JP5228393B2 - Lithium ion secondary battery - Google Patents

Description

  The present invention relates to a non-aqueous electrolyte battery in which a negative electrode operates exclusively at a potential of 1.2 V or more.

  In recent years, small and lightweight lithium ion secondary batteries have been widely used as power sources for electronic devices such as mobile phones and digital cameras. Lithium ion secondary batteries generally use lithium transition metal composite oxides for the positive electrode, carbon materials for the negative electrode, and carbonates containing lithium salts for the electrolyte, and the battery has a high energy density. Has been put to practical use.

  In addition, a lithium ion secondary battery using lithium titanate, which is an active material having a small volume change accompanying charging and discharging at the negative electrode, has been put into practical use. Non-aqueous electrolyte batteries using such a negative electrode active material with little volume change are often used for backup power supply applications, and in particular, have low self-discharge (excellent storage performance) and 80 ° C to -30 ° C. Highly reliable performance such as high output performance over a wide range of temperatures is strongly demanded.

This lithium ion secondary battery has the feature that the self-discharge is extremely small in a wide temperature range, and Non-Patent Document 1 suppresses problems such as battery capacity reduction and gas generation due to capacity balance deviation between the positive electrode and the negative electrode. However, a non-aqueous electrolyte battery with improved reliability in a high temperature environment at 60 ° C. to 80 ° C. has been reported. Patent Document 1 discloses a non-aqueous electrolyte battery including a negative electrode having a negative electrode active material into which lithium ions are inserted and desorbed at a potential of 1.2 V or more with respect to the lithium potential. There is a coating having a structure of 10 nm or more having a structure, and gas generation can be suppressed by using the nonaqueous electrolyte battery in a region of a negative electrode potential nobler than 0.8 V with respect to the lithium potential. Have been described.
Abstracts of the 73rd Annual Meeting of the Electrochemical Society of Japan. 2006, p257 International Publication No. 2007/064046 Pamphlet

  However, the nonaqueous electrolyte battery includes a negative electrode having a negative electrode active material into which lithium ions are inserted and desorbed at a potential of 1.2 V or more with respect to the lithium potential, and the negative electrode is 10 nm on the surface of the active material. In the case of including a negative electrode active material in which a film having the above carbonate structure is present, the reliability under a high temperature environment at 60 ° C. to 80 ° C. is high, but the influence of the presence of a film component on the negative electrode active material In particular, there is a problem that the low-temperature output characteristics at 0 ° C. or lower are greatly deteriorated. This is a point that does not cause a problem when a film having a carbonate structure of 10 nm or more is not present on the surface of the negative electrode active material.

  In view of the above problems, the present invention provides a non-aqueous electrolyte battery that maintains high output characteristics even at low temperatures while ensuring excellent reliability at high temperatures by the negative electrode active material comprising a coating component. Objective.

The present invention relates to a lithium ion secondary battery (hereinafter referred to as “a negative electrode including a negative electrode active material in which an electrochemical oxidation reaction accompanying a battery discharge is mainly performed at a potential of 1.2 V or higher”, a positive electrode, and a non-aqueous electrolyte). in.) referred to as "non-aqueous electrolyte battery", the negative electrode active material, the ratio of the average primary particle diameter to the average secondary particle diameter is not less than 0.05, an average secondary particle diameter is not more 15μm or less, and The non-aqueous electrolyte battery is characterized in that the average primary particle diameter is 0.8 μm or more.

  In addition, the negative electrode includes a negative electrode active material in which a film having a carbonate structure having a thickness of 10 nm or more is present on the surface.

Here, the non-aqueous electrolyte battery provided with the negative electrode active material in which the electrochemical oxidation reaction accompanying the discharge of the battery is mainly performed at a potential of 1.2 V or more is a usage environment in which the completed non-aqueous electrolyte battery is recommended. When a normal discharge is performed below, the open circuit potential exhibited by the negative electrode active material corresponding to the various depths of discharge during the discharge is exclusively the potential exhibited by metallic lithium in the non-aqueous electrolyte. A battery provided with a negative electrode active material that is 1.2 V (vs. Li ^/ Li ⁺ ) or higher. Therefore, for example, carbon materials that can occlude and release Li, such as graphite and hard carbon, are not included.

  One particle of the negative electrode active material is premised on secondary particles formed by aggregating primary particles. Therefore, when the average primary particle size is r1 and the average secondary particle size is r2, the ratio of the average primary particle size to the average secondary particle size (r1 / r2) is necessarily less than 1. In general, when the particle diameter of an active material is referred to as “particle diameter” without specifying primary or secondary, it corresponds to “secondary particle diameter” in the present specification.

  In the present specification, the average primary particle diameter r1 and the average secondary particle diameter r2 of the negative electrode active material are determined by an image analysis method based on observation with an electron microscope (SEM).

  Regarding the presence of a film having a carbonate structure of 10 nm or more on the surface of the negative electrode active material, the negative electrode active material particles (2) are removed from the battery without taking out the negative electrode plate and loosening the electrode. It can be confirmed by aiming at the surface of the secondary particles) and observing with an X-ray photoelectron spectrometer (XPS), analyzing the components, and measuring the thickness of the film having a carbonate structure. XPS measurement is performed by irradiating the sample with X-rays and observing the rebound data. When the minimum incident depth of X-rays is 10 nm, the surface layer portion within 10 nm is measured at the start of measurement. Information is obtained as averaged data. Therefore, for example, when both the information on the film having a carbonate structure and the information on the active material appear at the start of measurement, the thickness of the film can be determined to be less than 10 nm, and only the information on the film having a carbonate structure can be obtained at the start of measurement. When it appears, it can be determined that the thickness of the coating is 10 nm or more.

  According to the present invention, a nonaqueous electrolyte battery excellent in low temperature performance can be provided.

The negative electrode active material in which the electrochemical oxidation reaction accompanying the discharge of the battery is mainly performed at a potential of 1.2 V or higher is not limited at all. For example, Li ₄ Ti ₅ O ₁₂ , LiTiO ₂ , LiNb ₂ O ₅ Etc. Among these, lithium titanate represented by Li _x Ti _y O ₄ (1.0 ≦ x ≦ 2.4, 1 ≦ y ≦ 2) is preferable. Here, a part of the Ti site constituting the crystal structure of lithium titanate, or a part of the Ti site and the Li site may be substituted with another element.

  As described above, in order to achieve the object of the present invention, the ratio (r1 / r2) between the average primary particle diameter r1 and the average secondary particle diameter r2 of the negative electrode active material used in the present invention is 0.05 or more. It is necessary. The reason why the low-temperature output performance deteriorates when the value of r1 / r2 is less than 0.05 is not necessarily clear, but the present inventors estimate as follows. That is, the coating component having a carbonate structure is also formed on the surface of the primary particles, but when the primary particles form densely packed secondary particles, in other words, when the r1 / r2 ratio is small, the surface of the secondary particles As a result, the ion transfer distance from the primary particle to the primary particle inside the secondary particle becomes longer, and the film component formed on the primary particle becomes an adverse effect of the ion transfer, resulting in an increase in the apparent liquid resistance. It is presumed that the primary particles inside the secondary particles cannot contribute to the electrochemical reaction and the output performance is lowered.

  The upper limit of the value of r1 / r2 is less than 1 according to the definition of primary particles and secondary particles described above, and among these, 0.4 or less is preferable.

  Furthermore, in order to achieve the object of the present invention, the average secondary particle diameter r2 needs to be 15 μm or less. The reason why the low-temperature output performance decreases when the average secondary particle diameter r2 exceeds 15 μm is not necessarily clear, but the present inventors estimate as follows. In other words, it is presumed that the effective reaction surface area of the active material is lowered and the output performance is lowered.

  The lower limit of the average secondary particle diameter r2 is not particularly limited. However, if the average secondary particle diameter r2 is 0.8 μm or more, a relatively large amount of binder is required, which may result in poor output performance. Is preferable. Moreover, if the average primary particle diameter r1 is 0.8 μm or more, the primary particles constituting the secondary particles become too dense, and the electrolyte does not spread on the surface of each primary particle, so that the battery performance is improved. This is preferable because the possibility of being inferior is reduced.

  The primary particle size and the secondary particle size can be adjusted by pulverization and sieving of the negative electrode active material, as shown in Examples described later. Depending on the type of the negative electrode active material, the negative electrode active material may be adjusted according to the production conditions such as firing.

  The method for including the negative electrode active material in which the negative electrode includes a film having a carbonate structure of 10 nm or more on the surface is not limited, but as disclosed in Patent Document 1 or described later. As shown in the examples, this can be achieved by setting the depth of charge deeply so that the negative electrode potential becomes lower during the initial charge / discharge step before completion of the nonaqueous electrolyte battery.

  There is no restriction | limiting in particular as a binder used for the negative electrode of this invention, A various material can be used suitably. For example, styrene-butadiene rubber (SBR) or carboxymethylcellulose (CMC), polyvinylidene fluoride (PVdF), carboxy-modified polyvinylidene fluoride, polytetrafluoroethylene, tetrafluoroethylene-hexafluoropropylene copolymer, vinylidene fluoride-chloro Trifluoroethylene copolymer, polyvinylidene fluoride-hexafluoropropylene copolymer, ethylene-propylene-diene copolymer, acrylonitrile-butadiene rubber, fluororubber, polyvinyl acetate, polymethyl methacrylate, nitrocellulose, polyethylene, polypropylene or At least one selected from the group consisting of these derivatives and the like can be used.

  As the solvent used for mixing the binder, a non-aqueous solvent or an aqueous solution can be used. Non-aqueous solvents include N-methyl-2-pyrrolidone, dimethylformamide, dimethylacetamide, methyl ethyl ketone, cyclohexanone, methyl acetate, methyl acrylate, diethyltriamine, NN-dimethylaminopropylamine, ethylene oxide, tetrahydrofuran, etc. Can do. Moreover, you may add a dispersing agent, a thickener, etc. to these.

Various materials can be appropriately used as the compound that absorbs and releases lithium ions used in the positive electrode active material of the present invention. For example, transition metal compounds such as manganese dioxide and vanadium pentoxide, transition metal chalcogen compounds such as iron sulfide and titanium sulfide, and composite oxide Li _x MO _2-δ of these transition metals and lithium (however, , M represents Co, Ni, or Mn, and 0.4 ≦ x ≦ 1.2 and 0 ≦ δ ≦ 0.5), or these composite oxides may include Al, Mn, Fe, Ni , Co, Cr, Ti, and Zn, or at least one element selected from the group consisting of Zn, or nonmetallic elements such as P and B can be used.

Further, the composite oxide of lithium and nickel, i.e. the positive electrode active material (however represented by _{LiNi p M1 q M2 r O 2} -δ, M1, M2 is Al, Mn, Fe, Ni, Co, Cr, Ti, and It represents at least one element selected from the group consisting of Zn, or a nonmetallic element such as P or B, 0.4 ≦ x ≦ 1.2, 0.8 ≦ p + q + r ≦ 1.2, 0 ≦ δ ≦ Composite oxide of 0.5) or the like can be used. Among these, lithium-cobalt composite oxides and lithium-cobalt-nickel composite oxides are preferable because high voltage, high energy density are obtained, and cycle performance is excellent.

  There is no restriction | limiting in particular as an organic solvent of the electrolyte solution used for the nonaqueous electrolyte battery of this invention, A various material can be used suitably. For example, ethers, ketones, lactones, nitriles, amines, amides, sulfur compounds, halogenated hydrocarbons, esters, carbonates, nitro compounds, phosphate ester compounds, sulfolane hydrocarbons, etc. Among these, ethers, ketones, esters, lactones, halogenated hydrocarbons, carbonates, and sulfolane hydrocarbons are preferable. Further examples of these include tetrahydrofuran, 2-methyltetrahydrofuran, tetrahydropyran, 1,4-dioxane, anisole, monoglyme, 4-methyl-2-pentanone, methyl acetate, ethyl acetate, methyl propionate, ethyl propionate, 1,2-dichloroethane, γ-butyrolactone, γ-valerolactone, dimethoxyethane, diethoxyethane, methyl formate, dimethyl carbonate, methyl ethyl carbonate, diethyl carbonate, dipropyl carbonate, methyl propyl carbonate, ethylene carbonate, propylene carbonate, Vinylene carbonate, butylene carbonate, dimethylformamide, dimethyl sulfoxide, dimethylthioformamide, sulfolane, 3-methyl-sulfo Examples thereof include run, trimethyl phosphate, triethyl phosphate, and phosphazene derivatives, and mixed solvents thereof. Especially, it is preferable to use ethylene carbonate, propylene carbonate, (gamma) -butyrolactone, dimethyl carbonate, methyl ethyl carbonate, and diethyl carbonate individually or in mixture of 2 or more types.

Moreover, there is no restriction | limiting in particular as a solute used for the nonaqueous electrolyte battery of this invention, A various solute can be used suitably. For example, LiClO ₄ , LiBF ₄ , LiAsF ₆ , LiPF ₆ , LiPF (CF ₃ ) ₅ , LiPF ₂ (CF ₃ ) ₄ , LiPF ₃ (CF ₃ ) ₃ , LiPF ₄ (CF ₃ ) ₂ , LiPF ₅ (CF ₃ ), LiPF ₃ (C ₂ F ₅ ) ₃ , LiCF ₃ SO ₃ , LiN (CF ₃ SO ₂ ) ₂ , LiN (C ₂ F ₅ SO ₂ ) ₂ , LiN (C ₂ F ₅ CO) ₂ , LiI, LiAlCl ₄ , LiBC ₄ O ₈ or the like can be used alone or in admixture of two or more. Of these, LiPF ₆ is preferably used because of its good ion conductivity. Furthermore, the lithium salt concentration is preferably 0.5 to 2.0 mol / dm ³ .

Also included in the electrolyte are carbonates such as vinylene carbonate and butylene carbonate, benzenes such as biphenyl and cyclohexylbenzene, sulfurs such as propane sultone, ethylene sulfide, hydrogen fluoride, triazole-based cyclic compounds, fluorine-containing esters, tetraethylammonium It can be used even if it contains at least one selected from the group consisting of fluoride fluoride complexes or derivatives thereof, phosphazenes and derivatives thereof, amide group-containing compounds, imino group-containing compounds, or nitrogen-containing compounds. _{Moreover, CO 2, NO 2, CO} , also contain at least one selected from such SO ₂ may be used.

  There is no restriction | limiting in particular as a separator used for the nonaqueous electrolyte battery of this invention, A various material can be used suitably. For example, a woven fabric, a nonwoven fabric, a synthetic resin microporous film, etc. are mentioned, and among them, a synthetic resin microporous film is preferable. As the material of the synthetic resin microporous membrane, nylon, cellulose acetate, nitrocellulose, polysulfone, polyacrylonitrile, polyvinylidene fluoride, and polyolefins such as polyethylene, polypropylene, and polybutene are used. Among them, polyethylene and polypropylene microporous membranes, Alternatively, a polyolefin microporous film such as a microporous film obtained by combining these is preferable in terms of thickness, film strength, film resistance, and the like. In addition, materials, laminates of multiple microporous membranes with different weight average molecular weights and porosity, and appropriate additives such as various plasticizers, antioxidants, and flame retardants are contained in these microporous membranes You can use what you are doing.

In addition, a solid or gel ion conductive electrolyte can be used alone or in combination for the electrolyte. In the case of combination, the structure of the electrochemical capacitor includes a combination of a positive electrode, a negative electrode and a separator, an organic or inorganic solid electrolyte and the above non-aqueous electrolyte, or an organic or inorganic solid electrolyte membrane as a positive electrode, a negative electrode and a separator, and the above A combination with a non-aqueous electrolyte is mentioned.
The shape of the nonaqueous electrolyte battery of the present invention is not particularly limited, and can be applied as various shapes such as a square, an ellipse, a cylinder, a coin, a button, a sheet, or a battery.

  Next, a preferred embodiment of the present invention will be described. However, the present invention is not limited to the following examples.

[ Reference Example 1]
First, titanium oxide (TiO ₂ , rutile ratio 90%) and Li ₂ CO ₃ were weighed so that the Li / Ti molar ratio was 0.8, and mixed in a mortar for 30 minutes. This mixture was placed in a ceramic boat and pre-baked in an electric furnace at 700 ° C. for 4 hours under oxygen flow (0.1 liter / min). Next, this temporarily fired body was fired in an electric furnace at 800 ° C. for 5 hours under oxygen flow (0.1 liter / min). The powder thus produced was pulverized with an automatic mortar to obtain a Li ₄ Ti ₅ O ₁₂ powder. When the particle size distribution of this powder was measured, it was found that a relatively wide distribution of about 0.5 μm to 40 μm was exhibited. The Li ₄ Ti ₅ O ₁₂ powder was pulverized for 10 hours using a ball mill and then fractionated using a 795 mesh (16 μm aperture) stainless steel sieve. Only the powder that passed through the sieve was mixed with acetylene black (conductive agent) and polyvinylidene fluoride (PVdF, binder) at a mass ratio of 87: 5: 8, and N-methyl-2-pyrrolidone (NMP). Was added and kneaded sufficiently to prepare a negative electrode paste. The negative electrode paste was applied to one side of a 15 μm thick copper foil and vacuum dried at 150 ° C. to evaporate NMP. Thereafter, it was compression molded by a roll press and cut into a size of 30 mm × 40 mm to produce a negative electrode containing Li ₄ Ti ₅ O ₁₂ as a negative electrode active material.

Subsequently, 90% by mass of lithium transition metal composite oxide (LiNi _1/3 Co _1/3 Mn _1/3 O ₂ ) powder as the positive electrode active material, 5% by mass of acetylene black, 5% by mass of polyvinylidene fluoride (PVdF) Was added to N-methylpyrrolidone (NMP) and mixed to form a slurry. This slurry was applied to one side of a current collector made of 20 μm aluminum foil, and vacuum dried at 150 ° C. to evaporate NMP. Then, it was compression molded with a roll press and cut into a size of 30 mm × 40 mm to produce a positive electrode containing LiNi _1/3 Co _1/3 Mn _1/3 O ₂ as a positive electrode active material.

Each of the positive electrode and the negative electrode is stacked with a polyethylene separator which is a continuous porous body having a thickness of 30 μm and a porosity of 40% interposed therebetween, and is inserted into a container having a height of 70 mm and a width of 50 mm made of an aluminum laminate sheet. In addition, a non-aqueous electrolyte was injected into the interior. In the non-aqueous electrolyte, LiPF ₆ was dissolved in a mixed solvent of ethylene carbonate (PC) and diethyl carbonate (DEC) in a volume ratio of 7: 3 so as to be 1 mol / dm ^3, and further 5% by mass. What added vinylene carbonate was used so that it might become. Thereafter, the cell is subjected to an initial charge / discharge process in which the cell is charged and discharged for 3 cycles in a voltage range of 4V-1V, thereby temporarily lowering the potential of the negative electrode of the cell to about 0.3 V (vs. Li ^/ Li ⁺ ). Thus, a protective film including a carbonate structure was formed on the surface of the negative electrode active material. The non-aqueous electrolyte battery of Example 1 was manufactured through the above steps. When this battery was disassembled and a negative electrode SEM image was taken with a scanning electron microscope, the average secondary particle size of the negative electrode active material was 0.89 μm, and the primary particle size was about 0.3 μm.

[Example 1 ]
In the negative electrode active material manufacturing method of Reference Example 1, the same nonaqueous electrolyte battery except that the ball mill pulverization time is 1 hour and the negative electrode active material is fractionated using 200 mesh instead of the 795 mesh stainless steel sieve The nonaqueous electrolyte battery of Example 2 was manufactured by the manufacturing method described above. The negative active material of the battery had an average secondary particle size of 15 μm and a primary particle size of about 0.9 μm.

[Example 2 ]
In the negative electrode active material manufacturing method of Reference Example 1, the same nonaqueous electrolyte battery manufacturing method except that ball milling is not performed and the negative electrode active material is fractionated using 440 mesh instead of 795 mesh stainless steel sieve. Thus, a nonaqueous electrolyte battery of Example 3 was manufactured. The negative active material of the battery had an average secondary particle size of 10 μm and a primary particle size of about 4 μm.

[Example 3 ]
In the negative electrode active material manufacturing method of Reference Example 1, the same nonaqueous electrolyte battery except that the ball mill pulverization time is 15 minutes and the negative electrode active material is fractionated using 440 mesh instead of the 795 mesh stainless steel sieve The nonaqueous electrolyte battery of Example 5 was manufactured by the manufacturing method described above. The negative active material of the battery had an average secondary particle size of about 10 μm and a primary particle size of about 2.5 μm.

[Comparative Example 1]
In the negative electrode active material manufacturing method of Reference Example 1, the same nonaqueous electrolyte battery except that the ball milling time is 24 hours and the negative electrode active material is fractionated using 200 mesh instead of the 795 mesh stainless steel sieve The non-aqueous electrolyte battery of Comparative Example 1 was manufactured by the manufacturing method. The negative active material of the battery had an average secondary particle size of 15 μm and a primary particle size of about 0.3 μm.

[Comparative Example 2]
Instead of the 795 mesh stainless steel sieve, the nonaqueous electrolyte battery of Comparative Example 2 was prepared in the same manner as the nonaqueous electrolyte battery of Reference Example 1 except that the negative electrode active material was fractionated using 60 mesh. Produced. The negative active material of this battery had an average secondary particle size of 20 μm and a primary particle size of about 4 μm.

[Comparative Example 3]
A coating component is not formed on the surface of the negative electrode active material by the same method as that for the non-aqueous electrolyte battery of Reference Example 1 except that the charge / discharge voltage range of 3 cycles in the initial charge / discharge process is 2.5V-1V. A nonaqueous electrolyte battery of Comparative Example 3 was produced.

[Comparative Example 4]
A coating component is not formed on the surface of the negative electrode active material by the same method as the method for manufacturing the nonaqueous electrolyte battery of Example 1 except that the charge / discharge voltage range of 3 cycles in the initial charge / discharge process is 2.5V-1V. A nonaqueous electrolyte battery of Comparative Example 4 was produced.

[Comparative Example 5]
A coating component is not formed on the surface of the negative electrode active material by the same method as that for the non-aqueous electrolyte battery of Example 2 except that the charge / discharge voltage range of 3 cycles in the initial charge / discharge process is 2.5V-1V. A nonaqueous electrolyte battery of Comparative Example 5 was produced.

The nonaqueous electrolyte batteries of Reference Example 1, Examples 1 to 3 and Comparative Examples 1 to 5 were connected to a charge / discharge device after being placed in a thermostat capable of temperature control from −30 ° C. to 80 ° C. Furthermore, after the temperature of the thermostatic chamber was raised to 80 ° C., a constant current-constant voltage charge of current 1 ItA to 2.5 V was performed for 3 hours, and a continuous cycle test of constant current discharge to 1.0 V of 1 ItA was performed. Table 1 shows the discharge capacity maintenance rate of each battery after 500 cycles of this charge / discharge continuous cycle test.

From Table 1, the batteries formed on the surfaces of the negative electrode active materials of Reference Example 1, Examples 1 to 3 and Comparative Examples 1 and 2 showed extremely excellent cycle characteristics even at a high temperature of 80 ° C. It can be seen that in the case of a non-aqueous electrolyte battery in which no film is formed on the surface of 3 to 5 negative electrode active materials, the discharge capacity is remarkably reduced. Thus, a battery that is significantly deteriorated at a high temperature is not suitable for a battery for high reliability.

Next, batteries according to Reference Example 1, Examples 1 to 3 and Comparative Examples 1 and 2 were separately prepared, and the output value P ₋ after 30 seconds after discharging the battery at −30 ° C. with respect to the output value P _{25 at} 25 ° C. seeking the percentage ratio of _30, which was defined as the low-temperature output performance value _(P -30 _/ P _25). The results are shown in Table 2. In addition, FIG. 1 plots the relationship between r1 and r2 for each example and comparative example, describes the low-temperature output performance value at the lower right of each point, and shows some points on the diagram. It showed about the value of r1 / r2 which is the reciprocal number of inclination.

Table, Example 1, the batteries of Examples 1~ _{3, P} -30 _/ P ₂₅ is showing a 10 higher than the value in Comparative Example 1 and 2, a low value of less than 10, high reliability It can be said that this is unsuitable for batteries. As shown in FIG. 1, an example battery using a negative electrode active material satisfying the condition that the average secondary particle diameter is 15 μm or less and the ratio of the average primary particle diameter to the average secondary particle diameter is 0.05 or more. It can be seen that the effect of the present invention is achieved.

In In current applications areas where capacitors are employed, with the current state or low temperature performance, and, when a large electrochemical devices electric capacity is demanded, the value of the P _{-30 /} P ₂₅ 10 or more If so, the industrial applicability is very large because it meets such needs.

It is a figure which shows the physical-property value and low-temperature output performance value of the negative electrode active material particle which concerns on an Example and a comparative example.

Claims (1)

In a non-aqueous electrolyte battery comprising a negative electrode including a negative electrode active material in which an electrochemical oxidation reaction accompanying discharge of a battery is mainly performed at a potential of 1.2 V or more, a positive electrode, and a non-aqueous electrolyte, the negative electrode has a surface Including a negative electrode active material in which a film having a carbonate structure having a thickness of 10 nm or more exists, and the negative electrode active material has a ratio of an average primary particle diameter to an average secondary particle diameter of 0.05 or more, and an average secondary A lithium ion secondary battery having a particle diameter of 15 μm or less and an average primary particle diameter of 0.8 μm or more.

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