WO2011086690A1 - 正極活物質の評価方法 - Google Patents
正極活物質の評価方法 Download PDFInfo
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- WO2011086690A1 WO2011086690A1 PCT/JP2010/050429 JP2010050429W WO2011086690A1 WO 2011086690 A1 WO2011086690 A1 WO 2011086690A1 JP 2010050429 W JP2010050429 W JP 2010050429W WO 2011086690 A1 WO2011086690 A1 WO 2011086690A1
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- H—ELECTRICITY
- H01—ELECTRIC ELEMENTS
- H01M—PROCESSES OR MEANS, e.g. BATTERIES, FOR THE DIRECT CONVERSION OF CHEMICAL ENERGY INTO ELECTRICAL ENERGY
- H01M4/00—Electrodes
- H01M4/02—Electrodes composed of, or comprising, active material
- H01M4/36—Selection of substances as active materials, active masses, active liquids
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- H—ELECTRICITY
- H01—ELECTRIC ELEMENTS
- H01M—PROCESSES OR MEANS, e.g. BATTERIES, FOR THE DIRECT CONVERSION OF CHEMICAL ENERGY INTO ELECTRICAL ENERGY
- H01M4/00—Electrodes
- H01M4/02—Electrodes composed of, or comprising, active material
- H01M4/13—Electrodes for accumulators with non-aqueous electrolyte, e.g. for lithium-accumulators; Processes of manufacture thereof
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- H—ELECTRICITY
- H01—ELECTRIC ELEMENTS
- H01M—PROCESSES OR MEANS, e.g. BATTERIES, FOR THE DIRECT CONVERSION OF CHEMICAL ENERGY INTO ELECTRICAL ENERGY
- H01M10/00—Secondary cells; Manufacture thereof
- H01M10/05—Accumulators with non-aqueous electrolyte
- H01M10/052—Li-accumulators
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- H—ELECTRICITY
- H01—ELECTRIC ELEMENTS
- H01M—PROCESSES OR MEANS, e.g. BATTERIES, FOR THE DIRECT CONVERSION OF CHEMICAL ENERGY INTO ELECTRICAL ENERGY
- H01M4/00—Electrodes
- H01M4/02—Electrodes composed of, or comprising, active material
- H01M4/04—Processes of manufacture in general
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- H—ELECTRICITY
- H01—ELECTRIC ELEMENTS
- H01M—PROCESSES OR MEANS, e.g. BATTERIES, FOR THE DIRECT CONVERSION OF CHEMICAL ENERGY INTO ELECTRICAL ENERGY
- H01M4/00—Electrodes
- H01M4/02—Electrodes composed of, or comprising, active material
- H01M2004/021—Physical characteristics, e.g. porosity, surface area
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- H—ELECTRICITY
- H01—ELECTRIC ELEMENTS
- H01M—PROCESSES OR MEANS, e.g. BATTERIES, FOR THE DIRECT CONVERSION OF CHEMICAL ENERGY INTO ELECTRICAL ENERGY
- H01M4/00—Electrodes
- H01M4/02—Electrodes composed of, or comprising, active material
- H01M2004/026—Electrodes composed of, or comprising, active material characterised by the polarity
- H01M2004/028—Positive electrodes
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- H—ELECTRICITY
- H01—ELECTRIC ELEMENTS
- H01M—PROCESSES OR MEANS, e.g. BATTERIES, FOR THE DIRECT CONVERSION OF CHEMICAL ENERGY INTO ELECTRICAL ENERGY
- H01M10/00—Secondary cells; Manufacture thereof
- H01M10/42—Methods or arrangements for servicing or maintenance of secondary cells or secondary half-cells
- H01M2010/4292—Aspects relating to capacity ratio of electrodes/electrolyte or anode/cathode
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- H—ELECTRICITY
- H01—ELECTRIC ELEMENTS
- H01M—PROCESSES OR MEANS, e.g. BATTERIES, FOR THE DIRECT CONVERSION OF CHEMICAL ENERGY INTO ELECTRICAL ENERGY
- H01M4/00—Electrodes
- H01M4/02—Electrodes composed of, or comprising, active material
- H01M4/13—Electrodes for accumulators with non-aqueous electrolyte, e.g. for lithium-accumulators; Processes of manufacture thereof
- H01M4/139—Processes of manufacture
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- Y—GENERAL TAGGING OF NEW TECHNOLOGICAL DEVELOPMENTS; GENERAL TAGGING OF CROSS-SECTIONAL TECHNOLOGIES SPANNING OVER SEVERAL SECTIONS OF THE IPC; TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS
- Y02—TECHNOLOGIES OR APPLICATIONS FOR MITIGATION OR ADAPTATION AGAINST CLIMATE CHANGE
- Y02E—REDUCTION OF GREENHOUSE GAS [GHG] EMISSIONS, RELATED TO ENERGY GENERATION, TRANSMISSION OR DISTRIBUTION
- Y02E60/00—Enabling technologies; Technologies with a potential or indirect contribution to GHG emissions mitigation
- Y02E60/10—Energy storage using batteries
Definitions
- the present invention relates to a method for evaluating a positive electrode active material.
- the present invention relates to a method for evaluating a positive electrode active material used in a lithium-ion secondary battery.
- Known positive electrode active materials used for lithium ion secondary batteries include composite oxides of lithium and transition metals such as LiCoO 2 , LiNiO 2 , LiMn 2 O 4 , and LiMnO 2 .
- International Publication No. 05/020354 (WO2005 / 020354) includes a first composite oxide powder having a high compressive fracture strength with respect to a lithium nickel cobalt manganese composite oxide powder for a lithium secondary battery positive electrode having a specific composition. It has been proposed to form a positive electrode having a high filling property synergistically by using the second composite oxide powder having a low compressive fracture strength in combination at a specific ratio. This gives a positive electrode with a synergistically large volumetric capacity density, and the large volumetric capacity of such a positive electrode has other characteristics required by the positive electrode, such as volumetric capacity density, safety, cycle characteristics, and large current discharge characteristics. It is said that it will be achieved without harming.
- a nickel / cobalt / manganese salt aqueous solution, an alkali metal hydroxide aqueous solution, and an ammonium ion supplier are supplied to the reaction system continuously or intermittently, respectively.
- the reaction is allowed to proceed while maintaining the temperature of the reaction system at a substantially constant temperature within the range of 30 to 70 ° C. and maintaining the pH at a substantially constant value within the range of 10 to 13.
- nickel-cobalt-manganese composite hydroxide aggregated particles in which primary particles obtained by folding nickel-cobalt-manganese composite hydroxide are aggregated to form secondary particles are synthesized.
- a lithium / nickel / cobalt / manganese-containing composite oxide is proposed, which is obtained by dry-mixing at least the composite oxyhydroxide and a lithium salt and firing the mixture in an oxygen-containing atmosphere.
- in-vehicle lithium-ion secondary batteries require battery performance that simultaneously satisfies the charge / discharge capacity according to the distance traveled by the car, the cycle characteristics according to the service life of the car, and the output characteristics for driving the car. It is done.
- the positive electrode active material of a lithium ion secondary battery for in-vehicle use is required to have such performance that the battery performance of the lithium ion secondary battery is exhibited.
- the positive electrode active material is evaluated by paying attention to the compressive fracture strength.
- the compression fracture strength is an appropriate evaluation index as a condition for simultaneously satisfying the above-described charge / discharge capacity, cycle characteristics, and output characteristics.
- the present inventor has conducted intensive studies on a positive electrode active material containing a lithium transition metal composite oxide in order to improve the battery performance of a lithium ion secondary battery such as charge / discharge capacity, cycle characteristics, and output characteristics.
- the inventor focuses attention on the specific surface area of the positive electrode active material in order to improve battery performance.
- the specific surface area indicates the surface area per unit weight of the positive electrode active material.
- the reaction area per unit weight is large, and it is considered that the reactivity of the positive electrode active material is improved.
- the present invention proposes a novel method for evaluating a positive electrode active material used in a lithium ion secondary battery.
- the positive electrode active material evaluation method includes a density ratio calculation step for obtaining a ratio between the apparent density Da of the positive electrode active material and the theoretical density Db of the positive electrode active material.
- the ratio obtained in the density ratio calculation step indicates the density of the positive electrode active material, and by evaluating the positive electrode active material based on the ratio, for example, a positive electrode active material having desired performance is obtained. Can do.
- the apparent density Da may be a density measured by a gas displacement pycnometer.
- the theoretical density Db may be a density (Dbm / Dbv) obtained by dividing the mass Dbm per unit cell volume of the positive electrode active material by the unit cell volume Dbv of the positive electrode active material.
- a method for manufacturing a lithium ion secondary battery including a positive electrode active material is a step of confirming that the ratio of the apparent density Da of the positive electrode active material and the theoretical density Db of the positive electrode active material is equal to or higher than a predetermined reference value. It is good to have. Thereby, since the positive electrode active material used for a lithium ion secondary battery can be evaluated appropriately, the performance of a lithium ion secondary battery can be improved.
- a predetermined reference value may be 0.90 for the ratio (Da / Db) between the apparent density Da of the positive electrode active material and the theoretical density Db of the positive electrode active material.
- the positive electrode active material for the lithium ion secondary battery may have a ratio (Da / Db) of the apparent density Da to the theoretical density Db (Da / Db) ⁇ 0.90.
- a positive electrode active material in which the ratio (Da / Db) of the apparent density Da to the theoretical density Db (Da / Db) ⁇ 0.90 is used as the positive electrode active material. Good.
- FIG. 1 is a schematic view showing a powder of a lithium transition metal composite oxide.
- FIG. 2 is a schematic view showing primary particles of a lithium transition metal composite oxide.
- FIG. 3 is a cross-sectional view of secondary particles of a lithium transition metal composite oxide.
- FIG. 4A is a process diagram of the measurement principle of a gas displacement pycnometer.
- FIG. 4B is a process diagram of the measurement principle of the gas displacement pycnometer.
- FIG. 4C is a process diagram of the measurement principle of the gas displacement pycnometer.
- FIG. 5 is a cumulative distribution diagram of the particle diameter of the positive electrode active material.
- FIG. 6 is a graph showing a measurement result of an equivalent circuit fitting of a Cole-Cole plot in an AC impedance measurement of a lithium ion secondary battery.
- FIG. 7 is a schematic view of the lithium ion secondary battery according to the first embodiment.
- FIG. 8 is a schematic view of a lithium ion secondary battery according to the second embodiment.
- FIG. 9 is a schematic view of a lithium ion secondary battery according to the second embodiment.
- FIG. 10 is a schematic view of an assembled battery according to the third embodiment.
- FIG. 11 is a schematic diagram of a vehicle equipped with a lithium ion secondary battery as a power source.
- the positive electrode active material is mainly used for lithium ion secondary batteries.
- a positive electrode active material includes, for example, a lithium transition metal composite oxide.
- the lithium transition metal composite oxide include LiCoO 2 , LiNiO 2 , LiNi x Co y O 2 , LiMn 2 O 4 , and LiMnO 2 .
- lithium transition metal composite oxide examples include general formula (I): Li 1 + m Ni p Co q Mn r M 1 s O 2 (I); The lithium nickel cobalt manganese complex oxide represented by these is included.
- M 1 is B, V, Mg, Al, Sr, Ti, Zr, Mo, Nb, W, Cr, Fe, Cu, Zn, Ga, In, Sn, La and It is 1 type, or 2 or more types selected from the group which consists of Ce.
- 0 ⁇ s ⁇ p, and s may be substantially 0 (that is, an oxide that does not substantially contain M 1 ).
- the said formula (I) points out the composition at the time of battery construction (in other words, composition of the positive electrode active material used for manufacture of a battery). This composition is generally the same as the composition at the time of complete discharge of the battery.
- Such a lithium transition metal composite oxide typically forms a hexagonal close-packed structure crystal and forms fine particles (primary particles) having a layered structure. Further, secondary particles in which such fine particles (primary particles) are aggregated are formed.
- the positive electrode active material evaluation method according to this embodiment can be suitably applied to, for example, a positive electrode active material containing a closed pore.
- the positive electrode active material is not limited to the examples given above, and is not necessarily limited to the lithium transition metal composite oxide.
- a lithium phosphate compound for example, lithium iron phosphate (LiFePO 4 ) is also included.
- the crystal structure of the positive electrode active material is not limited to the hexagonal close-packed structure.
- LiMn 2 O 4 is a so-called
- the evaluation object of the positive electrode active material evaluation method includes LiMn 2 O 4.
- the positive electrode active material to which the positive electrode active material evaluation method is applied includes lithium ion.
- Various positive electrode active materials used for secondary batteries are included.
- FIG. 1 is a schematic view showing a powder of a lithium transition metal composite oxide.
- FIG. 2 shows primary particles of a lithium transition metal composite oxide.
- FIG. 3 is a cross-sectional view of secondary particles of a lithium transition metal composite oxide. As shown in FIG.
- the lithium transition metal composite oxide 100 aggregates to some extent to form primary particles 110. Further, the primary particles 110 are aggregated to form secondary particles 120. Further, the lithium transition metal composite oxide 100 is a powder in which the secondary particles 120 are aggregated. In the lithium transition metal composite oxide 100, for example, as shown in FIGS. 2 and 3, closed pores 130 (closed pores: spaces not connected to the outside) are formed in the powder in which the secondary particles 120 are assembled. There is a case.
- the present inventor considered that an index considering the presence of closed pores contained in the positive electrode active material is appropriate for more appropriately evaluating the positive electrode active material. Then, the present inventor proposes an index “density ratio” as an index considering the presence of such closed pores.
- the density ratio is a ratio (Da / Db) between the apparent density Da of the positive electrode active material and the theoretical density Db of the positive electrode active material.
- the density ratio is defined as (Da / Db), but substantially the same evaluation is possible even if the reciprocal number (Db / Da) is used as the density ratio.
- the positive electrode active material used for the lithium ion secondary battery is evaluated by the density ratio (Da / Db).
- the apparent density Da of the positive electrode active material is a density in which the closed pore 130 is regarded as the volume of the positive electrode active material when the closed pore 130 (space not connected to the outside) is formed inside. It is.
- the apparent density Da of the positive electrode active material can be obtained by, for example, a gas substitution pycnometer.
- the measurement method using the gas displacement pycnometer is a method in which the volume of the gas displaced by the positive electrode active material is considered to be equal to the volume of the positive electrode active material in the sealed system.
- FIG. 4A to FIG. 4C are process diagrams showing the process of the measurement principle of the gas displacement pycnometer.
- the gas displacement pycnometer 200 includes a sample chamber 216 and an expansion chamber 218 communicated by a pipe 214 having a valve 212.
- the volume V cell of the sample chamber 216 and the volume V exp of the expansion chamber 218 are assumed to be known.
- the valve 212 is opened to set the pressure in the system to Pa.
- the valve 212 is closed, the sample 220 (positive electrode active material) is charged into the sample chamber 216, the sample chamber 216 is filled with helium gas, and the pressure in the sample chamber 216 is increased to P1.
- volume V samp V cell ⁇ [V exp / ⁇ (P1 ⁇ Pa) / (P2 ⁇ Pa) ⁇ 1 ⁇ ] (II); Then, the mass of the sample 220 measured separately is divided by the volume V samp thus measured. Thereby, the density of the sample 220 can be obtained.
- gas can enter the depression 140 on the outer surface of the sample 220 connected to the outside.
- the volume of the sample 220 (positive electrode active material) can be evaluated excluding the part (for example, the depression 140) into which gas can enter.
- the sample 220 (positive electrode active material) has a closed pore 130 (closed pore: a space not connected to the outside)
- gas cannot reach the closed pore 130 from the outside.
- the closed pore 130 is regarded as the volume of the sample 220 (positive electrode active material).
- the density of the sample 220 is evaluated to be small according to the size of the closed pore 130.
- the density evaluated by regarding the closed pore 130 as the volume of the sample 220 (positive electrode active material) is referred to herein as “apparent density Da”.
- the apparent density Da is calculated using the gas displacement pycnometer described above. It should be noted that the apparent density Da is preferably measured by a method that can consider the closed pore 130 as a volume, and is not necessarily measured by a gas displacement pycnometer. For example, a method of measuring the volume by immersing the sample may be employed.
- the theoretical density Db of the positive electrode active material is a density calculated theoretically.
- the theoretical density Db of such a positive electrode active material can be determined based on, for example, the crystal structure and molecular weight.
- the crystal structure of the positive electrode active material can be known, for example, by analyzing by X-ray diffraction.
- the molecular weight of the positive electrode active material can be determined from, for example, a composition formula.
- the unit of the lattice volume V is cubic centimeter (cm 3 ), and “6.02 ⁇ 10 23 ” is an Avogadro constant.
- the molecular weight M is the molecular weight of the lithium transition metal composite oxide obtained from the composition formula of the lithium transition metal composite oxide, and “3 ⁇ molecular weight M” indicates the molecular weight included in the unit crystal structure.
- the following formula (III) shows a case where the crystal structure of the positive electrode active material is a hexagonal close-packed structure. If the crystal structure of the positive electrode active material changes, the calculation formula of the theoretical density Db of the positive electrode active material changes.
- the density ratio (Da / Db) is determined by a ratio between the apparent density Da of the positive electrode active material and the theoretical density Db of the positive electrode active material.
- the density ratio (Da / Db) is close to 1 if there is no closed space inside the positive electrode active material such as the closed pore 130, but is blocked inside the positive electrode active material such as the closed pore 130. The more space there is, the smaller the value. Therefore, the density ratio (Da / Db) is an index for measuring the density of the positive electrode active material.
- Such a positive electrode active material having a density ratio (Da / Db) close to 1 has a small number of closed pores 130, and it can be expected that the contribution to the battery performance is substantially increased as a whole.
- the positive electrode active material having a density ratio (Da / Db) close to 1 is considered to have a dense structure with few closed pores 130.
- Such a positive electrode active material is considered to have high durability against a load acting at the time of charge / discharge and improve cycle characteristics.
- the inventor can improve the performance of the positive electrode of the lithium ion secondary battery by confirming that the density ratio (Da / Db) of the positive electrode active material is equal to or higher than a predetermined reference value. And gained knowledge.
- the positive electrode active material evaluation method evaluates the positive electrode active material based on the newly devised index of density ratio (Da / Db). According to such a density ratio (Da / Db), a positive electrode active material having desired performance can be obtained.
- the density ratio is the ratio (Da / Db) between the apparent density Da of the positive electrode active material and the theoretical density Db of the positive electrode active material, but even if the reciprocal number (Db / Da) is adopted. Good.
- (Db / Da) is adopted as the density ratio, the value is close to 1 if there is no closed space inside the positive electrode active material such as the closed pore 130 (see FIG. 3). The larger the closed space in the positive electrode active material, the larger the value. Therefore, the density ratio (Db / Da) is an index for measuring the density of the positive electrode active material.
- the closed pore 130 can be regarded as a volume by using the gas displacement pycnometer described above, and the apparent density Da can be appropriately obtained.
- the theoretical density Db may be obtained by the density (Dbm / Dbv) obtained by dividing the mass Dbm per unit cell volume of the positive electrode active material by the unit cell volume Dbv of the positive electrode active material.
- the density ratio (Da / Db) can obtain an appropriate index corresponding to the size of the space closed inside the positive electrode active material such as the closed pore 130.
- Such a positive electrode active material evaluation method can be applied to a method of manufacturing a lithium ion secondary battery.
- the ratio of the apparent density Da of the positive electrode active material to the theoretical density Db of the positive electrode active material (density ratio (Da / Db)) is equal to or higher than a predetermined reference value. It is good to have the process of confirming that it is.
- the method of manufacturing a lithium ion secondary battery by having such a step, it is possible to selectively use a positive electrode active material having an appropriate ratio of the closed pore 130, and to provide an appropriate performance for the lithium ion secondary battery. Can be secured.
- the inventor selectively uses a positive electrode active material in which the ratio (Da / Db) of the apparent density Da to the theoretical density Db is (Da / Db) ⁇ 0.90,
- a lithium ion secondary battery is particularly suitable for an in-vehicle lithium ion secondary battery that requires high charge / discharge capacity, cycle characteristics, and output characteristics.
- composition in the column z1 indicates the composition ratio of nickel (Ni), cobalt (Co), and manganese (Mn) in the lithium nickel cobalt manganese composite oxide.
- the “added element” in the column z2 indicates the presence or absence of the added element.
- the column “z2” of “added element” is represented by “ ⁇ ”.
- Zr zirconia
- the “additive element” column z2 is represented by “Zr”.
- Zr zirconia
- “Li / Me” in the column z3 in Table 1 indicates the molar ratio of lithium (Li) to transition metal (Ni, Co, Mo) for each of samples a to i (lithium nickel cobalt manganese composite oxide).
- “Particle size D50” in the z4 column of Table 1 indicates the particle size D50 of each sample ai.
- the particle diameter D50 is defined as a particle diameter in which when the samples a to i are divided into a large side and a small side with a certain particle diameter, the large side and the small side are equivalent.
- FIG. 5 is a diagram showing a cumulative distribution of particle diameters of the positive electrode active material. As shown in FIG.
- the particle diameter D50 is equivalent to the particle diameter (median diameter) of 50% in the cumulative distribution of the particle diameter of the positive electrode active material.
- “BET” in the z5 column of Table 1 indicates the specific surface area of each sample ai.
- the specific surface area is measured by a gas adsorption method.
- nitrogen gas may be used as the adsorption gas.
- apparent density Da in the column z6 in Table 1 indicates the apparent density Da of each of the samples a to i.
- the apparent density Da is a measured value measured using a dry automatic densimeter “Acupic 1330” manufactured by Shimadzu Corporation.
- Theoretical density Db in the column z7 in Table 1 indicates the theoretical density Db of each of the samples a to i.
- the crystal structure of each sample ai was analyzed by X-ray diffraction, and the theoretical density Db of each sample ai was calculated based on the analysis.
- Density ratio (Da / Db)” in the column z8 of Table 1 indicates the density ratio (Da / Db) of each sample a to i.
- a value obtained by dividing “apparent density Da” in the z6 column by “theoretical density Db” in the z7 column is shown.
- a positive electrode active material sample, acetylene black as a conductive material, and PVDF are mixed with NMP so that the mass ratio of these materials is 89: 8: 3 and the solid content concentration (NV) is about 40% by mass.
- positive electrode mixture compositions corresponding to the respective samples a to i were prepared.
- positive electrode composite compositions were applied to both sides of a 15 ⁇ m-thick long aluminum foil (current collector) and dried to form a positive electrode mixture layer.
- the coating amount (based on solid content) of the composition was adjusted to be about 12.8 g / m 2 for both surfaces. In this way, sheet-like positive electrodes (positive electrode sheets) corresponding to the respective samples a to i were produced.
- aqueous active material composition (negative electrode).
- a composite composition was prepared. This composition was applied to both sides of a long copper foil (negative electrode current collector) having a thickness of about 15 ⁇ m and dried to form a negative electrode mixture layer. In this way, a sheet-like negative electrode (negative electrode sheet) was produced.
- the positive electrode sheet and the negative electrode sheet produced above were laminated together with two long separators (here, a porous polyethylene sheet was used), and the laminated sheet was wound in the longitudinal direction to form a wound electrode body.
- This electrode body was housed in an outer case together with a non-aqueous electrolyte to construct a 18650 type lithium ion secondary battery.
- a non-aqueous electrolyte a composition in which LiPF6 was dissolved at a concentration of 1 mol / L in a mixed solvent containing EC, DMC, and EMC at a volume ratio of 3: 3: 4 was used.
- the 18650 type lithium ion secondary battery was prepared under the same conditions except for the samples a to i used for the positive electrode active material.
- An appropriate conditioning process is performed on the lithium ion secondary battery constructed as described above.
- the conditioning process for example, a constant current charge for 3 hours at a charge rate of 1/10 C, a charge operation at a constant current up to 4.1 V at a charge rate of 1/3 C, and a discharge rate of 1/3 C
- This is an initial charge / discharge treatment in which the operation of discharging a constant current to 0 V is repeated 2 to 3 times.
- AC impedance measurement is performed under the conditions of a measurement temperature of 25 ° C., a measurement frequency range of 0.001 to 10,000 Hz, and an amplitude of 5 mV.
- FIG. 6 shows the measurement result of the equivalent circuit fitting of the Cole-Cole plot in the AC impedance measurement.
- DC resistance Rsol and reaction resistance Rct (initial reaction resistance) were obtained by equivalent circuit fitting of Cole-Cole plot in AC impedance measurement. The results are shown in the z9 column of Table 1.
- ⁇ Capacity maintenance ratio The conditioned battery is charged with a constant current of 1 C (here, 1 A) until the terminal voltage reaches 4.1 V under a temperature condition of 25 ° C., and then the total charging time reaches 2 hours. Charged at a constant voltage. The battery after CC-CV charging was held at 25 ° C. for 24 hours, and then discharged at a constant current of 1 C from 4.1 V to 3.0 V at 25 ° C. Subsequently, the battery was discharged at a constant voltage until the total discharge time was 2 hours, and the discharge capacity (initial capacity) was measured.
- 1 C here, 1 A
- Capacity maintenance rate (%) ⁇ (capacity after cycle) / (initial capacity) ⁇ ⁇ 100;
- Capacity retention rate (%) after the above 1000 cycles of charge / discharge was determined.
- the “reaction resistance increase rate after endurance” is closer to 1, indicating that the battery performance (particularly, cycle characteristics and output characteristics) of the lithium ion secondary battery at the initial stage is maintained.
- the “capacity maintenance ratio” indicates that the battery performance (charge / discharge capacity) of the lithium ion secondary battery at the initial stage is maintained as it approaches 100%.
- the density ratio (Da / Db) is, for example, compared to the specific surface area (BET), the initial reaction resistance (z9) and the post-endurance reaction resistance increase. Correlation with the rate (z10) and the capacity maintenance rate (z11) was observed.
- the inventor has found that when the density ratio (Da / Db) is 0.9 or more, the initial reaction resistance (z9), the post-endurance reaction resistance increase rate (z10), Remarkably good results were obtained for the capacity retention rate (z11). Therefore, by selectively using the positive electrode active material having a density ratio (Da / Db) ⁇ 0.90, the battery performance of the lithium ion secondary battery such as charge / discharge capacity, cycle characteristics, and output characteristics is improved. I think you can. Such a lithium ion secondary battery is particularly suitable for an in-vehicle lithium ion secondary battery that requires high charge / discharge capacity, cycle characteristics, and output characteristics.
- the evaluation method of the positive electrode active material which concerns on one Embodiment of this invention was demonstrated, the evaluation method of the positive electrode active material which concerns on this invention is not limited to said example.
- the calculation method of the density ratio (Da / Db), for example, how to obtain the apparent density Da and the theoretical density Db is not limited to the above-described example.
- the battery configuration is not particularly limited.
- a positive electrode mixture containing the positive electrode active material as a main component that is, a component occupying 50% by mass or more, typically a component occupying 75% by mass or more
- a lithium ion secondary battery including the positive electrode.
- a conductive metal material such as aluminum can be preferably employed as in the conventional general lithium secondary battery.
- the shape of the positive electrode current collector can be different depending on the shape of the battery constructed using the positive electrode, and is not particularly limited. For example, various shapes such as a rod shape, a plate shape, a sheet shape, a foil shape, and a mesh shape It can be.
- the technology disclosed herein includes a positive electrode for a lithium secondary battery in which a positive electrode mixture layer is provided on a sheet-shaped or foil-shaped current collector, and a lithium secondary battery including the positive electrode as a constituent element It can be preferably applied to.
- an electrode body (rolled electrode body) obtained by winding a sheet-like positive electrode and a negative electrode together with a sheet-like separator is typically a suitable non-aqueous electrolyte (typically May be a battery having a configuration housed in an outer case together with a liquid electrolyte (that is, an electrolytic solution).
- the outer shape of the battery is not particularly limited, and may be, for example, a rectangular parallelepiped shape, a flat shape, a cylindrical shape, or the like.
- the positive electrode mixture may contain optional components such as a conductive material and a binder (binder) in addition to the positive electrode active material (typically in particulate form).
- a conductive material the thing similar to the electrically conductive material used for the positive electrode of a common lithium secondary battery, etc. can be employ
- the conductive material include carbon materials such as carbon powder and carbon fiber, and conductive metal powder such as nickel powder.
- One kind selected from such conductive materials may be used alone, or two or more kinds may be used in combination.
- the carbon powder various carbon blacks (for example, acetylene black, furnace black, ketjen black), graphite powder, and the like can be used. Of these, acetylene black and / or furnace black can be preferably employed.
- the proportion of the positive electrode active material in the total positive electrode mixture is preferably about 50% by mass or more (typically 50 to 95% by mass), and usually about 70 to 95% by mass (eg, 75 to 90% by mass). ) Is more preferable.
- the ratio of the conductive material in the whole positive electrode mixture can be, for example, about 2 to 20% by mass, and is usually preferably about 2 to 15% by mass.
- the ratio of the binder to the whole positive electrode mixture can be, for example, about 1 to 10% by mass, and usually about 2 to 5% by mass.
- the operation for forming the positive electrode mixture layer on the positive electrode current collector is, for example, a positive electrode mixture composition in which the positive electrode active material and other optional components (conductive material, binder, etc.) are dispersed in an appropriate solvent.
- the composition typically a paste or slurry-like composition
- the solvent any of an aqueous solvent and a non-aqueous solvent can be used.
- a preferred example of the non-aqueous solvent is N-methyl-2-pyrrolidone (NMP).
- cellulose-based polymers such as carboxymethyl cellulose (CMC) and hydroxypropylmethyl cellulose (HPMC); polyvinyl alcohol (PVA); polytetrafluoroethylene (PTFE), tetrafluoroethylene -Fluorine resin such as hexafluoropropylene copolymer (FEP); vinyl acetate copolymer; rubber such as styrene butadiene rubber (SBR) and acrylic acid modified SBR resin (SBR latex); A dispersible polymer can be preferably employed.
- CMC carboxymethyl cellulose
- HPMC hydroxypropylmethyl cellulose
- PVA polyvinyl alcohol
- PTFE polytetrafluoroethylene
- FEP tetrafluoroethylene -Fluorine resin
- FEP hexafluoropropylene copolymer
- SBR styrene butadiene rubber
- SBR latex acrylic acid modified SBR resin
- polymers such as polyvinylidene fluoride (PVDF) and polyvinylidene chloride (PVDC) can be preferably used.
- PVDF polyvinylidene fluoride
- PVDC polyvinylidene chloride
- the polymer material illustrated above may be used for the purpose of exhibiting functions as a thickener and other additives of the composition in addition to the function as a binder.
- the operation of applying the positive electrode mixture composition to the sheet-like current collector can be suitably performed using a conventionally known appropriate coating apparatus (slit coater, die coater, comma coater, gravure coater, etc.).
- Appropriate amount of the positive electrode mixture composition is applied to a predetermined range of at least one side (typically both sides) of the current collector, dried, and then pressed in the thickness direction as necessary to achieve the desired properties.
- the sheet-like positive electrode (positive electrode sheet) is obtained.
- a conventionally known roll pressing method, flat plate pressing method, or the like can be appropriately employed.
- FIG. 7 shows a schematic configuration of the lithium ion secondary battery according to the first embodiment.
- the lithium ion secondary battery 10 has a configuration in which an electrode body 11 including a positive electrode 12 and a negative electrode 14 is housed in a battery case 15 having a shape capable of housing the electrode body together with a non-aqueous electrolyte (not shown).
- the battery case 15 includes a bottomed cylindrical case body 52 and a lid 54 that closes the opening.
- the lid 54 and the case body 52 are both made of metal and insulated from each other, and are electrically connected to the positive and negative current collectors 22 and 42, respectively. That is, in the lithium ion secondary battery 10, the lid body 54 also serves as a positive electrode terminal, and the case body 52 also serves as a negative electrode terminal.
- the electrode body 11 includes a positive electrode (positive electrode sheet) 12 in which a positive electrode mixture layer 24 including any positive electrode active material disclosed herein is provided on a long sheet-like positive electrode current collector 22, and a long sheet A negative electrode (negative electrode sheet) 14 having a negative electrode mixture layer 44 on a negative electrode current collector (for example, copper foil) 42 is wound together with two long sheet-like separators 13.
- the negative electrode active material constituting the negative electrode mixture layer 44 one kind or two or more kinds of materials conventionally used for lithium ion secondary batteries can be used without particular limitation.
- a particulate carbon material (carbon particles) including a graphite structure (layered structure) at least partially is mentioned. Any carbon material of a so-called graphitic material (graphite), a non-graphitizable carbonaceous material (hard carbon), an easily graphitizable carbonaceous material (soft carbon), or a combination of these materials is preferred.
- graphite particles such as natural graphite can be preferably used.
- the negative electrode active material is typically mixed with a binder and, if necessary, a conductive material, and a negative electrode mixture composition is applied to the negative electrode current collector 42 and dried, whereby a current collector is obtained.
- the negative electrode mixture layer 44 can be formed at a desired portion of 42.
- the binder and the conductive material the same material as the positive electrode layer can be used.
- the ratio of the negative electrode active material to the whole negative electrode mixture can be about 80% by mass or more (for example, 80 to 99% by mass), and about 90% by mass or more (for example, 90 to 99% by mass). %, More preferably 95 to 99% by mass).
- the ratio of the binder to the whole negative electrode mixture can be, for example, about 0.5 to 10% by mass, and usually about 1 to 5% by mass is preferable.
- the separator 13 that is used while being overlapped with the positive and negative electrode sheets 12 and 14 the same material as that of a conventional lithium ion secondary battery can be used.
- a porous resin sheet (film) made of a polyolefin resin such as polyethylene or polypropylene can be preferably used.
- the positive and negative electrode sheets 12, 14 overlap both the composite material layers 24, 44, and the composite material layer non-formation portion of both electrode sheets has one end and the other along the longitudinal direction of the separator 13. The positions are slightly shifted in the width direction so as to protrude from the end portions.
- the lid 54 and the case main body 52 are connected to the protruding portion.
- the same non-aqueous electrolytic solution conventionally used for lithium ion secondary batteries can be used without any particular limitation.
- a nonaqueous electrolytic solution typically has a composition in which a supporting salt is contained in a suitable nonaqueous solvent.
- the non-aqueous solvent include ethylene carbonate (EC), propylene carbonate (PC), dimethyl carbonate (DMC), diethyl carbonate (DEC), ethyl methyl carbonate (EMC), 1,2-dimethoxyethane, 1,2 -One or more selected from the group consisting of diethoxyethane, tetrahydrofuran, 1,3-dioxolane and the like can be used.
- Examples of the supporting salt (supporting electrolyte) include LiPF 6 , LiBF 4 , LiAsF 6 , LiCF 3 SO 3 , LiC 4 F 9 SO 3 , LiN (CF 3 SO 2 ) 2 , LiC (CF 3 SO 2). )
- a lithium salt such as 3 can be used.
- the lithium ion secondary battery 20 includes a flat rectangular container 21 (typically made of metal and may be made of resin).
- a wound electrode body 30 is accommodated in the container 21.
- the wound electrode body 30 of the present embodiment is wound by overlapping a positive electrode sheet 32, a negative electrode sheet 34, and two separators 33, 35 using the same material as that of the first embodiment.
- the positive electrode sheet 32, the negative electrode sheet 34, and the two separators 33, 35 are composed of one end portion along the longitudinal direction of the separators 33, 35 and the other end of the electrode sheets 32, 34. They are overlaid so that they protrude from the ends.
- the winding body of the positive electrode sheet 32, the negative electrode sheet 34, and the two separators 33 and 35 is crushed from a side surface direction.
- the wound electrode body 30 is formed in a flat shape that matches the shape of the container 21.
- the positive electrode terminal 84 and the negative electrode terminal 86 for external connection are electrically connected to the electrode sheets 32 and 34.
- the portions protruding from the separator 33 in the positive electrode mixture layer non-forming portions of the electrode sheets 32 and 34 are gathered together in the radial direction of the wound electrode body 30, and the positive electrode terminal 84 is gathered in the gathered portions.
- the negative electrode terminal 86 are connected (for example, welded).
- the wound electrode body 30 to which the terminals 84 and 86 are connected is accommodated in the container 21, and after supplying an appropriate nonaqueous electrolytic solution therein, the container 21 is sealed. Has been built.
- the same non-aqueous electrolyte as in the first embodiment can be used.
- FIG. 10 shows a schematic configuration of the assembled battery according to the third embodiment.
- the assembled battery 60 is constructed by using a plurality of batteries 20 according to the second embodiment (typically 10 or more, preferably about 10 to 30, for example, 20). These batteries (unit cells) 20 are arranged in a direction in which the wide surfaces of the container 21 face each other while inverting one by one so that the positive terminals 84 and the negative terminals 86 are alternately arranged. In other words, they are arranged so that the surfaces corresponding to the flat surfaces of the wound electrode body 30 accommodated in the container 21 are overlapped.
- cooling plates 61 are arranged between the single cells 20 arranged in this way and on both outer sides of the arranged cells.
- the cooling plate 61 is disposed in close contact with the container 21 of each unit cell 20.
- the cooling plate 61 functions as a heat radiating member for efficiently dissipating heat generated in each unit cell during use. It has a shape capable of introducing a cooling fluid (typically air) between the unit cells 20. Examples of the shape capable of introducing the cooling fluid include a shape in which a plurality of parallel grooves extending vertically from one side of the rectangular cooling plate 61 to the opposite sides are provided on the surface.
- a cooling plate made of metal having good thermal conductivity or lightweight and hard polypropylene or other synthetic resin can be used.
- a pair of end plates 68 are provided on the outer side of the cooling plate 61 arranged on both outsides of the unit cells 20 and the cooling plates 61 (hereinafter collectively referred to as “single cell group”). , 69 are arranged. In this way, the whole cell cell group and the end plates 68 and 69 arranged in the stacking direction of the cell 20 and the end plates 68 and 69 (hereinafter also referred to as “constrained bodies”) bridge between the end plates 68 and 69.
- the attached restraining band 71 for fastening is restrained with a prescribed restraining pressure P in the stacking direction of the restrained body (that is, the lateral direction with respect to the axis of the wound electrode body 30).
- the restraining band 71 is restrained so that a prescribed restraining pressure P is applied in the stacking direction.
- the restraint pressure P is preferably about 0.1 MPa to 10 MPa as the surface pressure received by the wide surface of the container 21.
- one positive terminal 84 and the other negative terminal 86 are electrically connected by a connector 67.
- the assembled battery 60 of the desired voltage is constructed
- a lithium secondary battery (typically a lithium ion secondary battery) provided by the technology disclosed herein exhibits excellent performance (low reaction resistance, high durability, etc.) as described above. Therefore, it can be used as a lithium secondary battery for various applications. For example, it can be suitably used as a power source for a motor (electric motor) mounted on a vehicle such as an automobile.
- a lithium ion secondary battery may be used in the form of an assembled battery 60 in which a plurality of such lithium ion secondary batteries are connected in series or in parallel as shown in FIG.
- a vehicle 1 including such a lithium ion secondary battery 20 (including a battery pack) as a power source can be provided.
- the vehicle 1 includes, for example, an automobile including an electric motor such as an automobile, particularly a hybrid automobile, an electric automobile, and a fuel cell automobile.
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Abstract
Description
正極活物質は、主としてリチウムイオン二次電池に用いられる。かかる正極活物質は、例えば、リチウム遷移金属複合酸化物を含んでいる。リチウム遷移金属複合酸化物には、LiCoO2、LiNiO2、LiNixCoyO2、LiMn2O4、LiMnO2などがある。
Li1+mNipCoqMnrM1 sO2 (I);
で表されるリチウムニッケルコバルトマンガン複合酸化物が含まれる。ここで、上記式(I)において、M1は、B,V,Mg,Al,Sr,Ti,Zr,Mo,Nb,W,Cr,Fe,Cu,Zn,Ga,In,Sn,La及びCeからなる群から選択される一種又は二種以上である。
かかる知見を基に、本発明者は、正極活物質をより適切に評価するには、正極活物質に含まれるクローズドポアの存在を考慮した指標が適当であると考えた。そして、本発明者は、かかるクローズドポアの存在を考慮した指標として「密度比」なる指標を提案する。ここで、密度比は、正極活物質の見かけ密度Daと、正極活物質の理論密度Dbとの比(Da/Db)を求めたものである。なお、ここでは、密度比を(Da/Db)と規定しているが、その逆数(Db/Da)を密度比としても実質的には同様の評価が可能である。この実施形態では、リチウムイオン二次電池に用いられる正極活物質は、かかる密度比(Da/Db)によって評価する。
正極活物質の見かけ密度Daは、図2に示すように、内部にクローズドポア130(外部とつながっていない空間)が形成されている場合に、クローズドポア130を正極活物質の体積とみなした密度である。かかる正極活物質の見かけ密度Daは、例えば、気体置換型ピクノメータによって求めることができる。ここで、気体置換型ピクノメータを用いて測定する方法は、密閉された系内において、正極活物質によって置換される気体の体積が正極活物質の体積に等しいとみなす方法である。図4Aから図4Cは、気体置換型ピクノメータの測定原理の工程を示す工程図である。
ここで、試料220の体積Vsampは、下記の式(II):
体積Vsamp=Vcell-[Vexp/{(P1-Pa)/(P2-Pa)-1}] (II);
そして、このようにして測定された体積Vsampによって、別に測定した試料220の質量を割る。これにより、試料220の密度を求めることができる。
次に、正極活物質の理論密度Dbを説明する。正極活物質の理論密度Dbは、理論上算出される密度である。かかる正極活物質の理論密度Dbは、例えば、結晶構造や分子量を基に求めることができる。ここで、正極活物質の結晶構造は、例えば、X線回析によって分析することによって知ることができる。また正極活物質の分子量は、例えば、組成式から求めることができる。かかる正極活物質の理論密度Dbは、例えば、正極活物質の単位格子体積当り質量Dbmを、正極活物質の単位格子体積Dbvで割った密度(Dbm/Dbv)で算出することができる。これを数式で示すと次の通りである。Db=(単位結晶格子当りの質量:Dbm)/(単位結晶格子の体積:Dbv)。
下記の式(III)~(V)により算出される。:
単位結晶格子当りの質量:Dbm(g)=3×分子量M/6.02×1023 (III);
単位結晶格子の体積:Dbv(cm3)=格子体積V×10-24 (IV);
正極活物質の理論密度Db(g/cm3)=Dbm/Dbv=
3×分子量M×1024/6.02×1023/格子体積V (V);
まず、正極活物質サンプルと、導電材としてのアセチレンブラックと、PVDFとを、これら材料の質量比が89:8:3となり且つ固形分濃度(NV)が約40質量%となるようにNMPと混合して、各サンプルa~iに対応する正極合材組成物を調製した。
上記で構築したリチウムイオン二次電池に適当なコンディショニング処理を行う。コンディショニング処理は、例えば、1/10Cの充電レートで3時間の定電流充電を行い、さらに1/3Cの充電レートで4.1Vまで定電流で充電する操作と、1/3Cの放電レートで3.0Vまで定電流放電させる操作とを2~3回繰り返す初期充放電処理である。かかるコンディショニング処理を行った後、測定温度25℃、測定周波数範囲0.001~10000Hz、振幅5mVの条件で交流インピーダンス測定を行う。図6は、当該交流インピーダンス測定におけるCole-Coleプロットの等価回路フィッティングの測定結果を示している。
上記コンディショニング後の電池を、25℃の温度条件下にて、端子間電圧が4.1Vとなるまで1C(ここでは1A)の定電流で充電し、続いて合計充電時間が2時間となるまで定電圧で充電した。かかるCC-CV充電後の電池を25℃に24時間保持した後、25℃において、4.1Vから3.0Vまで1Cの定電流で放電させた。続いて合計放電時間が2時間となるまで定電圧で放電させて放電容量(初期容量)を測定した。次いで、60℃において、3.0Vから4.1Vまで2Cの定電流にて充電する操作と、4.1Vから3.0Vまで2Cの定電流にて放電させる操作とを交互に1000サイクル繰り返した。かかる充放電サイクル後の電池を、25℃において4.1Vから3.0Vまで1Cの定電流で放電させ、続いて合計放電時間が2時間となるまで定電圧で放電させて、このときの放電容量(サイクル後容量)を測定した。そして、次式:
容量維持率(%)={(サイクル後容量)/(初期容量)}×100;
により、上記1000サイクルの充放電後における容量維持率(%)を求めた。
上記充放電サイクル後の電池につき、上記と同様に交流インピーダンス測定を行い、そのCole-Coleプロットから直流抵抗Rsol及び反応抵抗Rct(耐久後反応抵抗)を求めた。そして、耐久後反応抵抗の値を初期反応抵抗の値で除して耐久後反応抵抗上昇率を求めた。このようにして得られた耐久後反応抵抗上昇率を表1のz10欄に示している。
図7は、第1実施形態に係るリチウムイオン二次電池の概略構成を示している。このリチウムイオン二次電池10は、正極12及び負極14を具備する電極体11が、図示しない非水電解液とともに、当該電極体を収容し得る形状の電池ケース15に収容された構成を有する。電池ケース15は、有底円筒状のケース本体52と、上記開口部を塞ぐ蓋体54とを備える。蓋体54及びケース本体52はいずれも金属製であって相互に絶縁されており、それぞれ正負極の集電体22,42と電気的に接続されている。すなわち、このリチウムイオン二次電池10では、蓋体54が正極端子、ケース本体52が負極端子を兼ねている。
図8と図9は、第2実施形態に係るリチウムイオン二次電池の概略構成を示している。このリチウムイオン二次電池20は、扁平な角型形状の容器21(典型的には金属製であり、樹脂製であってもよい。)を備える。この容器21の中に捲回電極体30が収容されている。本実施形態の捲回電極体30は、第一実施形態と同様の材料を用いてなる正極シート32、負極シート34及び二枚のセパレータ33、35が重ね合わされて捲回されている。この際、正極シート32、負極シート34及び二枚のセパレータ33、35は、両電極シート32,34の合材層非形成部がセパレータ33、35の長手方向に沿う一方の端部と他方の端部からそれぞれはみ出すように重ね合わされている。そして、正極シート32、負極シート34及び二枚のセパレータ33、35の捲回体を側面方向から押しつぶす。これによって、捲回電極体30は、容器21の形状に合わせた扁平形状に形成されている。
図10は、第3実施形態に係る組電池の概略構成を示している。この組電池60は、第2実施形態に係る電池20の複数個(典型的には10個以上、好ましくは10~30個程度、例えば20個)を用いて構築されている。これらの電池(単電池)20は、それぞれの正極端子84及び負極端子86が交互に配置されるように一つずつ反転させつつ、容器21の幅広な面が対向する方向に配列されている。換言すれば、容器21内に収容される捲回電極体30の扁平面に対応する面を重ね合わせるように配列されている。また、このように配列された各単電池20間及び当該配列された両外側には、冷却板61が配置されている。冷却板61は各単電池20の容器21に密接した状態で配置されている。この冷却板61は、使用時に各単電池内で発生する熱を効率よく放散させるための放熱部材として機能する。単電池20間に冷却用の流体(典型的には空気)を導入可能な形状を有する。冷却用の流体を導入可能な形状としては、例えば、長方形状の冷却板61の一辺から垂直に延びて対向する辺に至る複数の平行な溝が表面に設けられた形状が挙げられる。かかる冷却板61としては、例えば、熱伝導性の良い金属製もしくは軽量で硬質なポリプロピレンその他の合成樹脂製の冷却板を用いることができる。
11 電極体
12 正極シート
13 セパレータ
14 負極シート
15 電池ケース
20 リチウムイオン二次電池
21 容器
22 集電体(正極集電体)
24 正極合材層
30 捲回電極体(電極体)
32 正極シート
33、35 セパレータ
34 負極シート
42 負極集電体
44 負極合材層
52 ケース本体
54 蓋体
60 組電池
61 冷却板
67 接続具
68,69 エンドプレート
71 拘束バンド
72 ビス
84 正極端子
86 負極端子
100 リチウム遷移金属複合酸化物
110 一次粒子
120 二次粒子
130 クローズドポア
140 窪み
200 気体置換型ピクノメータ
212 バルブ
214 配管
216 試料室
218 膨張室
220 試料
Rct 反応抵抗
Rsol 直流抵抗
Vcell 試料室の体積
Vexp 膨張室の体積
Vsamp 試料の体積
Claims (7)
- リチウムイオン二次電池に用いられる正極活物質を評価する方法であって、
前記正極活物質の見かけ密度Daと、前記正極活物質の理論密度Dbとの比を求める密度比算出工程を有する、正極活物質の評価方法。 - 前記見かけ密度Daは気体置換型ピクノメータによって測定された密度である、請求項1に記載の正極活物質の評価方法。
- 前記理論密度Dbは、前記正極活物質の単位格子体積当り質量Dbmを、前記正極活物質の単位格子体積Dbvで割った密度(Dbm/Dbv)である、請求項1又は2に記載された正極活物質の評価方法。
- 正極活物質を含むリチウムイオン二次電池の製造方法であって、
前記正極活物質の見かけ密度Daと、前記正極活物質の理論密度Dbとの比が、予め定められた基準値以上であることを確認する工程を有する、リチウムイオン二次電池の製造方法。 - 前記正極活物質の見かけ密度Daと、前記正極活物質の理論密度Dbとの比(Da/Db)に対して、予め定められた基準値が0.90である、請求項4に記載されたリチウムイオン二次電池の製造方法。
- 見かけ密度Daと理論密度Dbとの比(Da/Db)が、(Da/Db)≧0.90である、リチウムイオン二次電池用の正極活物質。
- 正極活物質を含むリチウムイオン二次電池において、
前記正極活物質として、見かけ密度Daと理論密度Dbとの比(Da/Db)が、(Da/Db)≧0.90である正極活物質が用いられた、リチウムイオン二次電池。
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US13/521,241 US8765007B2 (en) | 2010-01-15 | 2010-01-15 | Method of evaluating positive electrode active material |
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Cited By (7)
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---|---|---|---|---|
WO2014034151A1 (ja) * | 2012-09-03 | 2014-03-06 | 三洋電機株式会社 | 充電装置、二次電池の充電方法、二次電池の製造方法 |
JP2015023021A (ja) * | 2013-07-19 | 2015-02-02 | 三星エスディアイ株式会社Samsung SDI Co.,Ltd. | リチウム二次電池用正極活物質、その製造方法、これを含む正極およびリチウム二次電池 |
WO2016129361A1 (ja) * | 2015-02-12 | 2016-08-18 | Jx金属株式会社 | リチウムイオン電池用正極活物質、リチウムイオン電池用正極、リチウムイオン電池、及び、リチウムイオン電池用正極活物質の製造方法 |
JP2018098205A (ja) * | 2016-12-08 | 2018-06-21 | 三星エスディアイ株式会社Samsung SDI Co., Ltd. | リチウム二次電池用ニッケル系活物質、その製造方法、及びそれを含む正極を含んだリチウム二次電池 |
US11302919B2 (en) | 2016-07-20 | 2022-04-12 | Samsung Sdi Co., Ltd. | Nickel-based active material for lithium secondary battery, method of preparing the same, and lithium secondary battery including positive electrode including the nickel-based active material |
US11456458B2 (en) | 2016-12-08 | 2022-09-27 | Samsung Sdi Co., Ltd. | Nickel-based active material precursor for lithium secondary battery, preparing method thereof, nickel-based active material for lithium secondary battery formed thereof, and lithium secondary battery comprising positive electrode including the nickel-based active material |
US11569503B2 (en) | 2016-07-20 | 2023-01-31 | Samsung Sdi Co., Ltd. | Nickel-based active material for lithium secondary battery, method of preparing the same, and lithium secondary battery including positive electrode including the nickel-based active material |
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US11498446B2 (en) * | 2020-01-06 | 2022-11-15 | Ford Global Technologies, Llc | Plug-in charge current management for battery model-based online learning |
WO2021195961A1 (zh) * | 2020-03-31 | 2021-10-07 | 宁德新能源科技有限公司 | 正极材料、包括其的电化学装置和电子装置及制备该正极材料的方法 |
Citations (5)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
JPH1145711A (ja) * | 1997-05-28 | 1999-02-16 | Showa Denko Kk | 正極活物質及びそれを用いた非水二次電池 |
WO2001004975A1 (fr) * | 1999-07-07 | 2001-01-18 | Showa Denko K.K. | Matiere active de plaque positive, procede de fabrication de celle-ci et de cellules secondaires |
JP2001085006A (ja) * | 1999-09-14 | 2001-03-30 | Toyota Central Res & Dev Lab Inc | リチウム二次電池正極活物質用リチウムニッケル複合酸化物およびそれを用いたリチウム二次電池 |
JP2003229124A (ja) * | 2002-01-31 | 2003-08-15 | Hitachi Metals Ltd | 非水系リチウム二次電池用正極活物質とその製造方法及びそれを用いた非水系リチウム二次電池 |
JP2005005105A (ja) * | 2003-06-11 | 2005-01-06 | Hitachi Ltd | 正極材料とその製造方法及びリチウム二次電池 |
Family Cites Families (7)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
JPH10106561A (ja) | 1996-09-26 | 1998-04-24 | Nec Corp | 正極活物質およびそれを用いた有機電解液二次電池 |
CN1312792C (zh) | 2003-03-14 | 2007-04-25 | 清美化学股份有限公司 | 锂二次电池用正极活性物质粉末 |
KR100694567B1 (ko) | 2003-04-17 | 2007-03-13 | 세이미 케미칼 가부시끼가이샤 | 리튬-니켈-코발트-망간 함유 복합 산화물 및 리튬 이차전지용 양극 활성물질용 원료와 그것들의 제조방법 |
CN100334758C (zh) | 2003-08-21 | 2007-08-29 | 清美化学股份有限公司 | 锂二次电池用的正极活性物质粉末 |
JP2008152925A (ja) * | 2006-12-14 | 2008-07-03 | Sumitomo Electric Ind Ltd | 電池構造体およびそれを用いたリチウム二次電池 |
JP2008153017A (ja) | 2006-12-15 | 2008-07-03 | Ise Chemicals Corp | 非水電解液二次電池用正極活物質 |
US20080206641A1 (en) * | 2007-02-27 | 2008-08-28 | 3M Innovative Properties Company | Electrode compositions and electrodes made therefrom |
-
2010
- 2010-01-15 WO PCT/JP2010/050429 patent/WO2011086690A1/ja active Application Filing
- 2010-01-15 KR KR1020127021309A patent/KR101488576B1/ko active IP Right Grant
- 2010-01-15 JP JP2011549825A patent/JP5696904B2/ja active Active
- 2010-01-15 CN CN201080061470.9A patent/CN102714305B/zh active Active
- 2010-01-15 US US13/521,241 patent/US8765007B2/en active Active
Patent Citations (5)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
JPH1145711A (ja) * | 1997-05-28 | 1999-02-16 | Showa Denko Kk | 正極活物質及びそれを用いた非水二次電池 |
WO2001004975A1 (fr) * | 1999-07-07 | 2001-01-18 | Showa Denko K.K. | Matiere active de plaque positive, procede de fabrication de celle-ci et de cellules secondaires |
JP2001085006A (ja) * | 1999-09-14 | 2001-03-30 | Toyota Central Res & Dev Lab Inc | リチウム二次電池正極活物質用リチウムニッケル複合酸化物およびそれを用いたリチウム二次電池 |
JP2003229124A (ja) * | 2002-01-31 | 2003-08-15 | Hitachi Metals Ltd | 非水系リチウム二次電池用正極活物質とその製造方法及びそれを用いた非水系リチウム二次電池 |
JP2005005105A (ja) * | 2003-06-11 | 2005-01-06 | Hitachi Ltd | 正極材料とその製造方法及びリチウム二次電池 |
Cited By (10)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
WO2014034151A1 (ja) * | 2012-09-03 | 2014-03-06 | 三洋電機株式会社 | 充電装置、二次電池の充電方法、二次電池の製造方法 |
JP2015023021A (ja) * | 2013-07-19 | 2015-02-02 | 三星エスディアイ株式会社Samsung SDI Co.,Ltd. | リチウム二次電池用正極活物質、その製造方法、これを含む正極およびリチウム二次電池 |
WO2016129361A1 (ja) * | 2015-02-12 | 2016-08-18 | Jx金属株式会社 | リチウムイオン電池用正極活物質、リチウムイオン電池用正極、リチウムイオン電池、及び、リチウムイオン電池用正極活物質の製造方法 |
JP2016149258A (ja) * | 2015-02-12 | 2016-08-18 | Jx金属株式会社 | リチウムイオン電池用正極活物質、リチウムイオン電池用正極、リチウムイオン電池、及び、リチウムイオン電池用正極活物質の製造方法 |
US11302919B2 (en) | 2016-07-20 | 2022-04-12 | Samsung Sdi Co., Ltd. | Nickel-based active material for lithium secondary battery, method of preparing the same, and lithium secondary battery including positive electrode including the nickel-based active material |
US11569503B2 (en) | 2016-07-20 | 2023-01-31 | Samsung Sdi Co., Ltd. | Nickel-based active material for lithium secondary battery, method of preparing the same, and lithium secondary battery including positive electrode including the nickel-based active material |
US11742482B2 (en) | 2016-07-20 | 2023-08-29 | Samsung Sdi Co., Ltd. | Nickel-based active material for lithium secondary battery, method of preparing the same, and lithium secondary battery including positive electrode including the nickel-based active material |
JP2018098205A (ja) * | 2016-12-08 | 2018-06-21 | 三星エスディアイ株式会社Samsung SDI Co., Ltd. | リチウム二次電池用ニッケル系活物質、その製造方法、及びそれを含む正極を含んだリチウム二次電池 |
US11309542B2 (en) | 2016-12-08 | 2022-04-19 | Samsung Sdi Co., Ltd. | Nickel-based active material for lithium secondary battery, preparing method thereof, and lithium secondary battery including positive electrode including the same |
US11456458B2 (en) | 2016-12-08 | 2022-09-27 | Samsung Sdi Co., Ltd. | Nickel-based active material precursor for lithium secondary battery, preparing method thereof, nickel-based active material for lithium secondary battery formed thereof, and lithium secondary battery comprising positive electrode including the nickel-based active material |
Also Published As
Publication number | Publication date |
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US8765007B2 (en) | 2014-07-01 |
JP5696904B2 (ja) | 2015-04-08 |
CN102714305A (zh) | 2012-10-03 |
KR101488576B1 (ko) | 2015-02-02 |
JPWO2011086690A1 (ja) | 2013-05-16 |
CN102714305B (zh) | 2015-05-27 |
KR20120118037A (ko) | 2012-10-25 |
US20130047721A1 (en) | 2013-02-28 |
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