WO2006018989A1

WO2006018989A1 - Additive for electrolyte solution of nonaqueous electrolyte battery, nonaqueous electrolyte solution for battery and nonaqueous electrolyte battery

Info

Publication number: WO2006018989A1
Application number: PCT/JP2005/014407
Authority: WO
Inventors: Masashi Otsuki
Original assignee: Bridgestone Corporation
Priority date: 2004-08-20
Filing date: 2005-08-05
Publication date: 2006-02-23
Also published as: JP2006059682A

Abstract

Disclosed is an additive for electrolyte solutions of nonaqueous electrolyte batteries which enables to raise the thermal runaway temperature of a nonaqueous electrolyte battery by a greater degree than the conventional additives for electrolyte solutions. Specifically disclosed is an additive for electrolyte solutions of nonaqueous electrolyte batteries which is composed of a phosphazene compound represented by the following formula (I): (NPX2)n (wherein Xs independently represent F or Cl, but not all Xs are the same; and n is 3 or 4) with the number of Cl bonded to each P being 0 or 1.

Description

Specification

Nonaqueous Electrolyte Battery Electrolyte Additive, Battery Nonaqueous Electrolyte, and Nonaqueous Electrolyte Battery

Technical field

TECHNICAL FIELD [0001] The present invention relates to an electrolyte additive for a non-aqueous electrolyte battery, a battery non-aqueous electrolyte containing the additive, and a non-aqueous electrolyte battery including the non-aqueous electrolyte, and in particular, a thermal runaway start temperature. The present invention relates to a non-aqueous electrolyte battery with improved performance.

Background art

[0002] In recent years, there has been a demand for a light, long-life battery with high energy density as a main power source or auxiliary power source for electric vehicles and fuel cell vehicles, or as a power source for small electronic devices. In contrast, a non-aqueous electrolyte battery using lithium as a negative electrode active material is known as one of the batteries having a high energy density because the electrode potential of lithium is the lowest among metals and the electric capacity per unit volume is large. Many types of batteries, whether primary batteries or secondary batteries, have been actively researched, and some have been put into practical use and supplied to the market. For example, non-aqueous electrolyte primary batteries are used as power sources for cameras, electronic watches, and various memory backups. In addition, non-aqueous electrolyte secondary batteries are used as drive power sources for notebook computers and mobile phones, and are also being considered for use as main power sources or auxiliary power sources for electric vehicles and fuel cell vehicles. Yes.

[0003] In these non-aqueous electrolyte batteries, the negative electrode active material lithium reacts violently with a compound having active protons such as water and alcohol, so that the electrolyte used in the battery is an ester compound or an ether compound. Limited to aprotic organic solvents such as

[0004] However, although the aprotic organic solvent has low reactivity with the negative electrode active material lithium, for example, a large current suddenly flows when the battery is short-circuited, and the battery abnormally generates heat. There is a high risk of vaporization 'decomposing to generate gas, rupture of the battery due to the generated gas and heat, and ignition of sparks generated at the time of short circuit.

[0005] On the other hand, a phosphazene compound is added to the battery non-aqueous electrolyte to obtain a non-aqueous electrolyte. Non-aqueous electrolyte batteries have been developed that provide non-flammability, flame retardancy, or self-extinguishing properties, and greatly reduce the risk of ignition of the battery in the event of a short circuit or other accident (see WO 02/21631). Issue pamphlet and International Publication No. 03Z041197 pamphlet).

Disclosure of the invention

[0006] However, even if a phosphazene compound is added to the non-aqueous electrolyte for the battery, if the battery starts to run away due to, for example, being exposed to an abnormally high temperature, the battery runs out of heat. Cannot be stopped on the way. Accordingly, there is a need for a non-aqueous electrolyte additive for a battery that can reduce the risk of ignition and ignition of the battery and at the same time suppress thermal runaway.

[0007] Therefore, an object of the present invention is to provide an additive for an electrolyte of a nonaqueous electrolyte battery that can increase the thermal runaway start temperature of the nonaqueous electrolyte battery as compared with a conventional additive for electrolyte. Is to provide. Another object of the present invention is to provide a non-aqueous electrolyte for a battery containing such an additive, and a non-aqueous electrolyte battery comprising the non-aqueous electrolyte and having a significantly improved thermal runaway start temperature. is there.

[0008] As a result of diligent studies to achieve the above object, the present inventor has added a cyclic phosphazene compound having a specific structure to the non-aqueous electrolyte so that the thermal runaway start temperature of the non-aqueous electrolyte battery can be increased. Has been found to increase significantly, and the present invention has been completed.

That is, the additive for electrolyte solution of the nonaqueous electrolyte battery of the present invention has the following formula (I):

(NPX) (1)

2 n

[In the formula, each X is independently F or C1, provided that all X are not the same.

N is 3 or 4, and is characterized by comprising a phosphazene compound in which the number of C1 bonded to each P is 0 or 1.

[0010] In a preferred example of the additive for an electrolyte solution of the nonaqueous electrolyte battery of the present invention, n in the formula (I) is 3, and among 6 Xs:! To 3 are C1 is there.

[0011] In another preferred embodiment of the additive for electrolyte solution of the nonaqueous electrolyte battery of the present invention, the above formula (I)

N in the middle is 4, and 2 to 4 out of 8 X's are C1.

[0012] Further, a nonaqueous electrolytic solution for a battery of the present invention is characterized by containing the above-mentioned additive for electrolytic solution, an aprotic organic solvent, and a supporting salt.

[0013] Further, the non-aqueous electrolyte battery of the present invention comprises the above non-aqueous electrolyte for a battery, a positive electrode, and a negative electrode. It can be either a primary battery or a secondary battery. Here, the non-aqueous electrolyte battery of the present invention preferably has a thermal runaway start temperature of 200 ° C or higher.

[0014] According to the present invention, an electrolyte solution for a nonaqueous electrolyte battery, which is composed of a cyclic phosphazene compound having a specific structure and can significantly increase the thermal runaway start temperature of the nonaqueous electrolyte battery, is provided. Additives can be provided. Further, it is possible to provide a nonaqueous electrolytic solution for a battery containing the additive and having greatly improved safety. Furthermore, a non-aqueous electrolyte battery provided with the non-aqueous electrolyte for the battery and having a significantly improved thermal runaway temperature can be provided.

Brief Description of Drawings

FIG. 1 shows a GC-MS GC chart of the reaction mixture obtained in Synthesis Example 1.

FIG. 2 shows the results of ARC analysis of non-aqueous electrolyte secondary batteries of conventional and comparative examples:!

FIG. 3 shows the results of ARC analysis of the non-aqueous electrolyte secondary batteries of the conventional example, the comparative example 4 and the example.

BEST MODE FOR CARRYING OUT THE INVENTION

[0016] The present invention is described in detail below.

The additive for electrolyte solution of the nonaqueous electrolyte battery of the present invention is characterized by comprising a cyclic phosphazene compound represented by the above formula (I) and having 0 or 1 C1 bonded to each P. The phosphazene compound has an effect of suppressing the exothermic reaction of the non-aqueous electrolyte and suppresses thermal runaway of the battery, and the non-aqueous electrolyte provided with the non-aqueous electrolyte containing the phosphazene compound Liquid batteries have high safety due to high thermal runaway start temperature. In addition, the phosphazene compound generates nitrogen gas and / or phosphate ester in an emergency of a non-aqueous electrolyte battery, thereby making the non-aqueous electrolyte non-flammable, flame retardant, or self-extinguishing. It also has the effect of greatly reducing the risk of such problems.

[0017] The phosphazene compound constituting the additive for electrolyte of the nonaqueous electrolyte battery of the present invention is represented by the above formula (I). In the formula (I), each X is independently F or C1, provided that all Xs are not the same. Note that the use of a compound containing a halogen element may cause the generation of halogen radicals. The phosphazene compound described above forms phosphorus halides because the phosphorus element in the molecule traps the halogen radicals. The problem is Does not occur.

[0018] In the formula (I), n is 3 or 4. When n is 5 or more, efficient synthesis of phosphazene compounds becomes difficult, which is preferable. Here, the viscosity of the phosphazene compound at 25 ° C. is more preferably 5 mPa ′s or less, preferably lOmPa ′s or less, from the viewpoint of sufficiently securing the charge / discharge characteristics of the battery. In the present invention, the viscosity is measured using a viscosity meter [R-type viscometer Model RE500_SL, manufactured by Toki Sangyo Co., Ltd.], lrpm, 2 mm, 3 rpm, 5 rpm, 7 rpm, lOrpm, 20 rpm and 50 mm. Measured at each rotational speed of m for 120 seconds, the rotational speed at the indicated value of 50-60% is taken as the analysis condition, and the value measured at that time.

[0019] Further, in the formula (I), the number of C1 bonded to each P is 0 or 1. A phosphazene compound in which two C 1s are bonded to one P, the electrons of P are attracted to two C1 and P is positive, and the electron orbit of C1 and the electron orbit of P The reduction potential of P is lowered due to the degeneracy of the lowest unoccupied molecular orbital consisting of. Also, since C1 is a large element, it is easy to desorb because of its steric hindrance. Therefore, a phosphazene compound in which two C1s are bonded to one P is insufficient in the effect of suppressing the thermal runaway of a highly reactive battery, and can sufficiently raise the thermal runaway start temperature of the battery. Nare ,. In addition, when such a compound is used as an additive, the phosphazene compound may undergo reductive decomposition depending on the potential used, and may not be satisfactory as a battery function. [Hereinafter, two C1 in one P] A phosphazene compound in which is bonded is referred to as a geminal isomer, and a phosphazene compound in which each C1 is bonded to P is sometimes referred to as a non-geminal isomer].

[0020] Among the above phosphazene compounds, from the viewpoint of a low freezing point, n in the formula (I) is 3, and 1 to 3 out of 6 Xs are C1 and the residual force, and the formula (I) is the n force, and 2 to 4 out of 8 Xs are C1 and the rest are F. The freezing point of the phosphazene compound which is X force or C1 in formula (I) is shown in Table 1 together with boiling point and viscosity at 25 ° C. [0021]

[0022] As is apparent from Table 1, in the phosphazene compound in which X in formula (I) is F or C1, Although the boiling point rises as the CI number increases (increased molecular weight), the freezing point is minimum in a specific C1 number range, and when n is 3, the C1 number is preferably in the range of 1-3. When n is 4, the number of C1 is preferably in the range of 2-5. Here, the phosphazene compound preferably has a freezing point of 10 ° C or lower. By adding a phosphazene compound having a freezing point of 10 ° C or lower to the non-aqueous electrolyte, the low-temperature characteristics of the non-aqueous electrolyte battery can be improved.

[0023] The phosphazene compound is synthesized, for example, by reacting a commercially available phosphazene compound represented by (NPC1) with a fluorinating agent such as sodium fluoride (NaF) in a nitrobenzene solvent and partially fluorinating it. it can. As a conventional synthesis method, the synthesis method described in J. Chem. Soc, ser. A., pp. 2590 81968 is known. Since the synthesis method has a low yield, the inventor has made his own The synthesis process was used. More specifically, when synthesizing a phosphazene compound represented by the formula (I), n = 3, and C1 / F ratio of 1/5, 2/4, 3/3, 0.4M of (NPC1) First, react 2 equivalents of NaF with the nitrobenzene solution, then add a very small amount of water, then react with 1 equivalent of NaF, and then distill under reduced pressure to obtain each phosphazene compound. Can do. In particular, to obtain a phosphazene compound with a high C1 ratio, the amount of NaF added can be reduced. Conversely, to reduce the C1 / F ratio, the amount of NaF added can be increased. . In this synthesis method, a phosphazene compound having a desired C1 / F ratio can be synthesized by changing the ratio of (NPC1) / NaF. The above phosphazene compounds may be used alone or as a mixture of two or more.

<Non-aqueous electrolyte for battery>

A non-aqueous electrolyte for a battery according to the present invention includes the above-described additive for a non-aqueous electrolyte, an aprotic organic solvent, and a supporting salt. Thermal runaway is suppressed and ignition is performed. 'Bow | The risk of fire is very low.

[0025] The aprotic organic solvent used in the battery non-aqueous electrolyte of the present invention is not particularly limited, but ether compounds and ester compounds are preferred from the viewpoint of keeping the viscosity of the electrolyte low. Les. Specifically, 1,2-dimethoxyethane (DME), tetrahydrofuran (THF), dimethyl carbonate (DMC), jetyl carbonate (DEC), diphenyl carbonate, ethylene carbonate (EC), propylene carbonate ( PC), γ _ butyro rataton ( GBL), y-valerolatatone, ethylmethyl carbonate (EMC), methyl formate (MF) and the like are preferable. Among these, as the aprotic organic solvent for the non-aqueous electrolyte solution of the primary battery, cyclic ester compounds such as propylene carbonate and y-butylate rataton, chain ester compounds such as dimethyl carbonate and ethylmethyl carbonate, While chain ether compounds such as 1,2-dimethoxyethane are preferred, aprotic organic solvents for non-aqueous electrolytes for secondary batteries include ethylene carbonate, propylene carbonate, Preference is given to cyclic ester compounds such as ratatones, chain ester compounds such as dimethyl carbonate, ethylmethyl carbonate and jetyl carbonate, and chain ether compounds such as 1,2-dimethoxyethane. In particular, a cyclic ester compound is suitable in that it has a high relative dielectric constant and is excellent in solubility, such as a lithium salt. A chain ester ic compound and an ether compound are low in viscosity, and thus have a low viscosity. It is suitable in terms of chemical conversion. These may be used alone or in combination of two or more, but it is preferable to use in combination of two or more. The viscosity of the aprotic organic solvent at 25 ° C. is not particularly limited, but is preferably 10 mPa ′ s (10 cP) or less, more preferably 5 mPa ′ s (5 cP) or less.

[0026] The supporting salt used in the non-aqueous electrolyte for a battery of the present invention is preferably a supporting salt serving as a lithium ion source. The supporting salt is not particularly limited, but examples thereof include LiCIO, Li

BF, LiPF, LiCF SO, LiAsF, LiC F SO, Li (CF SO) N and Li (C F SO)

Preferable examples include lithium salts such as N. These supporting salts can be used alone or as a mixture of two or more.

[0027] The concentration of the supporting salt in the non-aqueous electrolyte for a battery of the present invention is preferably in the range of 0.2 to 1.5 mol / L (M), more preferably in the range of 0.5 to lmol / L (M). Masle. If the concentration of the supporting salt is less than 0.2 mol / L, sufficient conductivity of the electrolyte cannot be ensured, which may hinder battery discharge and charge characteristics. In addition, since the viscosity of the electrolytic solution increases and the mobility of lithium ions cannot be secured sufficiently, the conductivity of the electrolytic solution cannot be secured sufficiently as described above, and the discharge characteristics and charging characteristics of the battery may be hindered. is there.

[0028] The content of the phosphazene compound (that is, the content of the additive) in the nonaqueous electrolytic solution for a battery of the present invention improves the safety of the electrolytic solution and sufficiently increases the thermal runaway start temperature of the battery. From the viewpoint of making it, 2% by volume or more is preferable, and 5% by volume or more is more preferable. [0029] <Nonaqueous electrolyte battery>

The non-aqueous electrolyte battery of the present invention includes the above-described non-aqueous electrolyte for a battery, a positive electrode, and a negative electrode, and is usually used in the technical field of non-aqueous electrolyte batteries such as a separator as necessary. Other members are provided, and the battery may be a primary battery or a secondary battery. Since the non-aqueous electrolyte solution containing the above-mentioned additive is used in the non-aqueous electrolyte battery of the present invention, the thermal runaway start temperature of the battery in ARC analysis is high, preferably the thermal runaway start temperature is 200. ° C or higher.

[0030] The positive electrode active material of the non-aqueous electrolyte battery of the present invention is partially different between the primary battery and the secondary battery. For example, as the positive electrode active material of the non-aqueous electrolyte primary battery, fluorinated graphite [( CF)], MnO (electrical n 2 chemical synthesis or chemical synthesis), VO, MoO, Ag CrO, CuO, Cu

2 5 3 2 4

S, FeS, SO, SOC1, TiS, etc. are preferred, among which high capacity and safety

2 2 2 2

MnO, fluorinated black in terms of excellent wettability of electrolyte with high discharge potential and high discharge potential

2 Lead is preferred. These positive electrode active materials may be used alone or in combination of two or more.

On the other hand, as the positive electrode active material of the non-aqueous electrolyte secondary battery, V 2 O, V 0, MnO, MnO

Metal oxides such as 2 5 6 13 2 3, lithium such as LiCoO, LiNiO, LiMn O, LiFeO and LiFePO

2 2 2 4 2 4

Containing complex oxides, metal sulfides such as TiS and MoS, conductive polymers such as polyaniline, etc.

twenty two

Are preferable. The lithium-containing composite oxide may be a composite oxide containing two or three transition metals selected from the group consisting of Fe, Mn, Co and Ni. In this case, the composite oxide is LiFe Co Ni O [where 0≤χ <1, 0≤y <l, 0 <x + y

(Ι 2

≤1] or LiMn Fe〇 etc. Among these, high capacity and high safety

2

In addition, LiCoO, LiNiO, and LiMn O are particularly suitable because of their excellent electrolyte wettability.

2 2 2 4

is there. These positive electrode active materials may be used alone or in combination of two or more.

[0032] The negative electrode active material of the non-aqueous electrolyte battery of the present invention is partially different between the primary battery and the secondary battery. For example, the negative electrode active material of the non-aqueous electrolyte primary battery includes lithium metal itself. And lithium alloys. Examples of metals that form alloys with lithium include Sn, Pb, Al, Au, Pt, In, Zn, Cd, Ag, and Mg. Among these, Al, Zn, and Mg are preferable from the viewpoints of reserves and toxicity. These negative electrode active materials may be used alone or in combination of two or more May be used in combination.

[0033] On the other hand, as the negative electrode active material of the non-aqueous electrolyte secondary battery, lithium metal itself, an alloy of lithium and A1, In, Pb, Zn or the like, a carbon material such as graphite doped with lithium, or the like is preferable. Among these, graphite, which is preferred for a carbon material such as graphite, is particularly preferred because it has higher safety and is superior in wettability of an electrolyte. Here, examples of graphite include natural graphite, artificial black lead, mesophase carbon microbeads (MCMB), and the like, and widely include graphitizable carbon and non-graphitizable carbon. These negative electrode active materials may be used alone or in combination of two or more.

[0034] The positive electrode and the negative electrode can be mixed with a conductive agent and a binder as necessary. Examples of the conductive agent include acetylene black, and the binder is polyvinylidene fluoride (PVDF). , Polytetrafluoroethylene (PTFE), styrene butadiene rubber (SBR), strong ruxymethyl cellulose (CMC), and the like. These additives can be used at the same mixing ratio as before.

[0035] The shape of the positive electrode and the negative electrode can be appropriately selected as a medium force known in the art as an electrode without particular limitation. For example, a sheet shape, a columnar shape, a plate shape, a spiral shape, and the like can be given.

[0036] As another member used in the non-aqueous electrolyte battery of the present invention, a separator interposed between the positive and negative electrodes in the role of preventing current short-circuiting due to contact of both electrodes in the non-aqueous electrolyte battery. Is mentioned. As the material of the separator, a material that can reliably prevent contact between both electrodes and that can pass or contain an electrolyte solution, such as polytetrafluoroethylene, polypropylene, polyethylene, cenorelose, polybutylene terephthalate, polyethylene A non-woven fabric made of a synthetic resin such as phthalate, a thin layer film and the like are preferable. Among these, polypropylene or polyethylene microporous film having a thickness of about 20 to 50 μm, and vinylome such as cenorelose, polybutylene terephthalate, and polyethylene terephthalate are particularly suitable. In the present invention, in addition to the separators described above, known members that are normally used in batteries can be suitably used.

[0037] The form of the non-aqueous electrolyte battery of the present invention described above is not particularly limited, such as a coin type, a button type, a paper type, a square type or a spiral type cylindrical battery. Various known forms are preferred. In the case of the button type, a non-aqueous electrolyte battery can be produced by preparing a sheet-like positive electrode and negative electrode and sandwiching a separator between the positive electrode and the negative electrode. Further, in the case of the spiral structure, for example, it is possible to produce a nonaqueous electrolyte battery by stacking and winding up a sheet-like positive electrode and a negative electrode through a separator.

[0038] <Example>

Hereinafter, the present invention will be described in more detail with reference to examples. However, the present invention is not limited to the following examples.

A 0.4M (NPC1) nitrobenzene solution was reacted with 2 equivalents of NaF for the first time, and then a very small amount of water was added, followed by 1 equivalent of NaF. The obtained reaction mixture was distilled under reduced pressure, represented by the formula (I), n = 3, C1 / F ratio was 1/5, 2/4 (geminal and non-geminal), 3/3 Of phosphazene compounds were obtained. Figure 1 shows a GC chart of GC-MS analysis of the reaction mixture before distillation under reduced pressure.

[0040] <Preparation of non-aqueous electrolyte for battery>

Next, 90% by volume of a mixed solvent of ethylene carbonate (EC) and ethylmethyl carbonate (EMC) (EC / EMC volume ratio = 1/2), 10 volumes of a phosphazene compound (additive) with the structure shown in Table 2 A nonaqueous electrolyte was prepared by dissolving LiPF (supporting salt) at a concentration of 1M (mol / L) in the resulting mixed solution. The conventional non-aqueous electrolyte was prepared by dissolving LiPF at a concentration of 1M in a mixed solvent of EC and EMC (EC / EMC volume ratio = 1/2).

[0041] <Preparation of non-aqueous electrolyte secondary battery>

Add 94 parts by mass of LiCoO (positive electrode active material) with 3 parts by mass of acetylene black (conductive agent) and 3 parts by mass of polyvinylidene fluoride (binder), and add an organic solvent (ethyl acetate and ethanol). 50% / 50% by mass mixed solvent), and the kneaded product is applied to a 25 μm thick aluminum foil (current collector) with a doctor blade, followed by hot air drying (100-120 ° C) Thus, a positive electrode sheet having a thickness of 80 μπι was prepared. Also, 3 parts by mass of acetylene black (conductive agent) and 3 parts by mass of polyvinylidene fluoride (binder) are added to 94 parts by mass of graphite (carbon material), and organic After kneading in a solvent (50/50 wt% mixed solvent of acetic acid Echiru and ethanol), it was coated with a doctor blade to an aluminum foil having a thickness of 25 mu _m and kneaded mixture (collector), dried with hot air ( 100 to 120 ° C.) to prepare a negative electrode sheet having a thickness of 150 μm. The positive electrode sheet and the negative electrode sheet were overlapped and rolled up through a separator (microporous film: made of polypropylene) having a thickness of 25 μm to produce a cylindrical electrode. The positive electrode length of the cylindrical electrode was about 260 mm. The above electrolytic solution was injected into the cylindrical electrode and sealed to prepare an AA lithium battery (nonaqueous electrolyte secondary battery). The obtained battery was charged under the conditions of 4.2 V and 3.7 mAh, and then ARC analysis was performed by the following method. The results are shown in FIGS. 2 and 3 and Table 2.

[0042] (1) ARC analysis method

Under the measurement conditions of start temperature = 50 ° C, end temperature = 350 ° C, temperature step = 5 ° C, temperature sensitivity = 0.02 ° C / min, standby time = 17 minutes, analysis step temperature = 0.2 ° C, Thermal ARC analysis was performed on the batteries using an ARC device manufactured by Hazar d Technology. In Fig. 2 and Fig. 3, in the stepped region, the battery did not run out of heat, and the temperature was raised by applying heat from the outside, and the thermal runaway start temperature was obtained from the last step. In addition, the self-heating rate was obtained from the slope at the thermal runaway start temperature.

[0043] Table 2

[0044] As is clear from Table 1, it is represented by the formula (I), and X is F or C1, provided that all Xs are not the same. By adding a phosphazene compound in which n is 3 or 4 and the number of C1 bonds to each P is 0 or 1, to the non-aqueous electrolyte, the thermal runaway start temperature of the non-aqueous electrolyte battery can be increased. It is out.

Claims

The scope of the claims

[1] The following formula (I):

(NPX)… (I)

2 n

N is 3 or 4, and an additive for an electrolyte of a non-aqueous electrolyte battery comprising a phosphazene compound in which the number of C1 bonded to each P is 0 or 1.

[2] The electrolyte for a nonaqueous electrolyte battery according to claim 1, wherein n in the formula (I) is 3, and 1 to 3 of 6 Xs are C1. Additive.

[3] The electrolyte for a non-aqueous electrolyte battery according to claim 1, wherein n in the formula (I) is 4, and 2 to 4 of 8 Xs are C1. Additive.

[4] Claims: A nonaqueous electrolytic solution for a battery comprising the additive for electrolytic solution according to any one of! To 3, an aprotic organic solvent, and a supporting salt.

[5] A nonaqueous electrolyte battery comprising the battery nonaqueous electrolyte according to claim 4, a positive electrode, and a negative electrode.

[6] The nonaqueous electrolyte battery according to [5], wherein the thermal runaway start temperature is 200 ° C or higher.