TW492207B - Positive electrode active material, positive electrode active material composition and lithium ion secondary battery - Google Patents

Abstract

The present invention relates to a positive electrode active material, a negative electrode active material and an electrolyte that are used alone or in combination to improve charge and discharge cycle characteristic, low temperature characteristic and safety of a non-aqueous electrolyic secondary battery, particularly a lithium ion secondary battery. Specifically, a particulate Li-transition metal composite oxide having an average particle size of not less than 10 μm, wherein [20/(specific surface area x average particle size)]=7-9, is used as a positive electrode active material.

Description

492207 i. Description of the invention ([Field of invention]: I The invention relates to non-aqueous electrolyte secondary batteries. More specifically, the invention relates to the improvement of lithium ion secondary batteries. In particular, it is a tool (please read the note on the back first? Please fill in this page again) 3Charge and discharge cycle properties and lithium ion-^, positive electrode active material, positive electrode active material composition for battery safety ability, and have improved discharge cycle properties, low temperature properties and safety [Background of the invention] _ Lithium-ion secondary batteries have excellent electromotive force and battery capacitance, and are more advantageous than nickel-cadmium batteries, etc. due to their high energy density and high voltage. In recent years, lithium At the same time, ion secondary batteries are more attractive, and they are more often used as a driving force for 'portable devices (such as mobile phones and notebook personal computers).' Various studies to provide products with relatively high performance "In detail, these studies focus on the lithium ion secondary battery constituent materials (positive active material, negative active material, Electrolytes, etc.) 1 As far as the positive electrode active materials of ion secondary batteries are concerned, many employees of the Intellectual Property Bureau of the Ministry of Economic Affairs have printed transition metal composite oxides (such as Li-Mn composite oxides) in consumer cooperatives. Materials, Li-Ni-type composite oxides, Li-Co-type composite oxides, etc.) are proposed. Among them, Li_Co-type composite oxides are mainly used because of their chemical stability, easy handling, and manufacturing of high-capacity secondary batteries There are also many suggestions and reports on the further improvement of the properties of Li-Co type composite oxides and finally the use of Li_co type composite oxides as the positive electrode active material of secondary batteries. For example, JP-B_7 -118318 reveals that LiCo02 can improve the discharge capacity of secondary batteries. The LiCo02 is based on the addition of a large amount of lithium compounds and cobalt. The paper size is applicable to China National Standard (CNS) A4 (210 X 297 mm) 1 311440: 207 A7 V. Description of the Invention (2) A compound, a compound obtained by heating these compounds and removing unreacted compounds and lithium carbonate by-products from the reaction product by washing with water. Generally, The positive electrode active material of an ion secondary battery is a layer made of a composition composed of a conductive material and a binder made of an organic polymer (hereinafter also referred to as a positive electrode active material composition). The conductive material can use various graphites. And carbon black. The positive electrode active material is usually used in the form of particles, and each particle is dispersed in the non-conductive adhesive of the composition. When the conductive material does not exist, the particles of the positive electrode active material will be electrically insulated due to the role of the binder. Cancerous, so that the positive electrode active material composition layer (hereinafter also referred to as the positive electrode active material layer) is substantially electrically insulating. The conductive material makes the layer conductive by virtue of its existence between the particles of the positive electrode active material. It is conductive. As a result, the positive electrode active material layer becomes conductive as a whole. As described above, the positive electrode active material is used in a particulate form. When the particle size is too small, during the charging and discharging of the secondary battery, the reactivity sometimes becomes large enough to cause an abnormal battery reaction to a dangerous stage. The present inventors have found that, from the viewpoint of safety of a secondary battery, a preferable average particle size of the positive electrode active material is not less than 10 #m. However, an average particle size of not less than i 0 and m will reduce the conductivity of the positive electrode activity, often resulting in a decrease in charge and discharge cycle properties. As for the negative electrode active material and electrolyte, for example, JP-A_6-368 () 2 reveals the charge and discharge cycle properties of lithium ion secondary batteries. By using a positive electrode active material made of a Li-transition metal composite oxide, A negative electrode active material made of specific green carbon fiber, and selected from the group consisting of ethylene carbonate, propylene carbonate, butene carbonate, butyrolactone, cyclobutane, 3-methylcyclobutane, tetrahydrofuran, 2 · Methyltetrahydrofuran, acetonitrile, dimethoxyacetamidine '(Please read the note on the back? Matters before filling out this page)--Γ-. Mamme «ϋ 1 I HA-» — —Hal I 1 · I aam μη · Mm amt > I Printed by the Consumers ’Cooperative of the Intellectual Property Bureau of the Ministry of Economic Affairs, the paper is printed in accordance with the Chinese National Standard (CNS) A4 (210 X 297 mm) 2 311440 492207 A7 —— —» ^^ ··· — _ 5. Description of the invention (3) -------------- Wear --- (Please read the precautions on the back before filling out this page) Diethoxyethane, dimethylene A mixed solvent of-or more members of the group consisting of maple, dioxane, 4-methyldioxane and diethyl carbonate It can be modified to reveal the charge and discharge cycle properties of the clock ion secondary battery. The positive electrode active material made of w Li_transition metal composite oxide, graphite-type carbon material can be used as negative electrode active material f, and ethyl carbonate. A mixed solvent of methyl methyl ester and dimethyl carbonate is used as an electrolyte, and a mixture of the above agent and ethylene carbonate or propylene carbonate is further modified as an additional ingredient. When you want to add these ingredients, you must pay attention to adding propylene carbonate to the graphite-type carbon material as the negative electrode active material, which will cause the decomposition of the solvent. Therefore, in this case, it is better to use ethylene carbonate; and when When the negative electrode active material is a carbon material other than graphite, it is preferable to use carbonic acid and propyl acetate (see below). As compared with the above-mentioned 'bell ion secondary battery, compared with nickel-cadmium batteries, etc., it has many excellent properties in terms of high energy density, high voltage, and the like. On the other hand, it has a lower unsatisfactory low-temperature property because it produces a lower discharge capacitance and a lower discharge voltage when compared with the case of discharging at room temperature during low-temperature discharge. In particular, at extremely low temperatures of not higher than -2 (rc (and not higher than -35 ° c)), the discharge voltage drops sharply during the initial stage of discharge. In the low-temperature discharge curve [horizontal axis two discharge permittivity, / vertical axis: discharge voltage (V)], the minimum value and the maximum value successively appear in the direction of discharge 'permittivity increase. However, it is not higher than -20. : At extremely low temperatures, the difference between the minimum and maximum values becomes approximately 0.3 (V) to 0.5 (V), and when the permittivity of discharge 1 is 0%, the difference between the minimum and discharge voltage becomes approximately 0 · 5 (V) to 1 · 0 (V), which leads to a sharp drop in the voltage at the beginning of the discharge. In fact, the size of the paper is applicable to the Chinese National Standard (CNS) A4 (210 X 297 mm) 3 311440 A7 B7 5 4. Description of the invention (4) The electric voltage may fall below the stop voltage setting of each device. This makes the device practically inoperable. This low-level, low-level nature problem prevents the battery from being exposed to cold. Application of observation monitors, communication devices, electric vehicles, electric power, and storage devices used in local areas. Some measures to place the battery in a warmer place or apply a heater to prevent the battery temperature from falling below a certain level can make the battery used in the aforementioned equipment, but will increase the cost of the equipment. Therefore, the use of ion secondary batteries The main problem lies in overcoming low temperature properties.-In general, the clock ion secondary battery has a structure in which the positive electrode plate and the negative electrode plate are opposed to each other through a separator, and the electrolyte is filled in the gap between the two electrodes. The positive (negative) electrode is A positive electrode active material layer made of a positive (negative) electrode active material, a conductive material, and a binder is formed on a current collector (such as a metal drop). As described above, the “positive electrode active material and the negative electrode active material are particulates, because The particles contain gaps, which allows the electrolyte to enter the electrode through the gap, causing chemical changes in charging and discharging. The more active chemical changes in the electrode will improve the battery capacitance, permittivity properties, and low temperature properties. By increasing the active material's The particles can get enough space, but the larger particle size reduces the packing density of the active substance and the unit volume. Battery capacitance. Electrolytes that do not show increased viscosity at low temperatures are considered to improve low temperature properties, because Dagger Valley electrolyte penetrates into the electrode at low temperatures without lowering the degree of active material. However, in conventional electrolytes, low viscosity and The high freezing point is closely related. For example, in the components commonly added to the electrolyte, adding a higher amount of dimethyl carbonate will reduce the viscosity of the electrolyte, but also relatively increase the freezing point of the electrolyte. 1 [Overview of the Invention] Please read first Notes on the back t Write this page · Binding Printed by the Intellectual Property Bureau of the Ministry of Economy Employees' Cooperatives Printed on paper This paper applies Chinese National Standard (CNS) A4 (210 X 297 mm) 4 311440 X. Consumption combined with Fi 311440 492207 • * »A7 -__: __ B7 V. Description of the invention (5) Therefore, the object of the present invention is to provide positive electrode activity as a non-aqueous electrolyte secondary battery (especially a lithium ion secondary battery). An improved Li-transition metal composite oxide for substances, which has the ability to improve the cycle characteristics of battery charge and discharge; The Li_ containing transition metal composite oxide as as a positive electrode active material of a lithium ion secondary battery suddenly (the first lithium ion secondary battery) ,. The object of the present invention is also to provide a positive electrode active material composition having improved conductivity, which contains a positive electrode active material (Li-transition metal composite oxide) having an average particle size of not less than 10 // 111. It is preferable for safety and a lithium ion secondary battery (second lithium ion secondary battery) containing the positive electrode active material composition. '' Another object of the present invention is to provide a lithium ion secondary battery (third lithium ion secondary battery) having significantly improved charge and discharge cycle properties due to a combination of a novel negative active material having an ability to improve charge and discharge cycle properties and an electrolyte. battery). Another object of the present invention is to provide a lithium ion secondary battery (fourth lithium ion secondary battery) having sufficiently improved charge and discharge cycle properties, storage properties, and low temperature properties without reducing energy density. Further, the object of the present invention is to provide low-temperature (not higher than -20 ° C, especially not higher than -35 ° C), because the use of a specific electrolyte with a low viscosity, the discharge capacitance and discharge voltage are not reduced, Therefore, a lithium ion secondary battery (fifth lithium ion secondary battery) that does not solidify at low temperature. A further object of the present invention is to provide an extremely low temperature, especially not higher than _2 () t, in the initial stage of discharge, The paper size of the lithium ion secondary electrical clothing whose discharge voltage does not drop sharply is applicable to the Zhongguanjia Standard (CNS) A4 specification (210 X 297). 5 -------------- -Shang -----: ---- Order --------- (Please read the notes on the back before filling this page) 492207 A7

(Sixth lithium-ion secondary battery). To achieve the above objects, the present invention has the following characteristics. (Please read the precautions on S side before filling out this page)

In the first aspect of the present invention, a granular Lb transition metal composite oxide having an average particle size of not less than m is used, in which ⑽ (behind specific surface (X average particle size)) = 7-9 is used as a positive electrode active material In the second aspect of the present invention, a granular Li-transition metal composite oxide having an average particle size of not less than 10 m is used as a positive electrode active material, and a large particle size conductive material is used in parallel. A mixture of a substance and a small particle size conductive substance to improve battery safety and charge-discharge cycle properties. In the second aspect of the present invention, a specific surface area of not more than 200 m2 / g and a lattice plane (d002) are used. Graphitized carbon with an interval of not more than 0.338 nm and a crystallite size in the c-axis direction (Lc) of not less than 30 nm as a negative electrode active material 'and use of ethylene carbonate, acrylic acid, acrylic acid, and carbonic acid Methyl vinegar and an electrolyte mixed solvent selected from at least one member of the group consisting of diethyl carbonate and ethyl methyl carbonate to improve the charge-discharge cycle property. The Consumer Cooperative of the Intellectual Property Bureau of the Ministry of Economic Affairs printed the first Four states , Use a granular Li-transition metal composite oxide with an average particle size of not less than i 0V m, where [20 / (specific surface area x average particle size)] = 7-9 as a positive electrode active material; use a large particle size conductive material As a conductive material, a mixture with a small-grained conductive material; a graphitization having a specific surface area not greater than 2.0 m2 / g, a lattice plane (d002) interval not greater than 0.3380 nm, and a crystallite size in the c-axis direction (Lc) of not less than 30 nm Carbon is used as the negative electrode active material; and the paper size including ethylene carbonate, propylene carbonate, dimethyl carbonate and a group selected from the group consisting of diethyl carbonate and ethyl methyl carbonate is applicable to China National Standard (CNS) A4 Specifications (210 X 297 mm) 6 311440 4 ^ 2207

5. Description of the invention (7) At least one of the electrolyte mixed solvents is used to improve the charge-discharge cycle properties, storage properties and low temperature properties. Printed by the Consumer Cooperative of the Intellectual Property Bureau of the Ministry of Economic Affairs in the fifth aspect of the present invention, the use of vinegar carbonate including a ratio of 4% by volume to 10% by volume, and a ratio of 1Q% by volume to 17% by volume Propylene carbonate, dimethyl carbonate in a proportion of 30% to 40% by volume, and at least one member selected from the group consisting of ethyl ethyl carbonate and ethyl methyl carbonate in a ratio of 40% to 50% by volume The electrolyte mixed solvent I 'is used to suppress the decrease in discharge capacitance and discharge voltage when the temperature is below -20 ° C or below -20 ° C. In the sixth aspect of the present invention, the lithium ion secondary battery at the time of -200 ° C discharge shows 'backslash' discharge curve with no minimum value, ▲ or (ii) increases in discharge permittivity The discharge curve showing the minimum and maximum values in the direction, or (iii) the discharge curve showing the first maximum value, the minimum value, and the second maximum value in the direction of the increase in discharge permittivity. These three curves are displayed at 20 ° C on the horizontal axis. The discharge permittivity calculated as the discharge capacitance (loo%) of the discharge at 1C is plotted against the coordinates of the discharge voltage displayed on the vertical age axis. In the case of curve (ii), the difference between the minimum value and the maximum value is not different. Greater than 〇 丨 V, and when the discharge capacity is 0%, the difference between the minimum value and the discharge voltage is not greater than 0.3V, and, in the case of curve (iii), the minimum value and the second maximum The difference between the values is not too large. When the discharge capacitance is 0%, the difference between the minimum value and the discharge voltage is not greater than 0.3V. When the battery is discharged at 1C at -20 ° C, the discharge capacitance shows a lot. 60% of discharge capacitance when discharged at 20 ° C. [Brief Description of the Drawings] Figure 1 shows the implementation of the present invention through one of the discharge curves of an ion secondary battery ------------- Shang ----- r --- Order ---- ----- Line (Please read the note on the back? Matters before filling out this page) This paper size applies to China National Standard (CNS) A4 (210 X 297 mm) 7 311440 m 207 A7 V. Description of the invention ( 8) Examples. Fig. 2 shows another embodiment of the discharge curve of the lithium ion secondary battery of the present invention. Fig. 3 shows another embodiment of a discharge curve of a clock ion secondary battery according to the present invention. [Detailed Description of the Invention] The present invention is described in detail below to make it obvious. The Li-transition metal composite oxide of the present invention is a particulate material, and its specific surface area (mVg) and average particle size satisfy the formula by the product of 岣: 7 $ [20 / (specific surface area × average particle size 9) Positive electrode active material of secondary battery (especially clock ion secondary battery). The first lithium ion secondary battery of the flute ^ ^ ^ of the present invention contains this Li-transition metal composite oxide as a positive electrode active material. Specific surface area and average particle size A π transition metal composite oxide having a specific relationship as shown in formula ⑴ can be exemplified by the following formula ⑺ or (3):

LiAM1-xMex〇2 (2) where M is a transition metal such as c0, Ni, Mn, vue, etc., and

LiAM2-xMex〇4 (3) In the formula, M is a furnace gold such as Mn, Fe, Ni, etc. In the formula, Me is a periodic table ... Λ degree metal. Yu Shiji and (3)

Fe, C. Elements of group M, such as Zr, V, Cr, M. ,

Fe, Co, Mn, Ni, etc.

Ge 'Pb > Sn. Sb ^, elements of the group, for example, B and Ab. Two Me and 1 ^ are different elements and Me may be composed of two or more elements. 〖Formula (2) Let A be from 0.05 to ---- 15, preferably 0.1 to 1.1, formula (3) This paper size is applicable to China ^^^^ 7 ¥ 17 8 (Please read the Note: Please fill in this page again) 311440 492207 A7 ------ -B7 ___ V. In the description of the invention (9), A is 0.05 to 2.5, preferably 0.5 to 1.5. X in the formulae (2) and (3) is 0 or 0.01 to 0 5, preferably 0.02 to 0.2. When Me consists of two or more elements, X is the total of the two or more elements

number. Preferred examples of the Li-transition metal composite oxides of formulae (2) and (3) include

Li-Co type composite oxides such as

LiCo02, LiNi02, LiMn02,

LiMn (Bux) Alx〇2, LiMn (1-x) Cox02, LiMn (1-x_Y) AlxCoY02, LiMn204, LiMn2.xC〇x04, LiMn2.xCoxGeY04, LiCo (1.x) Nix02, LiNi (1_x) Aix〇2 , LiCo (i χ) Μηχ〇2, etc., where 〇! ^

X Please read the notes on this page before filling in k and 〇 ", preferably LiCo02, ΕίΜη (1-χ) €; οχ02, LiMn ^ uy) A1xCoy02, LiC〇 (1-x) Nix02, LiCo (1 -X) Mnx02, etc., especially preferred

Order I

LiCo02 o

The Li-transition metal composite oxide needs to satisfy the above formula (1), because when [20 / (specific surface area x average particle size)] is less than 7 or greater than 9, the resistance of the positive electrode active material itself increases, thereby reducing the charging of the secondary battery. And the nature of the discharge cycle, it also adversely affects the low-temperature properties and storage properties of lithium ion secondary batteries. Printed by the Ministry of Economic Affairs and the Ministry of Economic Affairs' "Hui-Finance" " Bureau of Consumer and Consumer Affairs

The Li-transition metal composite oxide preferably has an average particle size of 10 / ζιη to 25 am, and particularly preferably 17 to 23 / z m. When the average particle size is less than i 〇 // m, ′ tends to cause abnormal battery reactions and is less safe; when the average particle size exceeds 25, the resistance becomes higher, and the energy density per unit volume of the lithium ion secondary battery tends to decrease.

The Li-transition metal composite oxide preferably has a specific surface area of 0.001 to 0.3 m2 / g, and particularly preferably 0.15 m2 / g to 0.25 m2 / g. Dangbi This paper size applies Chinese National Standard (CNS) A4 (210 X 297 public love) 9 311440 A7

492207 V. Description of the invention (When the surface area is less than 0.1 m2 / g, the resistance increases and the charge and discharge capacitance and permittivity properties tend to decrease; when the specific surface area exceeds 0 3 m2 / g, it is easy to separate oxygen from the active material, so May compromise safety.

The average particle size of the Li-transition metal composite oxide was measured by the following method. First, the target particles to be measured are cast in an organic liquid (such as water, ethanol, etc.), and subjected to ultrasonic treatment at about 35 kHz to 40 kHz to disperse them. The content of the particles is that after the dispersion treatment, the laser light transmittance (light output / light input) of the dispersion is 70% to 95%. Next, the dispersion is applied to a microtrack particie size analyzer, and the particle size (Dl, D2, D3, ···) and the number of particles of each size can be measured based on the diffusion of the laser beam. (N1, N2, N3 ...). The particle size analyzer calculates the particle size distribution of a group of spherical particles having the theoretical intensity distribution closest to the laser beam diffusion intensity distribution measured by the detector. That is, it is assumed that the particle has a circular cross section with the same area as the projection image obtained by irradiating the laser beam, and the diameter of the cross section circle is taken as the particle size. Using the particle size (D) of each particle obtained above and the number of particles (N) with various particle sizes, the following formula (4) is used to calculate the average particle size (/ zm): Average particle size (in m) = (Σ ND3 / Σ N) 1 / 3 (4)

Li_transition metal composite oxide has a specific surface area measured by a gas phase adsorption method (single point method), in which nitrogen is an adsorbate, and the adsorption method is described in Material Chemistry of Fine Particles (yasuo Arai, first edition, 9th impression, Baifukan (Tokyo) pp.178-184 (1995)-For example, Li_transition metal composite oxide can be given by the following methods. Please read the precautions on the back before filling in this page. · Printed by the Consumers' Cooperative of the Intellectual Property Bureau of the Ministry of Economic Affairs, the paper size applies the Chinese National Standard (CNS) A4 specification (210 X 297 mm) 10 311440 492207 Printed by A7 of the Consumers ’Cooperative of the Intellectual Property Bureau of the Ministry of Economic Affairs One method involves mixing the starting lithium compound with the desired transition metal compound so that the atomic ratio of the transition metal to warp is 1 · 1 to 〇8 · 1,-·· in air, at a temperature of 700 ° C to 1200 ° C, heating the mixture for 3 to 50 hours to make the reaction occur, crush the reaction product into particles, and obtain an average particle yield of less than 10 # m and satisfy the above formula A different method further includes, for example, about 400 ° C to 750 ° C, specifically 450C to 700C, 'heating the above-mentioned pulverized particles for about hours> to 50 hours, particularly about 1 hour to 20 hours. It is preferred to have an average particle size of 10 m to 25 // m. When subjected to such a heat treatment, the specific surface area will be reduced only if the particle size does not change. As a result, Li- which satisfies the above formulas can be easily obtained. Transition metal composite oxide. ▲ The pulverized particles are heat treated in any atmosphere [may be in the atmosphere or under an inert gas (such as gas, rat gas). However, when carbon dioxide gas is present in this atmosphere Lithium carbonate will be generated to increase the content of impurities. Therefore, the heat treatment is preferably performed in an atmosphere in which the partial pressure of carbonic acid gas is not higher than about ► mmHg. Specific examples of the above-mentioned starting lithium compounds are lithium oxide, lithium hydroxide, • Halogenation, nitric acid, oxalic acid, carbonic acid and mixtures thereof. Examples of transition metals and compounds include transition metal oxides, transition metal hydroxides, transition metal oxides, Transition metal nitrates, transition metal oxalates, transition metal carbonates, and mixtures thereof. When the desired composite oxide contains the aforementioned formulae (2) and (3), the substituted element (Me) is used in lithium compounds. Add the required amount of the substituted element (Me) compound 0 to the mixture with the transition metal 1 metal compound ^ -----: ---- t --------- line f, please read the back Note: Please fill in this page again) This paper size is in accordance with Chinese National Standard (CNS) A4 specification (210 X 297 mm) 11 311440 492207 Printed by Employee Consumer Cooperative of Intellectual Property Bureau of Ministry of Economic Affairs 12 A7 V. Description of the invention (in the present invention 'A composition (a positive electrode active material composition) containing a Li-transition metal composite oxide as a positive electrode active material, a conductive material, and a binder is prepared, and this composition is usually formed into a layer to obtain a positive electrode active material layer. Examples of the binder include polytetrafluoroethylene, polyvinylidene fluoride, polyethylene, ethylene-propylene-diene type polymers, and the like. The conductive substance may be natural or artificial graphite such as fibrous graphite, flaky graphite, spherical graphite, conductive carbon black, and the like. The amount of the binder used per 100 parts by weight of the Li-transition metal composite oxide is about 1 to 10 parts by weight, preferably 2 to 5 parts by weight. Per 100 parts by weight

The amount of the conductive substance used in the Li-transition metal composite oxide is about 3 to 15 parts by weight, preferably 4 to 10 parts by weight. The positive electrode active material layer is usually bonded (adhered) to the current collector to form a positive electrode. The positive electrode current collector used with the positive electrode active material layer is preferably a foil or a porous foil of a conductive metal (such as aluminum, aluminum alloy, titanium, etc.), and its thickness is about 10 to 100 m, particularly It is about 15 to 50 μm, or a thickness of about 25 to 300 #m, especially about 1 to 1 porous metal plate (with 1 ^ 11 cores (1111 to 31), etc.) adheres to the positive current The amount of the positive electrode active material composition on one surface of the collector is usually 5 to 40 mg / cm2, preferably 10 to 30 mg / cm2. The lithium-transition metal composite oxide is used as the positive electrode active material to constitute lithium. In an ion secondary battery, the negative electrode active material is preferably graphite such as various types, natural graphite and artificial graphite (such as fibrous graphite, flaky graphite, spherical graphite, etc.) or graphite-type carbon materials (such as graphitized carbon). The substance is mixed with a binder to form a composition, and then it is formed into a negative electrode active material layer. Examples of the binder include those previously exemplified in the positive electrode active material layer. If necessary, a conductive substance such as carbon black (especially acetylene) may be added. Carbon black) W _ 家 鲜 (CNS) T4_Specifications ⑽ ^ 311440 — 17% —IIJIIIII — — — — — — — — — I — «— I! — —! — — (Please read the note on the back first (Please fill in this page for matters) 492207 A7 B7 V. Description of the invention ((Please read the note on the back? Matters before filling out this page), etc. The anode active material layer is usually bonded (adhered) to the current collector to form the I pole. The anode current collector used with the anode active material layer is preferably a foil or porous foil of a conductive metal such as steel, nickel, silver, sus, etc., and has a thickness of about 5 to 100 vm, especially about 8 to 5 〇In m, or a thickness of about 20 to 3 00 " m, especially about 2S to 100 " porous metal plate electrolyte of melons can be obtained by dissolving a salt in an organic solvent, examples of the salt include

LiC104, LiBF4, LiPF6, LiAsF6, LiAlCl4, Li (CF3S02) 2N, etc. use one or more kinds of mixtures thereof. Examples of the above-mentioned organic solvents include ethylene carbonate, propylene carbonate, dimethyl carbonate, diethyl carbonate, ethyl methyl carbonate, dimethyl methylene maple, cyclobutadiene, butyrolactone, U-methoxyethyl Alkanes, N, N-dimethylformamidine, tetrahydrofuran, diisocene-alkane, 2-methyltetrahydrofuran, diethyl ether, etc. are used in a mixture of one or more of them. The concentration of the above salt in the electrolyte is about 0.01 to 3 mO1 / L. Printed by the Consumers' Cooperative of the Intellectual Property Bureau of the Ministry of Economic Affairs, the positive electrode active material composition of the present invention contains at least L "transition metal composite oxide with an average particle size of not less than 10 / zm as a positive scandium active material, ► particle size of not less than 3Mm (larger size ) Conductive material particles, and conductive material particles with a particle size of not more than 2 m (smaller size) (first specific example); or Li_transition metal composite oxides with an average particle size of not less than 10% Positive electrode active material, conductive material particles with a particle size of not less than 3 / zm (larger size), particles, and straight diameters (smaller sizes) of fibers having an aspect ratio of 3 or more and not more than 2 / zm Conductive substance fiber (second specific example). The second ion secondary battery of the present invention contains one of these two positive electrode active material compositions. The positive electrode active material in this composition, that is, the \ Li_transition metal composite oxide, is preferably the one represented by the aforementioned formulas (3) and (4), particularly preferably the Lic00 wood paper size is applicable to Chinese national standards (CNS) A4 size (210 X 297 mm) ----------------- 13 311440 492207 A7 Printed by the Consumer Cooperative of Intellectual Property Bureau of the Ministry of Economic Affairs

492207 A7 B7 V. Description of the invention (15) The safety of the positive electrode active material composition for lithium ion secondary batteries and improved charge and discharge cycle properties. To achieve this, the Li_transition metal composite oxide (positive electrode active material) has an average particle size of not less than 10 // m. (Please read the note on the back? Matters before filling out this page} * When the average particle size is too large, the Li-transition metal composite oxide itself has a large resistance. Even if a conductive carbon material is added, the positive electrode active material cannot be made. The resistance of the composition is reduced. Therefore, the average particle size is preferably 10 / zm to 30 / zm, particularly preferably 10 / zm to 25 / im °. The average particle size of the Li-transition metal composite oxide is determined by the method described in 1. When the relationship between the specific surface area and the average particle size satisfies the aforementioned formula (1), better results can be produced. In the first specific example of the positive electrode active material composition, a granular conductive material having a particle size of not less than 3 Wm is used. (Hereinafter referred to as the first conductive substance)-and a granular conductive substance having a particle size of not more than 2 m (hereinafter referred to as the second conductive substance); in the second specific example, the aforementioned first conductive substance is used and has 3 or An aspect ratio (fiber length / fiber diameter) of 3 or more and a fibrous conductive material (hereinafter referred to as a third conductive material) having a fiber diameter of not more than. The granular shape used herein means, but is not limited to, scaly, spherical, Pseudoball Bump-like, whisker-like, etc. Printed by the Consumer Cooperatives of the Intellectual Property Bureau of the Ministry of Economic Affairs as a conventional conductive substance, carbon can be used as the first conductive substance. For example, artificial or natural graphite can be used, and carbon black such as acetylene carbon. Black, oil furnace black, superconducting furnace black, etc. To achieve improved cycle properties, it is better to use graphite among these carbon materials, especially the lattice plane (dOO2) interval is not greater than 0.34㈣ and c _Graphic carbon with a crystallite size in the axial direction (Lc) of not less than 10. 1 The above lattice plane (d002) interval and the crystallite size in the c-axis direction (Lc) can be used on a paper scale. (CNS) A4 specification (210 X 297) 15 311440 492207 A7 V. Description of the invention (16) Measured in accordance with the method of the Japan Society for the Promotion 〇f science Method detailed below. (Please read the precautions on the back before filling this page.) In a Malex mortar, pulverize the high-purity silicon used as an X-ray standard substance to a particle size of no more than 325 standard mesh. This standard substance and the test to be determined kind( Inked carbon) was mixed in a mason mortar (graphitized carbon: 100 wt%, standard material: 10 wt%) to obtain a sample for X-ray measurement. This X-ray sample was uniformly filled in X-ray diffraction. Device (RINT2000, manufactured by RIGAKlJ ELECITKIC: CORPORATION, X-ray source: CuK α-ray) in a sample plate. The voltage applied to the x-ray tube is 40kv, the applied current is 50 mA, and the scanning range is 20 = 23 5 Measure the peak of carbon 0.02 and the peak of m of the standard material under conditions such as 29 and scanning speed 025 ° / min. The graphitization degree calculation software provided in the above-mentioned X-ray diffraction device was used to calculate the lattice plane (dOO2) interval and the crystallographic direction (Lc) crystallite size from the positions of the obtained peaks and their half-width peaks. Printed by the Consumer Cooperatives of the Intellectual Property Bureau of the Ministry of Economic Affairs. The conductive material is used to improve the electrical connection between the positive electrode active material particles. It should have a certain size to achieve the intended electrical connection. If the particle size is too large, the closest packing of the positive electrode active material is prevented '. Therefore, it is preferable to use particles having a particle size of 25 // m. In addition, it is better to use particles whose specific surface area is not greater than mVg, especially from i mVg to 10m2 / g. Assuming that the particles constituting the first conductive substance are spherical, the particle size of the first conductive substance means the diameter of its cross-section circle, and it is measured using a micro-orbit particle size analyzer in the case of the aforementioned Li · transition metal composite oxide. As for the second conductive material, the same as the first 1 spear conductive material, human S or natural graphite can be used, and 4 black cases, two carbon blacks, oil furnace black, and super conductive; this paper size applies Chinese National Standards (CNS) A4 Regulations' (21 (^ 297 公 | ^ 16 311440 Printed by the Consumer Cooperatives of the Intellectual Property Bureau of the Ministry of Economic Affairs, 5. Description of the Invention (17) Black, etc.) The first conductive substance is used to make the surface of the positive electrode active material particles The size of the conductive seat is too large to prevent this effect. Therefore, it is particularly preferable to use particles with a particle size of not more than 1 vm. In addition, use a specific surface area of not less than; 10 m2 / g ', especially not less than 15 m2 / g Assume that the particles constituting the second conductive material are spherical. The particle size of the second conductive material means the diameter of its cross-section circle, which is measured using a micro particle size analyzer. When the particle size is less than 1 V m, Due to the dispersion, the particles tend to agglomerate. When the particle size is less than lem, an electron microscope is preferred. For details, set the magnification to a value containing at least 20 particles in the visual field, and 'take an electron micrograph. Then, calculate The area of the image of each particle on the sheet. Calculate the diameter of a circle with the same area from the area of the difference. Assuming that the particles constituting the first conductive substance are spheres with a cross-section circle of this diameter, this diameter is regarded as the second conductive substance. The specific area of the first conductive material and the second conductive material is measured by the gas phase adsorption method (single-point method) using nitrogen as an adsorbent in the same manner as the specific surface area of the transition metal composite oxide 1 described above. As for the third conductive substance, various carbon fibers can be used. In particular, carbon fibers prepared by a vapor phase growth method, graphitized carbon fibers such as mesophase, graphitized carbon, etc. The broken fibers can be linear or crimped. ^ The third conductive material, like the second conductive material, is used to make the surface of the positive electrode active material particles conductive, and the size is too large to prevent this effect. Therefore, the use of 10 to 50 aspect ratio (fiber length / fiber Diameter) is better. In addition, the use of particles with a fiber diameter of no more than 1 // m is ^ -----: ---- ^ --------- ^ f Please read the back Note Please fill in this page for more details) This paper size is in accordance with Chinese National Standard (CNS) A4 (210 X 297 mm) 17 311440 492207 A7 ___ B7__ _ V. The invention description (1S) is good. (Please read the note on the back first? Please fill in this page again) Like the second conductive material whose particle size is not larger, the aspect ratio and fiber diameter of the third conductive material are measured using an electron microscope. In particular, set the magnification to a field of view containing at least 20 fibers Value, and take an electron micrograph. Next, use a caliper to measure the fiber diameter and fiber length of each fiber in the photo. The fiber length of the linear fiber is the shortest distance from one end to the other end of the fiber; the fiber length of the crimped fiber The distance between two optional and furthest points on the fiber. When the usage ratio of the first conductive material, the second conductive material, or the third conductive material is too unbalanced (too large or too small), the effect of using the aforementioned conductive material with a larger size and the conductive material with a smaller size tends to reduce. The amount of the second conductive substance or the third conductive substance used per 100 parts by weight of the first conductive substance is preferably 1 part by weight to 200 parts by weight. To achieve better improved conductivity and safety, it is preferably 5 parts by weight to 100 parts by weight, and particularly preferably 10 to 50 parts by weight. The total amount of conductive materials used in 100 parts by weight of Li-transition metal composite oxides printed by the Consumer Affairs Agency of the Intellectual Property Office of the Ministry of Economic Affairs is, for example, about 3 parts by weight to 15 parts by weight. In the present invention, since two conductive materials of different sizes are used, the amount of the ethylene oxide transition metal composite oxide per 100 parts by weight is less than the conventional amount, for example, 3 to 10 parts by weight, and may be Provides sufficient energization and conductive effect. Therefore, the amount of the Li-transition metal composite oxide is increased, and as a result, the battery capacity S can be increased. The binder of the positive electrode active material composition may be polyfluorinated tetrafluoroethylene, polyvinylidene fluoride, polyethylene, ethylene-propylene-diene polymer 5 or the like. The amount of the binder used per 100,000 parts by weight of the positive electrode active material composition is 1 part by weight to 20. This paper size is applicable to National Standard T (CNS) A4 (21Q x 297). 18 311440 492207 A7

5. Description of the invention (19) Part by weight 'is preferably 1 part by weight to 10 parts by weight. "Economic and intellectual property" Bureau ’s consumer cooperatives printed on other components of the battery, Gamma, j, together with the composition of the positive electrode active material constitutes the positive current of the positive electrode, micrograms; carcass negative active material, negative current collector, Electrolytes (organic solvents that make up the electrolyte of You Banyin) and the like are preferably exemplified by the aforementioned FA-Ming (Li_transition metal composite oxide having a special relationship between particle size and specific surface area). Adhesives to the positive current collector The amount of the positive electrode active material composition on one surface is usually 5 to 4q] The main 40 mg / cm2, preferably 10 to 30 mg / cm2. The third ion secondary battery of the present invention includes Graphitized carbon greater than 2.0mVg, lattice plane (d002) interval not greater than 0.338nm & c-axis direction (Lc) crystallite size not less than 30 nm, as a negative electrode active material, and ethylene carbonate, propylene carbonate, As the electrolyte solvent, dimethyl carbonate and a mixed solvent selected from at least one of diethyl carbonate and ethyl methyl carbonate are used. The graphitized carbon is preferably 0.7 m2 / g to 1.5 m2 / g. Surface area, lattice plane (d002) interval from 0.3350 nm to 0.3370 nm, and c-axis direction (Lc) crystallite size from 40 nm to 80 nm. Specific negative electrode active material and electrolyte combination, even if the electrolyte mixed solvent contains EMC, DMC And PC, also provide excellent discharge cycle properties, without the decomposition of mixed solvents as described in JP-A-7-14607. When graphitized carbon has a specific surface area greater than 2.0 m2 / g, pc is easily decomposed during charging and Decrease the capacitance. When the lattice plane (d002) interval is greater than 0.33 80 nm or i When the crystal size in the c-axis direction (Lc) is less than 30 nm, the reversibility of the negative active material through the intercalation reaction is insufficient. As a result, ------------- install -----; ---- order --------- line (please read the precautions on the back before filling this page) This paper size applies to China National Standard (CNS) A4 (210 X 297 public love) 19 311440 492207

V. Description of the invention (20) The charge and discharge cycle properties of the battery are reduced. Like ordinary graphite negative electrode active materials, (Please read the precautions on the back before filling this page). The particles constituting the graphitized carbon may be scaly, fibrous, spherical, pseudo-.., ..., particularly in the shape of m-based carbon. However, it is easy to coat the negative electrode with a negative electrode active material composition. From the viewpoint of the orientation of the graphitized carbon after coating, it is preferable to cover the anode current collector and the s, and the graphitized carbon is preferably saccharate. Therefore, it is particularly preferable to use fibrous mesophase graphitized carbon, that is, mesophase graphitized carbon fibers. The mesophase graphitized carbon fiber can be produced by, for example, the following method. First example of the Sake field, firstly, the asphalt, such as petroleum greens and coals, was melted by the dissolving method. In particular, the mesophase containing the mesophase with a proportion of not less than 70% by volume was wet blue and spun into a length of about 20 / zm to 300 zm fiber. At 800. (: To t: carbonize this fiber 'and pulverize it into fibers having an appropriate size such as an average fiber length of about 1 to 100 / zm and an average fiber diameter of about 1 to 131 to 15. At 2500 ° C to 3200 ° c, preferably from 2800c to 3200, plus the consumer cooperative of the Intellectual Property Bureau of the Ministry of Economic Affairs to print the thermally pulverized fiber and graphitize it to obtain mesophase graphitized broken fibers. The good coatability of the negative electrode active material composition on the negative electrode current collector will be mentioned in the text. It is preferable to perform the above pulverization to make the average fiber length from lem to 100 vm, especially from 3 to 111 to 5 ( ^ 111, or even 2 / zm to 25 / zm, and the average fiber diameter is 0.05 to ^ to 15 v❿, especially 疋 1 // m to 1 5 // m, or even 5 // m to 10 to m. Vertical and horizontal The ratio (average fiber length / average fiber diameter) is preferably from 1 to 5. The specific area of graphitized carbon is the same method as the aforementioned method for measuring the specific surface area of Li-Co type composite oxides [the gas phase adsorption method (single point method) of which Nitrogen is used as the paper standard. Applicable to China National Standard (CNS) A4 (210 X 297 public love) 20 311440 Α7 Α7 Printed clothing by the Consumer Cooperative of the Intellectual Property Bureau of the Ministry of Economic Affairs 5. Description of the invention (21) Attachment] to be measured. The lattice plane (d002) interval of graphitized carbon is based on the aforementioned method The electrolyte mixed solvent has an optional mixing ratio, however, it is preferably selected from the group consisting of ethyl carbonate and 25 vol% to 50 vol% (particularly 30 vol% to 35 vol%). At least one member of ethyl methyl carbonate, preferably containing 4 to 20% by volume (particularly 6 to 18% by volume), preferably containing 3 to 17% by volume Gu Ji / (excellently 5% to 15% by volume) propylene carbonate, and preferably contains a content of 40% by volume or more and not more than 60% by volume ❻ '(exclusively 45% to 55% by volume) When the content of ethylene carbonate is less than 4% by volume, a stable film cannot be formed on the surface of the negative electrode; when the amount exceeds 20% by volume, the viscosity of the electrolyte increases, which in turn increases the resistance of the battery. , Reduce the charge and discharge cycle properties When the content of propylene carbonate is less than 3% by volume, the increase in impedance related to the charge and discharge cycle is suppressed to a small degree; and when the amount exceeds 17% by volume >, the electrolyte viscosity increases, which in turn improves the battery The resistance decreases the charge and discharge cycle properties. When the content of dimethyl carbonate is not more than 40% by volume, the viscosity of the electrolyte increases, which in turn increases the battery resistance, reduces the charge and discharge cycle properties; and its amount exceeds 60 At% by volume, the solidification of the electrolyte and the point increase increase the resistance of the battery at low temperatures, reducing the charging and discharging-electricity cycling properties at low temperatures. When the content of ethyl carbonate and / or ethyl methyl carbonate is less than 25% by volume, the freezing point of the electrolyte increases and the resistance of the battery increases at low temperatures, reducing the charge and discharge cycle properties at low temperatures; and the amount exceeds 50% by volume At %%, the viscosity of the electrolyte increases, which increases the resistance of the battery and reduces the paper size. This paper applies the Chinese National Standard (CNS) A4 specification (210 X 297 mm). -----; ---- Order ---- ----- Line (Please read the note on the back? Matters before filling this page) 21 311440 492207 A7 V. Description of the invention (22 Charging and discharging cycle properties (Please read the note on the back? Matters before filling out this page) The negative electrode active material is mixed with a binder to form a composition, and then it is formed into a negative electrode active material layer. Examples of the binder include polytetrafluoroethylene, polyvinylidene fluoride, polyethylene, ethylene-propylene-diene type polymers, etc. Required In this case, a conductive material such as carbon black may be added. The amount of the negative electrode active material is 80 to 96 parts by weight, preferably 90 to 95 parts by weight, per 100 parts by weight of the total amount of the negative electrode active material and the binder. Negative current collector is better A foil or porous foil that is a conductive metal (such as copper, nickel, silver, sus, etc.) and has a thickness of about 5 to 100 / zm, especially about 8 to 50 m, or about 20 to 30 〇 / zm, especially a porous metal plate of about 25 to 100 // m, etc. The amount of the anode active material composition adhered to one surface of the anode current collector is usually 3 to 20 mg / cm2, preferably 5 to 15 mg / cm2. The electrolyte contains the above mixed solvent and one or more u salts dissolved therein

For example LiC104, LiBF4, LiPF6, LiAsF6, LiAlCl4, U (CF3S02) 2N

Wait. The Li salt concentration of the electrolyte is usually about 0 mO1 / L to 2 mO1 / L, and from the viewpoint of charge and discharge cycle properties, it is preferably about 0.5 mOl / L to 1.8 mol / L. L 'is particularly preferably about 0.8 mOi / L to 1.5 mol / L. Printed by the Consumer Cooperative of the Intellectual Property Bureau of the Ministry of Economic Affairs. The positive electrode active material is composed of a Li-transition metal composite oxide. The composite oxide is preferably a composition represented by the above formulas (3) and (4). Particularly preferred is

LiCo02 or LiACo1-xMex〇2 (wherein a, X and element Me are as defined above) ', and its average particle size is preferably not less than 10 / zm. The binder, conductive material and positive current collector of the positive electrode active material layer are those mentioned in the aforementioned Li-transition metal composite oxide. 1 The fourth lithium-ion secondary battery of the present invention is the above-mentioned transition metal complex standard (CNS) A4 specification 29 x 29 22 311440 a intellectual property of the Ministry of Economic Affairs, printed by the Bureau of Consumer Cooperatives 492207 A7- ---- B7 _ 5. Description of the invention (23) A combination of a composite oxide, a positive electrode active material composition, and a third lithium ion secondary battery. In detail, the system includes the following components: • Positive electrode active material: granular Li-transition # metal composite oxide with an average particle size of not less than 10 # m, [2〇 / (specific surface area X average particle size)] = 7-9 ;-• Conductive substance: a mixture of granular conductive substance having a particle size of not less than 3 / zm and a granular conductive substance having a particle size of not less than 2 # m, or a granular conductive substance having a particle size of not less than 3 / zm and having a particle size of 3 or more Aspect ratio and small [mixture of fibrous conductive materials with a fiber diameter of less than 2 m; • Negative electrode active material • Specific surface area not greater than 2.0 m2 / g, lattice plane spacing not greater than 0.3 380 nm, and c-axis Graphitized carbon with a crystallite size of not less than 30 nm in the direction (Lc);-• Electrolyte mixed solvent: at least one selected from the group consisting of diethyl carbonate and ethyl methyl carbonate, ethylene carbonate, propylene carbonate, and dimethyl carbonate Mixed solvents. Each of these constituent materials [Li-transition metal composite oxide (positive electrode active material), positive electrode active material composition, negative electrode active material, and electrolyte] is as described above. Other components of the battery, such as the positive current collector, the negative active material composition (negative active material layer), and the negative current collector, may be the same as those mentioned in the foregoing description. The lithium ion secondary battery having this composition can provide extremely excellent battery properties due to the synergistic effect and the effects of the foregoing three properties. That is, the improved charge and discharge cycle properties extend the life of the battery; the improved storage properties suppress the deterioration of properties in conventional ion secondary batteries due to serious problems caused by full charging when left to rest; and the low temperature properties can be improved. ------------- install ----- r --- order --------- line (please read the precautions on the back before filling this page) Applicable to China National Standard (CNS) A4 specification (210 X 297 public love) 23 311440 492207 A7 B7 V. Description of the invention (24) The usage ratio of the fifth clock ion secondary battery of the present invention is from vol% to 50 gv /. (Preferably 42 vol% to 48 vol%) at least one selected from the group consisting of diethyl carbonate and ethyl formazan carbonate in a ratio of 4 vol% to 10 vol% (preferably 6 vol% to 9 vol%) ) Of ethylene carbonate vinegar, the ratio is 10 reams /. Propylene carbonate to 17% by volume (preferably vol% to 14% by volume) and dimethyl carbonate having a ratio of 3G vol% to 4G vol% (preferably 32 vol% to vol%) as the electrolyte solvent . The electrolyte therefore has a low viscosity and does not solidify at low temperatures. When the ratio of at least -members selected from the group consisting of diethyl carbonate and ethyl f carbonate is less than 40% by volume, the electrolyte is solidified at low temperature, and chain ions cannot move, so the low-temperature properties cannot be improved; and the amount exceeds 50% by volume At this time, the electrolytic = viscosity is high, and as a result, the ion conductivity becomes low, and the low temperature properties cannot be improved. When the mixing ratio of ethylene carbonate is less than 4% by volume, the lithium salt is not sufficiently dissociated, and the ion conductivity becomes low to improve the low-temperature properties. When the amount exceeds ΙΟ ％ by volume, the electrolyte has a high viscosity, resulting in low ion conductivity. 'It is also impossible to improve low temperature properties. When the content of propylene carbonate is less than 10% by volume, the lithium salt is not sufficiently dissociated 'and the ionic conductivity becomes low to improve low-temperature properties; however, the amount exceeds 17% by volume. At 0 / ', the electrolyte has a high viscosity, and as a result, the ion conductivity becomes low, and the low-temperature properties cannot be improved. When the content of dimethyl carbonate is less than %% by volume, the electrolyte has a high viscosity. As a result, the ion conductivity becomes low and the low-temperature properties cannot be improved. When the amount exceeds 40% by volume, the electrolyte solidifies at low temperatures and lithium ions cannot move, so Unable to improve low temperature properties. The lithium salt dissolved in the electrolyte may be, for example, / Licl〇4, uBF4, LiPF6, UAsF6, LiAlCl4 'Li (CF3S〇2) 2N, etc., and it can be used alone. The paper size is applicable to the Chinese National Standard (CNS) A4 specification ( (210 X 297 mm) 311440 Please read the notes on the back before filling out this page. Ordered by the Intellectual Property Bureau of the Ministry of Economic Affairs, Consumer Consumption Cooperative 24 492207 A7

Printed by the Consumer Cooperatives of the Intellectual Property Bureau of the Ministry of Economy _Axial direction (Lc) crystallite size is not less than a fine (preferably 40 nm to 70 ° C) graphitized carbon. Examples of these graphitized carbons include mesophase graphitized carbons. In preferred specific examples, the Using the negative electrode active material of the aforementioned third ion secondary battery, the result is that the decomposition reaction of acrylic acid vinegar during charging can be sufficiently suppressed, and the battery capacitance is stable; in addition, the increase in the negative electrode voltage can be sufficiently suppressed and the battery The average discharge potential is stable. The shape of the negative electrode active material particles is not particularly limited and may be scaly, fibrous, spherical, quasi-spherical, bulky, or similar. 2. When the negative electrode active material is graphitized carbon, current flows from the negative electrode. From the standpoint of easy coating and particle orientation of the collector (the orientation is favorable for lithium absorption and release), 'particles are preferably fibrous. Therefore,' the best graphitized carbon is a fibrous mesophase graphitized carbon, also Mesophase graphitized carbon fiber. The method for manufacturing mesophase graphitized carbon fiber is as described above. In order to make the negative electrode active material layer meet the above-mentioned specific filling rate, the carbonized fiber is pulverized so that the average fiber length is 1 / ^ to 100 # m, especially It is 3 / ^ to 5 (^ m, more preferably 2 fm to 25 to m), and the average fiber diameter is 0 ##, especially 疋 to 15em, and more preferably 5 // 111 to 10 # m. Vertical and horizontal The ratio (average fiber length / average fiber diameter) is preferably from 丨 to 5. The specific surface area of the above graphitized carbon, the lattice plane spacing, and the c-axis direction (Lc) crystallite size are determined by the same method as previously described The binder used to form the negative electrode active material layer 1 of the lithium ion secondary battery and the above-mentioned phase 1¾. The amount of the binder is 4 to 20 weight percent per 100 parts by weight of the active material, preferably 5 to 10 weight parts. For the negative electrode active material layer, t paper size & τ national national standard (CNS) A4 regulations each (21G x 297) ^ · • I --- J — — — — — —-. II 丨 l · I 1 -1 Order: ------------, (Please read the notes on the back before filling in this page) '26 311440 492207 (27,., Conductive materials are not particularly required, but carbon black (especially acetylene carbon black) can be added if necessary. When conductive materials are used, the amount is from 0.1 to 10 per 100 parts by weight of active material Part by weight, preferably from 0 to 5 parts by weight. The negative electrode collector is preferably a foil or porous sheet of a conductive metal (such as steel, nickel, silver, sus, etc.), and its thickness is about 5 to 100 / zm, particularly about 8 to 50 # m, or a porous metal plate having a thickness of about 20 to 300 μm, especially about 25 to m. The amount of the negative electrode active material composition adhered to one surface of the negative electrode current collector is usually 3 to 20 mg / cm2, preferably 5 to 15 mg / cm2. The positive electrode active material printed by the Consumer Cooperative of the Intellectual Property Bureau of the Ministry of Economic Affairs is composed of a Li-transition metal composite oxide. The composite oxide preferably has a composition represented by the foregoing formulas (3) and (4), and particularly preferably LiCo 02 and LiAC 02-xMex 02 (wherein A, χ, and element Me * are defined above) 'their average particle sizes are preferably not less than 10 / zm. The product of the specific surface area of the particles and the average particle size preferably satisfies the aforementioned formula to comply with the filling rate of the aforementioned positive electrode active material layer. The binder, the conductive material, and the positive electrode current collector of the positive electrode active material layer are preferably those mentioned in the aforementioned Li-transition metal composite oxide. The amount of the binder is 2 to 8 parts by weight, preferably 3 to 5 parts by weight, relative to the active material (per 100 parts by weight). The amount of the conductive material is 4 to 10 parts by weight, preferably 6 to 8 parts by weight per 100 parts by weight of the active material. The sixth lithium ion secondary battery of the present invention is a combination of the aforementioned u_transition metal composite oxide and the aforementioned positive electrode active material composition, and includes the following components: 1. Positive electrode active material: the product of the specific surface area (mvg) and the average particle size The dimensions of the building block paper are in accordance with Chinese National Standard (CNS) A4 (210 X 297 public love) 27 311440 492207 V. Description of the invention (28 Li-transition metal composite oxidation that satisfies the above formula (1) and has an average particle size of not less than 10V m Particles; • conductive material of the positive electrode: a granular conductive material having a particle size of not less than 3 m and (please read the precautions on the back before filling this page) a mixture of granular conductive material having a particle size of not more than 2 / zm, or a particle size A mixture of a granular conductive material not less than 3 // m and a fibrous conductive material having an aspect ratio of 3 or more and a fiber diameter not greater than 2 ^ m. These Li-transition metal composite oxides and the conductive material of the positive electrode All are as described above. Other constituent materials, such as a positive current collector, a negative electrode (a negative active material composition, a negative current collector), etc. may be mentioned above. Figures 1 to 3 The discharge curve of the lithium ion secondary battery of the present invention is shown, wherein the horizontal axis shows the discharge permittivity (%), and the vertical axis shows the discharge voltage (V). 'Each discharge curve is obtained at 1C discharge at -20 ° C. Discharge permittivity (%) Is calculated based on 100% discharge capacitance at 1 ° C discharge at 20 ° C, and displays the ratio to the discharge capacitance. When the cut-off voltage is set during discharge, the discharge permittivity is relative to the cut-off The discharge capacitance at the time of voltage is calculated. In Figures 1 to 3, VF is the stop voltage. Printed by the Consumer Cooperative of the Intellectual Property Bureau of the Ministry of Economic Affairs. Figure 1. The discharge curve is a sloped curve with no minimum value. In the early stage, the radical drop of the voltage is suppressed. 图 中 2, the discharge curve contains the minimum and maximum values in the direction of the increase in discharge permittivity, and the voltage drop occurs in the early stage of the discharge; however, the difference between the minimum and maximum values (Δνι ) Is not greater than 0.100, and when the discharge capacitance ratio is 0%, the difference between the minimum value and the discharge voltage UV2) is not greater than 0.3 (ν); the degree of voltage drop is smaller than the conventional case. In Figure 3, the discharge curve contains the first & paper size in the direction of increasing the discharge permittivity. The paper size applies the Chinese National Standard (CNS) A4 specification (21〇X 297 public love) '" " " — ----- 28 311440 492207 A7 B7 V. Description of the invention (29) Maximum value, minimum value, and second maximum value; At the same time, a drop in voltage was observed at the beginning of the discharge; however, the difference between the minimum value and the second maximum value (Δνΐ) • Not more than 0.1 (V), and when the discharge capacitance is 0 ° /. When the minimum value and discharge; the voltage difference (△ V2) is not greater than 0.3 (V); the voltage drop is smaller than the conventionally known:-shape. As shown in Figures 1 to 3, the discharge capacity (mAh) at 1 ° C at -20 ° C is not less than 60% of the discharge capacity (mAh) at 1 ° C at 20 ° C. Therefore, in the extremely low temperature region, the decrease in the discharge capacitance is small. This lithium ion secondary battery i. It is possible to suppress a sharp drop in the initial voltage of the discharge in the extremely low temperature region. In addition, reduction in discharge capacitance can be suppressed. The electrolyte of the lithium ion secondary battery preferably includes at least one member selected from the group consisting of ethylene carbonate, propylene carbonate, dimethyl carbonate, and diethyl carbonate and ethyl methyl carbonate. As a solvent, a mixed solvent of a specific ratio shown in a lithium ion secondary battery is used. Please read the notes on the back before filling this page k

Printed by a member of the Ministry of Economic Affairs, Intellectual Property, Property, and Consumer Affairs Co., Ltd. The lithium salt dissolved in the electrolyte is preferably used for the aforementioned fifth lithium ion secondary battery. That is, the electrolyte is preferably adjusted to have a bell salt concentration of 0.5 mol / L to 1.5 mol / L, and more preferably 0.7 mol / L to 1.2 mol / L. The bell ion secondary battery of the present invention can be used without limitation as various lithium ion secondary batteries having a shape such as a cylindrical shape, a square shape, or a plate shape. The bell ion secondary battery of the present invention can utilize various constituent elements such as a battery can, a battery cover, a safety structure, an electrode terminal, etc., which are conventionally available or will be developed in the future. [Explanation of preferred specific examples] The present invention will be described in more detail with reference to examples, but these examples do not limit the present invention. In addition, the comparative examples illustrate the significant effects of the present invention. This paper size applies the Chinese National Standard (CNS) A4 specification (21 × 297 mm) 29 311440 λ 492207 A7 B7 V. Description of the invention (30) 耋 Example 1 $ 4, Comparative Example 1 reverse 5 make (1; 〇 304 and Li2C03 are 42 parts by weight per 100 parts by weight of co3304.

Li2C03 was mixed in a proportion, and the homogeneous mixture was sintered at about 980 ° C for about 10 hours. The obtained LiCo0 2 bulk was pulverized, divided and heated in the air to obtain Uc00 2 particles of Examples 1 to 4 and Comparative Examples 1 to 5 shown in Table 1, among which LiC of Comparative Examples 1 to 3. The 02 particles were not subjected to the above-mentioned heat treatment. J1IJ ------ M Pack—— (Please read the precautions on the back before filling in this page) tr · · Heat Treatment of LiCo〇2 Particles of Examples and Comparative Examples printed by the Consumer Cooperatives of the Intellectual Property Bureau of the Ministry of Economic Affairs Conditions (temperature and hours), average particle size B after heat treatment, specific surface area A after heat treatment, specific surface area reduction due to heat treatment (ΔA), and (20 / (AB)) are shown in Table 2, where The average particle size B and specific surface area A of the LiCo02 particles in Comparative Examples 1 to 3 were obtained using particles that were not heat-treated. Table 1 Heat treatment average particle size B (// m) Specific surface area A (m2 / g) ΔΑ (%) 20 / (ΑΒ) Discharge capacity retention rate (%) Temperature re) Time (Hr) Example I 500 12 19.7 0.136 15.0 7.46 90 · 6— Example 2 700 12 19 · 9 0.H6 27.5 8.66 91.2 Example 3 500 12 16.4 0.157 21 · 5 7.76 91.5 Example 4 600 12 13.0 0.214 23.6 7.19 90.4 Comparative Example I--12.6 0.280- 5.67 83.1 Comparative Example 2--16.2 0.200 6.17 81.4 ~ Comparative Example 3-19.4 0.160-6.44 78.3 Comparative Example 4 800 12 17.6 0.H5 22.5 9.88 82.6 Comparative Example 5 800 12 20.9 0.096 38.0 9.97 82.3 Examples 1 to LiCo02 particles (90 parts by weight) of 4 and Comparative Examples 1 to 5 and a binder polyvinylidene fluoride (7 parts by weight), electroconductive agent acetylene carbon black (3 parts by weight), and N-methyl-2-D Pyrrolidone (70 parts by weight) is mixed to obtain pulp _% 311440 This paper size is applicable to China National Standard (CNS) A4 (210 X 297 mm) 492207

5. Description of the invention (3l). This slurry was applied to a 20 vm-thick aluminum that was to be used as a current collector. "From both sides, dried and extruded, an aluminum foil with a 20 mg / cm2 thick positive electrode active material composition layer on each side was obtained. Into the positive electrode.

Flaky graphite (90 parts by weight), polyvinylidene fluoride (1 (parts by weight)), and N · methyl-2_D than pyrrolidone (200 parts by weight) were mixed to obtain a slurry. Apply this slurry to both sides of the thick steel foil that is to be used as a current collector, please read the note on the back δ

The anode was made by drying and pressing to obtain a negative electrode made of a steel foil with a thickness of 10 4 mg / cm2 of a negative electrode active cold substance composition layer on each side. | — The positive and negative electrodes were wound through a porous polyethylene separator to obtain a cylindrical lithium ion secondary battery (discharge capacity: 1500 mAh) with a height of 65 mm and an outer diameter of 18 mm. As for the electrolyte, a solution obtained by dissolving 1 mol of LiPF6 in a mixed solvent containing ethylene carbonate, propylene carbonate, and diethyl carbonate (mixing volume ratio 3: 2: 5) was charged between the above-mentioned positive electrode and negative electrode. The charge and discharge cycle characteristics of the lithium ion secondary battery were evaluated according to the following charge and discharge cycle test methods. Table 1 shows the discharge capacity retention rate (%) at the 100th cycle. [Charging and Discharging Cycle Test Method] Order * Ministry of Economic Affairs ... Intellectual Property · Intellectual Property. The Bureau's Consumer Cooperatives printed a cycle including charging at a constant current of 2.6 mA and a constant voltage of 4.2 V per 1 cm2 of positive voltage for 2.5 hours. After charging Let stand for 1 hour, discharge at a constant current of 1.3 mA per 1 cm2 of the positive electrode until the terminal voltage reaches 3 V, and leave it for 1 hour after discharge. Repeat this cycle 100 times at room temperature (20 ° C). Calculate the discharge capacitance (mA · H) from the discharge current and discharge hours for each cycle. Discharge i The capacitance retention rate (%) is the ratio of each cyclic discharge capacitance to the initial discharge capacitance. 0 This paper size applies the Chinese National Standard (CNS) A4 specification (210 X 297 mm) 31 311440 492207 A7-B7 V. Invention Explanation (32) From Table 1, it can be seen that the lithium ion secondary battery containing the LiCo02 particles of Comparative Examples 1 to 5 in which the value of (20 / (AB)) falls outside the range of the aforementioned formula (1) as a positive electrode active material is in the first tenth. 〇The cycle shows the discharge capacitor retention rate not more than 85%. In contrast, a lithium ion secondary battery containing LiCo02 particles of Examples 1 to 4 having a value of (20 / (AB)) within the range of the foregoing formula (1) as a positive electrode active material was shown to be not less than 90% at the 100th cycle. Its high discharge capacity retention rate confirms its excellent charge and discharge cycle properties. Examples 5 to 10, Comparison 6 to 10 In the following Examples 5 to 10 and Comparative Examples 6 to 10, the average particle size of Li_transition metal composite oxide and the particle size of conductive materials with a particle size of not less than 1 # m Measured with SALD3 000J manufactured by SHIMADZU CORPORATION; the particle size of the conductive material with a particle size of less than 1 am, the aspect ratio and fiber diameter of the fibrous conductive material are measured with a scanning electron microscope (SEM). Example 5 LiCoO2 (90 parts by weight, average particle size 20 # m), spherical artificial graphite (6 parts by weight, particle size 6 # m), oil furnace black (1 part by weight, particle size 40 nm, specific surface area 700 m2 / g) , And polyvinylidene fluoride (3 parts by weight, a binder) were uniformly dispersed in N-methyl · 2-ΠBilodol: one to obtain a slurry. This slurry was applied to both sides of a 20 / zm-thick aluminum foil to be a current collector, dried, and extruded to obtain a positive electrode made of aluminum hafnium having 20 mg / cm2 LiCo02 on each side. i Example 6 Make LiCoO2 (90 parts by weight, average particle size 20 // m), artificial flakes. The size of this paper applies the Chinese National Standard (CNS) A4 (210 X 297 mm)% (Please read the precautions on the back first) Fill out this page again) -n I nnn ~ nn See you soon, I I- mmm— n Printed by the Consumers' Cooperative of the Intellectual Property Bureau of the Ministry of Economy 492207 A7 B7 V. Description of the invention (33) Graphite (5 parts by weight, particle size 10 vm) 1. Bulk artificial graphite (2 parts by weight, particle size 1 / zm, specific surface area 20mvg) and polyvinylidene fluoride (3 parts by weight, binder) are uniformly dispersed in N-methyl-2-ohrolidone to obtain Aggregate. In the same manner as in Example 5, a positive electrode having the same structure as in Example-5 was prepared using this slurry. The system was made from a 20 / zm thick aluminum foil with 20 mg / cm2 LiCo02 on each side. Example 7 LiCo〇2 (90 parts by weight, average particle size i5 / zm), artificial flaky graphite (6 parts by weight, particle size 丨 0 in m), and carbon fibers (1 part by weight 'fiber diameter. , 3 // m, aspect ratio 20) and polyvinylidene fluoride (3 parts by weight of 'binder') were uniformly dispersed in methyl-2-D-pyrrolidine to obtain a mass. In the same manner as in Example 5, a positive electrode having the same structure as in Example 5 was prepared by using this slurry, and Q was made of 20 m thick foil with 20 mg / cm2 LiCo〇2 on each side. Example Q 8 In the same manner as in Example 5, except that LiCo02 with an average particle size of 15 was replaced by LiCo02 with an average particle size of 20 / zm, a positive electrode having the same structure as that of Example 5 was prepared, with 20% on each side. Made of 20 / zm aluminum foil with mg / cm2 LiCo02. 'Example 9 In the same manner as in Example 5, except that artificial spherical graphite (particle size 10 # m) was used instead of artificial spherical graphite (particle size 6 / zm), a positive electrode having the same structure as in Example 5 was prepared. It is made of 20 // m thick aluminum foil with 20 mg / cm2 LiCo02 on each side. -------------- Packing --- (Please read the precautions on the back before filling this page ). Ministry of Economic Affairs ^ Yuehui Property Bureau employee consumer cooperatives printed this paper standard applicable to the national standard (CNS) A4 specifications (210 X 297 issued) 33 311440 A7

V. Description of the invention (34) 492207 Implementing you 丨 10 In the same manner as in Example 5, except that the amount of artificial spherical graphite is 4.5 parts by weight and the amount of oil furnace black is 25 parts by weight, it has the same properties as in Example 5. The positive electrode with the same structure is made of 20 / im thick aluminum foil with 20 mg / cm2 LiCo〇2 on each side. Comparative Example 6 LiCoO2 (94 parts by weight, average particle size 20 m), oil furnace black parts by weight 'particle size 40 nm, specific surface area 700 m2 / g) and polyvinylidene fluoride (3 parts by weight, binder) were made uniform It was dispersed in N_methyl_2 · π-pyrrolidone to obtain a charge. In the same manner as in Example 5, a positive electrode having the same structure as in Example 5 was prepared using this slurry, and was made of 20 m thick aluminum foil with 20 mg / cm2 LiCo02 on each side. Comparative Example 7 LiCo〇2 (90 parts by weight, average particle size 20 / zm), artificial flaky graphite (7 parts by weight, particle size 10 # m), and polyvinylidene fluoride (3 parts by weight, binder) were uniformly dispersed in In N-methyl · 2 · Π than pyrrolidone, a slurry was obtained. In the same manner as in Example 5, a positive electrode having the same structure as in Example 5 was prepared using this slurry, and was made of 20 m thick aluminum foil with 20 mg / cm2 LiCo02 on each side. Comparative Example 8 In the same manner as in Example 5 except that LiCo02 with an average particle size of 5 # m was used instead of LiCo02 with an average particle size of 20 / zm, a 20 / zm thick aluminum foil with 20 mg / cm2 LiCo02 on each side was prepared.成 之 POSITIVE. Comparative Example 9 --SII ί · — I 1 IIII-· I 1 I l · — .1--Order · ---— II ---. (Please read the note on the back of the page before completing this page) Printed by the Intellectual Property Bureau of the Ministry of Economic Affairs of the Consumer Cooperatives. The paper size is applicable to the Chinese National Standard (CNS) A4 specification (210 X 297 mm) 34 311440 492207 Printed by the Intellectual Property Bureau of the Intellectual Property Bureau of the Employees Consumer Cooperatives. ) LiCoO2 (90 parts by weight, average particle size 5 // m), artificial flake graphite (7 parts by weight, particle size 5 / zm) and polyvinylidene fluoride (3 parts by weight, binder) are uniformly dispersed in N- In methyl-2-¾rolidone, a slurry was obtained. A positive electrode having the same structure as in Example 5. was prepared using this slurry in the same manner as in Example 5. It was made of a 20 / zm thick aluminum foil with 20 mg / cm2 LiCo02 on each side. Comparative Example 10 LiCoO2 (90 parts by weight, average particle size 20 / zm), artificial flaky graphite (6 parts by weight, particle size 10 # m), graphitized carbon fibers (1 part by weight, fiber diameter 5 / zm, aspect ratio 2- 3) and polyvinylidene fluoride (3 parts by weight, a binder) are uniformly dispersed in N-methyl-2-Π-pyrrolidone to obtain a slurry. In the same manner as in Example 5, a positive electrode having the same structure as in Example 5 was prepared using this slurry, and was made of a 20 / z m thick aluminum foil with 20 mg / cm2 LiCo02 on each side. The positive electrodes prepared in Examples 5 to 10 and Comparative Examples 6 to 10 were wound with a porous separator made of polypropylene and polyethylene and a negative electrode containing graphitized carbon fiber as a negative electrode active material, and placed at a height of 65 mm. In a cylindrical can with an outer diameter of 18 mm., A lithium-ion secondary battery (discharge capacity · 1500 .mAh) was prepared. As for the electrolyte, a solution of LiPF6 in a mixed solvent containing ethylene carbonate, propylene carbonate and diethyl carbonate (mixing volume ratio 3: 2: 5) was used, and the obtained concentration was 1 mol / L. The lithium-ion secondary battery was charged and discharged in accordance with the following test methods. The electric cycle test, the high-rate discharge test, and the nail penetration test. The results are shown in Tables 2 and 3. ------------- install ---- l · --- order --------- line (please read the precautions on the back before filling this page) Applicable to China National Standard (CNS) A4 (210 X 297 mm) 35 311440 4 ^ 2207 A7

(1) Charge the battery at 1.5 A for 2 hours until the voltage becomes 4 2 v, (ii) Discharge at 1.5 A until the voltage between the terminals becomes 3 V, and (η) discharge (please read the precautions on the back first) Write this page again) and let stand for 1 hour, these two steps constitute a cycle. Repeat these two steps at room temperature (20 ° C) for 100 cycles, and measure the discharge capacitance (Ah) of each cycle and the average discharge voltage of each cycle. The ratio of the discharge capacity of each cycle to the initial discharge valley was taken as the discharge capacity retention rate (%). The discharge capacity, average discharge voltage, and discharge capacity retention rate in the initial cycle and the 100th cycle are shown in Table 2. [High-rate discharge test method] The high-rate discharge of the battery includes: charging at 15 A for 2 hours to the voltage It became 4 · 2 V, and the voltage between the discharge to the end point was 3 v, and the voltage between the discharge and the end point was 3 v. After the discharge, it stood for 1 hour, and was charged at 15 A for 2 hours until the voltage became 4 2 V, and the discharge was made to 3 A. The voltage between the points becomes 3 v. Measure the discharge capacitance (a value) of 3 A discharge, the discharge capacitance (1) value of 3 A discharge, and its ratio (b / a). [[Iron nail penetration test method] The battery was charged at 1 · 5 A to a voltage of 4 3 V, and immediately after that, an iron nail with an outer diameter of 3 mm was inserted at 4 cm / sec to penetrate into the vicinity of the center of the battery, between the positive terminal and the negative terminal. Check the burning situation of the battery, and calculate the number of batteries that burn because of this. IX 297 mm) 36 311440 492207 A7 B7 V. Description of the invention (37) Table 2 Charge and discharge cycle test printed by the Consumer Cooperatives of the Intellectual Property Bureau of the Ministry of Economic Affairs 1st cycle 100th test a Discharge capacitor (mAh) Average discharge voltage (V) Discharge capacitance (mAh) Average discharge voltage (V) Discharge capacitance retention rate (%) Example 5 1500 3.74 1420 3.70 95 Example 6 1500 3.72 1400 3.69 93 Example 7 1500 3.71 1400 3.69 93 Example 8 1500 3.75 1410 3.71 94 Example 9 1500 3.73 1420 3.69 95 Example 10 1500 3.74 1390 3.69 93 Comparative Example 6 1500 3.65 1250 3.58 83 Comparative Example 7 1500 3.62 1230 3.56 82 Comparative Example 8 1500 3.73 1250 3.62 83 Comparative Example 9 1500 3.62 1200 3.55 80 Comparative Example 10 1500 3.62 1220 3.56 81 Table 3 Discharge capacitance (mAh) Iron nail penetration test 0.3 A Discharge (a) 3 A Discharge (b) Discharge capacitance ratio (b / a) Number of batteries burned in 20 batteries (Batteries) Example 5 1550 1460 94 0 Example 6 1550 1440 93 0 Example 7 1550 1450 94 0 Example 8 1550 1470 95 0 Example 9 1550 1450 94 0 Example 10 1550 1430 92 10 Comparative Example 6 1560 1340 86 0 Comparative Example 7 1560 1330 85 0 Comparative Example 8 1550 1430 92 20 Comparative Example 9 1570 1300 83 1 0 Comparative Example 10 1560 1320 85 0 This paper is in accordance with the Chinese National Standard (CNS) A4 specification (210 X 297 mm) 37 311440 ------------- II --- (Please read the notes on the back before filling out this page)-Line · 492207 A7 B7 V. Description of the invention (38) Tables 2 and 3 clearly show that the discharge capacity, average discharge voltage, and discharge capacity retention rate of the 100th cycle of the ion secondary batteries of Examples 5 to 10 of the present invention in the charge and discharge cycle test. The b value and discharge capacity ratio in the high-rate discharge test are better than those of the bell-ion secondary battery of Comparative Examples 6 to 10. In addition, it also showed excellent results in the nail penetration test, confirming its high safety. In general, high-rate discharge is sensitively affected by the electrode resistance of a lithium-ion secondary battery ', among which higher electrode resistance reduces the discharge capacitance. Larger b and b / a values mean lower electrode resistance. In Table 2, the lithium ion secondary batteries of Examples 5 to 10 of the present invention have a larger value compared with the lithium ion secondary batteries of Comparative Examples 6 to 10, which are smaller. Obviously, the electrode resistance is the effect of using a larger-sized conductive substance and a smaller-sized conductive substance together. In the iron nail penetration test, the ion secondary batteries of Comparative Examples 6, 7, 9, and 10 showed superior results, which was achieved by losing their charge and discharge cycle properties and south-rate discharge properties. In the lithium ion secondary battery of Comparative Example 8, the average particle size of ' LiCoO2 was reduced to 5 to m to improve the charge and discharge cycle characteristics of the battery. As a result, the performance was poor in the nail penetration test. Examples 11 to 25 and Comparative Examples 11 to The mixed solvents of the negative electrode, the positive electrode, and the electrolyte required for manufacturing the lithium ion secondary batteries of the Examples and Comparative Examples were prepared by the following methods. [Preparation of positive electrode]

Prepare the following (A-1, A-2) as the positive electrode active material: (A-1) LiCo02: average particle size is (for SHIMADZU C, please read the note on the back first? Matters before filling this page) Order ·

Printed by the Intellectual Property Bureau Employee Consumer Cooperatives of the Ministry of Economic Affairs This paper is printed in accordance with Chinese National Standard (CNS) A4 (210 X 297 public love) 38 311440 Ministry of Economic Affairs' Intellectual Property Bureau Employee Consumer Cooperatives printed by 492207 A7 B7 V. Description of the invention ( 39) SALD3000J manufactured by Corporation, same as below), specific surface area is 0 · 160 m2 / g (measured by 'monosorb manufactured by QUANTA CHROME, same below); < (A-2) LiC 〇02: average particle size is 18.4 #m and specific surface area are 0.138 m · g2 / g. LiCo〇2 (90 parts by weight), polyvinylidene fluoride (7 parts by weight, adhesive), acetylene black (3 parts by weight, conductive agent), and N-formaldehyde The base-24 was mixed with pyrrolidine (7〇 | parts by weight) to obtain a slurry. This slurry was applied to both sides of a 20-thick aluminum foil that was to be used as a current collector, and the results of drying and pressing were used to produce two kinds of IS made of IS with a 20 mg / cm2 thick positive electrode active material composition layer on each side. The positive electrode, that is, LA-1 (positive electrode active substance: A-1) and LA-2 (positive electrode active substance: A-2). [Preparation of negative electrode] Six types (C-1 to C-6) of graphitized carbon shown in Table 4 below were prepared as a negative electrode active material. Among them, 'C -1 to C-3 are included in the present invention and C-4 to P C-6 are used for comparison. Graphitized carbon (90 parts by weight), polyvinylidene fluoride (10 parts by weight, a binder) and methyl winter pyrrolidone (200 parts by weight) were mixed to obtain a slurry. 2. Apply this slurry to the double-sided 14 // 111-thick steel reeds that are to be used as current collectors, and the results of drying and stretching are used to prepare a negative electrode active material composition layer with 10.4 mg / cm2 thick on each side. Six types of negative electrodes made of copper foil, that is, GC-1 (negative electrode active material · Cl), GC-2 (negative electrode active material: cj), GC-3 (negative electrode active material · C-3), GC-4 (negative electrode active material: C-4), GC-5 (negative electrode active --------- --------- · ---- order ------- --- line (please read the notes on the back before filling this page) This paper size applies to China National Standard (CNS) A4 (210 X 297 mm) 39 311440 492207 A7 B7 V. Description of the invention (40) Sexual substances: C-5) and GC-6 (negative electrode active material: C-6) Table 4 Negative electrode active material C-1 C-2 C-3 C-4 C-5 C-6 Specific surface area (m2 / g) 1.2 1.4 0.7 8.7 1.9 4.5 D002 (nm) 0.3366 0.3361 0.3359 0.3354 0.3420 0.3368

(Please read the precautions on the back before filling this page) Printed by the Consumer Cooperatives of the Intellectual Property Bureau of the Ministry of Economic Affairs [Preparation of Electrolyte Solvents] Prepare various Tibetan solvents as shown in Table 5 below as electrolyte solvents. Of the 18 mixed solvents shown in Table 5, ten MS-1 to MS-1 j are used in the present invention, and seven species MS-12 to MS-18 are used for comparison. Table 5 Mixed solvent components (% porcine ratio) EC PC DEC EMC DMC MS-1 6 9 4 31 50 MS-2 8 12 4 29 47 MS-3 10 15 4 27 44 MS-4 8 7 4 31 50 MS-5 11 9 4 29 47 MS-6 14 ^ 11 4 27 44 MS-7 11 5 4 31 —50 MS-8 14 6 4 29 —47 MS-9 18 8 4 27 44 MS-10 11 9-33 47 MS-11 11 9 33 • 47 MS-12 32-19 36 14 MS-13 37-63-MS-14 42-36 ~ Γ7 5 MS-15 25--50 25 MS-16-25-i5 0 25 MS-17 30 10-60-MS-18 42 36 17 5 This paper size is in accordance with Chinese National Standard (CNS) A4 (210 X 297 mm) 40 311440 492207 A7 B7 Comparative Examples 11 to 17 V. Description of Invention (41 ) Fu Shai teaches to 21 Wound the aforementioned positive electrode LA-1 and negative electrode GC-1 through a porous polyethylene-polypropylene composite separator to obtain a cylindrical lithium ion secondary battery with a height of 65 mm and an outer diameter of 18 mm (discharge Capacitance: 1300 mAh). As for the electrolyte, a solution obtained by dissolving 1 mol of LiPF6 in a mixed solvent (i L) shown in Table 5 was charged between the positive electrode and the negative electrode. Table 5 shows the types of mixed solvents used in the examples and comparative examples. Examples 22 to 25, Comparative Examples 18 to 20 In the same manner as in Examples 11 to 21 and Comparative Examples 11 to 17, and using the positive electrode, negative electrode, and mixed solvent shown in Table 7, the positive electrode and negative electrode were passed through porous polyethylene. -Polypropylene composite separator is wound to obtain a cylindrical lithium ion secondary battery (discharge capacitance: uoo mAh) with a height of 65 mm and an outer diameter of 18 mm. As for the electrolyte, as described in the implementation of π, it will dissolve 1 mole of LiPF6 The solution obtained in the mixed solvent (1 L) was charged between the positive electrode and the negative electrode. The charge and discharge cycle characteristics of the lithium-ion secondary batteries of the above examples and comparative examples were measured according to the following charge and discharge cycle test methods, and the discharges at the 100th, 200th, 300th, and 400th cycles were calculated. Capacitance retention rate (%). The results of Examples 11 to 21 and Comparative Examples 11 to 17 are shown in Table 6; the results of Examples 22 to 25 and Comparative Examples 18 to 20 are shown in Table 7. In Comparative Examples 15 and 17, the decomposition of the PC prevented the charge and discharge cycle tests from being performed. In Comparative Example 18, when the test was terminated, the discharge capacity retention rate at the 100th cycle was reduced to 38%. i [Charge and discharge cycle test method]

One cycle includes a constant current of 2.6 mA and a positive voltage of 4.2 V per 1 cm2. The paper size is applicable to the Chinese National Standard (CNS) A4 specification (2㈣7 public love) 41 31144〇 ------------- install- ----: ---- Order --------- line (Please read the note on the back? Matters before filling out this page) Printed by the Economic and Intellectual Property Bureau Staff Consumer Cooperatives Printed by the Ministry of Economic Affairs Intellectual Property Bureau Printed by the employee consumer cooperative 492207 A7 B7 V. Description of the invention (42) Charge at constant voltage for 2.5 hours, leave it for 1 hour after charging, discharge at a constant current of 2.6 m A per 1 cm2 of positive current to a terminal voltage of 3 V and Let stand for 1 hour after discharge. Repeat this cycle 400 times at room temperature (20 ° C). Calculate the discharge capacitance (m A · H) from the discharge current and discharge hours for each cycle. The ratio of the cyclic discharge capacity to the initial discharge capacity was taken as the discharge capacity retention rate (%). (Please read the notes on the back before filling this page)

Table 6 Discharge capacity retention rate of positive and negative mixed solvents in each cycle (%) 100th cycle 200th cycle 300th cycle 400th cycle Example 11 LA_1 GC-1 MS-1 88 84 77 72 Example 12 LA-1 GCA MS-2 88 83 77 73 Example 13 LA-1 GC-1 MS-3 88 81 74 67 Example 14 LA_1 GC-1 MS-4 87 82 74 69 Example 15 LA-1 GC-1 MS-5 90 81 76 70 Example 16 LA-1 GC-1 MS-6 88 76 70 67 Example 17 LA-1 GC-1 MS-7 86 76 68 63 Example 18 LA-1 GC-1 MS-8 86 75 68 60 Example 19 LA-1 GC-1 MS-9 86 75 68 60 Example 20 LA-1 GC-1 MS-10 86 78 70 67 Example 21 LA-1 GC-1 MS-11 88 80 72 69 Compare Example 11 LA-1 GC-1 MS-12 81 68 55 46 Comparative Example 12 LA-1 GC-1 MS-13 79 57 47 38 Comparative Example 13 LA-1 GC-1 MS-14 77 56 46 38 Comparative Example 14 LA-1 GC-1 MS-15 84 70 58 52 Comparative Example 15 LA-1 GC-1 MS-16---Comparative Example 16 LA-1 GC-1 MS-17 84 68 53 40 Comparative Example 17 LA-1 GC-1 MS-18----This paper size applies to China National Standard (CNS) A4 (210 X 297 mm) 42 311440 492207 V. Description of the invention (43) A7 B7 Table 7 Positive and negative electrodes Discharge capacity retention rate of mixed solvent in each cycle 100th cycle 200th cycle 300th cycle 400th cycle Example 22 LA-1 GC-2 MS-5 87 81 77 73 Example 23 LA-1 GC-3 MS-5 92 87 83 80 Example 24 LA-2 GC-1 MS-1 88 82 78 72 Example 25 LA-2 GC-1 MS-2 88 83 79 74 Comparative Example 18 LA-1 GC-4 MS-5 38 sides -Naming Comparative Example 19 LA-1 GC-5 MS-5 79 68 58 53 Comparative Example 20 LA-1 GC-6 MS-5 71 62 52 47 As shown in Tables 6 and 7, compared with Comparative Examples 11 to 20 Next, all the lithium ion secondary batteries of Examples 11 to 25 had a slowly decreasing discharge capacity retention rate. At the 400th cycle of each comparative example, the discharge capacity retention ratios were all lower than 60%, but not in the examples. Particularly remarkable facts are the lithium ion secondary battery using each of the examples of EC and PC, and comparative example 15 in which MS-16 is not used in EC, and comparative example 11 in which MS-12 and MS-14 are not used in PC. 13. Compared with Comparative Example 16 in which MS-17 is not used with DMC, it has significantly superior charge and discharge cycle properties. This effect is apparently caused by the use of both EC and PC when graphitized carbon is used as the negative electrode active material. In addition, it is apparent from Table 7 that when using a negative electrode containing graphite carbon that is outside the scope of the present invention, the charge and discharge cycle properties are insufficient. In Comparative Example 18 and Comparative Example 20, PC was decomposed due to the use of graphitized carbon having an excessively high specific surface area and high crystallinity; unlike Comparative Example 1 and Comparative Example 17, it was possible due to the protective film of EC Charge and discharge. In Comparative Example 19, the paper size is adapted to the Chinese National Standard (CNS) A4 (210 X 297 mm) 43 311440 --- II--II ----- --- (Please read the back first Please pay attention to this page and fill in this page again) Order: --Line · Printed by the Ministry of Economic Affairs, Intellectual Property Bureau Staff Consumer Cooperative 492207 A7 ~ ——-------- 5. Description of the invention (44) Use of low crystallinity graphite Carbon (soft carbon), pc does not decompose, but the reversibility of lithium intercalation reaction is insufficient, and then the charging and discharging cycle properties are insufficient. Compound Ai columns 26 to 29 and specific conversion examples 91, 22 t Example 26 [Preparation of positive electrode] To be used as a positive electrode active material, average particle size 20 β m (measured by salD_ 3000J), specific surface area 012 mVg, and [2〇 (Average particle size X specific surface area)] LiCo〇2 (91 parts by weight) of 8.3; spherical shape to be used as a conductive material

Graphitized carbon (MCMB 6_28, 5 parts by weight, particle size 6 # m); KETZEN BLACK ECP (1 part by weight, particle size 0 · 01 to m); and polyvinylidene fluoride (PVdF) (3 parts by weight, adhesive) uniform Dispersed in N-methyl-2-pyrrolidone 'to obtain a slurry. This slurry was applied to both sides of a 20-thick aluminum foil to be used as a current collector, dried and stretched to obtain a positive electrode made of aluminum foil with 20 mg / cm2 LiCo02 on each side. [Preparation of Negative Electrode] Graphitized carbon (Melblonmilled FM-14) (95 parts by weight, negative electrode active material, specific surface area: 1.32 m2 / g, lattice plane (d002) interval · 0.33 nm or less, c-axis direction Crystallite size: 50 nm), polyvinylidene fluoride (PVdF) (5 parts by weight, negative electrode binder) and N-methyl-2-Π-pyrrolidone (50 parts by weight) were mixed to obtain a slurry. This slurry was applied to a double-sided 14 / zm thick copper foil which was to be used as a current, dried, and stretched to obtain a negative electrode. [Preparation of Electrolyte] Paper containing diethyl carbonate (4% by volume), ethyl methyl carbonate (29% by volume), ethylene carbonate (11% by volume), propylene carbonate (9% by volume), and carbonate paper Applicable to China National Standard (CNS) A4 specification (210 X 297 public love) -1 ^ ---- Γ --------- (Please read the precautions on the back before filling this page) Order:

Printed by the Employees 'Cooperatives of the Intellectual Property Bureau of the Ministry of Economic Affairs 492207 A7 ---- B7 Printed by the Employees' Cooperatives of the Intellectual Property Bureau of the Ministry of Economic Affairs. The electrolyte was obtained by reducing the concentration to mol / L (relative to the electrolyte after preparation). [Assembly of Lithium-ion secondary battery]. The positive and negative electrodes prepared above were wound through a porous polyethylene-polypropylene composite separator and placed in a cylindrical battery can (18 mm in outer diameter and 65 mm in height). . The separator was impregnated with the electrolyte prepared as described above to obtain the lithium ion secondary battery of the present invention. The lithium ion secondary battery prepared as described above was subjected to a cycle property test, a low temperature property test, and a storage property test. The results are shown in Table 8. [Cycle property test] At room temperature (20 ° C), the lithium ion secondary battery prepared as described above was charged and discharged at 1C / 1C for 5000 cycles. From the discharge current and the discharge hour, calculate the discharge capacitance [0 1 person · H] in the first cycle and the 500th cycle. Divide the discharge capacitance [mA · Η] in the 500th cycle by the discharge capacitance · H] in the first cycle to obtain the discharge capacitance retention (%). The results are shown in Table 8. [Low-temperature property test] The lithium ion secondary battery prepared above was charged at room temperature, and left at _35 ° C in the air for 24 hours. The battery was charged with a constant current of 1C (1600 mA) until the voltage reached 4 · 2 V, and then the current was charged at a constant voltage of 4.2 V for a total of 2.5 hours; at -35 ° C in the atmosphere at 0.5 C ( 800 mAh) / 2,5 V cut-off voltage to discharge the battery, and calculate the discharge capacitance (mA · H) at this time. At room temperature (20 ° C) and under the same conditions, charge and discharge and calculate the discharge capacitance (mA · Η). Divide the discharge capacitance [mA · H] at -3 5 ° C by the discharge capacitance [mA · H] at room temperature to obtain the paper size. Applicable to China National Standard (CNS) A4 (210 X 297) 45 311440 ------------- 05 ^ --- (Please read the precautions on the back before filling this page) Γ 良 ^ VZZOl Α7 V. Description of the invention (46 Capacitor retention rate ( %). The results are shown in Table 8. [Storage property test] The lithium-ion secondary battery prepared above was charged to a container and left at 60 ° C for 40 days in the atmosphere. The battery was charged at 1C (1600 mA) The constant current flows until the electricity becomes 4 2 V, and then the current flows at a constant voltage of 4 2 V for a total of 25 hours of charging; Yu Qiao. c. The battery is left to stand for 24 hours in the atmosphere and at _5 ° C In the atmosphere, the battery is discharged with a cut-off voltage of jc (1600 mAh) / 2 5 v, and the discharge capacitance (m A · η) at this time is calculated. Divide this discharge capacitance by the RT discharge capacitance (with ic (16 〇〇mAh) / 2 5 v cut-off voltage) to obtain the capacitance retention rate. The results are shown in Table 8. The RT discharge capacitor used in this article means that by making a constant current of 1600 Until the voltage reaches 4 · 2 V, a constant voltage of 4.2 V is applied to allow current to flow for a total of 2.5 hours, and then at 20. (: Discharge capacitance obtained by discharging at 800 mA to a voltage of 2 · 5 V (mA · η). Example 27 In the same manner as in Example 20, except that LiCoO2 having an average particle size of i 6 # m and a specific surface area of 0.17 m 2 / g was used as a positive electrode active material, a secondary ion battery was prepared. This clock The ion secondary battery was subjected to the cycle property test, low temperature property test, and storage property test in the same manner as in Example 26. The results are shown in Table 8. Example 28 In the same manner as in Example 26, except that the graphitization with particle size 4 was used Carbon and particle size 0 05 // m KETZEN BLACK as a conductive material to produce a lithium ion secondary battery. This lithium ion secondary battery and Example 26 Please read the precautions on the back before filling in this page to order the Intellectual Property Bureau of the Ministry of Economic Affairs Printed on employee papers by consumer cooperatives. Applicable to China National Standard (CNS) A4 specifications (210 X 297 public love) 46 311440 492207 Printed on A7 by employee consumer cooperatives of the Intellectual Property Bureau of the Ministry of Economic Affairs 5. Description of invention (47 ) The same was performed for the cycle property test, low temperature property test, and storage property test, and the results are shown in Table 8. Example 29 v In the same manner as in Example 26 except that diethyl carbonate-containing (6 vol%) was used A mixed solvent of ethyl methyl carbonate (27% by volume), ethylene carbonate (9% by volume), propylene carbonate (10% by volume 0/0) and dimethyl carbonate (48% by volume) was used as an electrolyte solvent to prepare Lithium-ion secondary battery. This lithium ion secondary battery was tested in the same manner as in Example 26. The cycle property test, low-temperature property test, and storage property test were performed. The results are shown in Table 8 < > Comparative Example 21 In the same manner as in Example 2.6, except that Use Lic〇002 [average particle, degree 18 "m, specific surface area 0.19 m2 / g, 20 / (average particle size, specific surface area) · 5.8] as the positive electrode active material; spherical graphitized carbon 6-28 alone 6 parts by weight, with a particle size of 3 // 00 as a conductive substance; a mixed solvent containing ethylene carbonate (30% by volume), propylene carbonate (30% by volume), and dimethyl carbonate volume. An electrolyte solvent was used to prepare a lithium ion secondary battery. This lithium ion secondary battery was subjected to a cycle property test, a low temperature property test, and a storage property test in the same manner as in Example 26. The results are shown in Table 8. Comparative Example 2 Example 26 was performed in the same manner, except that LiCo〇2 [average particle size and specific surface area of 010 m2 / g, 20 / (average particle size x specific surface area): 10 · 5] was used as the positive electrode active material; carbon black alone was used in parts by weight, particle size 0〇1Product Π1) as a conductive substance; containing carbonic acid A mixed solvent of olefin ester and 0 vol% acrylic acid S (20 vol%) and dimethyl carbonate (60 vol%) is used as the standard for this paper. Chinese National Standard (CNS) A4 specification (210 X 297) « )-47 311440 -n IH ϋ ί nn II -ϋ I · ϋ I · ϋ nna ^ i an II 』: ° J · an ϋ n ϋ I · I n I (Please read the precautions on the back before filling in this Page) 492207 A7 B7 V. Description of the invention (48) (Please read the precautions on the back before filling this page) The lithium ion secondary battery was prepared as an electrolyte solvent. This ion secondary battery is the same as in Example 26. The cycle property test, low temperature property test, and storage property test were performed, and the results are shown in Table 8. Table 8 Example 26 Example 27 Example 28 Example 29 Comparative Example 21 Comparative Example 22 [Cyclic property J Discharge capacitance retention rate (%) 85 82 83 80 50 40 [Low temperature property] Discharge capacitance retention rate (%) 88 83 81 81 Not discharged 20 [Storage property] Discharge capacitance retention rate (%) 80 82 82 81 Undischarged and undischarged from the above Examples 26 to 29 And Comparative Examples 21 and 22 show that the lithium ion secondary battery using the present invention is used. Charging and discharging cycle properties, storage properties, and low-temperature properties were significantly improved. Examples 30 to 38 and Comparative Examples 23 to 27 [Preparation of Electrolyte] Printed by the Consumers ’Cooperative of the Intellectual Property Bureau of the Ministry of Economic Affairs for Examples 30 to 38 and The electrolyte solvents of the lithium ion secondary batteries of Comparative Examples 23 to 27 were prepared at the mixing ratios shown in Table 9. LiPF0 was dissolved in each solvent to a concentration as shown in Table 9 to obtain electrolytes for each ion secondary battery. [Preparation of the positive electrode] LiCo〇2 (91 parts by weight, positive electrode active material) with an average particle size of 17.5 "m (measured by SALD_3000J) and a specific surface area of 0.154 m2 / g; graphite This paper applies the Chinese National Standard (CNS) A4 specification (210 X 297 mm) 48 311440 492207 A7 B7 V. Description of the invention (49) (Please read the precautions on the back before filling out this page) Powder (6 parts by weight, positive conductive material); polyvinylidene fluoride (3 weight Parts, positive electrode binder) and N-methyl-2-¾rolidine (50 parts by weight) were mixed to obtain a slurry. The slurry was applied to a thickness of 20 / zm to be a current collector. Aluminum and foil (550 mm X 55 mm) were double-sided, dried and stretched to obtain a positive electrode. The positive-polar active material layer filling rate was 70%. Thirteen sets of this positive electrode were manufactured for Examples 30 to 37 and Comparative Examples 23 to For lithium ion secondary batteries of 27. In the same manner as above, but using an average particle size of 16 ►Specific surface area is 0.138 〇12々 of 1 ^ <: 0, different positive electrodes were prepared. This positive electrode shows a positive electrode active material The filling rate of the layer was 74%. Using this positive electrode, the lithium ion secondary battery of Example 38 was prepared. [Preparation of Negative Electrode]-Intellectual Property and Intellectual Property of the Ministry of Carbon, made with an average fiber length of 40 // m and an average fiber diameter of 8 · 8 β m. Printed fibers (95 parts by weight, negative active material) of the Bureau ’s Consumer Cooperative, Polyvinylidene fluoride (5 parts by weight, a negative electrode binder) and N-methyl-2-Π-pyrrolidone (100 parts by weight) were mixed to obtain a slurry. This slurry was applied to the intended solution. 14 of the current collector was 111-thick ►copper foil (595 mm X 57 mm) on both sides, dried and pressed to obtain a negative electrode. The negative electrode active material layer filling rate was 69/0. 13 sets of this negative electrode were manufactured for implementation- For lithium ion secondary batteries of Examples 30 to 37 and Comparative Examples 23 to 27. η. In the same manner as above, except that carbon fibers having an average fiber length of 35〆m and an average fiber diameter of 10 // m were used, different results were obtained. The negative electrode. This negative electrode shows a filling rate of the negative electrode active material layer of 72/0. The negative electrode was used to prepare the lithium ion secondary battery of Example 38. i [Assembly of lithium ion secondary battery] The above was obtained The positive and negative electrodes are applied through porous polyethylene-polypropylene paper. National Standards (CNS) A4 size (210 X 297 mm) 49311440492207

V. Description of the invention (50) The separator is wound and placed in a cylindrical battery can (18 mm outside diameter, height order °) The electrolyte prepared above is filled between the positive and negative electrodes. ^ F Please read the precautions on the back first (Fill in this page again) To the lithium-ion dianjis of Examples 30 to 38 and Comparative Examples 23 to 27 [Evaluation] person ^ also. The lithium ion secondary batteries of Examples 30 to 38 and Comparative Examples 23 to 27 prepared above were charged at room temperature, which were charged at a constant current of 1C (1600 mA) until the voltage became 4 2 v, and then 4.2 V constant voltage charging, although charging time reaches 2.5 hours, charging stops. The lithium ion secondary battery was placed in a constant temperature bath at -3 ° C and discharged at a cut-off voltage of 0 5 c (800 mAli) /2.5 V. Measure the discharge current and discharge hours of each lithium ion secondary battery at this time, and calculate the discharge capacity (mAh). Divide this discharge capacity by the discharge capacity (mAh) at room temperature and multiply by 100 to get the discharge capacity retention rate (%). The results are shown in Table 9. The intermediate voltage obtained by dividing the energy (mWh) during discharge by the discharge capacity (mAh) during discharge is also shown in Table 9. Printed on the paper by the Consumers' Cooperative of the Intellectual Property Bureau of the Ministry of Economic Affairs, the paper size applies to the Chinese National Standard (CNS) A4 (210 X 297 mm) 50 311440 492207 A7 B7 V. Description of the invention (51) Table 9 Electrolyte Rose Capacitance Retention Rate— Medium Voltage (V) -__ 2.92 LiPF6 Mol / L EC Volume% PC Volume% DEC Volume% EMC Volume% DMC Volume% Example 30 1 8 12 15 30 35 80 Comparative Example 23 1 25 0 0 50 25 2.77 Example 31 1.4 8 12 17 29 34 71 2.94 Example 32 1.2 8 12 17 29 34 74 2.98 Example 33 1.0 8 12 17 29 34 ~~~ --- 77 ~ λ99 ^ Example 34 0.8 8 12 17 29 34 66 2.84 Comparison Example 24 1 0 10 15 30 35 No effect Comparative Example 25 1 10 0 15 40 35 52 2.82 Example 35 1 8 12 0 45 35 76 2.90 Example 36 1 8 12 10 35 35 76 2.89 Example 37 1 8 12 15 30 35 78 2.91 Example 38 1 10 10 0 40 40 77 2.93 Comparative Example 26 1 10 10 0 30 50 2 2.81 Comparative Example 27 1 10 10 0 60 20 43 2.75 (Please read the precautions on the back before filling this page ) As apparent from Table 9, compared with the lithium ion secondary batteries of Comparative Examples 2 3 to 27, the lithium ion of Examples 30 to 38 The secondary battery can suppress the reduction of discharge capacity (mAh) and intermediate voltage at low temperatures. Low temperature properties can be improved by adjusting the mixing ratio of the electrolyte components. Example 39 and Comparative Examples 28 to 30 printed by the Consumer Cooperative of the Bureau of Intellectual Property of the Ministry of Economic Affairs Example 39 [Preparation of the positive electrode] The average particle size to be used as a positive electrode active material was 18 / m (measured by SALD-3 000J) , Specific surface area 0.4 m2 / g, and [20 / (¥ average particle size x specific surface area)] LiCo〇2 (91 parts by weight) with a value of 7.9; the size of the paper intended to be used as a conductive material applies the Chinese National Standard (CNS) A4 specifications (210 X 297 mm) 51 311440 492207 A7 B7 V. Description of the invention (")

Shaped graphitized carbon (MCMB 6-28, 5 parts by weight, particle size 6 β m); KETZEN BLACK ECP (1 part by weight, particle size not greater than 0.01 / zm); and polyvinylidene fluoride (PVdF) (3 parts by weight, adhesive) Agent) uniformly dispersed in N-methyl-2-D ratio (please read the precautions on the back before filling out this page} Alkanone to obtain a slurry. Apply this slurry to the current collector A 20 # m thick aluminum foil was double-sided, dried and stretched to obtain a positive electrode made of IS foil with 20 mg / cm2 LiCo02 on each side. [Preparation of the negative electrode] Fibrous graphitized carbon (Melblonmilled FM-14) ( 95 parts by weight of a negative electrode active material), polyvinylidene fluoride (PVdF) (5 parts by weight of a negative electrode binder) and N-methyl-2-D than pyrrolidone (50 parts by weight) were mixed to obtain a slurry. This slurry was applied on both sides of a 14 # m thick steel book which was to be used as a current collector, dried and pressed to obtain a negative electrode. [Preparation of Electrolyte] In a solution containing ethylene carbonate (EC, 11% by volume), Propylene carbonate (PC, 9 vol. ° / 〇), diethyl carbonate (DEC, 4 vol.%), Ethyl methyl carbonate (EMC, 29 vol.%), And dimethyl carbonate (DMC, 47 vol.) %) In a mixed solvent (1 L) to dissolve 1 mol of LiPF6 to obtain an electrolyte. Printed by the Consumer Cooperative of the Intellectual Property Bureau of the Ministry of Economic Affairs [Assembly of Lithium Ion Batteries] The positive and negative electrodes prepared above were passed through porous polyethylene- A polypropylene composite separator was wound and placed in a cylindrical battery can (18 mm in outer diameter and 65 mm in height). The separator was impregnated with the electrolyte prepared above to obtain a lithium ion secondary battery of the present invention. [Discharge test] Charge the lithium-ion secondary battery prepared above at room temperature, which is in accordance with the Chinese National Standard (CNS) A4 (210 X 297 mm) at this paper size " 52 311440 492207 A7 V. Description of the invention (53 ) Charge at a constant current of 1600 mA until the voltage becomes 4 2 v, and then charge at a constant voltage of V. When the charging time reaches 35 hours, the charging is stopped.: Place the secondary ion battery in -2 (TC, air) 24 hours, then, •• Discharge at a cut-off voltage of 1.0 C (1600 mAli) / 2,5 V. Measure the electric discharge rate (A) and discharge voltage (V) at the time and plot it, where the horizontal axis is the discharge, Permittivity (%), ordinate It is the discharge voltage (V). As a result, as shown in Figure i, the graph shows that there is no slope of the minimum value, and no sharp voltage drop is seen. _►The discharge permittivity (%) is relative to 20. (: and 2.5 The discharge capacitance (100%) obtained by 1C discharge at V cut-off voltage. The discharge capacitance retention rate (%) and the intermediate voltage (V) were calculated. The results are shown in Table 10. Discharge capacitance retention rate (%) is the discharge capacitance (mA · H) when the voltage reaches 1C at -20 C and the voltage reaches the cutoff voltage (25V) divided by 2 (discharge at 1C of TC, the voltage reaches the cutoff voltage (2 · 5 V) is obtained from the discharge capacitance (mA · H). The intermediate voltage is the discharge capacitance (mA · H) when the voltage reaches 1C at -20 ° C and the voltage reaches the cut-off voltage (2 5 v). Obtained by 50% of the discharge energy (H). # Comparative Example 28 A positive electrode was obtained in the same manner as in Example 39 except that spherical graphitized carbon (6 parts by weight) was used as the conductive material of the positive electrode, and a clock ion primary battery for a lithium ion secondary battery was fabricated and implemented. Example 39 discharges and maps in the same manner. The axis of the inspection coordinate is the discharge valley rate (%), and the axis of the vertical coordinate is the discharge voltage (V). As a result, the pattern has a minimum value and a maximum value in the direction in which the discharge permittivity increases. As shown in Table 10, the difference between the minimum value and the maximum value was 0.33 V. The minimum value is 2 80 V. When the discharge capacity is constant, the difference between the minimum value and the discharge voltage (ΔΥ) is 0.30 ν. If the displayed voltage is abrupt, please read the precautions on the back first and then fill in this page. Scripture Book-Ministry of Education V: · Hui ... Finance. Industry, Bureau, Employee Cooperative Cooperatives Printed on this paper Standards applicable to Chinese National Standard (CNS) A4 (210 X 297 mm) 53 311440

492207 V. Description of invention (54) Decline. At the same time as in Example 39, the discharge capacity retention rate (%) and the intermediate voltage (V) were calculated (Table 10). Comparative Example 29 In the same manner as in Example 39, except that carbon black (1 part by weight) having a particle size of 0 "Vm was used alone as a conductive material to obtain a positive electrode, a lithium ion secondary battery was produced. The obtained lithium ion secondary battery was discharged and graphed in the same manner as in Example 39, wherein the horizontal axis is the discharge permittivity and the vertical axis is the discharge voltage (V). As a result, as in Comparative Example 28, the pattern showed a minimum value and a maximum value in the direction in which the discharge permittivity increased. As shown in Table 10, the difference (Δνΐ) between the minimum value and the maximum value was 0.28 v. The minimum value is 29 volts. When the discharge capacity ratio is 0%, the difference between the minimum value and the discharge voltage (ΔV2) is 0.60 V. As in Comparative Example 28, the display voltage suddenly drops. At the same time as in Example 39, the discharge capacity retention rate (%) and the intermediate voltage (v) were calculated (Table 10). Comparative Example 30 In the same manner as in Example 39, except that an average particle size of 18 / zm and a specific surface area of 0.20 m2 / g (measured by SALD-3000J) and [20 / (average particle size X specific surface area)] were used alone. A LiCo02 active material (91 parts by weight) having a value of 5.6 was used as a positive electrode active material to obtain a positive electrode, and a lithium ion secondary battery was prepared. The obtained chain ion secondary battery was discharged in the same manner as in Example 39, but it could not be mapped without discharging. Γ% Please read the notes on the back before filling in this page} Order · Printed by the Intellectual Property Bureau of the Ministry of Economic Affairs, Consumer Cooperatives This paper is printed in accordance with China National Standard (CNS) A4 (210 X 297 mm) 54 311440 492207 A7 B7 5 Description of the invention (55) Table 10 Example 39 Comparative Example 28 Comparative Example 29 Comparative Example 30 Δν ^ ν) No minimum value 0.33 0.28 Impossible discharge AV2 (v) 0.30 0.60 minimum value (V) 2.80 2.90 median value (V) 3,20 2.83 2.91 Impossible discharge capacity retention rate (%) 94 36 52 Impossible discharge is shown in Table 10, compared with the lithium ion secondary batteries of Comparative Examples 28 to 30, the lithium ion secondary batteries of Examples It can suppress the sudden drop of discharge voltage at extremely low temperature, and can also suppress the decrease of discharge capacitance (mAh) and intermediate voltage. This application is based on Japanese applications Nos. 133497/1999, 219326/1999, 223089/1999 '238785/1999, 290300/1999 and 324602/1999, the contents of which are incorporated herein by reference. -------------- Install --- (Please read the precautions on the back before filling out this page)-. Line · Ministry of Economic Affairs China National Standard (CNS) A4 (210 X 297 mm) 55 311440

Claims (1)

% 21 2 9 4 $ 1 Dazheng, L '$ 上 二 /.mXj No. 89109084 Patent Application Amendment to Patent Scope (January 8, 91) L A granular Li-transition metal composite oxide, the ratio The surface area (m2 / g) and average particle size 0m) satisfy the following formula: 7 $ [20 / (specific surface area X average particle size)] $ 9, wherein the transition metal compound includes cobalt, or cobalt and at least one transition metal. 2. The granular Li-transition metal composite oxide 'according to item 1 of the scope of the patent application has an average particle size of 10 / zm to 25 / zm. 3. Li-transition metal composite oxides such as those in the patent application No. 丨 or 2 are obtained by heat-treating Li-transition metal composite oxide particles at a high temperature of 400 to 750 ° C for 0.5 to 50 hours. 4. If the Li-transition metal composite oxide in item 3 of the scope of the patent application, the lithium compound and the transition metal compound are mixed at a lithium: transition metal atomic ratio of 1: 1 to 0.8: 1; The mixture is heated in the atmosphere at a temperature of 700 to 2000C for 3 to 50 hours; and the obtained reaction product is pulverized. Printed by the Staff Welfare Committee of the Central Standards Bureau of the Ministry of Economic Affairs H3 5.-A positive electrode active material for non-aqueous electrolyte secondary batteries, which features L transition metals such as any one of the scope of patent applications 1 to 4 Compound oxide. 6. A lithium-ion secondary battery characterized by including a positive electrode active material as described in item 5 of the patent application. 7 · —A kind of positive electrode active material composition, including at least one active material composed of transition metal compound oxygen compound, the average particle size of which is not less than 10511440 This paper size is applicable to China National Standard (CNS) A4 (210 X 297 mm) ) 492207-H3 / zm; — a granular conductive carbon material with a particle size not smaller than K3 "m; and a granular conductive carbon material with a particle size not larger than 2 // 111, where the transition metal compound includes With at least one transition metal. 8. The positive electrode active material composition according to item 7 of the scope of patent application, wherein the content of the granular conductive carbon material having a particle size of not more than 2 / zm is not less than 3 / zm of the granular conductive carbon material having a particle size of 1QQ by weight. In terms of amount to 200 parts by weight. 9. A composition of a positive electrode active material 'including at least one positive electrode active material composed of a Li-transition metal composite oxygen compound comprising cobalt or cobalt and at least one transition metal, the average particle size of which is not less than 10 V m; A conductive carbonaceous material having a particle size of not less than 3 // m; and a fibrous conductive carbon material having an aspect ratio of 3 or more and a fiber diameter of not more than 2 # m. 10. The positive electrode active material composition according to item 9 of the application, wherein the content ratio of the fibrous conductive material is 1 to 200 parts by weight for 100 parts by weight of the granular conductive material. Printed by the Staff Welfare Committee of the Central Standards Bureau of the Ministry of Economic Affairs. 11. The positive electrode active material according to any one of the 7th to 10th scope of the patent application. Composition 'wherein the Li-transition metal composite oxide is a Li_co type composite oxide. 12. A kind of primary ion battery, characterized in that it includes a positive electrode active material composition such as the one in the scope of the patent application. 13.—A kind of primary ion battery includes graphitization with a specific surface area of not more than 20 m2 / g, a lattice plane (d002) interval of not more than 0.338〇11111, and a crystallite size (Lc) of not less than 30 nm. Carbon made of negative electrode This paper size is applicable to Chinese National Standard (CNS) A4 specification (210 X 297 mm) JU44U active material and includes ethylene carbonate, propylene carbonate, dimethyl carbonate and selected from the group consisting of diethyl carbonate and carbonic acid A group of ethyl methyl esters to the electrolyte mixed solvent. 14. The lithium ion secondary battery according to item 13 of the patent application, wherein the mixed solvent includes the member having a proportion of 25% by volume to 50% by volume and a proportion of 4% by volume to 20% by volume of ethylene carbonate. It is propylene carbonate of 3% to 17% by volume, and dimethyl carbonate in a proportion of more than 40% by volume and not more than 60% by volume. 15. A lithium ion secondary battery as claimed in item 13 or µ, wherein the positive electrode active material includes a Li-Co type composite oxide. 16. The lithium-ion secondary battery according to item 15 of the application, wherein the Li-Co type composite oxide is Lico002. 17. · A clock ion secondary battery, including (1) a positive electrode active material, which is composed of granular Li-transition metal composite oxides having an average particle size of not less than 0 V m, where [2〇 / (average particle size X (Specific surface area)] = 7-9; Printed by the Staff Welfare Committee of the Central Standards Bureau of the Ministry of Economic Affairs (ii) Conductive substances, which are granular conductive substances with a particle size of not less than 3 / zm and granular conductive substances with a particle size of not less than 2 / zm Mixture; or a mixture of granular conductive materials with a particle size of not less than 3 / zm and fibrous conductive materials with an aspect ratio of 3 or more and a fiber diameter of not more than 2 # m; (iii) a negative electrode active material Graphite carbon composed of graphitized carbon with a surface area of not less than 2.0 m2 / g, a lattice plane spacing of not less than 0.338 nm, and an axial direction (Lc) of a crystallite size of not less than 30 nm; and (iv) an electrolyte mixed solvent 'including ethyl carbonate Dilute ester, propylene carbonate 7ΓΠ40 This paper size applies Chinese National Standard (CNS) A4 specification (210 X 297 mm) ~~ ____________H3_ _ si, dimethyl carbonate and selected from the group consisting of diethyl carbonate and ethyl methyl carbonate At least one member of a group. 18. The lithium ion secondary battery according to item 17 of the scope of patent application, wherein the mixed solvent includes the member having a proportion of 25% by volume to 50% by volume and a proportion of 4% by volume to 20% by volume of ethylene carbonate. It is propylene carbonate of 3% to 17% by volume, and dimethyl carbonate in a proportion of 40% by volume or more and not more than 60% by volume of 0/0. 19. The clock ion secondary battery of item 18 in the patent scope of Shenyan, wherein the Li-transition metal composite oxide is a Li_C0 type composite oxide. 20 · —A clock ion secondary battery comprising an electrolyte mixed solvent including at least one member selected from the group consisting of diethyl carbonate and ethyl methyl carbonate in a proportion of 40% by volume to 50% by volume, A vinyl carbonate having a proportion of 4 to 10% by volume, a propyl carbonate having a proportion of 10 to 17% by volume, and a dimethyl carbonate having a proportion of 30 to 40% by volume. 21. The ion secondary battery as claimed in claim 20, further comprising a positive active material layer having a filling rate of 65% to 85% and a negative active material layer having a filling rate of 65% to 85%. Member of the Central Standards Bureau of the Ministry of Economic Affairs and the Welfare Committee printed 22 · —lithium ion secondary batteries, including (i) a positive electrode active material composed of granular Li-transition metal composite oxides, where [20 / (average particle size X (Specific surface area)] = 7_9; and (ii) conductive material, which is a mixture of granular conductive material having a particle size of not less than 3 / zm and granular conductive material having a particle size of not less than 2 // m; or a particle size of not less than 3 / The paper size of the zm granular conductive material and the fibrous conductive material with an aspect ratio of 3 or more and a fiber diameter not greater than 2 / zm is applicable to the Chinese National Standard (CNS) A4 specification (210 X 297 public love) ^ — J1I440--J 492207 mixture. 23. The lithium ion secondary battery according to item 22 of the application, wherein the Li_transition metal composite oxide is a Li_co type composite oxide. 24 · —A kind of clock ion secondary battery whose discharge permittivity is calculated on the horizontal axis as the discharge capacitance (100%) of 1C discharge at 20 ° C and the vertical coordinate when the ic discharge of _2oc is performed. The axis shows the backslash discharge curve with no minimum value in the coordinates of the discharge voltage, and shows a discharge capacitance of not less than 60% of the discharge capacitance at a discharge of 20 ° C at 1C. 25 · —A lithium ion secondary battery whose discharge permittivity in terms of _2 (rCi ic discharge, discharge capacity (100%) at 1C discharge at 20 ° C, and vertical axis for discharge The voltage coordinates show the discharge curve with the minimum value and the maximum value in the direction of increasing the discharge permittivity, where the difference between the minimum value and the maximum value is not greater than 0.1 V, and when the discharge permittivity is 0%, the minimum The difference between the value and the discharge voltage is not more than 0,3 V, and when discharged at 1C at -20 ° C, it shows no less than 60% of the discharge capacitance of the discharge capacitor at 20 ° C. Staff Welfare Committee, Central Standards Bureau, Ministry of Economic Affairs Printed 26 · —a kind of lithium ion secondary battery, when discharging at 1C at -20 ° C, the discharge permittivity calculated as the discharge capacitance (100%) of 1C discharging at 20 ° C and the vertical discharge rate The coordinate axis shows the discharge curve in which the first maximum value, the minimum value, and the second maximum value appear in the direction of increase in discharge permittivity, where the difference between the minimum value and the second maximum value is not greater than 0.1 V, and When the discharge capacity is 0%, the difference between the minimum value and the discharge voltage is not the same. At 0.3 V and 1C discharge at -20 ° C, it shows no less than 60% of the discharge capacity at 20 ° C discharge. III44U This paper size is applicable to China National Standard (CNS) A4 (210 x 297 mm) Love)