WO2021189425A1 - 二次电池和包含二次电池的装置 - Google Patents
二次电池和包含二次电池的装置 Download PDFInfo
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- WO2021189425A1 WO2021189425A1 PCT/CN2020/081691 CN2020081691W WO2021189425A1 WO 2021189425 A1 WO2021189425 A1 WO 2021189425A1 CN 2020081691 W CN2020081691 W CN 2020081691W WO 2021189425 A1 WO2021189425 A1 WO 2021189425A1
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- H01M4/13—Electrodes for accumulators with non-aqueous electrolyte, e.g. for lithium-accumulators; Processes of manufacture thereof
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- 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
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- H01M4/583—Carbonaceous material, e.g. graphite-intercalation compounds or CFx
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- H01M2004/027—Negative electrodes
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- H01M4/13—Electrodes for accumulators with non-aqueous electrolyte, e.g. for lithium-accumulators; Processes of manufacture thereof
- H01M4/136—Electrodes based on inorganic compounds other than oxides or hydroxides, e.g. sulfides, selenides, tellurides, halogenides or LiCoFy
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- 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
- H01M4/50—Selection of substances as active materials, active masses, active liquids of inorganic oxides or hydroxides of manganese
- H01M4/505—Selection of substances as active materials, active masses, active liquids of inorganic oxides or hydroxides of manganese of mixed oxides or hydroxides containing manganese for inserting or intercalating light metals, e.g. LiMn2O4 or LiMn2OxFy
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- 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
- H01M4/52—Selection of substances as active materials, active masses, active liquids of inorganic oxides or hydroxides of nickel, cobalt or iron
- H01M4/525—Selection of substances as active materials, active masses, active liquids of inorganic oxides or hydroxides of nickel, cobalt or iron of mixed oxides or hydroxides containing iron, cobalt or nickel for inserting or intercalating light metals, e.g. LiNiO2, LiCoO2 or LiCoOxFy
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- 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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- 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
- This application belongs to the technical field of energy storage devices, and specifically relates to a secondary battery and a device containing the secondary battery.
- Secondary batteries are widely used in various electronic products and electric devices due to their advantages of high energy density, high working voltage, no pollution and no memory effect. For example, with increasing attention to environmental protection issues and the increasing popularity of new energy vehicles, the demand for power-type secondary batteries has shown explosive growth.
- the first aspect of the present application provides a secondary battery, which includes a positive pole piece and a negative pole piece.
- a positive electrode membrane, the negative electrode piece comprising a negative electrode current collector and a negative electrode membrane provided on at least one surface of the negative electrode current collector and comprising a negative electrode active material, wherein,
- the positive electrode active material includes one or more of layered lithium transition metal oxides and modified compounds thereof;
- the negative active material includes artificial graphite and natural graphite, and the negative pole piece satisfies: 0.02 ⁇ I 3R(012) /I 2H(100) ⁇ 0.18, preferably 0.04 ⁇ I 3R(012) /I 2H( 100) ⁇ 0.12;
- the I 3R (012) is the peak intensity of the X-ray diffraction peak of the 3R phase 012 crystal plane of the negative electrode active material in the negative pole piece
- the I 2H (100) is the peak intensity of the X-ray diffraction peak in the negative pole piece.
- the peak intensity of the X-ray diffraction peak of the 2H phase 100 crystal plane of the negative electrode active material.
- a second aspect of the present application provides a secondary battery, which includes a positive pole piece and a negative pole piece.
- a positive electrode membrane, the negative electrode piece comprising a negative electrode current collector and a negative electrode membrane provided on at least one surface of the negative electrode current collector and comprising a negative electrode active material, wherein,
- the positive electrode active material includes one or more of olivine structured lithium-containing phosphate and its modified compounds
- the negative active material includes artificial graphite and natural graphite, and the negative pole piece satisfies: 0.04 ⁇ I 3R(012) /I 2H(100) ⁇ 0.22, preferably 0.06 ⁇ I 3R(012) /I 2H( 100) ⁇ 0.18;
- the I 3R (012) is the peak intensity of the X-ray diffraction peak of the 3R phase 012 crystal plane of the negative electrode active material in the negative pole piece
- the I 2H (100) is the peak intensity of the X-ray diffraction peak in the negative pole piece.
- the peak intensity of the X-ray diffraction peak of the 2H phase 100 crystal plane of the negative electrode active material.
- a third aspect of the present application provides a device including the secondary battery according to the first aspect and/or the second aspect of the present application.
- the negative electrode active material of the negative electrode piece when a specific type of positive electrode active material is selected for the positive electrode piece, includes both artificial graphite and natural graphite, and the I 3R(012) /I of the negative electrode piece
- 2H(100) is controlled in a specific range, it can improve the active ion transport performance of the negative electrode, so that the secondary battery can obtain better charging performance under the premise of higher energy density, and even better Low temperature charging performance.
- the negative pole piece also has higher surface stability, so that the secondary battery has a higher high temperature cycle life.
- the device of the present application includes the secondary battery provided by the present application, and thus has at least the same advantages as the secondary battery.
- FIG. 1 is a schematic diagram of an embodiment of a secondary battery.
- Fig. 2 is an exploded view of Fig. 1.
- Fig. 3 is a schematic diagram of an embodiment of a battery module.
- Fig. 4 is a schematic diagram of an embodiment of a battery pack.
- Fig. 5 is an exploded view of Fig. 4.
- Fig. 6 is a schematic diagram of an embodiment of a device in which a secondary battery is used as a power source.
- any lower limit can be combined with any upper limit to form an unspecified range; and any lower limit can be combined with other lower limits to form an unspecified range, and any upper limit can be combined with any other upper limit to form an unspecified range.
- every point or single value between the end points of the range is included in the range. Therefore, each point or single numerical value can be used as its own lower limit or upper limit in combination with any other point or single numerical value or in combination with other lower or upper limits to form an unspecified range.
- the first aspect of the application provides a secondary battery.
- the secondary battery includes a positive pole piece, a negative pole piece, and an electrolyte.
- active ions are inserted and extracted back and forth between the positive pole piece and the negative pole piece.
- the electrolyte conducts ions between the positive pole piece and the negative pole piece.
- the positive pole piece may include a positive electrode current collector and a positive electrode membrane provided on at least one surface of the positive electrode current collector.
- the positive electrode current collector has two opposite surfaces in its thickness direction, and the positive electrode film is laminated on either or both of the two surfaces of the positive electrode current collector.
- the positive electrode current collector can be made of materials with good electrical conductivity and mechanical strength to play the role of conduction and current collection.
- aluminum foil may be used as the anode current collector.
- the positive electrode membrane includes a positive electrode active material.
- a positive electrode active material for a secondary battery known in the art can be used.
- the positive electrode active material may include one or more of layered lithium transition metal oxides and modified compounds thereof, olivine-structured lithium-containing phosphates and modified compounds thereof, and the like.
- the "modification” in the “modified compound” may be doping modification and/or surface coating modification of the material.
- the positive active material includes one or more of layered lithium transition metal oxides and modified compounds thereof.
- the layered lithium transition metal oxide may include, but is not limited to, lithium cobalt oxide, lithium nickel oxide, lithium manganese oxide, lithium nickel cobalt oxide, lithium manganese cobalt oxide, lithium nickel manganese oxide, One or more of lithium nickel cobalt manganese oxide, lithium nickel cobalt aluminum oxide and modified compounds thereof.
- the layered lithium transition metal oxide includes one or more of lithium nickel cobalt manganese oxide, lithium nickel cobalt aluminum oxide and modified compounds thereof.
- the positive electrode active material comprising Li a Ni b Co c M d M 'Li a Ni b Co c M d e O f A g and at least a portion of the surface having a coating layer M' e O f A
- M is selected from Mn and Al
- M' is selected from one or more of Zr, Al, Zn, Cu, Cr, Mg, Fe, V, Ti and B
- A is selected from N, F, S and Cl One or more of them.
- M is selected from Mn, and M'is selected from one or more of Zr, Al, Zn, Cu, Cr, Mg, Fe, V, Ti and B, preferably including Zr, Al, Zn and One or more of B.
- M is selected from Al, and M'is selected from one or more of Zr, Zn, Cu, Cr, Mg, Fe, V, Ti and B, preferably including one or more of Zr, Zn and B .
- the positive electrode active material includes a high nickel ternary positive electrode active material, which can have a higher gram capacity, thereby increasing the energy density of the battery.
- a coating layer may be provided on 80% to 100% of the surface of the Li a Ni b Co c M d M'e O f A g material. Further, a coating layer may be provided on 90% to 100% of the surface of the Li a Ni b Co c M d M'e O f A g material.
- the positive electrode active material includes lithium-containing phosphate with an olivine structure and modified compounds thereof.
- the lithium-containing phosphate with an olivine structure may include, but is not limited to, lithium iron phosphate, composite material of lithium iron phosphate and carbon, lithium manganese phosphate, composite material of lithium manganese phosphate and carbon and its modified compounds.
- the lithium-containing phosphate with an olivine structure includes one or more of lithium iron phosphate, a composite material of lithium iron phosphate and carbon, and modified compounds thereof.
- the composite material of lithium iron phosphate and carbon can be one or more of a coated composite material and an embedded composite material.
- the coated composite material has a carbon coating layer on at least a part of the surface of the lithium iron phosphate particles.
- the carbon coating layer covers 80%-100% (such as 90%-100%) of the surface of the lithium iron phosphate particles.
- the carbon coating layer may include one or more of graphite, hard carbon, soft carbon, carbon black, coke, and the like.
- the embedded composite material is lithium iron carbonate dispersed in a carbon carrier.
- the carbon support may include one or more of graphite, hard carbon, soft carbon, carbon black, coke, and the like.
- the composite material of lithium manganese phosphate and carbon may be one or more of a coated composite material and an embedded composite material.
- the coated composite material has a carbon coating layer on at least a part of the surface of lithium manganese phosphate particles.
- the carbon coating layer covers 80%-100% (such as 90%-100%) of the surface of the lithium manganese phosphate particles.
- the carbon coating layer may include one or more of graphite, hard carbon, soft carbon, carbon black, coke, and the like.
- the embedded composite material is manganese lithium carbonate dispersed in a carbon carrier.
- the carbon support may include one or more of graphite, hard carbon, soft carbon, carbon black, coke, and the like.
- the positive electrode membrane may also optionally include a binder.
- a binder There is no specific restriction on the type of binder, and those skilled in the art can make a selection according to actual needs.
- the binder used for the positive electrode membrane may include one or more of polyvinylidene fluoride (PVDF) and polytetrafluoroethylene (PTFE).
- a conductive agent is optionally included in the positive electrode film.
- the type of conductive agent is not specifically limited, and those skilled in the art can make a selection according to actual needs.
- the conductive agent used for the positive electrode film may include one or more of graphite, superconducting carbon, acetylene black, carbon black, Ketjen black, carbon dots, carbon nanotubes, graphene, and carbon nanofibers.
- the negative electrode piece includes a negative electrode current collector and a negative electrode membrane provided on at least one surface of the negative electrode current collector.
- the negative electrode current collector has two opposite surfaces in its thickness direction, and the negative electrode film is laminated on either or both of the two surfaces of the negative electrode current collector.
- the negative electrode current collector can be made of materials with good electrical conductivity and mechanical strength to play the role of conduction and current collection.
- copper foil may be used as the negative electrode current collector.
- a negative electrode comprising a negative electrode active material film, the negative electrode active material comprising natural graphite and artificial graphite, it has surprisingly been found that, if I 3R while the negative pole piece (012) / I 2H (100 ) is controlled within a specific range, can
- the negative pole piece has a higher energy density and at the same time improves the active ion transport performance of the negative pole piece, so that the secondary battery adopts it under the premise of a higher energy density, and improves the charging performance, even improving the low temperature charging performance .
- the negative pole piece also has higher surface stability, so that the secondary battery also has a higher high-temperature cycle life.
- I 3R (012) is the peak intensity of the X-ray diffraction peak of the 3R phase 012 crystal plane of the negative electrode active material in the negative electrode piece
- I 2H (100) is the peak intensity of the negative electrode active material in the negative electrode piece.
- I 3R (012) and I 2H (100) can be obtained by X-ray diffraction pattern testing.
- the inventor has conducted in-depth research and found that when the positive electrode active material of the positive pole piece includes layered lithium transition metal oxide and its modified compound, the negative pole piece satisfies: 0.02 ⁇ I 3R(012) /I 2H(100) ⁇ 0.18.
- the positive electrode active material includes one or more of the layered lithium transition metal oxide and its modified compounds, which can make the positive electrode pole piece have a higher areal density and compaction density, so that the battery has a higher energy density.
- the areal density and compaction density of the negative pole piece are correspondingly higher.
- the negative electrode active material of the negative electrode piece includes both artificial graphite and natural graphite, and the negative electrode piece satisfies 0.02 ⁇ I 3R(012) /I 2H(100) ⁇ 0.18, which can make the negative electrode piece have more active ions
- the kinetic performance of the negative pole piece for inserting and extracting active ions is significantly improved, and it can have a higher active ion diffusion rate even in a low temperature environment, achieving rapid reception of active ions from the positive electrode, and improving the low temperature of the secondary battery Charging performance;
- the negative pole piece can also maintain high surface stability, effectively reduce side reactions of the electrolyte, and also reduce the side reaction of the negative electrode active material and the transition metal eluted from the positive electrode, so that the battery has a longer The cycle life, even has a long high temperature cycle life.
- the secondary battery may have good rapid charging capability, and the probability of lithium precipitation from the negative electrode during high-rate charging is significantly reduced.
- the I 3R(012) /I 2H(100) of the negative pole piece can be 0.05, 0.06, 0.08, 0.10, 0.11, or 0.12.
- the I 3R(012) /I 2H(100) of the negative pole piece is in the proper range, which can make the secondary battery better balance low-temperature charging performance and high-temperature cycle performance.
- the positive electrode active material includes one or more of lithium nickel cobalt manganese oxide, lithium nickel cobalt aluminum oxide and modified compounds thereof. This can better exert the above effects.
- the negative pole piece further satisfies: 0.02 ⁇ I 3R(101) /I 2H(101) ⁇ 0.18.
- the positive electrode active material includes one or more of the layered lithium transition metal oxide and its modified compounds
- the negative electrode active material includes both artificial graphite and natural graphite
- the negative electrode piece satisfies 0.02 ⁇ I 3R( 012) /I 2H(100) ⁇ 0.18, the I 3R(101) /I 2H(101) of the negative pole piece is in an appropriate range, which can further balance the ion transport performance and surface stability of the negative pole piece, thereby further improving Low temperature charging performance and high temperature cycle performance.
- 0.04 ⁇ I 3R(101) /I 2H(101) ⁇ 0.15. More preferably, 0.04 ⁇ I 3R(101) /I 2H(101) ⁇ 0.12.
- the I 3R(101) /I 2H(101) of the negative pole piece can be 0.05, 0.06, 0.08, 0.10, 0.11, or 0.12.
- I 3R (101) is the peak intensity of the X-ray diffraction peak of the 101 crystal plane of the 3R phase of the negative electrode active material in the negative electrode piece
- I 2H (101) is the peak intensity of the negative electrode active material in the negative electrode piece.
- I 3R (101) and I 2H (101) can be obtained by X-ray diffraction pattern testing.
- the positive electrode active material includes one or more of the layered lithium transition metal oxide and its modified compounds
- the negative electrode active material includes both artificial graphite and natural graphite
- the negative electrode piece satisfies 0.02 ⁇ I When 3R(012) /I 2H(100) ⁇ 0.18, if the negative electrode active material still satisfies one or more of the following conditions, the performance of the battery can be further improved.
- the positive electrode active material includes one or more of lithium nickel cobalt manganese oxide, lithium nickel cobalt aluminum oxide and modified compounds thereof.
- the mass proportion of natural graphite in the negative electrode active material is ⁇ 50%, for example, 10%-50%.
- the negative electrode active material contains an appropriate amount of natural graphite, which can increase the peak intensity of the X-ray diffraction peaks of the 3R phase crystal plane (such as the 012 crystal plane and/or the 101 crystal plane) of the negative electrode active material in the negative pole piece, and increase the negative pole piece’s Active ion transmission sites can also ensure that the negative pole piece has low side reaction activity, thereby further improving the low-temperature charging performance and high-temperature cycle life of the battery.
- the negative electrode active material contains an appropriate amount of natural graphite, which can also enable the negative electrode active material to have a higher gram capacity, and can increase the compaction density of the negative electrode membrane, thereby increasing the energy density of the battery.
- the mass ratio of natural graphite in the negative electrode active material is 10%-30%. More preferably, it is 15% to 25%.
- the mass ratio of natural graphite in the negative active material is 16%, 18%, 20%, 22%, 24%, 26% or 28%.
- the average particle size D V 50 of the negative active material is 11 ⁇ m to 15 ⁇ m, more preferably 12 ⁇ m to 14 ⁇ m.
- the D v 50 of the negative electrode active material is in an appropriate range, which can ensure its high gram capacity while reducing the side reactions that occur on the surface of the negative electrode piece, and shorten the migration path of active ions and electrons in the particles to make it active Ions and electrons have a higher migration rate in the negative pole piece, so that the battery has a higher energy density, while improving the high-temperature cycle life and low-temperature charging performance.
- the volume average particle size D v 50 of the artificial graphite is preferably 12 ⁇ m to 16 ⁇ m, more preferably 13 ⁇ m to 15 ⁇ m.
- the volume average particle diameter D v 50 of natural graphite is preferably 10 ⁇ m to 14 ⁇ m, and more preferably 11 ⁇ m to 13 ⁇ m.
- the D v 50 of natural graphite in an appropriate range can also increase the peak intensity of the X-ray diffraction peaks of the 3R phase crystal planes (such as the 012 crystal plane and/or the 101 crystal plane) of the negative electrode active material in the negative electrode, and increase the negative electrode
- the active ion transmission sites of the sheet can also ensure that the negative electrode sheet has low side reaction activity, thereby helping to improve the low-temperature charging performance and high-temperature cycle life of the battery.
- the negative electrode active material a tap density ⁇ 1.1g / cm 3, preferably from 1.1g / cm 3 ⁇ 1.15g / cm 3.
- the tap density of the negative electrode active material is within an appropriate range, and the negative electrode diaphragm using it can obtain a higher compaction density, and can have a higher active ion and electron transport performance, thereby improving the energy density and low-temperature charging performance of the battery .
- the negative pole piece can also have higher cohesion and adhesion, which can reduce the volume expansion of the battery during high-temperature cycling, thereby also improving the high-temperature cycle life of the battery.
- the tap density of the artificial graphite is 1.0 g/cm 3 to 1.3 g/cm 3 , It is preferably 1.1 g/cm 3 to 1.2 g/cm 3 ; the tap density of natural graphite is 0.90 g/cm 3 to 1.2 g/cm 3 , preferably 1.0 g/cm 3 to 1.15 g/cm 3 .
- the graphitization degree of the negative electrode active material is 92%-96%, preferably 93%-95%.
- the graphitization degree of the negative electrode active material is in an appropriate range, which can make it have a higher gram capacity and a larger interlayer spacing, which reduces the diffusion resistance of active ions in the interior.
- the contact area between the negative electrode active material particles and between the negative electrode active material and the negative electrode current collector is relatively large, which can further improve the transmission of active ions and electrons inside the negative electrode piece.
- the negative pole piece can also have higher cohesion and adhesion, and can further improve the high temperature cycle performance of the battery using it.
- the graphitization degree of the artificial graphite can be 90%-95%, more preferably 91% ⁇ 93%; the degree of graphitization of natural graphite can be 95% to 98%, more preferably 95% to 97%.
- the positive electrode active material includes one or more of the layered lithium transition metal oxide and its modified compounds
- the negative electrode active material includes both artificial graphite and natural graphite
- the negative electrode piece satisfies 0.02 ⁇ I 3R When (012) /I 2H(100) ⁇ 0.18, if the negative electrode membrane still meets one or more of the following conditions, the battery performance can be further improved.
- the positive electrode active material includes one or more of lithium nickel cobalt manganese oxide, lithium nickel cobalt aluminum oxide and modified compounds thereof.
- the areal density of the negative electrode film is 10 mg/cm 2 -13 mg/cm 2 , more preferably 10.5 mg/cm 2 -11.5 mg/cm 2 .
- the battery can have a higher energy density.
- the battery also has better active ion and electron transmission performance, thereby further improving the low-temperature charging performance of the battery.
- the negative pole piece meets the above design, the negative pole polarization and side reactions can be reduced, thereby further improving the high temperature cycle performance of the battery.
- the compacted density of the negative electrode film is 1.6g/cm 3 ⁇ 1.8g/cm 3 , more preferably 1.65g/cm 3 ⁇ 1.75g/cm 3 , especially preferably 1.65g/cm 3 ⁇ 1.7g/cm 3 .
- the compaction density of the negative electrode film is within the given range, it can ensure that the battery has a higher energy density.
- the close contact between the negative electrode active material particles can effectively reduce the resistance of the negative electrode membrane, thereby further improving the low-temperature charging performance of the battery.
- the proper compaction density can also protect the integrity of the negative electrode active material particle structure, which is beneficial to improve the cohesion and adhesion of the negative electrode pieces, reduce the expansion and side reactions during the battery cycle, and further improve the cycle life of the battery And safety performance.
- the inventor also found that when the positive electrode active material of the positive pole piece includes one or more of the olivine structured lithium-containing phosphate and its modified compounds, the negative pole piece satisfies: 0.04 ⁇ I 3R(012) /I 2H(100) ⁇ 0.22.
- the negative electrode active material of the negative electrode piece includes both artificial graphite and natural graphite, and the negative electrode piece satisfies 0.04 ⁇ I 3R When (012) /I 2H(100) ⁇ 0.22, it can make the negative pole piece have more active ion transmission sites, and the kinetic performance of the negative pole piece to insert and remove active ions is significantly improved, and it can also be used in low temperature environments. It has a high diffusion rate of active ions, which can quickly receive active ions from the positive electrode and improve the low-temperature charging performance of the secondary battery; and the negative electrode can also maintain high surface stability at the same time, reducing the electrolyte on its surface. Side reactions, so that the battery also has a longer high temperature cycle life. Further, the secondary battery can have good fast charging performance, and the probability of lithium precipitation from the negative electrode during high-rate charging is significantly reduced.
- the I 3R(012) /I 2H(100) of the negative pole piece can be 0.07, 0.08, 0.09, 0.10, 0.11, 0.12, 0.13, 0.14, 0.15, or 0.16.
- the I 3R(012) /I 2H(100) of the negative pole piece is in the proper range, which can make the secondary battery better balance low-temperature charging performance and high-temperature cycle performance.
- the positive electrode active material includes one or more of lithium iron phosphate, a composite material of lithium iron phosphate and carbon, and modified compounds thereof. This can better exert the above effects.
- the negative pole piece further satisfies: 0.04 ⁇ I 3R(101) /I 2H(101) ⁇ 0.22.
- the positive electrode active material includes one or more of olivine-structured lithium-containing phosphate and its modified compounds
- the negative electrode active material includes both artificial graphite and natural graphite
- the negative electrode piece satisfies 0.04 ⁇ I 3R (012) /I 2H(100) ⁇ 0.22
- the I 3R(101) /I 2H(101) of the negative pole piece is in the proper range, which can further balance the ion transport performance and surface stability of the negative pole piece, thereby further Improve low-temperature charging performance and high-temperature cycle performance.
- the I 3R(101) /I 2H(101) of the negative pole piece can be 0.07, 0.08, 0.09, 0.10, 0.11, 0.12, 0.13, 0.14, 0.15, or 0.16.
- the positive electrode active material includes one or more of olivine-structured lithium-containing phosphate and its modified compounds
- the negative electrode active material includes both artificial graphite and natural graphite, and the negative electrode piece satisfies 0.04 ⁇ When I 3R(012) /I 2H(100) ⁇ 0.22, if the negative electrode active material still satisfies one or more of the following conditions, the performance of the battery can be further improved.
- the positive electrode active material includes one or more of lithium iron phosphate, composite material of lithium iron phosphate and carbon and modified compounds thereof,
- the mass ratio of natural graphite in the negative electrode active material is ⁇ 20%, for example, 20%-50%.
- the negative electrode active material contains an appropriate amount of natural graphite, which can increase the peak intensity of the X-ray diffraction peaks of the 3R phase crystal plane (such as the 012 crystal plane and/or the 101 crystal plane) of the negative electrode active material in the negative pole piece, and increase the negative pole piece’s Active ion transmission sites can also ensure that the negative pole piece has low side reaction activity, thereby further improving the low-temperature charging performance and high-temperature cycle life of the battery.
- the negative electrode active material contains an appropriate amount of natural graphite, which can also enable the negative electrode active material to have a higher gram capacity, and can increase the compaction density of the negative electrode membrane, thereby increasing the energy density of the battery.
- the mass ratio of natural graphite in the negative electrode active material is 30%-50%. More preferably, it is 35% to 50%.
- the mass ratio of natural graphite in the negative active material is 25%, 30%, 35%, 40% or 45%.
- the average particle size D V 50 of the negative active material is 15 ⁇ m to 19 ⁇ m, more preferably 16 ⁇ m to 18 ⁇ m.
- the D v 50 of the negative electrode active material is in an appropriate range, which can ensure its high gram capacity while reducing the side reactions that occur on the surface of the negative electrode piece, and shorten the migration path of active ions and electrons in the particles to make it active Ions and electrons have a higher migration rate in the negative pole piece, so that the battery has a higher energy density, while improving the high-temperature cycle life and low-temperature charging performance.
- the volume average particle size D v 50 of the artificial graphite is preferably 14 ⁇ m to 18 ⁇ m, preferably 15 ⁇ m to 17 ⁇ m .
- the volume average particle diameter D v 50 of natural graphite is preferably 15 ⁇ m to 19 ⁇ m, and preferably 16 ⁇ m to 18 ⁇ m.
- the D v 50 of natural graphite in an appropriate range can also increase the peak intensity of the X-ray diffraction peaks of the 3R phase crystal planes (such as the 012 crystal plane and/or the 101 crystal plane) of the negative electrode active material in the negative electrode, and increase the negative electrode
- the active ion transmission sites of the sheet can also ensure that the negative electrode sheet has lower side reaction activity, thereby helping to improve the low-temperature charging performance and high-temperature cycle life of the battery.
- the tap density of the negative active material is less than 1.1 g/cm 3 , preferably 1.0 g/cm 3 to 1.09 g/cm 3 .
- the tap density of the negative electrode active material is within an appropriate range, and the negative electrode diaphragm using it can obtain a higher compaction density, and can have a higher active ion and electron transport performance, thereby improving the energy density and low-temperature charging performance of the battery .
- the negative pole piece can also have higher cohesion and adhesion, which can reduce the volume expansion of the battery during high-temperature cycling, thereby also improving the high-temperature cycle life of the battery.
- the tap density of the artificial graphite is 0.9 g/cm 3 to 1.1 g/cm 3 , It is more preferably 0.95g/cm 3 ⁇ 1.05g/cm 3 ; the tap density of natural graphite is 0.90g/cm 3 ⁇ 1.15g/cm 3 , more preferably 0.9g/cm 3 ⁇ 1.1g/cm 3 , especially It is preferably 1.0 g/cm 3 to 1.1 g/cm 3 .
- the graphitization degree of the negative electrode active material is 92%-95%, preferably 93%-94%.
- the graphitization degree of the negative electrode active material is in an appropriate range, which can make it have a higher gram capacity and a larger interlayer spacing, which reduces the diffusion resistance of active ions in the interior.
- the contact area between the negative electrode active material particles and between the negative electrode active material and the negative electrode current collector is relatively large, which can further improve the transmission of active ions and electrons inside the negative electrode piece.
- the negative pole piece can also have higher cohesion and adhesion, and can further improve the high temperature cycle performance of the battery using it.
- the graphitization degree of the artificial graphite is preferably 90%-95%, more preferably 91%-93 %.
- the degree of graphitization of natural graphite may be 95%-98.5%, preferably 95%-98%, and more preferably 96%-97%.
- the positive electrode active material includes one or more of olivine-structured lithium-containing phosphate and its modified compounds
- the negative electrode active material includes both artificial graphite and natural graphite, and the negative electrode piece satisfies 0.04 ⁇ I When 3R(012) /I 2H(100) ⁇ 0.22, if the negative electrode membrane still meets one or more of the following conditions, the performance of the battery can be further improved.
- the positive electrode active material includes one or more of lithium iron phosphate, a composite material of lithium iron phosphate and carbon, and modified compounds thereof.
- the areal density of the negative electrode film is 7 mg/cm 2 to 10 mg/cm 2 , more preferably 7 mg/cm 2 to 8 mg/cm 2 .
- the battery can have a higher energy density.
- the battery also has better active ion and electron transmission performance, thereby further improving the low-temperature charging performance of the battery.
- polarization and side reactions can be reduced, thereby further improving the high-temperature cycle performance of the battery.
- the compacted density of the negative electrode film is 1.5 g/cm 3 to 1.7 g/cm 3 , more preferably 1.55 g/cm 3 to 1.6 g/cm 3 .
- the compaction density of the negative electrode film is within the given range, it can ensure that the battery has a higher energy density.
- the particles of the negative electrode active material are closely packed, which can effectively reduce the resistance of the negative electrode membrane, thereby further improving the low-temperature charging performance of the battery.
- the proper compaction density can also protect the integrity of the negative electrode active material particle structure, which is beneficial to improve the cohesion and adhesion of the negative electrode pieces, reduce the expansion and side reactions during the battery cycle, and further improve the cycle life of the battery And safety performance.
- the I 3R ( 012) /I 2H(100) and I 3R(101) /I 2H(101) are within the required range.
- the selection of artificial graphite and natural graphite may independently include but not limited to one or more of their graphitization degree, particle size distribution, tap density, surface coating modification, and the like.
- the negative electrode active material may also include one or more of hard carbon, soft carbon, silicon-based material, and tin-based material.
- the negative electrode membrane may further include a binder.
- the binder used for the negative electrode membrane can be selected from polyacrylic acid (PAA), sodium polyacrylate (PAAS), polyacrylamide (PAM), polyvinyl alcohol (PVA), styrene butadiene rubber (SBR), seaweed One or more of sodium (SA), polymethacrylic acid (PMAA) and carboxymethyl chitosan (CMCS).
- the negative electrode membrane optionally further includes a thickener.
- the thickener may be sodium carboxymethyl cellulose (CMC-Na).
- the negative electrode membrane optionally further includes a conductive agent.
- the conductive agent used for the negative electrode film may be selected from one or more of superconducting carbon, acetylene black, carbon black, Ketjen black, carbon dots, carbon nanotubes, graphene, and carbon nanofibers.
- each negative electrode membrane all refer to the parameter range of a single-sided membrane.
- the membrane parameters on any one of the surfaces meet the requirements of the present application, that is, it is considered to fall within the protection scope of the present application.
- the ranges of I 3R(012) /I 2H(100) , I 3R(101) /I 2H(101) , compaction density, areal density, etc., mentioned in this application all refer to cold compaction and use for assembly The parameter range of the secondary battery.
- the peak intensity of the X-ray diffraction peak is the integral of the corresponding diffraction peak Expressed by area.
- the peak intensities of the X-ray diffraction peaks I 3R(012) , I 2H(100) , I 3R(101) , and I 2H(101) can all be measured using instruments and methods known in the art. For example, an X-ray powder diffractometer measures the X-ray diffraction spectrum in accordance with JIS K0131-1996 X-ray Diffraction Analysis General Rules.
- the 2 ⁇ angle corresponding to the 012 crystal plane of the 3R phase of the negative electrode active material is 46.03° ⁇ 46.63° (for example, 46.33°); the 2 ⁇ angle corresponding to the 100 crystal plane of the 2H phase is 42.06° ⁇ 42.66° (for example, 42.36°); the 3R phase
- the 2 ⁇ angle corresponding to the 101 crystal plane is 43.15° to 43.75° (for example, 43.45°); the 2 ⁇ angle corresponding to the 2H phase 101 crystal plane is 44.16° to 44.76° (for example, 44.46°).
- the degree of graphitization is a well-known meaning in the art, and it can be measured with a well-known instrument and method in the art.
- an X-ray powder diffractometer such as PANalytical X'pert PRO
- d 002 is the interlayer spacing in the crystal structure of the graphite material in nanometers.
- the volume average particle size D v 50 is a well-known meaning in the art, and it represents the particle size corresponding to the cumulative volume distribution percentage of the material reaching 50%, and can be measured with instruments and methods known in the art. For example, you can refer to the GB/T 19077-2016 particle size distribution laser diffraction method, and use a laser particle size analyzer for easy determination, such as the Mastersizer 2000E laser particle size analyzer of Malvern Instruments Co., Ltd., UK.
- the tap density is a well-known meaning in the art, and can be tested by methods known in the art. For example, you can refer to the standard GB/T 5162-2006 and use a powder tap density tester (such as Dandong Baxter BT-301) for testing.
- a powder tap density tester such as Dandong Baxter BT-301
- the compaction density of the negative electrode film is a well-known meaning in the art, and can be measured with a well-known instrument and method in the art. For example, take a negative electrode piece coated on one side and cold pressed to test the thickness of the negative electrode membrane, and then test the areal density of the negative electrode membrane according to the above method.
- the compaction density of the negative electrode membrane the areal density of the negative electrode membrane/ The thickness of the negative electrode membrane.
- the electrolyte conducts ions between the positive pole piece and the negative pole piece.
- the type of electrolyte in this application can be selected according to requirements.
- the electrolyte may be selected from at least one of solid electrolytes and liquid electrolytes (ie, electrolytes).
- an electrolyte is used as the electrolyte.
- the electrolyte includes electrolyte salt and solvent.
- the electrolyte salt may be selected from LiPF 6 (lithium hexafluorophosphate), LiBF 4 (lithium tetrafluoroborate), LiClO 4 (lithium perchlorate), LiAsF 6 (lithium hexafluoroarsenate), LiFSI (difluorosulfonate) Lithium imide), LiTFSI (lithium bistrifluoromethanesulfonimide), LiTFS (lithium trifluoromethanesulfonate), LiDFOB (lithium difluorooxalate), LiBOB (lithium bisoxalate), LiPO 2 F 2 (Lithium difluorophosphate), LiDFOP (lithium difluorodioxalate phosphate) and LiTFOP (lithium tetrafluorooxalate phosphate) one or more.
- LiPF 6 lithium hexafluorophosphate
- LiBF 4 lithium tetrafluoroborate
- the solvent may be selected from ethylene carbonate (EC), propylene carbonate (PC), ethyl methyl carbonate (EMC), diethyl carbonate (DEC), dimethyl carbonate (DMC), Dipropyl carbonate (DPC), methyl propyl carbonate (MPC), ethylene propyl carbonate (EPC), butylene carbonate (BC), fluoroethylene carbonate (FEC), methyl formate (MF), methyl acetate Ester (MA), ethyl acetate (EA), propyl acetate (PA), methyl propionate (MP), ethyl propionate (EP), propyl propionate (PP), methyl butyrate (MB) , Ethyl butyrate (EB), 1,4-butyrolactone (GBL), sulfolane (SF), dimethyl sulfone (MSM), methyl ethyl sulfone (EMS) and diethyl sulfone (ESE) one
- the electrolyte may also optionally include additives.
- the additives can include negative electrode film-forming additives, positive electrode film-forming additives, and additives that can improve certain battery performance, such as additives that improve battery overcharge performance, additives that improve battery high-temperature performance, and battery low-temperature performance. Additives, etc.
- the isolation film is arranged between the positive pole piece and the negative pole piece to play a role of isolation.
- the isolation film may be selected from one of glass fiber films, non-woven films, polyethylene (PE) films, polypropylene (PP) films, polyvinylidene fluoride films, and their multilayer composite films. kind or several kinds.
- Fig. 1 shows a secondary battery 5 with a square structure as an example.
- the secondary battery may include an outer package.
- the outer packaging is used to encapsulate the positive pole piece, the negative pole piece and the electrolyte.
- the outer package may include a housing 51 and a cover 53.
- the housing 51 may include a bottom plate and a side plate connected to the bottom plate, and the bottom plate and the side plate enclose a receiving cavity.
- the housing 51 has an opening communicating with the accommodating cavity, and a cover plate 53 can cover the opening to close the accommodating cavity.
- the positive pole piece, the negative pole piece, and the separator may be formed into the electrode assembly 52 through a lamination process or a winding process.
- the electrode assembly 52 is packaged in the receiving cavity.
- the electrolyte may be an electrolyte, and the electrolyte is infiltrated in the electrode assembly 52.
- the number of electrode assemblies 52 included in the secondary battery 5 can be one or several, which can be adjusted according to requirements.
- the outer packaging of the secondary battery may be a hard case, such as a hard plastic case, aluminum case, steel case, or the like.
- the outer packaging of the secondary battery may also be a soft bag, such as a pouch type soft bag.
- the material of the soft bag may be plastic, for example, it may include one or more of polypropylene (PP), polybutylene terephthalate (PBT), polybutylene succinate (PBS), and the like.
- the secondary battery can be assembled into a battery module, and the number of secondary batteries contained in the battery module can be multiple, and the specific number can be adjusted according to the application and capacity of the battery module.
- FIG. 3 is a battery module 4 as an example.
- a plurality of secondary batteries 5 may be arranged in sequence along the length direction of the battery module 4. Of course, it can also be arranged in any other manner. Furthermore, the plurality of secondary batteries 5 can be fixed by fasteners.
- the battery module 4 may further include a housing having an accommodating space, and a plurality of secondary batteries 5 are accommodated in the accommodating space.
- the above-mentioned battery modules can also be assembled into a battery pack, and the number of battery modules contained in the battery pack can be adjusted according to the application and capacity of the battery pack.
- FIGS 4 and 5 show the battery pack 1 as an example. 4 and 5, the battery pack 1 may include a battery box and a plurality of battery modules 4 provided in the battery box.
- the battery box includes an upper box body 2 and a lower box body 3.
- the upper box body 2 can be covered on the lower box body 3 and forms a closed space for accommodating the battery module 4.
- a plurality of battery modules 4 can be arranged in the battery box in any manner.
- the preparation method of the secondary battery may include a step of assembling the negative electrode tab, the positive electrode tab, and the electrolyte to form a secondary battery.
- the positive pole piece, the separator film, and the negative pole piece can be wound or laminated in order, so that the separator film is located between the positive pole piece and the negative pole piece to isolate the electrode assembly (ie Battery); Put the electrode assembly in the outer package, inject the electrolyte and seal to obtain the secondary battery.
- the preparation of the secondary battery may further include a step of preparing a positive pole piece.
- the positive electrode active material, conductive agent, and binder can be dispersed in a solvent (for example, N-methylpyrrolidone, NMP for short) to form a uniform positive electrode slurry; the positive electrode slurry can be coated on the positive electrode current collector, After drying, cold pressing and other processes, a positive pole piece is obtained.
- a solvent for example, N-methylpyrrolidone, NMP for short
- the preparation of the secondary battery may further include the step of preparing a negative electrode piece.
- a negative electrode piece As an example, disperse the negative electrode active material, binder, and optional thickener and conductive agent in a solvent.
- the solvent can be deionized water to form a uniform negative electrode slurry; the negative electrode slurry is coated on the negative electrode collector. On the fluid, after drying, cold pressing and other processes, the negative pole piece is obtained.
- the second aspect of the present application provides a device, which includes any one or several secondary batteries of the first aspect of the present application.
- the secondary battery can be used as a power source of the device, and can also be used as an energy storage unit of the device.
- the device can be, but is not limited to, mobile devices (such as mobile phones, laptop computers, etc.), electric vehicles (such as pure electric vehicles, hybrid electric vehicles, plug-in hybrid electric vehicles, electric bicycles, electric scooters, electric golf Vehicles, electric trucks, etc.), electric trains, ships and satellites, energy storage systems, etc.
- the device can select a secondary battery, a battery module, or a battery pack according to its usage requirements.
- Figure 6 is a device as an example.
- the device is a pure electric vehicle, a hybrid electric vehicle, or a plug-in hybrid electric vehicle, etc.
- a battery pack or a battery module can be used.
- the device may be a mobile phone, a tablet computer, a notebook computer, and the like.
- the device is generally required to be thin and light, and a secondary battery can be used as a power source.
- the positive electrode active material LiNi 0.8 Co 0.1 Mn 0.1 O 2 (abbreviated as NCM811), the conductive agent Super P, and the binder PVDF are mixed in an appropriate amount of NMP at a mass ratio of 96.5:1.5:2 to form a uniform positive electrode. Slurry; The positive electrode slurry is coated on the surface of the positive electrode current collector aluminum foil, and after drying and cold pressing, the positive electrode piece is obtained.
- Ethylene carbonate (EC), ethyl methyl carbonate (EMC), and diethyl carbonate (DEC) are mixed in a volume ratio of 1:1:1, and then LiPF 6 is uniformly dissolved in the above solution to obtain an electrolyte.
- the concentration of LiPF 6 is 1 mol/L.
- the positive pole piece, separator film, and negative pole piece are stacked and wound in order to obtain the electrode assembly; put the electrode assembly into the outer package, add the electrolyte prepared above, and go through the processes of encapsulation, standing, chemical conversion, and aging. , Get a secondary battery.
- the preparation method is similar to Example 1, but the difference is: adjust the relevant parameters in the preparation step of the negative pole piece, see Table 1 and Table 2 for details; and replace the positive electrode active materials of Examples 14-27 and Comparative Examples 3-4 It is lithium iron phosphate (abbreviated as LFP); thus, the corresponding secondary battery is prepared.
- LFP lithium iron phosphate
- the discharge cut-off voltage is 2.8V, and the charge cut-off voltage is 4.2V; when the positive electrode active material is lithium iron phosphate LFP, the discharge cut-off voltage is 2.5V, The charge cut-off voltage is 3.65V.
- the negative electrode activity of the negative pole piece includes both artificial graphite and natural graphite, and the negative pole piece satisfies 0.02 ⁇ I 3R(012) /I 2H(100) ⁇ 0.18, especially if it satisfies 0.04 ⁇ I 3R(012) /I 2H(100) ⁇ 0.12, Under the premise of higher energy density, the secondary battery can also take into account higher high-temperature cycle performance and higher low-temperature charging performance.
- the comparison result of Examples 14-27 and Comparative Example 3-4 shows that when the positive pole piece includes one or more of the olivine structure lithium-containing phosphate and its modified compounds, the negative electrode activity of the negative pole piece
- the material contains both artificial graphite and natural graphite, and the negative pole piece satisfies 0.04 ⁇ I 3R(012) /I 2H(100) ⁇ 0.22, especially if it satisfies 0.06 ⁇ I 3R(012) /I 2H(100) ⁇ 0.18,
- the secondary battery can also take into account higher high-temperature cycle performance and higher low-temperature charging performance.
- the negative electrode active material of the negative pole piece includes both artificial graphite and natural graphite, and natural graphite is active in the negative electrode.
- the mass ratio in the material is within a specific range, the low-temperature charging performance and high-temperature cycle performance of the battery can be further improved.
- the negative electrode active material of the negative pole piece includes both artificial graphite and natural graphite, and the compaction density of the negative electrode diaphragm And/or when the areal density is within a specific range, the low-temperature charging performance and high-temperature cycle performance of the battery can be further improved.
Abstract
Description
Claims (15)
- 一种二次电池,包括正极极片和负极极片,所述正极极片包括正极集流体以及设置在所述正极集流体至少一个表面上且包括正极活性材料的正极膜片,所述负极极片包括负极集流体以及设置在所述负极集流体至少一个表面上且包括负极活性材料的负极膜片,其中,所述正极活性材料包括层状锂过渡金属氧化物及其改性化合物中的一种或几种;所述负极活性材料包括人造石墨和天然石墨,且所述负极极片满足:0.02≤I 3R(012)/I 2H(100)≤0.18,优选地,0.04≤I 3R (012)/I 2H(100)≤0.12;其中,所述I 3R(012)为所述负极极片中所述负极活性材料的3R相012晶面的X射线衍射峰的峰强度,所述I 2H(100)为所述负极极片中所述负极活性材料的2H相100晶面的X射线衍射峰的峰强度。
- 根据权利要求1所述的二次电池,其中,所述负极极片还满足:0.02≤I 3R(101)/I 2H(101)≤0.18;优选地,0.04≤I 3R(101)/I 2H(101)≤0.12;其中,所述I 3R(101)为所述负极极片中所述负极活性材料的3R相101晶面的X射线衍射峰的峰强度,所述I 2H(101)为所述负极极片中所述负极活性材料的2H相101晶面的X射线衍射峰的峰强度。
- 根据权利要求1或2所述的二次电池,其中,所述天然石墨在所述负极活性材料中的质量占比≤50%,优选为15%~25%。
- 根据权利要求1-3任一项所述的二次电池,其中,所述负极活性材料的平均粒径D V50为11μm~15μm,优选为12μm~14μm。
- 根据权利要求1-4任一项所述的二次电池,其中,所述负极活性材料的振实密度≥1.1g/cm 3,优选为1.1g/cm 3~1.15g/cm 3;和/或,所述负极活性材料的石墨化度为92%~96%,优选为93%~95%。
- 根据权利要求1-5任一项所述的二次电池,其中,所述负极膜片的面密度为10mg/cm 2~13mg/cm 2,优选为10.5mg/cm 2~11.5mg/cm 2;和/或,所述负极膜片的压实密度为1.6g/cm 3~1.8g/cm 3,优选为1.65g/cm 3~1.7g/cm 3。
- 根据权利要求1-6任一项所述的二次电池,其中,所述层状锂过渡金属氧化物包括锂镍钴锰氧化物、锂镍钴铝氧化物及其改性化合物中的一种或几种。
- 一种二次电池,包括正极极片和负极极片,所述正极极片包括正极集流体以及设置在所述正极集流体至少一个表面上且包括正极活性材料的正极膜片,所述负极极片包括负极集流体以及设置在所述负极集流体至少一个表面上且包括负极活性材料的负极膜片,其中,所述正极活性材料包括橄榄石结构的含锂磷酸盐及其改性化合物中的一种或几种;所述负极活性材料包括人造石墨和天然石墨,且所述负极极片满足:0.04≤I 3R(012)/I 2H(100)≤0.22,优选地,0.06≤I 3R(012)/I 2H(100)≤0.18;其中,所述I 3R(012)为所述负极极片中所述负极活性材料的3R相012晶面的X射线衍射峰的峰强度,所述I 2H(100)为所述负极极片中所述负极活性材料的2H相100晶面的X射线衍射峰的峰强度。
- 根据权利要求8所述的二次电池,其中,所述负极极片还满足:0.04≤I 3R(101)/I 2H(101)≤0.22;优选地,0.06≤I 3R(101)/I 2H(101)≤0.18;其中,所述I 3R(101)为所述负极极片中所述负极活性材料的3R相101晶面的X射线衍射峰的峰强度,所述I 2H(101)为所述负极极片中所述负极活性材料的2H相101晶面的X射线衍射峰的峰强度。
- 根据权利要求8或9所述的二次电池,其中,所述天然石墨在所述负极活性材料中的质量占比≥20%,优选为35%~50%。
- 根据权利要求8-10任一项所述的二次电池,其中,所述负极活性材料的平均粒径D V50为15μm~19μm,优选为16μm~18μm。
- 根据权利要求8-11任一项所述的二次电池,其中,所述负极活性材料的振实密度<1.1g/cm 3,优选为1.0g/cm 3~1.09g/cm 3;和/或,所述负极活性材料的石墨化度为92%~95%,优选为93%~94%。
- 根据权利要求8-12任一项所述的二次电池,其中,所述负极膜片的面密度为7mg/cm 2~10mg/cm 2,优选为7mg/cm 2~8mg/cm 2;和/或,所述负极膜片的压实密度为1.5g/cm 3~1.7g/cm 3,优选为1.55g/cm 3~1.6g/cm 3。
- 根据权利要求8-13任一项所述的二次电池,其中,所述橄榄石结构的含锂磷酸盐包括磷酸铁锂、磷酸铁锂与碳的复合材料及其改性化合物中的一种或几种。
- 一种装置,包括权利要求1-14任一项所述的二次电池。
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KR1020217030668A KR102599884B1 (ko) | 2020-03-27 | 2020-03-27 | 이차 전지 및 이차 전지를 포함하는 장치 |
CN202310314181.4A CN116247202A (zh) | 2020-03-27 | 2020-03-27 | 二次电池和包含二次电池的装置 |
EP20927265.7A EP3951943B1 (en) | 2020-03-27 | 2020-03-27 | Secondary battery and apparatus contained the secondary battery |
PL20927265.7T PL3951943T3 (pl) | 2020-03-27 | 2020-03-27 | Bateria wtórna i aparat zawierający baterię wtórną |
EP23194553.6A EP4276965A3 (en) | 2020-03-27 | 2020-03-27 | Secondary cell, and device comprising secondary cell |
EP22216320.6A EP4191709A1 (en) | 2020-03-27 | 2020-03-27 | Secondary battery and apparatus contained the secondary battery |
JP2021554747A JP7174863B2 (ja) | 2020-03-27 | 2020-03-27 | 二次電池及び二次電池を備える装置 |
CN202080005610.4A CN113748539B (zh) | 2020-03-27 | 2020-03-27 | 二次电池和包含二次电池的装置 |
PCT/CN2020/081691 WO2021189425A1 (zh) | 2020-03-27 | 2020-03-27 | 二次电池和包含二次电池的装置 |
US17/542,533 US11437623B2 (en) | 2020-03-27 | 2021-12-06 | Secondary battery and apparatus contained the secondary battery |
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CN114447270A (zh) * | 2021-12-28 | 2022-05-06 | 华为数字能源技术有限公司 | 一种负极极片、电池和电子设备 |
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EP4276965A3 (en) | 2024-01-03 |
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PL3951943T3 (pl) | 2024-04-02 |
US20220093925A1 (en) | 2022-03-24 |
KR20210130780A (ko) | 2021-11-01 |
CN113748539A (zh) | 2021-12-03 |
EP4191709A1 (en) | 2023-06-07 |
CN116247202A (zh) | 2023-06-09 |
US11437623B2 (en) | 2022-09-06 |
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