WO2015033620A1 - 非水電解質二次電池及びその製造方法 - Google Patents
非水電解質二次電池及びその製造方法 Download PDFInfo
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- WO2015033620A1 WO2015033620A1 PCT/JP2014/063485 JP2014063485W WO2015033620A1 WO 2015033620 A1 WO2015033620 A1 WO 2015033620A1 JP 2014063485 W JP2014063485 W JP 2014063485W WO 2015033620 A1 WO2015033620 A1 WO 2015033620A1
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- H01M4/02—Electrodes composed of, or comprising, active material
- H01M4/36—Selection of substances as active materials, active masses, active liquids
- H01M4/48—Selection of substances as active materials, active masses, active liquids of inorganic oxides or hydroxides
- H01M4/485—Selection of substances as active materials, active masses, active liquids of inorganic oxides or hydroxides of mixed oxides or hydroxides for inserting or intercalating light metals, e.g. LiTi2O4 or LiTi2OxFy
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- H01M10/00—Secondary cells; Manufacture thereof
- H01M10/05—Accumulators with non-aqueous electrolyte
- H01M10/052—Li-accumulators
- H01M10/0525—Rocking-chair batteries, i.e. batteries with lithium insertion or intercalation in both electrodes; Lithium-ion batteries
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- H01M10/05—Accumulators with non-aqueous electrolyte
- H01M10/056—Accumulators with non-aqueous electrolyte characterised by the materials used as electrolytes, e.g. mixed inorganic/organic electrolytes
- H01M10/0564—Accumulators with non-aqueous electrolyte characterised by the materials used as electrolytes, e.g. mixed inorganic/organic electrolytes the electrolyte being constituted of organic materials only
- H01M10/0566—Liquid materials
- H01M10/0567—Liquid materials characterised by the additives
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- 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
- H01M10/056—Accumulators with non-aqueous electrolyte characterised by the materials used as electrolytes, e.g. mixed inorganic/organic electrolytes
- H01M10/0564—Accumulators with non-aqueous electrolyte characterised by the materials used as electrolytes, e.g. mixed inorganic/organic electrolytes the electrolyte being constituted of organic materials only
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- H01M10/0568—Liquid materials characterised by the solutes
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- H01M10/00—Secondary cells; Manufacture thereof
- H01M10/05—Accumulators with non-aqueous electrolyte
- H01M10/056—Accumulators with non-aqueous electrolyte characterised by the materials used as electrolytes, e.g. mixed inorganic/organic electrolytes
- H01M10/0564—Accumulators with non-aqueous electrolyte characterised by the materials used as electrolytes, e.g. mixed inorganic/organic electrolytes the electrolyte being constituted of organic materials only
- H01M10/0566—Liquid materials
- H01M10/0569—Liquid materials characterised by the solvents
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- 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
- H01M4/58—Selection of substances as active materials, active masses, active liquids of inorganic compounds other than oxides or hydroxides, e.g. sulfides, selenides, tellurides, halogenides or LiCoFy; of polyanionic structures, e.g. phosphates, silicates or borates
- H01M4/5825—Oxygenated metallic salts or polyanionic structures, e.g. borates, phosphates, silicates, olivines
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- 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
- H01M2004/027—Negative electrodes
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- H—ELECTRICITY
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- H01M—PROCESSES OR MEANS, e.g. BATTERIES, FOR THE DIRECT CONVERSION OF CHEMICAL ENERGY INTO ELECTRICAL ENERGY
- H01M2300/00—Electrolytes
- H01M2300/0017—Non-aqueous electrolytes
- H01M2300/0025—Organic electrolyte
- H01M2300/0028—Organic electrolyte characterised by the solvent
- H01M2300/0037—Mixture of solvents
- H01M2300/004—Three solvents
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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
- H01M4/48—Selection of substances as active materials, active masses, active liquids of inorganic oxides or hydroxides
- H01M4/483—Selection of substances as active materials, active masses, active liquids of inorganic oxides or hydroxides for non-aqueous cells
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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
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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
- Y02P—CLIMATE CHANGE MITIGATION TECHNOLOGIES IN THE PRODUCTION OR PROCESSING OF GOODS
- Y02P70/00—Climate change mitigation technologies in the production process for final industrial or consumer products
- Y02P70/50—Manufacturing or production processes characterised by the final manufactured product
Definitions
- the present invention relates to a non-aqueous electrolyte secondary battery and a manufacturing method thereof. More specifically, in a non-aqueous electrolyte secondary battery using titanium oxide as a negative electrode active material, it is possible to suppress gas generation and battery capacity reduction associated with use in a high-temperature environment, and excellent in low-temperature charge / discharge characteristics.
- the present invention relates to a secondary battery and a manufacturing method thereof.
- Non-aqueous electrolyte batteries that are charged and discharged by moving lithium ions between the negative electrode and the positive electrode have been actively researched and developed as high energy density batteries.
- lithium transition metal composite oxides are used as positive electrode active materials.
- Non-aqueous electrolyte batteries using a carbon-based material as a negative electrode active material have been commercialized and are frequently used in small portable devices and the like.
- non-aqueous electrolyte batteries will be used as power sources for power storage facilities and in-vehicle power sources such as HEVs by increasing the size and size of nonaqueous electrolyte batteries.
- HEVs in-vehicle power sources
- batteries are used in a wider temperature range than consumer applications.
- sufficient charge / discharge characteristics are required even at low temperatures, and reliability at high temperatures is required.
- Titanium oxide with a lithium ion storage potential of 1.2 V (vs. Li / Li + ) or more has a large difference in lithium ion storage potential from the metal lithium deposition potential. Even if it is performed, metallic lithium is essentially difficult to deposit. Further, for example, Li 4 Ti 5 O 12 has very little structural deterioration because there is almost no change in the unit cell of the crystal accompanying charge / discharge. Therefore, a battery using titanium oxide as a negative electrode active material is expected to have high safety and excellent battery characteristics, particularly cycle life characteristics.
- the above-described titanium oxide has a high lithium ion storage / release potential of 1.2 V (vs. Li / Li + ) or higher, unlike the case of carbon-based active materials, a stable protective film called an SEI film is formed on its surface.
- gas is generated due to the continuous reductive decomposition of the non-aqueous electrolyte.
- gas is easily generated when charging / discharging (high temperature cycle) is performed in a high temperature environment, and the battery capacity is reduced.
- the internal pressure of the battery will increase and the battery will swell, and the decrease in battery capacity will be accelerated, resulting in a decrease in life performance.
- Patent Document 2 discloses a non-aqueous electrolyte including a lithium-containing nickel composite oxide as a positive electrode, a lithium-containing titanium oxide as a negative electrode, and a cyclic carbonate and a chain carbonate in a specific ratio as a solvent in a non-aqueous electrolyte.
- a secondary battery is disclosed, and it is said that cycle characteristics can be improved by suppressing overdischarge.
- the electrolytic solution disclosed here is used, the low-temperature charge / discharge characteristics are not sufficient, and the gas generation is not sufficiently reduced when the cycle test is performed at a high temperature.
- Patent Document 3 discloses a non-aqueous electrolyte secondary comprising a positive electrode containing aluminum partially substituted lithium manganate, a negative electrode containing lithium titanate, and a non-aqueous electrolyte containing a cyclic carbonate and a chain carbonate.
- a nonaqueous electrolyte secondary battery in which the ratio of the cyclic carbonate contained in the solvent of the nonaqueous electrolyte solution is 25% by volume or less is disclosed, and the charge / discharge cycle performance is excellent in a wide temperature range from high temperature to low temperature. It is said that a non-aqueous electrolyte secondary battery showing can be provided.
- the low temperature characteristics could be improved to some extent, and the charge / discharge cycle test at 45 ° C. showed excellent characteristics.
- the cycle test was performed at a higher temperature such as 55 ° C. or higher, significant gas generation occurred.
- Patent Document 4 discloses a carbon-carbon double bond contained in the nonaqueous solvent in a nonaqueous electrolyte battery having a negative electrode having a negative electrode active material into which lithium ions are inserted and desorbed at a potential of 1.2 V or higher.
- the volume of carbonate ester not having 100 is 100, the volume of cyclic carbonate of the carbonate ester is a, the volume of dimethyl carbonate is b, the volume of ethyl methyl carbonate is c, and the volume of diethyl carbonate is d,
- a nonaqueous electrolyte battery characterized by simultaneously satisfying 0 ⁇ a ⁇ 30, 0 ⁇ b ⁇ 60, 0 ⁇ c ⁇ 100 and 0 ⁇ d ⁇ 10 is disclosed, and has excellent -30 ° C. low temperature output characteristics, Furthermore, it is said that a non-aqueous electrolyte battery with little deterioration in output characteristics even after high temperature storage can be provided.
- Non-aqueous electrolytes according to active materials used at the same time have been proposed (for example, Patent Document 5). Even if the non-aqueous electrolyte is a combination of a known solvent and a known electrolyte, additive, etc., depending on the combination, an unexpectedly excellent effect may be seen due to the interaction of these components, Further, since the effect varies depending on the active material species used at the same time, for example, due to a difference in the lithium ion storage potential, it is difficult for those skilled in the art to estimate what effect can be obtained.
- An object of the present invention is to provide a nonaqueous electrolyte secondary battery using a titanium oxide as a negative electrode active material, use in a high temperature environment, in particular, a reduction in gas generation accompanying repeated charge / discharge (high temperature cycle) in a high temperature environment, and a battery
- An object of the present invention is to provide a non-aqueous electrolyte secondary battery that can suppress a decrease in capacity and has excellent low-temperature charge / discharge characteristics.
- the present inventors have provided a negative electrode including an active material containing a titanium oxide having a lithium ion storage potential of 1.2 V (vs. Li / Li + ) or higher.
- the inventors have found that the above problems can be solved by making the composition of the non-aqueous electrolyte used in the non-aqueous electrolyte battery specific, and have reached the present invention.
- the present invention (1) includes a positive electrode, a negative electrode including an active material containing a titanium oxide having a lithium ion storage potential of 1.2 V (vs. Li / Li + ) or higher, a lithium salt, and a non-soluble material that dissolves the lithium salt.
- a non-aqueous electrolyte secondary battery comprising a non-aqueous electrolyte containing an aqueous solvent, wherein the non-aqueous solvent includes at least the following three types (a), (b), and (c): , (A) ethylene carbonate (b) cyclic carboxylic acid ester or cyclic carbonate having 4 or more carbon atoms (c) chain carbonate
- the lithium salt contains at least lithium hexafluorophosphate and lithium tetrafluoroborate
- the ethylene carbonate is 5 to 20% by volume of the whole non-aqueous solvent
- the non-aqueous electrolyte secondary battery has a lithium tetrafluoroborate concentration of 0.05 to 0.5 mol / liter with respect to the non-aqueous electrolyte.
- the a and the b Is a nonaqueous electrolyte secondary battery of (1) that satisfies b ⁇ a.
- the molar concentration of the lithium hexafluorophosphate in the nonaqueous electrolytic solution is 0.5 to 1.4 mol / liter, according to any one of (1) to (3).
- This is a non-aqueous electrolyte secondary battery.
- the solvent (b) contains a cyclic carbonate or cyclic carboxylic acid ester having a melting point of ⁇ 30 ° C. or less and a relative dielectric constant of 30 or more, and the solvent (c) has a melting point of
- the solvent (b) contains at least one selected from propylene carbonate, butylene carbonate, pentylene carbonate, ⁇ -butyrolactone and ⁇ -valerolactone, and the solvent (c)
- the present invention (7) is the nonaqueous electrolyte secondary battery according to any one of (1) to (6), wherein a charge capacity of the nonaqueous electrolyte secondary battery is regulated by a negative electrode.
- the titanium oxide may be spinel lithium titanate, ramsdellite lithium titanate, monoclinic titanate compound, monoclinic titanium oxide and lithium hydrogen titanate.
- the titanium oxide is composed of Li 4 + x Ti 5 O 12 , Li 2 + x Ti 3 O 7 , a titanate compound represented by the general formula H 2 Tin n O 2n + 1 , and bronze type titanium oxide.
- the nonaqueous electrolyte secondary battery according to any one of (1) to (8), which is selected. (X is a real number satisfying 0 ⁇ x ⁇ 3, and n is an even number of 4 or more.)
- the non-aqueous electrolyte further includes at least one selected from a dinitrile compound, vinylene carbonate, ethylene sulfite and 1,3-propane sultone.
- the nonaqueous electrolyte secondary battery according to any one of the above.
- the present invention (11) is the non-aqueous electrolyte secondary battery according to any one of (1) to (10), wherein the positive electrode active material is lithium iron phosphate.
- the present invention (12) includes a positive electrode, a negative electrode including an active material containing a titanium oxide having a lithium ion storage potential of 1.2 V (vs. Li / Li + ) or higher, a lithium salt, and a non-soluble lithium salt.
- a step of containing a nonaqueous electrolyte containing an aqueous solvent in an exterior member, sealing an opening of the exterior member to obtain a sealed secondary battery, and a step of charging the sealed secondary battery A non-aqueous electrolyte secondary battery manufacturing method, wherein the non-aqueous solvent includes at least the following three types (a), (b), and (c): (A) ethylene carbonate (b) cyclic carboxylic acid ester, or cyclic carbonate having 4 or more carbon atoms (c) chain carbonate
- the lithium salt contains at least lithium hexafluorophosphate and lithium tetrafluoroborate
- a nonaqueous electrolyte secondary battery in which ethylene carbonate is 5 to 20% by volume of the whole nonaqueous solvent and the lithium tetrafluoroborate concentration is 0.05 to 0.5 mol / liter with respect to the nonaqueous electrolyte. It is a manufacturing method.
- the present invention (13) includes a positive electrode, a negative electrode containing an active material containing a titanium oxide having a lithium ion occlusion potential of 1.2 V (vs. Li / Li + ) or higher, a lithium salt, and a non-dissolving lithium salt.
- the non-aqueous solvent includes at least the following three types (a), (b) and (c): (A) ethylene carbonate (b) cyclic carboxylic acid ester, or cyclic carbonate having 4 or more carbon atoms (c) chain carbonate
- the lithium salt contains at least lithium hexafluorophosphate and lithium tetrafluoroborate,
- the ethylene carbonate is 5 to 20% by volume of the whole non-aqueous solvent
- the lithium tetrafluoroborate concentration is 0.05 to 0.5 mol / liter with respect to the non-aqueous electrolyte. It is a manufacturing method of a nonaqueous electrolyte secondary battery.
- this invention (14) is the manufacturing method of the nonaqueous electrolyte secondary battery as described in (13) which performs the said storage by an open circuit.
- a non-aqueous electrolyte secondary battery using titanium oxide as a negative electrode active material use in a high temperature environment, particularly reduction of gas generation and battery capacity reduction accompanying a high temperature cycle is possible.
- the nonaqueous electrolyte secondary battery according to the present invention will be described in more detail.
- the nonaqueous electrolyte secondary battery 1 of the present invention includes a positive electrode 2, a negative electrode 3, a separator 4, a nonaqueous electrolyte solution 5, and an exterior member 6 as shown in FIGS. 1 and 2.
- the negative electrode 3 includes at least a negative electrode current collector 3a and a negative electrode active material layer 3b.
- the negative electrode active material layer is formed on one side or both sides of the negative electrode current collector.
- the negative electrode active material layer includes at least a negative electrode active material, and may include a conductive agent, a binder, and other materials as necessary.
- aluminum, an aluminum alloy, copper, or a copper alloy can be used.
- a titanium oxide having a lithium ion storage potential of 1.2 V (vs. Li / Li + ) or higher is used.
- active materials include spinel lithium titanate (Li 4 + x Ti 5 O 12 (x is a real number satisfying 0 ⁇ x ⁇ 3), occlusion potential: 1.55 V vs. Li / Li + ) Lithium titanate having a ramsdellite structure (Li 2 + x Ti 3 O 7 (x is a real number satisfying 0 ⁇ x ⁇ 3), occlusion potential: 1.6 V vs. Li / Li + ), monoclinic titanium oxide And lithium hydrogen titanate.
- Examples of monoclinic titanium oxide include monoclinic titanic acid compounds represented by the general formula H 2 Ti n O 2n + 1 (n is an even number of 4 or more.
- H 2 Ti 12 O 25 occlusion Potential: 1.55 V vs. Li / Li +
- monoclinic lithium titanate represented by the general formula Li 2 Ti n O 2n + 1 (n is an even number of 4 or more, such as Li 2 Ti 18 O 37 )
- bronze type titanium oxide (TiO 2 (B) occlusion potential: 1.6 V vs. Li / Li +
- Examples of the lithium hydrogen titanate include those obtained by substituting a part of the lithium element of the lithium titanate with hydrogen.
- H x Li y-x Ti z O 4 (x, y, z is a real number satisfying y ⁇ x> 0, 0.8 ⁇ y ⁇ 2.7, 1.3 ⁇ z ⁇ 2.2)
- H a Li 4 / 3-a Ti 5/3 O 4 where a is a real number satisfying 0 ⁇ a ⁇ 4/3) and the general formula H 2-x Li x Ti Lithium hydrogen titanate represented by n O 2n + 1 (n is an even number of 4 or more and x is a real number satisfying 0 ⁇ x ⁇ 2; for example, H 2 ⁇ x Li x Ti 12 O 25 ).
- some of lithium, titanium, and oxygen may be substituted with other elements, and not only the stoichiometric composition but also non-stoichiometry in which some elements are deficient or excessive. It may be of composition.
- Said titanium oxide may be used independently, but 2 or more types may be mixed and used for it. Further, titanium oxide (for example, TiO 2 ) that becomes a lithium-titanium composite oxide by charging and discharging may be used as the active material. You may mix and use these.
- the upper limit of the lithium ion storage potential of the titanium oxide is not limited to this, but is preferably 2V.
- the negative electrode may contain a known negative electrode active material other than titanium oxide, but the titanium oxide preferably accounts for 50% or more of the negative electrode capacity, and more preferably 80% or more.
- titanium oxide a titanium oxide selected from Li 4 + x Ti 5 O 12 , Li 2 + x Ti 3 O 7 , a titanate compound represented by the general formula H 2 Ti n O 2n + 1 , and bronze-type titanium oxide is used.
- a dinitrile compound is preferable because it easily acts effectively.
- x is a real number satisfying 0 ⁇ x ⁇ 3, and n is an even number of 4 or more.
- Lithium ion storage potential (vs. Li / Li + ) is a coin cell with a counter electrode made of lithium metal foil and charged at a constant current at 25 ° C. and at 0.25 C until the cell voltage reaches 1.0 V. Later, when a potential-capacity curve at the time of charging is drawn in the capacity measurement in which the cell voltage is discharged at a constant current until the cell voltage reaches 3.0 V at 0.25 C, it means the potential corresponding to the middle point of the capacity. .
- the titanium oxide preferably has an average primary particle size of 2 ⁇ m or less.
- the average primary particle size can be obtained as an average obtained by measuring the particle length of 100 primary particles using a scanning electron microscope. Moreover, it is good also as a secondary particle which granulated the primary particle by the well-known method.
- the average secondary particle diameter is preferably 0.1 to 30 ⁇ m. The average secondary particle diameter can be measured by a laser diffraction / scattering method.
- the titanium oxide preferably has a specific surface area of 1 to 20 m 2 / g.
- the specific surface area is 1 m 2 / g or more, an effective area contributing to the electrode reaction can be sufficiently secured, and good charge / discharge characteristics can be obtained. Even if the specific surface area is 20 m 2 / g or more, the effect of the present invention can be obtained, but in the production of the electrode, the dispersibility of the active material in the negative electrode mixture slurry and the coating property of the mixture slurry to the current collector Since there may be a problem in handling such as adhesion between the active material layer and the current collector, the specific surface area is preferably 20 m 2 / g or less.
- a titanium oxide with a large specific surface area such as a specific surface area of 5 m 2 / g or more
- gas generation can be reduced by applying the present invention.
- gas generation accompanying a high temperature cycle can be significantly reduced.
- a titanium oxide having a large specific surface area can be used as the negative electrode active material, a nonaqueous electrolyte secondary battery exhibiting good low-temperature charge / discharge characteristics and large current charge / discharge characteristics can be obtained.
- the specific surface area can be determined by the BET single point method by nitrogen adsorption.
- any material can be used as long as it is a conductive material that does not cause a chemical change in the battery that is used to impart conductivity to the negative electrode.
- a conductive material containing a mixture thereof can be used.
- binder for example, polytetrafluoroethylene (PTFE), polyvinylidene fluoride (PVdF), fluorine-based rubber, styrene-butadiene rubber (SBR), carboxymethylcellulose (CMC), or the like can be used.
- PTFE polytetrafluoroethylene
- PVdF polyvinylidene fluoride
- SBR styrene-butadiene rubber
- CMC carboxymethylcellulose
- Examples of other materials that can be included in the negative electrode active material layer include various known additives.
- the compounding ratio of the negative electrode active material, the conductive agent and the binder is preferably in the range of 70 to 95% by mass of the negative electrode active material, 0 to 25% by mass of the conductive agent, and 2 to 10% by mass of the binder.
- the negative electrode can be produced by preparing a slurry by suspending a negative electrode active material, a conductive agent, and a binder in an appropriate solvent, applying the slurry to one or both sides of a current collector, and drying the slurry. .
- the non-aqueous electrolyte is a liquid non-aqueous electrolyte (non-aqueous electrolyte) prepared by dissolving a lithium salt in a non-aqueous solvent
- the non-aqueous solvent includes a solvent (a) ethylene carbonate, a solvent ( b) cyclic carboxylic acid ester or cyclic carbonate having 4 or more carbon atoms, solvent (c) containing at least three kinds of chain carbonate, lithium salt containing at least lithium hexafluorophosphate and lithium tetrafluoroborate, Solvent (a) A non-aqueous electrolyte solution in which ethylene carbonate is 5 to 20% by volume of the whole non-aqueous solvent and the lithium tetrafluoroborate concentration is 0.05 to 0.5 mol / liter with respect to the non-aqueous electrolyte solution.
- solvent a) ethylene carbonate, a solvent ( b) cyclic carboxylic acid ester or cyclic
- the surface of the negative electrode is It is considered that a film corresponding to SEI is formed.
- This coating has excellent lithium ion conductivity and stability, preventing direct contact between titanium oxide and electrolyte components, and inhibiting electron transfer from titanium oxide to electrolyte components.
- decomposition of the electrolyte component is suppressed and gas generation is suppressed.
- the electrolyte solution of the composition containing at least 5 types of components of this invention has sufficient lithium ion conductivity also in a low temperature range, and the battery using this shows the outstanding low-temperature charge / discharge characteristic.
- this estimation does not limit the present invention.
- cyclic carboxylic acid ester a known cyclic carboxylic acid ester solvent can be used. Examples include ⁇ -butyrolactone (GBL), decanolide, valerolactone, mevalonolactone, and caprolactone.
- GBL ⁇ -butyrolactone
- decanolide decanolide
- valerolactone valerolactone
- mevalonolactone mevalonolactone
- caprolactone caprolactone
- cyclic carbonate having 4 or more carbon atoms those represented by the following formula can be used.
- X represents a hydrocarbon group, and X is particularly preferably an alkyl group having 1 to 3 carbon atoms. Examples of such a substance include propylene carbonate, butylene carbonate, and pentylene carbonate.
- chain carbonate a known chain carbonate solvent can be used, which is represented by C n H 2n + 1 (COO) C m H 2m + 1 (where m and n are each an integer of 1 to 3). Is preferably used. Specific examples include ethyl methyl carbonate and diethyl carbonate.
- ethylene carbonate contained in the non-aqueous electrolyte is 5 to 20% by volume of the whole non-aqueous solvent, and the concentration of lithium tetrafluoroborate is 0.05 to 0.5 mol relative to the non-aqueous electrolyte. / Liter.
- the mass ratio (LiBF 4 / EC) of lithium tetrafluoroborate (LiBF 4 ) and ethylene carbonate (EC) is 0.015 or more and less than 0.72 in the above blending range.
- lithium tetrafluoroborate and ethylene carbonate react in a coordinated manner on the surface of the titanium oxide, so that lithium ion conductivity is high and can exist stably in a wide temperature range. It is presumed that the coating can be formed on the negative electrode surface with an appropriate thickness, and a nonaqueous electrolyte secondary battery having further improved high-temperature cycle characteristics and low-temperature charge / discharge characteristics can be obtained.
- the mass ratio (LiBF 4 / EC) is more preferably 0.03 to 0.15.
- the amount of ethylene carbonate is small, the effect of suppressing gas generation during a high-temperature cycle is not sufficient.
- the amount is too large, gas generation is likely to occur, and it is presumed that a coating film is formed excessively on the negative electrode surface.
- the lithium ion conductivity of the electrolyte solution decreases, the low-temperature charge / discharge characteristics deteriorate.
- the amount of lithium tetrafluoroborate is small, it is presumed that the stability of the coating on the negative electrode surface is lowered, but the effect of suppressing gas generation during a high-temperature cycle is not sufficient.
- the blending amount of ethylene carbonate is preferably 5 to 20% by volume of the whole non-aqueous solvent, and more preferably 5 to 10% by volume.
- the concentration of lithium tetrafluoroborate is preferably 0.05 to 0.5 mol / liter, more preferably 0.05 to 0.3 mol / liter, based on the nonaqueous electrolyte. More preferably, it is 2 mol / liter.
- the respective concentrations in the electrolyte are assumed to gradually decrease after the battery is assembled. Is done.
- the composition of the electrolytic solution used in the present invention only needs to satisfy the composition at least when the battery is assembled. As a result of subsequent use, even if the electrolytic solution does not contain lithium tetrafluoroborate and ethylene carbonate. Good. If the remaining amount of lithium tetrafluoroborate and ethylene carbonate in the electrolytic solution after the manufacture of the battery is large, the above-mentioned problems are likely to occur. Therefore, it is preferable to reduce the remaining amount to such an extent that the respective defects do not appear remarkably.
- b / a is preferably 1 to 9, and more preferably 3 to 7.
- a, b and c satisfy (a + b) ⁇ c.
- c / (a + b) is preferably from 1 to 9, more preferably from 1 to less than 3, and even more preferably from 1.5 to 2.4.
- the molar concentration of lithium hexafluorophosphate in the non-aqueous electrolyte is preferably 0.5 to 1.4 mol / liter. By doing in this way, while the capacity
- the molar concentration of lithium hexafluorophosphate is preferably 0.8 to 1.4.
- the lithium salt in the non-aqueous electrolyte may be only two kinds of lithium hexafluorophosphate and lithium tetrafluoroborate, or may include other lithium salts.
- lithium salts include lithium arsenic hexafluoride (LiAsF 6 ), lithium perchlorate (LiClO 4 ), lithium bistrifluoromethanesulfonylimide (LiN (CF 3 SO 2 ) 2 , LiTSFI) and trifluoro Lithium metasulfonate (LiCF 3 SO 3 ) is included. Of these, one kind or two or more kinds may be further mixed and used.
- the concentration of the lithium salt in the non-aqueous solvent is preferably 0.7 to 1.5 mol / liter.
- the lithium ion conduction resistance of electrolyte solution can be reduced and a charge / discharge characteristic can be improved.
- fusing point and viscosity of electrolyte solution can be suppressed, and it can be made liquid at normal temperature.
- Particularly preferred is 0.85 to 1.45 mol / liter.
- the non-aqueous electrolyte contains, as the solvent (b), a cyclic carbonate or a cyclic carboxylic acid ester having a melting point of ⁇ 30 ° C. or less and a relative dielectric constant of 30 or more, and the solvent (c) has a melting point of ⁇ 40 It is preferable to contain a chain carbonate having a temperature of 0 ° C. or lower. By selecting such a solvent species, an electrolytic solution having excellent lithium ion conductivity can be obtained even at a low temperature.
- the melting point and relative dielectric constant refer to, for example, “Lithium Secondary Battery-Materials and Applications (Masayuki Yoshio, Nikkan Kogyo Shimbun, 1996)”.
- the solvent (c) having a viscosity of 0.5 to 0.8 mPa ⁇ s is more preferable because the mobility of lithium ions is increased.
- the viscosity is measured at 20 ° C. using an E-type rotary viscometer according to JIS K 7117-2.
- solvent (b) examples include propylene carbonate (mp: ⁇ 49 ° C., ⁇ r : 65), butylene carbonate (mp: ⁇ 53 ° C., ⁇ r : 53), pentylene carbonate (mp: ⁇ 45 ° C.).
- the solvent (c) is selected from ethyl methyl carbonate (mp: ⁇ 53 ° C., ⁇ 0 : 0.65 mPa ⁇ s) and diethyl carbonate (mp: ⁇ 43 ° C., ⁇ 0 : 0.75 mPa ⁇ s). At least one selected from the above.
- mp represents a melting point
- ⁇ r represents a relative dielectric constant
- ⁇ 0 represents a viscosity.
- the non-aqueous solvent in the non-aqueous electrolyte may include other than the above (a) to (c).
- non-aqueous organic solvents ester-based, ether-based, ketone-based, alcohol-based, or aprotic solvents can be used. These solvents are preferably 20% by volume or less of the whole non-aqueous solvent.
- ester solvent methyl acetate, ethyl acetate, n-propyl acetate, dimethyl acetate, methyl propionate, ethyl propionate, or the like can be used.
- ether solvent dibutyl ether, tetraglyme, diglyme, dimethoxyethane, 2-methyltetrahydrofuran, tetrahydrofuran and the like can be used.
- ketone solvent cyclohexanone or the like can be used.
- alcohol solvent ethyl alcohol, isopropyl alcohol or the like can be used.
- aprotic solvent examples include R-CN (R is a C2-C20 linear, branched, or cyclic hydrocarbon group, and may include a double-bonded aromatic ring or an ether bond) Nitriles such as dimethylformamide, amides such as dimethylformamide, dioxolanes such as 1,3-dioxolane, sulfolanes, and the like can be used.
- R-CN R is a C2-C20 linear, branched, or cyclic hydrocarbon group, and may include a double-bonded aromatic ring or an ether bond
- Nitriles such as dimethylformamide, amides such as dimethylformamide, dioxolanes such as 1,3-dioxolane, sulfolanes, and the like can be used.
- the electrolyte may further include an additive capable of improving the low temperature characteristics of the lithium battery.
- the additive include dinitrile compounds, carbonate-based materials, ethylene sulfite (ES), and 1,3-propane sultone (Propanesultone, PS).
- any organic dinitrile compound can be used as the dinitrile compound.
- dinitrile compounds represented by the structural formula NC— (CH 2 ) n —CN (where n ⁇ 1, n is an integer) and having a nitrile group bonded to both ends of the chain saturated hydrocarbon compound are This is preferable because it is easily dissolved in the electrolytic solution.
- the carbonate-based material is selected from the group consisting of vinylene carbonate (VC), halogen (eg, —F, —Cl, —Br, —I, etc.), cyano group (CN), and nitro group (—NO 2 ).
- VC vinylene carbonate
- halogen eg, —F, —Cl, —Br, —I, etc.
- CN cyano group
- —NO 2 nitro group
- the additive may be only one kind of substance or two or more kinds of substances.
- the electrolytic solution is selected from the group consisting of succinonitrile (SCN), vinylene carbonate (VC), fluoroethylene carbonate (FEC), ethylene sulfite (ES), and 1,3-propane sultone (PS).
- SCN succinonitrile
- VC vinylene carbonate
- FEC fluoroethylene carbonate
- ES ethylene sulfite
- PS 1,3-propane sultone
- the content thereof is preferably 10 parts by mass or less, more preferably 0.1 to 10 parts by mass per 100 parts by mass of the total amount of the non-aqueous organic solvent and the lithium salt. Within this range, battery characteristics in a high temperature environment can be improved.
- the content of the additive is more preferably 1 to 5 parts by mass.
- Known methods can be used to measure the type and concentration of the solvent and lithium salt in the electrolytic solution.
- analysis of the solvent for example, gas chromatography mass spectrometry can be used, and for the analysis of the solvent and the lithium salt, for example, NMR can be used.
- the positive electrode 2 includes at least a positive electrode current collector 2a and a positive electrode active material layer 2b.
- the positive electrode active material layer is formed on one or both surfaces of the positive electrode current collector, includes at least a positive electrode active material, and may include a conductive agent, a binder, and other materials as necessary.
- the positive electrode current collector for example, aluminum or an aluminum alloy can be used.
- the well-known electrode active material which can function as a positive electrode with respect to the titanium oxide used as a negative electrode active material can be used.
- the lithium ion insertion potential is larger than 1.6V (relative to Li / Li +) or, more preferably equal to 2.0 V (relative to Li / Li +) or more.
- various oxides and sulfides can be used.
- conductive polymer materials such as polyaniline and polypyrrole, disulfide polymer materials, organic materials such as sulfur (S) and carbon fluoride, and inorganic materials can be used.
- an active material having a high lithium ion storage potential is preferably used.
- lithium-manganese composite oxide (Li x Mn 2 O 4 ) having a spinel structure lithium-nickel composite oxide (Li x NiO 2 ), lithium-cobalt composite oxide (Li x CoO 2 ), lithium nickel cobalt complex oxide (Li x Ni 1-y Co y O 2), lithium manganese cobalt composite oxide (Li x Mn y Co 1- y O 2), lithium-nickel-manganese-cobalt composite oxide (Li x Ni y Mn z Co 1-y -z O 2), lithium-manganese-nickel complex oxide having a spinel structure (Li x Mn 2-y Ni y O 4), lithium iron phosphate (Li x FePO 4) such as In particular, lithium-nickel-manganese-cobalt composite oxide and lithium iron phosphate are preferably used. It is.
- acetylene black, carbon black, graphite or the like can be used as the conductive agent.
- binder for example, polytetrafluoroethylene (PTFE), polyvinylidene fluoride (PVdF), fluorine-based rubber, styrene-butadiene rubber (SBR), carboxymethylcellulose (CMC), or the like can be used.
- PTFE polytetrafluoroethylene
- PVdF polyvinylidene fluoride
- SBR styrene-butadiene rubber
- CMC carboxymethylcellulose
- Examples of other materials that can be included in the positive electrode active material layer include various additives, such as dinitrile compounds, fluoroethylene carbonate, vinylene carbonate, 1,3-propane sultone, and ethylene sulfite. .
- the compounding ratio of the positive electrode active material, the conductive agent, and the binder is preferably in the range of 80 to 95% by mass of the positive electrode active material, 3 to 18% by mass of the conductive agent, and 2 to 10% by mass of the binder.
- the positive electrode can be produced by suspending a positive electrode active material, a conductive agent, and a binder in an appropriate solvent to prepare a slurry, applying the slurry to one or both sides of a current collector, and drying the slurry. .
- the separator is disposed between the positive electrode and the negative electrode to prevent the positive electrode and the negative electrode from contacting each other.
- the separator is made of an insulating material.
- the separator has a shape in which the electrolyte can move between the positive electrode and the negative electrode.
- separator examples include a synthetic resin nonwoven fabric, a polyethylene porous film, a polypropylene porous film, and a cellulose separator.
- a laminate film or a metal container can be used.
- a laminate film a multilayer film made of a metal foil covered with a resin film is used.
- the resin forming the resin film polymers such as polypropylene (PP), polyethylene (PE), nylon, and polyethylene terephthalate (PET) can be used.
- the inner surface of the laminate film exterior member is formed of a thermoplastic resin such as PP and PE.
- the thickness of the laminate film is preferably 0.2 mm or less.
- the nonaqueous electrolyte secondary battery of the present invention can be configured such that its charging is regulated by the negative electrode.
- a nonaqueous electrolyte secondary battery that can further suppress gas generation and battery capacity reduction associated with a high-temperature cycle and that is further excellent in low-temperature charge / discharge characteristics is provided. it can.
- the negative electrode capacity is made larger than the positive electrode capacity and regulated as the positive electrode from the viewpoint of preventing metal Li precipitation during charging.
- the positive / negative electrode capacity ratio is set to the negative electrode regulation, particularly the charging side is the negative electrode regulation, the potential of the positive electrode is maintained in a relatively low state during normal use. Film formation on the positive electrode due to the oxidation reaction of electrolyte components such as solvents, lithium salts and additives in the liquid is relatively difficult to occur.
- electrolyte components are appropriately distributed between the positive electrode and the negative electrode containing titanium oxide, and acting on the positive and negative electrodes, the reductive decomposition of the electrolytic solution at the negative electrode is suppressed, and gas generation is also sufficiently suppressed. It is inferred that Further, it is presumed that when the potential of the positive electrode does not become too high, the oxidative decomposition of the electrolytic solution hardly occurs, and the amount of gas generated at the positive electrode is reduced. At the same time, since the potential of the positive electrode does not become too high, deterioration of the crystal structure of the positive electrode active material itself can be suppressed, so that it is possible to further suppress gas generation and battery capacity reduction associated with high-temperature cycles. Is done.
- the positive electrode actual electric capacity is P and the negative electrode actual electric capacity is N
- the values of P and N can be obtained as follows.
- the positive electrode and the lithium metal foil which have been shaped for coin cells, are opposed to each other with a separator interposed therebetween. These members are put in a coin cell, an electrolyte is poured, and the coin cell is sealed in a state where the separator and the electrode are sufficiently impregnated with the electrolyte.
- the electrolyte solution lithium hexafluorophosphate as an electrolyte was added to a mixed solvent in which ethylene carbonate (EC), propylene carbonate (PC) and methyl ethyl carbonate (MEC) were mixed at a volume ratio of 1: 3: 6.
- the manufactured coin cell is charged at a constant current until the cell voltage reaches 4.2 V at 0.25 C in a 25 ° C. environment, and then constant until the cell voltage reaches 3.0 V at 0.25 C. Discharge with current.
- the actual electric capacity P (mAh / cm 2 ) in a 25 ° C. environment per unit area of the positive electrode is calculated.
- the temperature environment for measuring the actual electric capacity is formed using a thermostatic chamber (Yamato Scientific Thermostatic Chamber Model number IN804).
- a coin cell is manufactured in the same manner except that the negative electrode having a shape adapted for coin cell is used.
- the manufactured coin cell was charged at a constant current until the cell voltage reached 1.0 V at 0.25 C in a 25 ° C. environment, and then at a constant current until the cell voltage reached 3.0 V at 0.25 C. Was discharged.
- the actual electric capacity N (mAh / cm 2 ) in a 25 ° C. environment per unit area of the negative electrode is calculated.
- the side where lithium ions are occluded in the active material is referred to as charging, and the side where lithium ions are desorbed is referred to as discharging.
- the method includes the positive electrode, a negative electrode including an active material containing a titanium oxide having a lithium ion storage potential of 1.2 V (vs. Li / Li + ) or higher, a lithium salt, and a nonaqueous solvent for dissolving the lithium salt.
- a non-aqueous electrolyte solution is housed in an exterior member, and includes a step of sealing an opening of the exterior member to obtain a secondary battery, and a step of charging the sealed secondary battery.
- the lithium salt contains at least lithium hexafluorophosphate and lithium tetrafluoroborate, (A) ethylene carbonate is 5 to 20% by volume of the whole non-aqueous solvent, The concentration of lithium tetrafluoroborate is 0.05 to 0.5 mol / liter with respect to the non-aqueous electrolyte. In this way, the nonaqueous electrolyte secondary battery of the present invention can be manufactured. Details will be described together in the section of a method for manufacturing a non-aqueous electrolyte secondary battery including a conditioning process described later.
- the method for manufacturing a non-aqueous electrolyte secondary battery of the present invention preferably includes the following conditioning step.
- the method includes a step of temporarily sealing an opening of an exterior member containing the positive electrode, the negative electrode, and the nonaqueous electrolyte to obtain a temporary sealed secondary battery, and a negative electrode potential of the temporary sealed secondary battery is set to 0.8V.
- a step of fully sealing the exterior member is included.
- gas generation associated with a high-temperature cycle can be further reduced. it can.
- the mechanism of action is not clear and does not limit the present invention, but the present inventor presumes as follows. That is, water, carbon dioxide and the like are adsorbed on the surface of the titanium oxide. These impurities are likely to be released as gas when the negative electrode potential is made lower than the lithium ion storage potential, that is, when the charge is further performed exceeding SOC 100%. Further, when stored at a high temperature, it is considered that lithium tetrafluoroborate and ethylene carbonate are further sufficiently decomposed to form a good film.
- ES ethylene sulfite
- PS 1,3-propane sultone
- these additives are similarly easily decomposed, and a good film is formed on lithium tetrafluoroborate, ethylene carbonate, and titanium oxide in cooperation. Conceivable.
- the negative electrode potential is 1.4 V or less (vs. Li / Li + ) and combining it with high temperature storage, desorption of adsorbed water, carbon dioxide, etc. can be promoted.
- lithium tetrafluoroborate and ethylene carbonate can act on the negative electrode surface, or some kind of film can be formed, which is considered to further enhance the effect of suppressing gas generation.
- such conditioning promotes the consumption of lithium tetrafluoroborate and ethylene carbonate that accompany the formation of the film, so the remaining amount of lithium tetrafluoroborate and ethylene carbonate after battery manufacture is also reduced moderately. can do.
- the electrode group is accommodated in the exterior member.
- the electrode group includes a positive electrode, a negative electrode, and a separator.
- a positive electrode, a separator, a negative electrode, and a separator are sequentially stacked, and the stacked body is wound into a flat shape to form a flat electrode group.
- the electrode group may be formed by laminating one set or a plurality of sets of the positive electrode and the negative electrode via a separator. If necessary, the electrode group may be wound and fixed with an insulating tape. You may add the process of heating and / or vacuum-drying an electrode group and each structural member after formation of an electrode group and / or before formation, and reducing adsorption
- a strip-like positive electrode terminal 7 is electrically connected to the positive electrode 2.
- a strip-shaped negative electrode terminal 8 is electrically connected to the negative electrode 3.
- the positive and negative electrode terminals may be formed integrally with the positive and negative electrode current collectors, respectively. Alternatively, a terminal formed separately from the current collector may be connected to the current collector.
- the positive and negative electrode terminals may be connected to each of the positive and negative electrodes before winding the laminate. Or you may connect, after winding a laminated body.
- the laminate film exterior member is formed by extending or deep drawing the laminate film from the thermoplastic resin film side to form a cup-shaped electrode group housing portion, and then bending it 180 ° with the thermoplastic resin film side inside. And forming a lid.
- a metal container it can be formed, for example, by drawing a metal plate.
- the electrode group is arranged in the electrode group housing part of the exterior member, and the positive and negative electrode terminals are extended to the outside of the container.
- the upper end portion where the positive and negative electrode terminals of the exterior member extend and one of the end portions orthogonal to the upper end portion are heat-sealed to form a sealing portion.
- the exterior member in a state where one side is opened as an opening is formed.
- a non-aqueous electrolyte is injected from the opening, and the electrode group is impregnated with the non-aqueous electrolyte.
- the battery in order to promote the impregnation of the electrolytic solution, the battery may be stored under pressure in the thickness direction, or the electrolytic solution may be injected after the inside of the electrode is decompressed.
- the temporary sealing secondary battery in which the electrode group and the nonaqueous electrolyte impregnated in the electrode group are sealed is obtained by heat-sealing the opening to form a temporary sealing part.
- a sealed secondary battery is obtained by performing main sealing here.
- the second step is performed.
- a current is passed between the positive electrode terminal and the negative electrode terminal of the temporarily sealed secondary battery, and the initial charge is performed so that the negative electrode potential is in the range of a potential higher than 0.8 V and lower than 1.4 V (vs. Li / Li + ). It is more preferable to perform initial charging so that the negative electrode potential is 350 mV or more lower than the lithium ion storage potential of the negative electrode active material.
- the negative electrode potential When the battery is initially charged so that the negative electrode potential is 1.4 V or less (vs. Li / Li + ), it is preferable because gas generation associated with use in a high-temperature environment can be further reduced and battery capacity reduction can be further suppressed. , 1.2 V (vs. Li / Li + ) or less is more preferable. If the battery is initially charged until the negative electrode potential is 0.8 V or less (vs. Li / Li + ), it is estimated that an excessive film is formed on the negative electrode surface. Since it falls, it is not preferable. Further, when aluminum is used for the negative electrode current collector, it is not preferable to lower the negative electrode potential to 0.4 V or less (vs. Li / Li + ) because the current collector aluminum is alloyed with lithium.
- the period from the preparation of the temporarily sealed battery to the initial charging there is no particular limitation on the period from the preparation of the temporarily sealed battery to the initial charging, and it can be arbitrarily set according to the production schedule, etc. For example, it may be 1 hour to 1 month.
- the initial charging and high-temperature storage described below are not limited to the initial charging after preparing the temporarily sealed battery, and charging and discharging and storage are performed once or a plurality of times as long as the gas can be discharged after opening. You may do it after doing.
- Adjustment of the negative electrode potential is, for example, such that, in a cell having the same battery configuration, the negative electrode potential is higher than 0.8V and lower than 1.4V (vs. Li / Li + ) using the reference electrode.
- the amount of electricity charged can be calculated in advance, and the amount of electricity can be adjusted by charging the temporarily sealed battery.
- charging is performed under the same conditions using the reference electrode until the negative electrode potential is higher than 0.8 V and reaches a desired potential in the range of 1.4 V or less (vs. Li / Li + ) This cell voltage can be confirmed, and the initial charge end voltage of the temporarily sealed battery can be adjusted to the value of the confirmed cell voltage.
- Another method may be as follows.
- a coin cell is manufactured by cutting out a positive electrode used for a nonaqueous electrolyte secondary battery as a working electrode, using a metal lithium foil as a counter electrode, and using the same type of electrolyte and separator as the battery.
- the coin cell is charged under the same C rate and temperature conditions as the initial charging of the battery, and a charging curve of vertical axis: potential-horizontal axis: capacity is drawn.
- a potential-capacity curve on the Li storage side including a desired negative electrode potential is drawn using a negative electrode cut out to the same dimensions as in the positive electrode evaluation as a working electrode by a method according to the positive electrode evaluation.
- the obtained potential-capacity curves of the positive electrode and negative electrode are superimposed on one figure, the positive electrode potential corresponding to the capacity when the negative electrode reaches the desired negative electrode potential is read, and the cell voltage is calculated from the positive / negative electrode potential difference.
- the cell voltage is determined as the initial charge end voltage.
- the cell voltage may be 2.7 to 3.3 V when adjusting the negative electrode potential of the temporary sealing battery.
- the voltage is set to 2.9 to 3.3V.
- the cell voltage be 2.1 to 2.7 V when adjusting the negative electrode potential of the temporary sealing battery. More preferably, the voltage is 7V.
- the temperature at which the initial charging is performed can be arbitrarily set, but is preferably about 20 to 45 ° C, and may be performed at room temperature (20 to 30 ° C). It is preferable to perform at room temperature because the equipment can be simplified.
- the initial charge may be performed while pressing the battery body in the thickness direction.
- the method of pressurization for example, a method of performing the initial charge by pressing the battery, or storing the battery in a holder that can be fixed in contact with the front and back of the battery. Is mentioned.
- the charging condition for the step of charging the sealed secondary battery of the present invention (12) is not particularly limited, but the charging condition described in the present invention (13) may be used.
- the temporarily sealed secondary battery initially charged to the negative electrode potential is stored in an atmosphere at a temperature of 50 ° C. or higher and lower than 80 ° C.
- the ambient temperature is less than 50 ° C., it is estimated that it is not industrial because it takes time to release water, carbon dioxide, and the like from the electrode group, and an appropriate film is not formed on the negative electrode surface.
- the high-temperature characteristics of are not sufficient.
- the ambient temperature is 80 ° C. or higher, it is presumed that the reaction of the nonaqueous electrolyte on the surface of the positive electrode or the negative electrode is likely to occur, and an excessive film is formed.
- the decrease in the capacity maintenance rate of the battery also increases.
- a more preferable range of the atmospheric temperature is 50 to 70 ° C.
- the time for storing the temporarily sealed secondary battery in an atmosphere having a temperature of 50 ° C. or higher and lower than 80 ° C. may be a time for sufficiently releasing the gas from the negative electrode. Although not limited thereto, for example, it can be 5 hours to 10 days, preferably 1 day to 8 days.
- This storage time may be adjusted according to the type of positive electrode active material. For example, when a lithium-transition metal composite oxide is used as the positive electrode active material, it can be 5 hours to 8 days, preferably 1 to 7 days. It can be. For example, when lithium iron phosphate is used as the positive electrode active material, it can be 5 hours to 10 days, preferably 5 to 8 days. There is no particular limitation on the time from the initial charging to the start of high-temperature storage, and any time can be set.
- the negative electrode potential increases due to self-discharge.
- the battery is stored at a constant potential by charging the battery substantially continuously during storage, the battery capacity is greatly reduced after storage, and therefore, storage at a constant potential, for example, trickle charge or float charge is not performed. Is preferred.
- charging of about 10% of the self-discharge amount may be intermittently performed during the storage, but it is most preferable to store in an open circuit state.
- the negative electrode potential of the temporarily sealed secondary battery is adjusted to a potential higher than 0.8 V and lower than 1.4 V and stored in an atmosphere of 50 ° C. or higher and lower than 80 ° C.” This does not mean that it is necessary to maintain the negative electrode potential within the above range during the period, and if the negative electrode potential at the end of charging is set as the above potential range, the negative electrode potential rises during the storage period and is outside the above potential range. The thing which becomes is also included. Even in such a case, the effect of the present invention can be obtained.
- the exterior member can be opened by cutting the laminate film at any position of the opening portion that is the inside of the temporary sealing portion and is not heat-sealed. Opening is preferably performed under reduced pressure, and is preferably performed in an inert atmosphere or in dry air.
- the nonaqueous electrolyte secondary battery may be in a reduced pressure atmosphere using a decompression chamber or the like, or gas may be sucked from the opening or hole of the exterior member using a suction nozzle. According to these methods, the gas inside the exterior member can be discharged more reliably.
- the main sealing part is formed by heat-sealing the exterior member inside the cutting part of the opening part, and the electrode group and the nonaqueous electrolyte are sealed again. Further, the opening part is cut outside the main sealing part. Thereby, a nonaqueous electrolyte secondary battery is obtained. At this time, it is preferable to seal under reduced pressure. Or you may affix an adhesive tape etc. on the location which made the hole of the exterior member, and may seal. Even when conditioning is not performed, opening, degassing, and resealing may be performed after the charging step.
- the obtained nonaqueous electrolyte secondary battery may optionally be charged and discharged once or more. Moreover, you may store further at normal temperature or high temperature.
- the conditioning process (second step or second step + third step) may be performed a plurality of times.
- Example 1 Preparation of positive electrode>
- This positive electrode mixture slurry was applied to both sides of a current collector made of an aluminum foil having a thickness of 20 ⁇ m so that the amount of active material per side was 9.5 mg / cm 2 .
- the positive electrode was produced by drying and pressing so that the mixture density was 1.9 g / cm 3 . Thereafter, drying under reduced pressure was performed at 130 ° C. for 8 hours.
- NMP N-methylpyrrolidone
- This slurry was applied to both sides of a current collector made of an aluminum foil having a thickness of 20 ⁇ m so that the amount of active material per side was 8.0 mg / cm 2 . After coating, drying and pressing were performed to produce a negative electrode so that the mixture density was 1.8 to 2.0 g / cm 3 . Thereafter, drying under reduced pressure was performed at 130 ° C. for 8 hours.
- the average secondary particle size of the active material is measured with a laser diffraction method (Laser diffraction / scattering particle size distribution analyzer LA-950, manufactured by Horiba, Ltd.), and the primary particles are measured by electron microscopy (scanning electron microscope S, manufactured by Hitachi High-Technologies Corporation). -4800, average of 100). About the specific surface area, it measured by the BET one-point method by nitrogen adsorption
- Electrode group ⁇ Production of electrode group>
- the sheet-like positive electrode, the separator made of rayon having a thickness of 50 ⁇ m, the sheet-like negative electrode prepared above, and the separator were alternately laminated in this order and fixed with an insulating tape. After fixing, lead tabs made of aluminum foil having a thickness of 20 ⁇ m were welded to the positive electrode and negative electrode current collectors.
- the obtained electrode group was a flat electrode group having a width of 36 mm and a thickness of 3.9 mm.
- the electrode group produced above was housed in an exterior member made of a laminate film with the positive and negative electrode terminals extending from one side, and vacuum dried at 80 ° C. for 8 hours.
- a non-aqueous electrolyte A was injected into the exterior member to impregnate the electrode group.
- the opening part of the laminate film was temporarily sealed by heat sealing and sealed to obtain a temporarily sealed secondary battery.
- ⁇ Second step> As a second step, the temporarily sealed secondary battery is sandwiched between two push plates and fixed with a clip and left to stand for 3 hours, and then a current is passed between the negative electrode terminal and the positive electrode terminal. The battery was charged at room temperature (25 ° C.) until the negative electrode potential reached 1.0 V at 25 C (115 mA). The cell voltage at this time was 2.5V.
- the initially charged temporary sealed secondary battery was stored in an open circuit state for 168 hours in an atmosphere (a constant temperature bath) at a temperature of 55 ° C.
- the temporarily sealed secondary battery after storage was cooled to ambient temperature, a part of the laminate film was cut out and placed in a vacuum chamber, and the gas was discharged. Next, a part of the laminate film was sealed again (main sealing) by heat sealing. In this manner, the nonaqueous electrolyte secondary battery of Example 1 having a width of 60 mm, a thickness of 3.9 mm, and a height of 83 mm, which was prepared and conditioned for the temporarily sealed battery, was produced.
- Example 2 to 27 Comparative Examples 1 to 18
- Example 2 to 27 and Comparative Examples 1 to 18 were prepared in the same manner as in Example 1 except that the nonaqueous electrolytes B to AA and AB to AS shown in Tables 1 and 2 were used as the nonaqueous electrolyte.
- a non-aqueous electrolyte secondary battery was manufactured.
- the concentration of lithium hexafluorophosphate (LiPF 6 ) in the electrolyte solution is x mol / liter
- the concentration of lithium tetrafluoroborate (LiBF 4 ) is y mol / liter
- the concentration of EC in the solvent is a volume%
- the concentration of the solvent (b) in the solvent of propylene carbonate (PC) is in b volume%
- Example 12 b volume% of ⁇ -butyrolactone was used as the solvent (b) instead of propylene carbonate, and c volume% of diethyl carbonate was used as the solvent (c) instead of methyl ethyl carbonate.
- vinylene carbonate (VC) was used in Example 21
- succinonitrile (SCN) was used in Example 22
- ethylene sulfide (ES) was used in Example 23
- 1,3-propane was used in Example 24.
- PS 2% by mass of sultone
- the nonaqueous electrolyte secondary battery is stored in a constant temperature bath at a temperature of 25 ° C. to stabilize the temperature, and then discharged to SOC 0% once (1 C, final voltage 1.0 V). After 30 minutes of rest, 1 C is charged with a constant current to 2.5 V, and after 30 minutes of rest, the capacity when discharged to 1 V at 1 C is defined as the discharge capacity. Under these conditions, the initial capacity was obtained by measuring the discharge capacity after the conditioning process.
- the nonaqueous electrolyte secondary battery was placed in a graduated cylinder containing 500 milliliters of water, and the volume of the battery was measured. The battery volume was measured after the initial capacity measurement and after 500 cycles of the high-temperature cycle test, and the volume change was defined as the gas generation amount. The results are also shown in Tables 3 and 4.
- Comparative Example 14 containing no ethylene carbonate
- Comparative Example 15 containing no lithium tetrafluoroborate
- Comparative Example 17 containing no ethylene carbonate and chain carbonate
- Comparative Example 18 containing ethylene carbonate and cyclic carbonate
- Comparative Example 18 where no gas was generated, gas generation exceeding 3 ml was observed.
- Comparative Example 16 did not function as a battery.
- the gas generation amount was 1.5 ml or less, and the gas generation was greatly reduced.
- all the examples have a discharge capacity retention rate of 90% or more after 500 cycles, and are excellent in high-temperature cycle characteristics together with a reduction in gas generation.
- This positive electrode mixture slurry was applied to both sides of a current collector made of an aluminum foil having a thickness of 20 ⁇ m so that the amount of active material per side was 9.8 mg / cm 2 . After coating, the positive electrode was produced by drying and pressing so that the mixture density was 2.5 g / cm 3 . Thereafter, drying under reduced pressure was performed at 130 ° C. for 8 hours.
- the design capacity was set to 400 mAh in the ⁇ first process>, In the step>, the charging was performed at 0.25 C (100 mA), the charging voltage was 3.1 V (the negative electrode potential was 1.0 V at this time), and the discharging voltage was 1.4 V.
- a nonaqueous electrolyte secondary battery of Example 28 was produced in the same manner.
- Comparative Example 19 A nonaqueous electrolyte secondary battery of Comparative Example 19 was produced in the same manner as in Example 28 except that the electrolytic solution AO was used.
- Comparative Example 20 A nonaqueous electrolyte secondary battery of Comparative Example 20 was produced in the same manner as in Example 28 except that the electrolytic solution AP was used.
- ⁇ Discharge capacity measurement> The nonaqueous electrolyte secondary battery is stored in a constant temperature bath at a temperature of 25 ° C. to stabilize the temperature, and then discharged to SOC 0% once (1 C, final voltage 1.4 V). After 30 minutes of rest, the battery is charged with a constant current to 3.1 V at 1 C, and after 30 minutes of rest, the capacity when discharged to 1.4 V at 1 C is defined as the discharge capacity. What measured the discharge capacity after conditioning on these conditions was made into the initial capacity.
- Example 28 it can be seen that gas generation can be suppressed and the discharge capacity retention rate is high by using electrolytes containing appropriate amounts of ethylene carbonate and lithium tetrafluoroborate, respectively.
- Comparative Example 19 is an electrolyte solution not containing ethylene carbonate
- Comparative Example 20 is an electrolyte solution not containing lithium tetrafluoroborate. In either case, a larger amount of gas was used compared to Example 28. Occurrence was observed. Moreover, the discharge capacity maintenance rate after 500 cycles was less than 90%, and the tendency for the capacity
- lithium iron phosphate (LiFePO 4 ) was used as the positive electrode active material even when a lithium / nickel / manganese / cobalt composite oxide was used as the positive electrode active material. It was confirmed that the same characteristics as in Experiment 1 were exhibited. Similar effects are expected even when other types of positive electrode active materials are used.
- Experiment 3 (Example 29) ⁇ Production of working electrode> After mixing lithium titanate powder having the same spinel structure as used in Experiment 1 and acetylene black as a conductive agent as an active material, an N-methylpyrrolidone (NMP) solution of polyvinylidene fluoride (PVdF) was added. After mixing and adding NMP, the mixture was stirred for 3 minutes at 2000 rpm with an agitator / deaerator (Awatori Nertaro: manufactured by Shinkey Co., Ltd.), and degassed twice at 2200 rpm for 30 seconds.
- NMP N-methylpyrrolidone
- PVdF polyvinylidene fluoride
- the mixture was stirred at 2000 rpm for 5 minutes and defoamed once at 2200 rpm for 30 seconds to prepare a mixture slurry.
- the obtained mixture slurry was applied to one side of a current collector made of an aluminum foil having a thickness of 20 ⁇ m so that the amount of active material per side was 3.0 mg / cm 2 .
- pressing was performed so that the mixture density was 1.8 to 2.0 g / cm 3 , and the electrode material was cut into a circle having a diameter of 12 mm to produce a working electrode. Thereafter, drying under reduced pressure was performed at 130 ° C. for 8 hours.
- This working electrode was incorporated into a sealable coin-type evaluation cell in a glove box having a dew point of ⁇ 70 ° C. or lower.
- the evaluation cell used was made of stainless steel (SUS316) and had an outer diameter of 20 mm and a height of 3.2 mm.
- As the counter electrode (also serving as a reference electrode) a metal lithium foil having a thickness of 0.5 mm formed into a circle having a diameter of 12 mm was used.
- the working electrode prepared above is placed in the lower can of the evaluation cell, and a polypropylene microporous film having a thickness of 20 ⁇ m and the metal lithium foil are placed in this order on the working electrode mixture layer.
- a nonaqueous electrolyte was dropped from above to impregnate the electrode group with the nonaqueous electrolyte. Furthermore, a 0.5 mm thick spacer for adjusting the thickness and a spring (both made of SUS316) were placed thereon, covered with an upper can with a polypropylene gasket, and the outer peripheral edge was caulked and sealed to assemble an evaluation cell. The design capacity was 0.497 mAh.
- the assembled cell was allowed to stand for 3 hours, and then charged at 25 ° C. until a cell voltage reached 1 V by passing a current at 0.25 C (0.124 mA) between the working electrode terminal and the counter electrode terminal. Thereafter, a current was passed at 0.25 C (0.124 mA), and discharging was performed at 25 ° C. until the cell voltage reached 3V. This was performed twice to obtain an evaluation cell.
- the side on which lithium ions are occluded in lithium titanate is called charging.
- Example 30 to 55 Comparative Examples 21 to 38
- Examples 30 to 55 were prepared in the same manner as in Example 29 except that nonaqueous electrolytes B to AA and AB to AS shown in Tables 1 and 2 were used in place of the electrolyte A as the nonaqueous electrolyte. Evaluation cells of Comparative Examples 21 to 38 were produced.
- the low-temperature charge / discharge characteristics are further improved by using (c) the ratio c of the chain carbonate and the electrolytes A to Y in which a and b satisfy (a + b) ⁇ c.
- electrolytic solutions G, H, J, K, R and S having a blending amount a of ethylene carbonate of 5 to 10% by volume and a lithium tetrafluoroborate concentration of 0.05 to 0.3 mol / liter.
- electrolytes S to V to which VC, SCN, ES, or PS are added as electrolyte additives can reduce the amount of gas generated during a higher temperature cycle.
- the nonaqueous electrolyte secondary battery of the present invention can provide a nonaqueous electrolyte secondary battery that can reduce gas generation and battery capacity associated with a high-temperature cycle and is excellent in low-temperature charge / discharge characteristics. Therefore, the nonaqueous electrolyte secondary battery of the present invention can be used for various known applications. Specific examples include notebook computers, pen input computers, mobile computers, electronic book players, mobile phones, mobile faxes, mobile copy, mobile printers, headphone stereos, video movies, LCD TVs, handy cleaners, portable CDs, minidiscs, etc.
- Walkie Talkie Electronic Notebook, Calculator, Memory Card, Portable Tape Recorder, Radio, Backup Power Supply, Motor, Car, Motorcycle, Motorbike, Bicycle, Lighting Equipment, Toy, Game Equipment, Clock, Electric Tool, Strobe, Camera, Load Examples include leveling power sources and natural energy storage power sources.
- Nonaqueous electrolyte secondary battery 2 positive electrode, 2a positive electrode current collector, 2b positive electrode active material layer, 3 negative electrode, 3a negative electrode current collector, 3b negative electrode active material layer, 4 separator, 5 nonaqueous electrolyte solution, 6 exterior member 7 positive terminal, 8 negative terminal.
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Abstract
Description
(a)エチレンカーボネート
(b)環状カルボン酸エステル又は炭素数が4以上の環状カーボネート
(c)鎖状カーボネート
前記リチウム塩が、六フッ化リン酸リチウム及び四フッ化硼酸リチウムを少なくとも含み、
前記エチレンカーボネートが非水溶媒全体の5~20体積%であり、
前記四フッ化硼酸リチウム濃度が非水電解液に対し0.05~0.5モル/リットルである、非水電解質二次電池である。
(a)エチレンカーボネート
(b)環状カルボン酸エステル、又は炭素数が4以上の環状カーボネート
(c)鎖状カーボネート
前記リチウム塩が、六フッ化リン酸リチウム及び四フッ化硼酸リチウムを少なくとも含み、前記エチレンカーボネートが非水溶媒全体の5~20体積%であり、前記四フッ化硼酸リチウム濃度が非水電解液に対し0.05~0.5モル/リットルである、非水電解質二次電池の製造方法である。
前記仮封止二次電池の負極電位を0.8Vより高く1.4V以下の電位(対Li/Li+)に調整し、50℃以上80℃未満の雰囲気中で貯蔵する工程と、
前記仮封止二次電池を開封して内部の気体を排出し、次いで、前記外装部材を本封止する工程と
を含む、非水電解質二次電池の製造方法であって、
前記非水溶媒が、下記(a)、(b)及び(c)の3種を少なくとも含み、
(a)エチレンカーボネート
(b)環状カルボン酸エステル、又は炭素数が4以上の環状カーボネート
(c)鎖状カーボネート
前記リチウム塩が、六フッ化リン酸リチウム及び四フッ化硼酸リチウムを少なくとも含み、
前記エチレンカーボネートが非水溶媒全体の5~20体積%であり、
前記四フッ化硼酸リチウム濃度が非水電解液に対し0.05~0.5モル/リットルである、
非水電解質二次電池の製造方法である。
(a)エチレンカーボネート
(b)環状カルボン酸エステル、又は炭素数が4以上の環状カーボネート
(c)鎖状カーボネート
前記リチウム塩が、六フッ化リン酸リチウム及び四フッ化硼酸リチウムを少なくとも含み、
(a)エチレンカーボネートが非水溶媒全体の5~20体積%であり、
四フッ化硼酸リチウム濃度が非水電解液に対し0.05~0.5モル/リットルである。このようにして本発明の非水電解質二次電池を製造することができる。詳細は後述のコンディショニング工程を含む非水電解質二次電池の製造方法の項で合わせて説明する。
第1の工程において、仮封止二次電池を作製する。まず、外装部材内に電極群を収容する。電極群は正極、負極、及びセパレータから構成される。具体的には、例えば、正極、セパレータ、負極、及びセパレータを順に積層し、この積層体を扁平形状に捲回することにより扁平型の電極群が形成される。別の方法として、例えば、正極と負極とを、セパレータを介して一組又は複数組積層して電極群を形成してもよい。必要に応じて、該電極群を絶縁テープで捲回して固定してもよい。電極群の形成後及び/又は形成前に電極群や各構成部材を加熱及び/又は真空乾燥して吸着水分を低減させる工程を追加してもよい。
次いで、第2の工程を行う。仮封止二次電池の正極端子と負極端子の間に電流を流し、負極電位が0.8Vより高く1.4V以下の電位(対Li/Li+)の範囲になるように初充電する。負極活物質のリチウムイオン吸蔵電位よりも負極電位が350mV以上低くなるように初充電するとより好ましい。
次に、外装部材の一部を切断するか、又は穴を開け、第2の工程において外装部材の中に滞留した気体を外部に排出する。例えば、仮封止部の内側であってヒートシールされていない部分である開封部の何れかの位置においてラミネートフィルムを切断することにより、外装部材を開封することができる。開封は減圧下で行うことが好ましく、また、不活性雰囲気下又は乾燥空気中で行うことが好ましい。
(実施例1)
<正極の作製>
正極活物質としてリン酸鉄リチウム(LiFePO4)粉末、アセチレンブラック、及びポリフッ化ビニリデン(PVdF)のN-メチルピロリドン(NMP)溶液を、質量比がLiFePO4:アセチレンブラック:PVdF=83:10:7となるように混合し、NMPを加えて正極合剤スラリーを調製した。この正極合剤スラリーを厚さ20μmのアルミニウム箔からなる集電体に片面あたりの活物質量が9.5mg/cm2となるように両面に塗布した。塗布後に、乾燥、プレスして合剤密度が1.9g/cm3になるように正極を作製した。その後130℃で8時間減圧乾燥を行った。
負極活物質としてスピネル構造を有するチタン酸リチウム(Li4Ti5O12、リチウム吸蔵電位=1.55V対Li/Li+、比表面積=10.9m2/g、平均二次粒子径=7.4μm、平均一次粒径=0.8μm)の粉末、アセチレンブラック、及びポリフッ化ビニリデン(PVdF)のN-メチルピロリドン(NMP)溶液を、質量比がLi4Ti5O12:アセチレンブラック:PVdF=87.0:4.3:8.7となるように混合し、NMPを加えて負極合剤スラリーを調製した。このスラリーを厚さが20μmのアルミ箔からなる集電体に片面あたりの活物質量が8.0mg/cm2となるように両面に塗布した。塗布後、乾燥、プレスして合剤密度が1.8~2.0g/cm3になるように負極を作製した。その後130℃で8時間減圧乾燥を行った。活物質の平均二次粒子径はレーザー回折法(堀場製作所製 レーザー回折/散乱式粒子径分布測定装置LA‐950)にて測定し、 一次粒子は電子顕微鏡法(日立ハイテクノロジーズ製走査電子顕微鏡 S‐4800、100個の平均)で求めた。比表面積については、比表面積測定装置(モノソーブ:Quantachrome Instruments社製)を用いて、窒素吸着によるBET一点法にて測定した。
シート状正電極と、厚さ50μmのレーヨンからなるセパレータと、上記で作製したシート状負電極と、セパレータとを、この順序で交互に積層して絶縁テープで固定した。固定後に正極、及び負極の集電体に厚さ20μmのアルミニウム箔からなるリードタブを溶接した。得られた電極群は幅が36mmで、厚さが3.9mmの偏平状電極群だった。
溶媒(a)エチレンカーボネート(EC)と溶媒(b)プロピレンカーボネート(PC)と溶媒(c)メチルエチルカーボネート(MEC)の混合溶媒(混合体積比5:35:60)に、リチウム塩として六フッ化リン酸リチウム(LiPF6)を0.5モル/リットル、四フッ化硼酸リチウム(LiBF4)を0.2モル/リットルとなるように溶解した溶液を調製した。これを電解液Aとした。
第1の工程として、ラミネートフィルムからなる外装部材に、上記で作製した電極群を、その正負極端子が一辺から延出した状態で収容し、80℃で8時間真空乾燥した。該外装部材中に非水電解液Aを注入し、電極群に含浸させた。次いで、ラミネートフィルムの開口部をヒートシールにより仮封止して密封し、仮封止二次電池を得た。
第2の工程として、仮封止二次電池を2枚の押し板で挟みクリップで固定することで加圧をして3時間放置後、その負極端子と正極端子の間に電流を流し0.25C(115mA)で負極電位が1.0Vになるまで、常温下(25℃)で充電を行った。このときのセル電圧は2.5Vであった。
非水電解質として、表1、2に記載の非水電解液B~AA、AB~ASを用いた以外は、実施例1と同様な方法にて実施例2~27、比較例1~18の非水電解質二次電池を製造した。表1中、六フッ化リン酸リチウム(LiPF6)の電解液中の濃度をxモル/リットル、四フッ化硼酸リチウム(LiBF4)の濃度をyモル/リットル、溶媒(a)エチレンカーボネート(EC)の溶媒に占める濃度をa体積%、溶媒(b)プロピレンカーボネート(PC)の溶媒に占める濃度をb体積%、溶媒(c)メチルエチルカーボネート(MEC)の溶媒に占める濃度をc体積%で表す。a+b+c=100体積%となるようにした。実施例12では、溶媒(b)としてプロピレンカーボネートに代えてγ-ブチロラクトンをb体積%用い、実施例13では、溶媒(c)としてメチルエチルカーボネートに代えてジエチルカーボネートをc体積%用いた。なお、添加剤として、実施例21にはビニレンカーボネート(VC)、実施例22にはスクシノニトリル(SCN)、実施例23にはエチレンサルファイド(ES)、実施例24には1,3-プロパンスルトン(PS)をそれぞれ電解液に対して2質量%添加した。
上記のようにして作製した実施例1~27及び比較例1~18の非水電解質二次電池について、以下の測定を行った。
非水電解質二次電池を、温度25℃の恒温槽に保存して温度を安定化させた後、一度SOC0%まで放電する(1C、終止電圧1.0V)。30分休止させた後、1Cで2.5Vまで定電流充電し、30分休止させた後、1Cで1.0Vまで放電したときの容量を放電容量とする。この条件で、コンディショニング工程後に放電容量測定を行ったものを初期容量とした。
非水電解質二次電池を、温度55℃の恒温槽に投入し、前記容量測定と同じ充放電条件(充電:1C-終止電圧2.5V、休止:30分、放電:1C-終止電圧1.0V、休止:30分)で500サイクルの充放電を行った。500サイクル後に再度前記放電容量測定を行ってサイクル後容量を求め、放電容量維持率(=サイクル後容量/初期容量)を算出した。結果を表3、4に示す。
非水電解質二次電池を500ミリリットルの水の入ったメスシリンダー内にいれて、電池の体積を測定した。前記初期容量測定後と前記高温サイクル試験500サイクル後に電池体積を測定し、その体積変化量をガス発生量とした。その結果も合わせて表3、4に示す。
(実施例28)
<正極の作製>
正極活物質としてリチウム・ニッケル・マンガン・コバルト複合酸化物(LiNi1/3Mn1/3Co1/3O2)粉末、アセチレンブラック、及びポリフッ化ビニリデン(PVdF)のN-メチルピロリドン(NMP)溶液を、質量比がLiNi1/3Mn1/3Co1/3O2:アセチレンブラック:PVdF=92:4:4となるように混合し、NMPを加えて正極合剤スラリーを調製した。この正極合剤スラリーを厚さ20μmのアルミニウム箔からなる集電体に片面あたりの活物質量が9.8mg/cm2となるように両面に塗布した。塗布後に、乾燥、プレスして合剤密度が2.5g/cm3になるように正極を作製した。その後130℃で8時間減圧乾燥を行った。
電解液AOを使用したこと以外は、実施例28と同様の方法にて比較例19の非水電解質二次電池を作製した。
電解液APを使用したこと以外は、実施例28と同様の方法にて比較例20の非水電解質二次電池を作製した。
上記のようにして作製した実施例28、比較例19,20の非水電解質二次電池について、以下の測定を行った。
非水電解質二次電池を、温度25℃の恒温槽に保存して温度を安定化させた後、一度SOC0%まで放電する(1C、終止電圧1.4V)。30分休止させた後、1Cで3.1Vまで定電流充電し、30分休止させた後、1Cで1.4Vまで放電したときの容量を放電容量とする。この条件でコンディショニング後に放電容量測定を行ったものを初期容量とした。
非水電解質二次電池を、温度55℃の恒温槽に投入し、前記容量測定と同じ充放電条件(充電:1C-終止電圧3.1V、休止:30分、放電:1C-終止電圧1.4V、休止:30分)で500サイクルの充放電を行った。500サイクル後に再度前記放電容量測定を行ってサイクル後容量を求め、放電容量維持率(=サイクル後容量/初期容量)を算出した。結果を表5に示す。
実験1と同様の方法で測定を行った。結果を表5に合わせて示す。
(実施例29)
<作用極の作製>
活物質として、実験1で用いたものと同じスピネル構造を有するチタン酸リチウムの粉末、導電剤としてのアセチレンブラックを混合した後に、ポリフッ化ビニリデン(PVdF)のN-メチルピロリドン(NMP)溶液を加えて混合し、NMPを加えたのち、撹拌・脱泡装置(あわとり練太郎:(株)シンキー社製)で、2000rpmで3分間撹拌し、2200rpmで30秒間脱泡を2回行った。その後、2000rpmで5分間撹拌し、2200rpmで30秒間脱泡を1回行い、合剤スラリーを調製した。質量比はLi4Ti5O12:アセチレンブラック:PVdF=89.3:4.5:6.2である。次に、得られた合剤スラリーを、厚さが20μmのアルミ箔からなる集電体に、片面当りの活物質量が3.0mg/cm2となるように片面に塗布した。乾燥後、合剤密度が1.8~2.0g/cm3になるようにプレスし、電極材料を直径12mmの円形に切り出して作用極を作製した。その後130℃で8時間減圧乾燥を行った。
表1の電解液Aを使用した。
この作用極を露点-70℃以下のグローブボックス中で、密閉可能なコイン型評価用セルに組み込んだ。評価用セルには、材質がステンレス製(SUS316)で外径20mm、高さ3.2mmのものを用いた。対極(兼参照極)には厚み0.5mmの金属リチウム箔を直径12mmの円形に成形したものを用いた。上記で作製した作用極は評価用セルの下部缶に置き、その上に、厚さ20μmのポリプロピレン製の微多孔膜と、前記金属リチウム箔とを、この順序で、作用極の合剤層がセパレータを介して金属リチウム箔に向き合うように積層した後、その上から非水電解液を滴下し、電極群に非水電解質を含浸させた。さらにその上に厚み調整用の0.5mm厚スペーサー及びスプリング(いずれもSUS316製)をのせ、ポリプロピレン製ガスケットのついた上部缶を被せて外周縁部をかしめて密封し、評価セルを組み立てた。設計容量は、0.497mAhだった。
非水電解質として、電解液Aに代えて表1、2に記載の非水電解液B~AA、AB~ASを用いた以外は、実施例29と同様な方法にて実施例30~55、比較例21~38の評価セルを製造した。
上記手順で作製した実施例29~55及び比較例21~38の評価セルに対し、まず、25℃での放電容量を求める。具体的には、電流値0.5C(0.248mA)で1Vまで定電流充電し、30分休止後、0.5C(0.248mA)で3Vまで定電流放電した。この時の放電容量を25℃容量とした。次に、測定温度-40℃での放電容量を求める。評価セルを-40℃の恒温槽に投入し6時間保持したあとに、0.5C(0.248mA)で1Vまで定電流充電し、30分休止後、0.5Cで3Vまで定電流放電した。この時の放電容量を-40℃容量とした。そして、容量維持率=-40℃容量/25℃容量を算出した。結果を表6、7に示す。
Claims (14)
- 正極と、
リチウムイオン吸蔵電位が1.2V(対Li/Li+)以上のチタン酸化物を含有する活物質を含む負極と、
リチウム塩とこれを溶解する非水溶媒を含有してなる非水電解液と、
を備えた非水電解質二次電池であって、
前記非水溶媒が、下記(a)、(b)及び(c)の3種を少なくとも含み、
(a)エチレンカーボネート
(b)環状カルボン酸エステル又は炭素数が4以上の環状カーボネート
(c)鎖状カーボネート
前記リチウム塩が、六フッ化リン酸リチウム及び四フッ化硼酸リチウムを少なくとも含み、
前記エチレンカーボネートが前記非水溶媒全体の5~20体積%であり、
前記四フッ化硼酸リチウムの濃度が前記非水電解液に対し0.05~0.5モル/リットルである、非水電解質二次電池。 - 前記非水溶媒中の前記(a)の割合をa(体積%)、前記(b)の割合をb(体積%)とした際、前記a及び前記bがb≧aを満たす請求項1に記載の非水電解質二次電池。
- 前記非水溶媒中の前記(c)の割合をc(体積%)とした際、前記a、前記b及び前記cが(a+b)≦cを満たす請求項1又は2に記載の非水電解質二次電池。
- 前記非水電解液中の六フッ化リン酸リチウムのモル濃度が、0.5~1.4モル/リットルである請求項1~3のいずれかに記載の非水電解質二次電池。
- 前記(b)は、融点が-30℃以下で比誘電率が30以上の環状カーボネート又は環状カルボン酸エステルを含み、前記(c)は、融点が-40℃以下の鎖状カーボネートを含む請求項1~4のいずれかに記載の非水電解質二次電池。
- 前記(b)は、プロピレンカーボネート、ブチレンカーボネート、ペンチレンカーボネート、γ-ブチロラクトン及びγ-バレロラクトンから選ばれる少なくとも1種を含み、前記(c)は、エチルメチルカーボネート及びジエチルカーボネートから選ばれる少なくとも1種を含む請求項1~5のいずれかに記載の非水電解質二次電池。
- 前記非水電解質二次電池の充電容量は前記負極によって規制される請求項1~6のいずれかに記載の非水電解質二次電池。
- 前記チタン酸化物は、スピネル構造のチタン酸リチウム、ラムスデライト構造のチタン酸リチウム、単斜晶系チタン酸化合物、単斜晶系チタン酸化物及びチタン酸水素リチウムから選ばれる少なくとも1種である請求項1~7のいずれかに記載の非水電解質二次電池。
- 前記チタン酸化物は、Li4+xTi5O12、Li2+xTi3O7、一般式H2TinO2n+1で表されるチタン酸化合物、ブロンズ型酸化チタンから選ばれる少なくとも1種である請求項1~8のいずれかに記載の非水電解質二次電池。(xは0≦x≦3を満たす実数であり、nは4以上の偶数である。)
- 前記非水電解液が、ジニトリル化合物、ビニレンカーボネート、エチレンサルファイト及び1,3-プロパンスルトンから選択される少なくとも1種をさらに含む請求項1~9のいずれかに記載の非水電解質二次電池。
- 前記正極の活物質がリン酸鉄リチウムである請求項1~10のいずれかに記載の非水電解質二次電池。
- 正極と、
リチウムイオン吸蔵電位が1.2V(対Li/Li+)以上のチタン酸化物を含有する活物質を含む負極と、
リチウム塩とこれを溶解する非水溶媒を含有してなる非水電解液と、
を外装部材に収容し、外装部材の開口部を封止して封止二次電池を得る工程と、
前記封止二次電池を充電する工程と、
を含む、非水電解質二次電池の製造方法であって、
前記非水溶媒が、下記(a)、(b)及び(c)の3種を少なくとも含み、
(a)エチレンカーボネート
(b)環状カルボン酸エステル、又は炭素数が4以上の環状カーボネート
(c)鎖状カーボネート
前記リチウム塩が、六フッ化リン酸リチウム及び四フッ化硼酸リチウムを少なくとも含み、
前記エチレンカーボネートが前記非水溶媒全体の5~20体積%であり、
前記四フッ化硼酸リチウム濃度が前記非水電解液に対し0.05~0.5モル/リットルである、
非水電解質二次電池の製造方法。 - 正極と、
リチウムイオン吸蔵電位が1.2V(対Li/Li+)以上のチタン酸化物を含有する活物質を含む負極と、
リチウム塩とこれを溶解する非水溶媒を含有してなる非水電解液と、
を外装部材に収容し、外装部材の開口部を仮封止して仮封止二次電池を得る工程と、
前記仮封止二次電池の負極電位を0.8Vより高く1.4V以下の電位(対Li/Li+)に調整し、50℃以上80℃未満の雰囲気中で貯蔵する工程と、
前記仮封止二次電池を開封して内部の気体を排出し、次いで、前記外装部材を本封止する工程と
を含む、非水電解質二次電池の製造方法であって、
前記非水溶媒が、下記(a)、(b)及び(c)の3種を少なくとも含み、
(a)エチレンカーボネート
(b)環状カルボン酸エステル、又は炭素数が4以上の環状カーボネート
(c)鎖状カーボネート
前記リチウム塩が、六フッ化リン酸リチウム及び四フッ化硼酸リチウムを少なくとも含み、
前記エチレンカーボネートが前記非水溶媒全体の5~20体積%であり、
前記四フッ化硼酸リチウム濃度が前記非水電解液に対し0.05~0.5モル/リットルである、
非水電解質二次電池の製造方法。 - 前記貯蔵を開回路で行う請求項13に記載の非水電解質二次電池の製造方法。
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Cited By (7)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
US20160181603A1 (en) * | 2014-09-12 | 2016-06-23 | Johnson Controls Technology Company | Systems and methods for lithium titanate oxide (lto) anode electrodes for lithium ion battery cells |
WO2016136212A1 (ja) * | 2015-02-27 | 2016-09-01 | 三洋電機株式会社 | 非水電解質二次電池 |
WO2016188884A1 (en) * | 2015-05-27 | 2016-12-01 | Basf Se | Electrochemical cells using combinations of nitrile compounds as additives |
WO2020065831A1 (ja) * | 2018-09-27 | 2020-04-02 | 株式会社村田製作所 | リチウムイオン二次電池 |
WO2021199485A1 (ja) * | 2020-03-31 | 2021-10-07 | 株式会社村田製作所 | 二次電池 |
WO2022149719A1 (ko) * | 2021-01-08 | 2022-07-14 | 삼성전자 주식회사 | 유기전해액 및 이를 포함하는 이차전지 |
JP7504832B2 (ja) | 2021-04-27 | 2024-06-24 | 株式会社東芝 | 二次電池の製造方法、及び二次電池 |
Families Citing this family (6)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
AU2015360385A1 (en) * | 2014-12-12 | 2017-07-06 | Viking Power Systems Pte. Ltd. | Electrochemical cell and method of making the same |
CN115939668A (zh) * | 2016-03-29 | 2023-04-07 | 东丽株式会社 | 二次电池用隔膜和二次电池 |
AU2017308212A1 (en) | 2016-08-12 | 2019-02-21 | Viking Power Systems Pte. Ltd. | Additive containing electrolytes for high energy rechargeable metal anode batteries |
WO2018174269A1 (ja) * | 2017-03-23 | 2018-09-27 | 株式会社 東芝 | 非水電解質電池、電池パック及び電池システム |
US11171362B2 (en) * | 2017-09-12 | 2021-11-09 | Sila Nanotechnologies, Inc. | Electrolyte for a metal-ion battery cell with high-capacity, micron-scale, volume-changing anode particles |
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Citations (6)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
JPH09213329A (ja) * | 1996-01-30 | 1997-08-15 | Fuji Photo Film Co Ltd | 非水二次電池 |
JP2005101003A (ja) * | 2001-01-29 | 2005-04-14 | Matsushita Electric Ind Co Ltd | 非水電解液二次電池 |
WO2008088050A1 (ja) * | 2007-01-19 | 2008-07-24 | Stella Chemifa Corporation | 蓄電素子 |
JP2010153258A (ja) * | 2008-12-25 | 2010-07-08 | Toshiba Corp | 非水電解質電池 |
JP2010530122A (ja) * | 2007-06-13 | 2010-09-02 | アルテアーナノ,インコーポレーテッド | リチウムイオン電池の充電 |
WO2013031253A1 (ja) * | 2011-08-26 | 2013-03-07 | 株式会社 東芝 | 非水電解質二次電池及びその製造方法 |
Family Cites Families (9)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
KR100444410B1 (ko) * | 2001-01-29 | 2004-08-16 | 마쯔시다덴기산교 가부시키가이샤 | 비수전해액이차전지 |
JP2007172986A (ja) * | 2005-12-21 | 2007-07-05 | Toyota Central Res & Dev Lab Inc | 水系リチウム二次電池 |
US8404390B2 (en) * | 2007-04-20 | 2013-03-26 | Ube Industries, Ltd. | Nonaqueous electrolyte solution for lithium secondary battery and lithium secondary battery using the same |
JP5763889B2 (ja) * | 2010-03-16 | 2015-08-12 | パナソニック株式会社 | 非水電解質二次電池の充放電方法 |
CN101867064A (zh) * | 2010-06-11 | 2010-10-20 | 西安瑟福能源科技有限公司 | 兼顾高温性能的低温型锂离子电池电解液及锂离子电池 |
CN101958428B (zh) * | 2010-09-15 | 2013-11-13 | 东莞新能源科技有限公司 | 一种锂离子二次电池 |
CN103069620A (zh) * | 2010-10-01 | 2013-04-24 | 株式会社东芝 | 非水电解质二次电池及其制造方法 |
JP2012256502A (ja) * | 2011-06-08 | 2012-12-27 | Sony Corp | 非水電解質および非水電解質電池、ならびに非水電解質電池を用いた電池パック、電子機器、電動車両、蓄電装置および電力システム |
CN103208654A (zh) * | 2013-03-28 | 2013-07-17 | 东莞新能源科技有限公司 | 软包装锂离子二次电池用电解液及包含该电解液的电池 |
-
2014
- 2014-05-21 WO PCT/JP2014/063485 patent/WO2015033620A1/ja active Application Filing
- 2014-05-21 TW TW103117739A patent/TWI616012B/zh not_active IP Right Cessation
- 2014-05-21 CN CN201480047147.4A patent/CN105493332A/zh active Pending
- 2014-05-21 JP JP2015535342A patent/JP6232070B2/ja active Active
- 2014-05-21 US US14/912,806 patent/US20160204432A1/en not_active Abandoned
- 2014-05-21 KR KR1020167005807A patent/KR20160054472A/ko not_active Application Discontinuation
Patent Citations (6)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
JPH09213329A (ja) * | 1996-01-30 | 1997-08-15 | Fuji Photo Film Co Ltd | 非水二次電池 |
JP2005101003A (ja) * | 2001-01-29 | 2005-04-14 | Matsushita Electric Ind Co Ltd | 非水電解液二次電池 |
WO2008088050A1 (ja) * | 2007-01-19 | 2008-07-24 | Stella Chemifa Corporation | 蓄電素子 |
JP2010530122A (ja) * | 2007-06-13 | 2010-09-02 | アルテアーナノ,インコーポレーテッド | リチウムイオン電池の充電 |
JP2010153258A (ja) * | 2008-12-25 | 2010-07-08 | Toshiba Corp | 非水電解質電池 |
WO2013031253A1 (ja) * | 2011-08-26 | 2013-03-07 | 株式会社 東芝 | 非水電解質二次電池及びその製造方法 |
Cited By (10)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
US20160181603A1 (en) * | 2014-09-12 | 2016-06-23 | Johnson Controls Technology Company | Systems and methods for lithium titanate oxide (lto) anode electrodes for lithium ion battery cells |
WO2016136212A1 (ja) * | 2015-02-27 | 2016-09-01 | 三洋電機株式会社 | 非水電解質二次電池 |
WO2016188884A1 (en) * | 2015-05-27 | 2016-12-01 | Basf Se | Electrochemical cells using combinations of nitrile compounds as additives |
WO2020065831A1 (ja) * | 2018-09-27 | 2020-04-02 | 株式会社村田製作所 | リチウムイオン二次電池 |
JPWO2020065831A1 (ja) * | 2018-09-27 | 2021-08-30 | 株式会社村田製作所 | リチウムイオン二次電池 |
WO2021199485A1 (ja) * | 2020-03-31 | 2021-10-07 | 株式会社村田製作所 | 二次電池 |
DE112020006663T5 (de) | 2020-03-31 | 2022-11-24 | Murata Manufacturing Co., Ltd. | Sekundärbatterie |
JP7380845B2 (ja) | 2020-03-31 | 2023-11-15 | 株式会社村田製作所 | 二次電池 |
WO2022149719A1 (ko) * | 2021-01-08 | 2022-07-14 | 삼성전자 주식회사 | 유기전해액 및 이를 포함하는 이차전지 |
JP7504832B2 (ja) | 2021-04-27 | 2024-06-24 | 株式会社東芝 | 二次電池の製造方法、及び二次電池 |
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