capacity of the negative electrode is
The battery was charged under normal charging conditions (charged at 1400 mA;
After reaching 1 V, the charging operation at a constant voltage of 4.1 V
(Performed for 30 minutes), the value was 85 mAh / cm ³ .

Next, the electrolytic solution was poured into the battery case, and after the electrolytic solution had sufficiently penetrated into the separator and the like, sealing was performed, preliminary charging and aging were performed, and a cylindrical organic electrolytic solution having the structure shown in FIG. A secondary battery was manufactured.

The battery shown in FIG. 1 will be described briefly. 1 is the positive electrode and 2 is the negative electrode. However, FIG. 1 does not show the current collectors used for producing the positive electrode 1 and the negative electrode 2 in order to avoid complication, and the positive electrode 1 and the negative electrode 2 are spirally interposed through the separator 3. Wound, as a spiral electrode body, together with the electrolyte,
It is housed in a battery case 4 made of stainless steel.

The electrolyte contains TOTM (that is, tri-2-ethylhexyl trimellitate) as described above, and the battery case 4 also serves as a negative electrode terminal, and an insulator 5 Are arranged, and the insulator 6 is also arranged on the spiral electrode body. A sealing body 8 is arranged at the opening of the battery case 4 via an annular insulating packing 7, and the inside of the battery is sealed by tightening the opening end of the battery case 4 inward. However, a reversible vent mechanism for preventing the gas generated inside the battery from being ruptured under a high pressure by discharging the gas generated inside the battery to a certain pressure when the gas is raised to a certain pressure and preventing the battery from being ruptured under a high pressure. Have been.

Comparative Example 1 Instead of TOTM, dibutyl phthalate [C ₆ H ₄ (CO
A cylindrical organic electrolyte secondary battery was fabricated in the same manner as in Example 1 except that OC ₄ H ₉ ) ₂ ] was used.

Comparative Example 2 Dimethyl phthalate [C ₆ H ₄ (CO
A cylindrical organic electrolyte secondary battery was manufactured in the same manner as in Example 1 except that OCH ₃ ) ₂ ] was used.

Comparative Example 3 A cylindrical organic electrolyte secondary battery was manufactured in the same manner as in Example 1 except that toluene was used instead of TOTM.

Comparative Example 4 A cylindrical organic electrolyte secondary battery was produced in the same manner as in Example 1 except that the electrolyte did not contain a nonionic aromatic compound having an alkyl group.

Comparative Example 5 A cylindrical organic electrolyte secondary battery was prepared in the same manner as in Comparative Example 4, except that the volume ratio of ethylene carbonate (EC) to methyl ethyl carbonate (MEC) was 1: 2. Produced.

Comparative Example 6 A cylindrical organic electrolyte secondary battery was prepared in the same manner as in Comparative Example 4, except that the ratio of ethylene carbonate (EC) to methyl ethyl carbonate (MEC) was 1: 1 by volume. Produced.

COMPARATIVE EXAMPLE 7 An electrode having a positive electrode / negative electrode weight ratio of the active material-containing mixture per unit volume of 1.95 per unit volume of the positive electrode and the negative electrode at the time of electrode preparation was 1.95. Total thickness,
A cylindrical organic electrolyte secondary battery was produced in the same manner as in Comparative Example 6, except that a spirally wound electrode body was made to have the same winding diameter and a charge / discharge capacity of the negative electrode was made 1300 mAh. The chargeable / dischargeable capacity of the negative electrode was 79 mAh / cm ³ .

After discharging the batteries of Example 1 and Comparative Examples 1 to 7 to 2.75 V at 1400 mA,
After the battery was charged at 4.18 V and charged at 4.18 V, the battery was charged for 2 hours and 30 minutes under the condition of maintaining a constant voltage of 4.18 V. Thereafter, the battery was placed in a constant temperature bath at 40 ° C., taken out 2 hours later, placed on a wooden and grooved battery holder, and a stainless steel nail having a shaft diameter of 3 mm was perpendicular to the center of the side of the battery. Immediately, the battery was stabbed to a depth of の of the outer diameter of the battery to check for abnormal heat generation. Table 1 shows the results.

In this test, 20 batteries were used for each of the batteries of Example 1 and Comparative Examples 1 to 7. Table 1 shows the number of batteries used for the test in the denominator, and the number of batteries that generated abnormal heat in the numerator. The ratio of abnormal heat generation is shown in the form shown. 1/2 at 40 ° C above
The nail penetration test is a test under extremely severe conditions to confirm safety.

[0049]

[Table 1]

As shown in Table 1, in Example 1, the chain ester exceeded 50% by volume and constituted the main solvent of the electrolytic solution. However, no abnormal heat generation occurred, and the nonionic aromatic compound was used. Comparative Example 4 not containing, or a nonionic aromatic compound different from a nonionic aromatic compound selected from the group consisting of trimellitic acid ester or a derivative thereof, tertiary butylbenzene, isobutylbenzene and cyclohexylbenzene, It can be seen that the safety in the nail penetration test is improved as compared with Comparative Examples 1 to 3 in which the steel was contained. Further, when the chain ester such as methyl ethyl carbonate is small as in Comparative Examples 5 to 6, or when the chain ester has only an ethyl group, the rate of abnormal heat generation is low, and the above-mentioned specific alkyl group is contained. The effect of adding a nonionic aromatic compound tends to decrease. Furthermore, even when the charge / discharge capacity of the negative electrode is small as in Comparative Example 7, the rate of abnormal heat generation is small, and it can be seen that the effect of the addition of the nonionic aromatic compound having the specific alkyl group is small.

[0051]

As described above, according to the present invention, the carbon material having the positive electrode and the interlayer distance d ₀₀₂ of the (002) plane of 0.35 nm or less is used, and a part of the carbon material reacts with the organic electrolyte to form a surface. In an organic electrolyte secondary battery having an anode having a film formed thereon and an organic electrolyte having a chain ester as a main solvent, the organic electrolyte may be a trimellitic acid ester or a derivative thereof, tertiary butylbenzene, isobutylbenzene. By adding a nonionic aromatic compound selected from the group consisting of cyclohexylbenzene and cyclohexylbenzene, the safety of the battery could be improved. Particularly, the chargeable / dischargeable capacity of the negative electrode is 85 mAh per unit volume of the battery.
/ Cm ³ , the effect of improving safety is great.

[Brief description of the drawings]

FIG. 1 is a partial sectional perspective view schematically showing an example of an organic electrolyte secondary battery according to the present invention.

[Explanation of symbols]

 1 positive electrode 2 negative electrode 3 separator

────────────────────────────────────────────────── ─── Continuation of the front page (56) References JP-A-7-22069 (JP, A) (58) Field surveyed (Int. Cl. ⁷ , DB name) H01M 10/40

Claims (2)

(57) [Claims] 1. A positive electrode, a carbon material having an interlayer distance d ₀₀₂ of (002) plane of 0.35 nm or less, and a part of which reacts with an organic electrolytic solution to form a film on the surface and a chain. An organic electrolyte secondary battery having an organic electrolyte containing an ester as a main solvent, wherein the organic electrolyte is selected from the group consisting of trimellitate or a derivative thereof, tertiary butylbenzene, isobutylbenzene, and cyclohexylbenzene. An organic electrolyte secondary battery comprising a nonionic aromatic compound to be used. 2. The organic electrolyte secondary battery according to claim 1, wherein a chain ester having a methyl group is used as a solvent of the organic electrolyte.