WO2024040504A1 - 二次电池、其制备方法及包含其的用电装置 - Google Patents

二次电池、其制备方法及包含其的用电装置 Download PDF

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WO2024040504A1
WO2024040504A1 PCT/CN2022/114750 CN2022114750W WO2024040504A1 WO 2024040504 A1 WO2024040504 A1 WO 2024040504A1 CN 2022114750 W CN2022114750 W CN 2022114750W WO 2024040504 A1 WO2024040504 A1 WO 2024040504A1
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nitrate
negative electrode
secondary battery
weight
lithium
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PCT/CN2022/114750
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English (en)
French (fr)
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杨成龙
张海明
唐代春
喻鸿钢
高靖宇
刘醒醒
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宁德时代新能源科技股份有限公司
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Priority to PCT/CN2022/114750 priority Critical patent/WO2024040504A1/zh
Publication of WO2024040504A1 publication Critical patent/WO2024040504A1/zh

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    • H—ELECTRICITY
    • H01—ELECTRIC ELEMENTS
    • H01M—PROCESSES OR MEANS, e.g. BATTERIES, FOR THE DIRECT CONVERSION OF CHEMICAL ENERGY INTO ELECTRICAL ENERGY
    • H01M10/00—Secondary cells; Manufacture thereof
    • H01M10/05—Accumulators with non-aqueous electrolyte
    • H01M10/052—Li-accumulators
    • H01M10/0525—Rocking-chair batteries, i.e. batteries with lithium insertion or intercalation in both electrodes; Lithium-ion batteries
    • H—ELECTRICITY
    • H01—ELECTRIC ELEMENTS
    • H01M—PROCESSES OR MEANS, e.g. BATTERIES, FOR THE DIRECT CONVERSION OF CHEMICAL ENERGY INTO ELECTRICAL ENERGY
    • H01M10/00—Secondary cells; Manufacture thereof
    • H01M10/05—Accumulators with non-aqueous electrolyte
    • H01M10/056—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
    • H—ELECTRICITY
    • H01—ELECTRIC ELEMENTS
    • H01M—PROCESSES OR MEANS, e.g. BATTERIES, FOR THE DIRECT CONVERSION OF CHEMICAL ENERGY INTO ELECTRICAL ENERGY
    • H01M10/00—Secondary cells; Manufacture thereof
    • H01M10/05—Accumulators with non-aqueous electrolyte
    • H01M10/058—Construction or manufacture
    • H—ELECTRICITY
    • H01—ELECTRIC ELEMENTS
    • H01M—PROCESSES OR MEANS, e.g. BATTERIES, FOR THE DIRECT CONVERSION OF CHEMICAL ENERGY INTO ELECTRICAL ENERGY
    • H01M10/00—Secondary cells; Manufacture thereof
    • H01M10/36—Accumulators not provided for in groups H01M10/05-H01M10/34
    • H—ELECTRICITY
    • H01—ELECTRIC ELEMENTS
    • H01M—PROCESSES OR MEANS, e.g. BATTERIES, FOR THE DIRECT CONVERSION OF CHEMICAL ENERGY INTO ELECTRICAL ENERGY
    • H01M4/00—Electrodes
    • H01M4/02—Electrodes composed of, or comprising, active material
    • H01M4/13—Electrodes for accumulators with non-aqueous electrolyte, e.g. for lithium-accumulators; Processes of manufacture thereof
    • 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
    • H01M4/62—Selection of inactive substances as ingredients for active masses, e.g. binders, fillers
    • Y—GENERAL TAGGING OF NEW TECHNOLOGICAL DEVELOPMENTS; GENERAL TAGGING OF CROSS-SECTIONAL TECHNOLOGIES SPANNING OVER SEVERAL SECTIONS OF THE IPC; TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS
    • Y02—TECHNOLOGIES OR APPLICATIONS FOR MITIGATION OR ADAPTATION AGAINST CLIMATE CHANGE
    • Y02E—REDUCTION OF GREENHOUSE GAS [GHG] EMISSIONS, RELATED TO ENERGY GENERATION, TRANSMISSION OR DISTRIBUTION
    • Y02E60/00—Enabling technologies; Technologies with a potential or indirect contribution to GHG emissions mitigation
    • Y02E60/10—Energy storage using batteries

Definitions

  • the present application relates to the technical field of secondary batteries, and in particular to a secondary battery and its preparation method, as well as battery modules, battery packs and electrical devices containing the same.
  • lithium-ion batteries are widely used in energy storage power systems such as hydraulic, thermal, wind and solar power stations, as well as electric tools, electric bicycles, electric motorcycles, electric Automobiles, military equipment, aerospace and other fields. Due to the great development of lithium-ion batteries, higher requirements have been put forward for their cycle performance and safety performance.
  • lithium-ion secondary batteries after the battery undergoes multiple charge and discharge cycles, lithium will precipitate on the electrode, and the precipitated lithium may grow into lithium dendrites. Lithium dendrites can puncture the isolation film and cause thermal runaway of the battery core, thereby shortening the cycle life of the battery and even affecting the safety of the battery. Therefore, there is a need to suppress the growth of lithium dendrites during cycling of lithium-ion secondary batteries.
  • the present application was made in view of the above-mentioned problems, and an object thereof is to provide a secondary battery in which the formation of lithium dendrites during cycling is suppressed.
  • a first aspect of the present application provides a secondary battery, which includes a negative electrode sheet, the negative electrode sheet includes a negative electrode current collector and a negative electrode film layer disposed on at least one surface of the negative electrode current collector, so The negative electrode film layer contains nitrate.
  • this application can effectively inhibit the growth of lithium dendrites in lithium ion secondary batteries by adding nitrate to the negative electrode film layer of the battery.
  • the nitrate is selected from one or more of magnesium nitrate, copper nitrate, zinc nitrate, calcium nitrate, aluminum nitrate, silver nitrate, lithium nitrate, potassium nitrate and sodium nitrate;
  • the nitrate is selected from one or more of magnesium nitrate, copper nitrate, zinc nitrate, calcium nitrate and aluminum nitrate; further optionally, the nitrate is selected from one or more of magnesium nitrate, copper nitrate and zinc nitrate.
  • One or more species; further optionally, the nitrate is magnesium nitrate.
  • nitrate By selecting the type of nitrate, the effect of nitrate on inhibiting the growth of lithium dendrites can be further optimized.
  • the nitrate content in the negative electrode film layer is more than 0.2% by weight; optionally 0.2%-4.5% by weight; further optionally 0.2% by weight %-1.5% by weight.
  • the effect of nitrate on inhibiting the growth of lithium dendrites can be further optimized.
  • the negative electrode film layer includes a negative electrode active material
  • the negative electrode active material includes at least one of a carbon-based negative electrode active material and a silicon-based negative electrode active material.
  • lithium dendrites can be suppressed more significantly.
  • the secondary battery includes an electrolyte that also contains nitrate; optionally, the nitrate content in the electrolyte is 0.1% by weight based on the total weight of the electrolyte. above.
  • Nitrate in the electrolyte can inhibit the formation of lithium dendrites.
  • a second aspect of the application also provides a method for preparing a secondary battery, including preparing a negative electrode plate using the following steps:
  • a slurry containing a negative active material and a nitrate is applied to at least one surface of the negative current collector.
  • the nitrate is selected from one or more of magnesium nitrate, copper nitrate, zinc nitrate, calcium nitrate, aluminum nitrate, silver nitrate, lithium nitrate, potassium nitrate and sodium nitrate;
  • the nitrate is selected from one or more of magnesium nitrate, copper nitrate, zinc nitrate, calcium nitrate and aluminum nitrate; further optionally, the nitrate is selected from one or more of magnesium nitrate, copper nitrate and zinc nitrate.
  • One or more species; further optionally, the nitrate is magnesium nitrate.
  • nitrate By selecting the type of nitrate, the effect of nitrate on inhibiting the growth of lithium dendrites can be further optimized.
  • the content of the nitrate is more than 0.5% by weight, optionally 0.5%-5% by weight, further optionally 0.5%-2% by weight, based on the dry content of the slurry. Recount.
  • nitrate content added to the slurry By controlling the nitrate content added to the slurry, appropriate nitrate content in the negative electrode film layer and the electrolyte can be obtained.
  • the negative active material includes a carbon-based negative active material and/or a silicon-based negative active material.
  • lithium dendrites can be suppressed more significantly.
  • a third aspect of the present application provides an electrical device, including at least one selected from the secondary battery of the first aspect of the present application and a secondary battery obtained by the method of preparing a secondary battery of the second aspect of the present application. .
  • Figure 1 is a schematic diagram of the presumed principle of nitrate inhibiting lithium dendrites.
  • Figure 2 is a scanning electron microscope (SEM) characterization diagram of the lithium deposition area of the batteries of the Examples and Comparative Examples after cycling.
  • Example 3 is a partial enlarged view of a CCD (inductive coupling device) of the isolation film corresponding to the lithium deposition region in Comparative Example 1 (A) and Example 1 (B).
  • FIG. 4 is a schematic diagram of a secondary battery according to an embodiment of the present application.
  • FIG. 5 is an exploded view of the secondary battery according to the embodiment of the present application shown in FIG. 4 .
  • Figure 6 is a schematic diagram of a battery module according to an embodiment of the present application.
  • Figure 7 is a schematic diagram of a battery pack according to an embodiment of the present application.
  • FIG. 8 is an exploded view of the battery pack according to an embodiment of the present application shown in FIG. 7 .
  • FIG. 9 is a schematic diagram of a power consumption device using a secondary battery as a power source according to an embodiment of the present application.
  • Ranges disclosed herein are defined in terms of lower and upper limits. A given range is defined by selecting a lower limit and an upper limit that define the boundaries of the particular range. Ranges defined in this manner may be inclusive or exclusive of the endpoints, and may be arbitrarily combined, that is, any lower limit may be combined with any upper limit to form a range. For example, if ranges of 60-120 and 80-110 are listed for a particular parameter, understand that ranges of 60-110 and 80-120 are also expected. Furthermore, if the minimum range values 1 and 2 are listed, and if the maximum range values 3, 4, and 5 are listed, then the following ranges are all expected: 1-3, 1-4, 1-5, 2- 3, 2-4 and 2-5.
  • the numerical range “a-b” represents an abbreviated representation of any combination of real numbers between a and b, where a and b are both real numbers.
  • the numerical range “0-5" means that all real numbers between "0-5" have been listed in this article, and "0-5" is just an abbreviation of these numerical combinations.
  • a certain parameter is an integer ⁇ 2
  • the method includes steps (a) and (b), which means that the method may include steps (a) and (b) performed sequentially, or may include steps (b) and (a) performed sequentially.
  • step (c) means that step (c) may be added to the method in any order.
  • the method may include steps (a), (b) and (c). , may also include steps (a), (c) and (b), may also include steps (c), (a) and (b), etc.
  • condition "A or B” is satisfied by any of the following conditions: A is true (or exists) and B is false (or does not exist); A is false (or does not exist) and B is true (or exists) ; Or both A and B are true (or exist).
  • the inventor of the present application found that in lithium-ion secondary batteries using carbon-based materials and/or silicon-based materials as negative electrode active materials, the battery has obvious lithium dendrite growth after multiple charge and discharge cycles, and due to The solubility of nitrate in the electrolyte is very limited, so adding nitrate to the electrolyte cannot achieve a good effect of inhibiting the growth of lithium dendrites.
  • the present application proposes a secondary battery, which includes a negative electrode sheet, the negative electrode sheet includes a negative electrode current collector and a negative electrode film layer disposed on at least one surface of the negative electrode current collector, The negative electrode film contains nitrate.
  • the present application can effectively inhibit the growth of lithium dendrites in lithium ion secondary batteries by adding nitrate to the negative electrode film layer of the battery. After the battery has been cycled multiple times, even if lithium is precipitated on the electrode, the lithium is basically in a spherical state and will not grow into dendrites that can puncture the isolation film. It is speculated that one of the reasons why the present invention can effectively inhibit the growth of lithium dendrites is that the nitrate contained in the negative electrode can gradually diffuse into the electrolyte during the battery cycle, so that the electrolyte contains a sufficient amount of nitrate (for example, see Figure 1 schematic diagram shown).
  • the metal elements in the nitrate are reduced to form an alloy with lithium, which lowers the diffusion energy barrier and thus inhibits the formation of lithium dendrites.
  • the thickness of the SEI layer remains below 500 nm, thereby not significantly increasing the resistance.
  • the nitrate is selected from one or more of magnesium nitrate, copper nitrate, zinc nitrate, calcium nitrate, aluminum nitrate, silver nitrate, lithium nitrate, potassium nitrate and sodium nitrate;
  • the nitrate is selected from one or more of magnesium nitrate, copper nitrate, zinc nitrate, calcium nitrate and aluminum nitrate; further optionally, the nitrate is selected from one or more of magnesium nitrate, copper nitrate and zinc nitrate.
  • One or more species; further optionally, the nitrate is magnesium nitrate.
  • nitrate By selecting the type of nitrate, the effect of nitrate on inhibiting the growth of lithium dendrites can be further optimized.
  • the nitrate content in the negative electrode film layer is more than 0.2% by weight based on the total weight of the negative electrode film layer.
  • the nitrate content may be 0.3% by weight, 0.4% by weight, 0.5% by weight, 0.6% by weight, 1.5% by weight, 3.5% by weight, or within the range formed by any two of the above values; optionally, the nitrate content is 0.2% by weight - 4.5% by weight of nitrate, further optionally 0.2% by weight to 1.5% by weight.
  • nitrate content By selecting the nitrate content, the effect of nitrate on inhibiting the growth of lithium dendrites can be further optimized. If the content is less than 0.2% by weight, nitrate may be consumed faster in some cases, which is not conducive to long-term battery cycle. If the content is higher than 4.5% by weight, it will occupy more of the weight of the negative electrode film layer, which is not conducive to improving the energy density of the battery. Excessively high nitrate content may also cause anode film stripping.
  • the negative electrode film layer includes a negative electrode active material
  • the negative electrode active material includes at least one of a carbon-based negative electrode active material and a silicon-based negative electrode active material.
  • lithium dendrites can be suppressed more significantly.
  • the negative active material includes a carbon-based negative active material.
  • the carbon-based negative active material includes at least one of graphite, mesocarbon microspheres, soft carbon, and hard carbon.
  • the carbon-based negative active material is not particularly limited, and conventional carbon-based negative active materials in the art can be used.
  • a carbon-based negative active material with a Dv50 of 2-20 ⁇ m can be used.
  • the Dv50 range of hard carbon is 2-10 ⁇ m
  • the Dv50 range of graphite is 10-20 ⁇ m
  • the Dv50 range of soft carbon is 5-20 ⁇ m
  • the Dv50 range of mesocarbon microspheres is 10-20 ⁇ m.
  • the secondary battery includes an electrolyte that also contains nitrate; optionally, the nitrate content in the electrolyte is 0.1% by weight based on the total weight of the electrolyte. above.
  • Nitrate in the electrolyte can inhibit the formation of lithium dendrites.
  • the secondary battery is a lithium ion secondary battery.
  • This application also provides a method for preparing a secondary battery, including preparing a negative electrode plate using the following steps:
  • a slurry containing a negative active material and a nitrate is applied to at least one surface of the negative current collector.
  • the secondary battery prepared by the above method adds nitrate to the negative electrode film layer, the growth of lithium dendrites in the lithium ion secondary battery can be effectively suppressed.
  • adding nitrate to the slurry also facilitates the removal of crystal water usually contained in nitrate through the subsequent operation of drying the pole piece.
  • the content of the nitrate is above 0.5% by weight.
  • the content of the nitrate is 0.7% by weight, 1% by weight, 2% by weight, 4% by weight, 10% by weight, or at the above values. Within the range formed by any two of them, based on the dry weight of the slurry.
  • the content of the nitrate is 0.5% to 5% by weight, further optionally 0.5% to 2% by weight, based on the dry weight of the slurry.
  • nitrate content added to the slurry By controlling the nitrate content added to the slurry, appropriate nitrate content in the negative electrode film layer and the electrolyte can be obtained.
  • a secondary battery includes a positive electrode plate, a negative electrode plate, an electrolyte and a separator.
  • active ions are inserted and detached back and forth between the positive and negative electrodes.
  • the electrolyte plays a role in conducting ions between the positive and negative electrodes.
  • the isolation film is placed between the positive electrode piece and the negative electrode piece. It mainly prevents the positive and negative electrodes from short-circuiting and allows ions to pass through.
  • the positive electrode sheet includes a positive electrode current collector and a positive electrode film layer disposed on at least one surface of the positive electrode current collector.
  • the positive electrode film layer includes a positive electrode active material.
  • the positive electrode current collector has two surfaces facing each other in its own thickness direction, and the positive electrode film layer is disposed on any one or both of the two opposite surfaces of the positive electrode current collector.
  • the positive electrode current collector may be a metal foil or a composite current collector.
  • the metal foil aluminum foil can be used.
  • the composite current collector may include a polymer material base layer and a metal layer formed on at least one surface of the polymer material base layer.
  • Composite current collectors can be formed by forming metal materials (aluminum, aluminum alloys, nickel, nickel alloys, titanium, titanium alloys, silver and silver alloys, etc.) on polymer material substrates (such as polypropylene (PP), polyterephthalate It is formed on substrates such as ethylene glycol ester (PET), polybutylene terephthalate (PBT), polystyrene (PS), polyethylene (PE), etc.).
  • PP polypropylene
  • PBT polybutylene terephthalate
  • PS polystyrene
  • PE polyethylene
  • the cathode active material may be a cathode active material known in the art for batteries.
  • the cathode active material may include at least one of the following materials: an olivine-structured lithium-containing phosphate, a lithium transition metal oxide, and their respective modified compounds.
  • the present application is not limited to these materials, and other traditional materials that can be used as positive electrode active materials of batteries can also be used. Only one type of these positive electrode active materials may be used alone, or two or more types may be used in combination.
  • lithium transition metal oxides may include, but are not limited to, lithium cobalt oxides (such as LiCoO 2 ), lithium nickel oxides (such as LiNiO 2 ), lithium manganese oxides (such as LiMnO 2 , LiMn 2 O 4 ), lithium Nickel cobalt oxide, lithium manganese cobalt oxide, lithium nickel manganese oxide, lithium nickel cobalt manganese oxide (such as LiNi 1/3 Co 1/3 Mn 1/3 O 2 (also referred to as NCM 333 ), LiNi 0.5 Co 0.2 Mn 0.3 O 2 (can also be abbreviated to NCM 523 ), LiNi 0.5 Co 0.25 Mn 0.25 O 2 (can also be abbreviated to NCM 211 ), LiNi 0.6 Co 0.2 Mn 0.2 O 2 (can also be abbreviated to NCM 622 ), LiNi At least one of 0.8 Co 0.1 Mn 0.1 O 2 (also referred to as NCM 811 ), lithium nickel cobalt aluminum oxide (such as Li Li
  • the olivine structure contains Examples of lithium phosphates may include, but are not limited to, lithium iron phosphate (such as LiFePO 4 (also referred to as LFP)), composites of lithium iron phosphate and carbon, lithium manganese phosphate (such as LiMnPO 4 ), lithium manganese phosphate and carbon. At least one of composite materials, lithium iron manganese phosphate, and composite materials of lithium iron manganese phosphate and carbon.
  • lithium iron phosphate such as LiFePO 4 (also referred to as LFP)
  • composites of lithium iron phosphate and carbon such as LiMnPO 4
  • LiMnPO 4 lithium manganese phosphate and carbon.
  • At least one of composite materials, lithium iron manganese phosphate, and composite materials of lithium iron manganese phosphate and carbon At least one of composite materials, lithium iron manganese phosphate, and composite materials of lithium iron manganese phosphate and carbon.
  • the positive electrode film layer optionally further includes a binder.
  • the binder may include polyvinylidene fluoride (PVDF), polytetrafluoroethylene (PTFE), vinylidene fluoride-tetrafluoroethylene-propylene terpolymer, vinylidene fluoride-hexafluoropropylene-tetrafluoroethylene At least one of ethylene terpolymer, tetrafluoroethylene-hexafluoropropylene copolymer and fluorine-containing acrylate resin.
  • the positive electrode film layer optionally further includes a conductive agent.
  • the conductive agent may include at least one of superconducting carbon, acetylene black, carbon black, Ketjen black, carbon dots, carbon nanotubes, graphene and carbon nanofibers.
  • the positive electrode sheet can be prepared by dispersing the above-mentioned components for preparing the positive electrode sheet, such as positive active material, conductive agent, binder and any other components in a solvent (such as N -methylpyrrolidone) to form a positive electrode slurry; the positive electrode slurry is coated on the positive electrode current collector, and after drying, cold pressing and other processes, the positive electrode piece can be obtained.
  • a solvent such as N -methylpyrrolidone
  • the negative electrode sheet includes a negative electrode current collector and a negative electrode film layer disposed on at least one surface of the negative electrode current collector, where the negative electrode film layer includes a negative electrode active material.
  • the negative electrode current collector has two opposite surfaces in its own thickness direction, and the negative electrode film layer is disposed on any one or both of the two opposite surfaces of the negative electrode current collector.
  • the negative electrode current collector may be a metal foil or a composite current collector.
  • the composite current collector may include a polymer material base layer and a metal layer formed on at least one surface of the polymer material base material.
  • the composite current collector can be formed by forming metal materials (copper, copper alloy, nickel, nickel alloy, titanium, titanium alloy, silver and silver alloy, etc.) on a polymer material substrate (such as polypropylene (PP), polyterephthalate It is formed on substrates such as ethylene glycol ester (PET), polybutylene terephthalate (PBT), polystyrene (PS), polyethylene (PE), etc.).
  • PP polypropylene
  • PBT polybutylene terephthalate
  • PS polystyrene
  • PE polyethylene
  • the negative active material may be a carbon-based negative active material and/or a silicon-based negative active material.
  • the negative active material may include at least one of the following materials: artificial graphite, natural graphite, mesocarbon microspheres, soft carbon, hard carbon, silicon-based materials, and the like.
  • the silicon-based material may be selected from at least one of elemental silicon, silicon oxide compounds, silicon carbon composites, silicon nitrogen composites and silicon alloys. However, this application is not limited to these materials. Only one type of these negative electrode active materials may be used alone, or two or more types may be used in combination.
  • the negative electrode film layer optionally further includes a binder.
  • the binder can be selected from styrene-butadiene rubber (SBR), polyacrylic acid (PAA), polysodium acrylate (PAAS), polyacrylamide (PAM), polyvinyl alcohol (PVA), sodium alginate (SA), poly At least one of methacrylic acid (PMAA) and carboxymethyl chitosan (CMCS).
  • the negative electrode film layer optionally further includes a conductive agent.
  • the conductive agent may be selected from at least one of superconducting carbon, acetylene black, carbon black, Ketjen black, carbon dots, carbon nanotubes, graphene and carbon nanofibers.
  • the negative electrode film layer optionally includes other auxiliaries, such as thickeners (such as sodium carboxymethylcellulose (CMC-Na)) and the like.
  • thickeners such as sodium carboxymethylcellulose (CMC-Na)
  • the negative electrode sheet can be prepared by dispersing the above-mentioned components for preparing the negative electrode sheet, such as negative active materials, conductive agents, nitrates, binders and any other components in a solvent (for example, in deionized water), a negative electrode slurry is formed; the negative electrode slurry is coated on the negative electrode current collector, and after drying, cold pressing and other processes, the negative electrode piece can be obtained.
  • a solvent For example, in deionized water
  • a negative electrode slurry is formed; the negative electrode slurry is coated on the negative electrode current collector, and after drying, cold pressing and other processes, the negative electrode piece can be obtained.
  • the electrolyte plays a role in conducting ions between the positive and negative electrodes. This application has no specific restrictions on the type of electrolyte and can be selected according to needs.
  • the electrolyte solution includes electrolyte salts and solvents.
  • the electrolyte salt may be selected from the group consisting of lithium hexafluorophosphate, lithium tetrafluoroborate, lithium perchlorate, lithium hexafluoroarsenate, lithium bisfluorosulfonimide, lithium bistrifluoromethanesulfonimide, trifluoromethane At least one of lithium sulfonate, lithium difluorophosphate, lithium difluoroborate, lithium dioxaloborate, lithium difluorodioxalate phosphate and lithium tetrafluoroxalate phosphate.
  • the solvent may be selected from ethylene carbonate (EC), propylene carbonate, ethyl methyl carbonate, diethyl carbonate (DEC), dimethyl carbonate, dipropyl carbonate, methylpropyl carbonate , ethyl propyl carbonate, butylene carbonate, fluoroethylene carbonate, methyl formate, methyl acetate, ethyl acetate, propyl acetate, methyl propionate, ethyl propionate, propyl propionate, butyric acid At least one of methyl ester, ethyl butyrate, 1,4-butyrolactone, sulfolane, dimethyl sulfone, methyl ethyl sulfone and diethyl sulfone.
  • EC ethylene carbonate
  • DEC diethyl carbonate
  • DEC diethyl carbonate
  • fluoroethylene carbonate fluoroethylene carbonate
  • methyl formate methyl a
  • the electrolyte optionally further includes additives.
  • additives may include negative electrode film-forming additives, positive electrode film-forming additives, and may also include additives that can improve certain properties of the battery, such as additives that improve battery overcharge performance, additives that improve battery high-temperature or low-temperature performance, etc.
  • additives By using additives, the solubility of nitrate in the electrolyte can also be adjusted, thereby changing the nitrate content in the electrolyte.
  • the secondary battery further includes a separator film.
  • a separator film There is no particular restriction on the type of isolation membrane in this application. Any well-known porous structure isolation membrane with good chemical stability and mechanical stability can be used.
  • the material of the isolation membrane can be selected from at least one of glass fiber, non-woven fabric, polyethylene, polypropylene and polyvinylidene fluoride.
  • the isolation film can be a single-layer film or a multi-layer composite film, with no special restrictions. When the isolation film is a multi-layer composite film, the materials of each layer can be the same or different, and there is no particular limitation.
  • the positive electrode piece, the negative electrode piece and the separator film can be made into an electrode assembly through a winding process or a lamination process.
  • the secondary battery may include an outer packaging.
  • the outer packaging can be used to package the above-mentioned electrode assembly and electrolyte.
  • the outer packaging of the secondary battery may be a hard shell, such as a hard plastic shell, an aluminum shell, a steel shell, etc.
  • the outer packaging of the secondary battery may also be a soft bag, such as a bag-type soft bag.
  • the material of the soft bag may be plastic, and examples of the plastic include polypropylene, polybutylene terephthalate, polybutylene succinate, and the like.
  • FIG. 4 shows a square-structured secondary battery 5 as an example.
  • the outer package may include a housing 51 and a cover 53 .
  • the housing 51 may include a bottom plate and side plates connected to the bottom plate, and the bottom plate and the side plates enclose a receiving cavity.
  • the housing 51 has an opening communicating with the accommodation cavity, and the cover plate 53 can cover the opening to close the accommodation cavity.
  • the positive electrode piece, the negative electrode piece and the isolation film can be formed into the electrode assembly 52 through a winding process or a lamination process.
  • the electrode assembly 52 is packaged in the containing cavity.
  • the electrolyte soaks into the electrode assembly 52 .
  • the number of electrode assemblies 52 contained in the secondary battery 5 can be one or more, and those skilled in the art can select according to specific actual needs.
  • secondary batteries can be assembled into battery modules, and the number of secondary batteries contained in the battery module can be one or more. Those skilled in the art can select the specific number according to the application and capacity of the battery module.
  • FIG. 6 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 .
  • the plurality of secondary batteries 5 can be fixed by fasteners.
  • the battery module 4 may further include a housing having a receiving space in which a plurality of secondary batteries 5 are received.
  • the above-mentioned battery modules can also be assembled into a battery pack.
  • the number of battery modules contained in the battery pack can be one or more. Those skilled in the art can select the specific number according to the application and capacity of the battery pack.
  • the battery pack 1 may include a battery box and a plurality of battery modules 4 disposed in the battery box.
  • the battery box includes an upper box 2 and a lower box 3 .
  • the upper box 2 can be covered with the lower box 3 and form a closed space for accommodating the battery module 4 .
  • Multiple battery modules 4 can be arranged in the battery box in any manner.
  • the present application also provides an electrical device, which includes at least one of the secondary battery, battery module, or battery pack provided by the present application.
  • the secondary battery, battery module, or battery pack may be used as a power source for the electrical device, or may be used as an energy storage unit for the electrical device.
  • the electric device may include mobile devices (such as mobile phones, laptops, etc.), electric vehicles (such as pure electric vehicles, hybrid electric vehicles, plug-in hybrid electric vehicles, electric bicycles, electric scooters, and electric golf carts). , electric trucks, etc.), electric trains, ships and satellites, energy storage systems, etc., but are not limited to these.
  • a secondary battery, battery module or battery pack can be selected according to its usage requirements.
  • Figure 9 is an electrical device as an example.
  • the electric device is a pure electric vehicle, a hybrid electric vehicle, a plug-in hybrid electric vehicle, etc.
  • a battery pack or battery module can be used.
  • the device may be a mobile phone, a tablet, a laptop, etc.
  • the device is usually required to be thin and light, and a secondary battery can be used as a power source.
  • NCM 811 LiNi 0.8 Co 0.1 Mn 0.1 O 2
  • NMP N-methylpyrrolidone
  • Ethylene carbonate (EC) and diethyl carbonate (DEC) are mixed at a volume ratio of 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.
  • PE Polyethylene
  • Example 2 The other steps are the same as in Example 1 except that the amount of magnesium nitrate added is increased to 2% by weight and the amount of graphite is reduced to 95% by weight in the preparation of the negative electrode.
  • Example 2 The other steps are the same as in Example 1 except that the graphite is replaced with silicon-based material and the single-sided coating amount of the negative electrode is reduced from 0.15g/1540.25mm 2 to 0.05g/1540.25mm 2 .
  • Example 2 The other steps were the same as in Example 1 except that the graphite was replaced with hard carbon and the single-sided coating amount of the negative electrode was reduced from 0.15g/1540.25mm 2 to 0.135g/1540.25mm 2 .
  • Example 2 The other steps were the same as in Example 1 except that the graphite was replaced with mesophase carbon microspheres and the single-sided coating amount of the negative electrode was reduced from 0.15g/1540.25mm 2 to 0.13g/1540.25mm 2 .
  • Comparative Example 1 The preparation steps of Comparative Example 1 are similar to Example 1, except that magnesium nitrate is not added to the negative electrode and graphite is increased to 97% by weight.
  • Comparative Example 1 The preparation steps of Comparative Example 1 are similar to those of Example 1, except that no magnesium nitrate is added to the negative electrode, and the graphite is increased to 97% by weight; 1.2% by weight of magnesium nitrate is added to the electrolyte.
  • the 2C direct charging process that is, charge the lithium-ion battery to 4.25V at a constant current of 2C at 25°C, then charge at a constant voltage of 4.25V until the current drops to 0.05C, and then discharge it to 2.8V at a constant current of 1C , cycle through this to cause lithium to precipitate on the surface of the negative electrode.
  • the batteries prepared above were cycled for 600 cycles and 1500 cycles respectively. Then the battery in the fully charged state was disassembled, and the morphology of lithium precipitation was observed through SEM and the condition of the isolation film was observed through CCD. Among them, the lithium precipitation morphology is graded by visual inspection of SEM images.
  • “Flat” means that there are almost no protrusions on the surface of the pole piece
  • “slightly raised” means that there are visible but low-height protrusions on the surface of the pole piece.
  • “Obvious bulges” means that there are relatively high bulges on the surface of the pole piece, and “lithium dendrites” means that lithium precipitation in the form of dendrites appears on the surface of the pole piece.
  • Figure 2 shows a scanning electron microscope (SEM) image of the lithium evolution area of the batteries of Examples and Comparative Examples after cycling.
  • Picture (a) is a scanning electron microscope (SEM) picture of the lithium deposition area of the batteries of Example 10 (A), Example 8 (B) and Example 1 (C) after 1500 cycles.
  • the dotted line in the figure represents the horizontal plane of the pole piece surface. It can be seen that A has obvious bulges, B has slight bulges, and C is flat with basically no bulges. All three have approximately spherical morphology, that is, no dendrites are formed.
  • FIG. (b) of Figure 2 is a scanning electron microscope (SEM) image of the lithium deposition area of Comparative Example 1 (A) and Example 1 (B) after 600 cycles, using a higher magnification. It can be seen from the figure that the lithium precipitation morphology of Example 1 is spherical, while the lithium precipitation morphology of Comparative Example 1 is dendrite.
  • Figure 3 shows a partially enlarged CCD view of the isolation film corresponding to the lithium evolution area after 600 cycles of Comparative Example 1 (A) and Example 1 (B). It can be seen from the figure that the isolation film of Comparative Example 1 has lithium precipitation puncture holes, while the isolation film of Example 1 remains intact.
  • the nitrate content in the negative electrode was confirmed by ICP testing corresponding to the metal content.
  • the specific operation method is: disassemble the prepared battery after formation, take a certain area of the negative electrode plate, weigh it, and then digest it with concentrated nitric acid. Then, after diluting the solution, test the weight of the metal in the diluted solution through ICP. Calculate the nitrate content in the negative electrode film layer based on the tested metal weight and based on the weight of the negative electrode film layer (that is, the weight of the weighed pole piece minus the weight of the substrate).
  • the concentration of nitrate in the electrolyte was measured by ICP. After the prepared battery is formed, the battery is disassembled, the electrolyte is diluted, and the concentration of nitrate metal ions is tested by ICP to convert the nitrate concentration.
  • the thickness of the SEI layer is determined by argon ion polishing technology combined with SEM for ion polishing cross-sectional morphology analysis. Since the color of the negative electrode film layer in the SEM image is obviously darker than that of the SEI film, the difference between the two can be determined by the color difference. boundary line, from which the thickness of the SEI layer on the surface of the negative electrode film layer can be measured.

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Abstract

本申请提供一种二次电池，其包含负极极片，所述负极极片包含负极集流体以及设置在负极集流体至少一个表面上的负极膜层，所述负极膜层中含有硝酸盐。本申请的二次电池能够避免循环过程中锂枝晶的产生。本申请还提供包含该二次电池的用电装置。

Description

二次电池、其制备方法及包含其的用电装置 技术领域
本申请涉及二次电池技术领域，尤其涉及一种二次电池及其制备方法，以及包含其的电池模块、电池包和用电装置。
背景技术
近年来，随着锂离子二次电池的应用范围越来越广泛，锂离子电池广泛应用于水力、火力、风力和太阳能电站等储能电源系统，以及电动工具、电动自行车、电动摩托车、电动汽车、军事装备、航空航天等多个领域。由于锂离子电池取得了极大的发展，因此对其循环性能和安全性能等也提出了更高的要求。
在锂离子二次电池中，电池在经过多次充放电循环后，锂会在电极上析出，析出的锂可能生长成为锂枝晶。锂枝晶会刺破隔离膜，导致电芯热失控，从而缩短电池的循环寿命，甚至影响电池的安全。因此，需要抑制锂离子二次电池循环过程中锂枝晶的生长。
发明内容
本申请是鉴于上述课题而进行的，其目的在于，提供一种二次电池，所述二次电池在循环过程中的锂枝晶形成得到了抑制。
为了达到上述目的，本申请的第一方面提供了一种二次电池，其包含负极极片，所述负极极片包含负极集流体以及设置在负极集流体至少一个表面上的负极膜层，所述负极膜层中含有硝酸盐。
由此，本申请通过在电池的负极膜层中加入硝酸盐，能够有效地抑制锂离子二次电池中的锂枝晶生长。
在任意实施方式中，所述硝酸盐选自硝酸镁、硝酸铜、硝酸锌、硝酸钙、硝酸铝、硝酸银、硝酸锂、硝酸钾和硝酸钠中的一种或多种；可选地，所述硝酸盐选自硝酸镁、硝酸铜、硝酸锌、硝酸钙和硝酸铝 中的一种或多种；进一步可选地，所述硝酸盐选自硝酸镁、硝酸铜和硝酸锌中的一种或多种；再进一步可选地，所述硝酸盐为硝酸镁。
通过对硝酸盐种类的选择，能够进一步优化硝酸盐抑制锂枝晶生长的效果。
在任意实施方式中，基于负极膜层的总重量计，所述负极膜层中的硝酸盐含量为0.2重量％以上；可选地为0.2重量％-4.5重量％；进一步可选地为0.2重量％-1.5重量％。
通过对硝酸盐含量的选择，能够进一步优化硝酸盐抑制锂枝晶生长的效果。
在任意实施方式中，所述负极膜层包含负极活性材料，所述负极活性材料包括碳基负极活性材料和硅基负极活性材料中的至少一种。
在这样的二次电池中，可以更显著地抑制锂枝晶。
在任意实施方式中，所述二次电池包括电解液，所述电解液中也含有硝酸盐；可选地，基于电解液的总重量计，所述电解液中的硝酸盐含量为0.1重量％以上。
电解液中的硝酸盐能够起到抑制锂枝晶形成的作用。
本申请的第二方面还提供一种制备二次电池的方法，包括采用如下步骤制备负极极片：
将包含负极活性材料和硝酸盐的浆料涂覆到负极集流体的至少一个表面上。
由于在负极膜层中加入硝酸盐，因此能够有效地抑制锂离子二次电池中的锂枝晶生长。
在任意实施方式中，所述硝酸盐选自硝酸镁、硝酸铜、硝酸锌、硝酸钙、硝酸铝、硝酸银、硝酸锂、硝酸钾和硝酸钠中的一种或多种；可选地，所述硝酸盐选自硝酸镁、硝酸铜、硝酸锌、硝酸钙和硝酸铝中的一种或多种；进一步可选地，所述硝酸盐选自硝酸镁、硝酸铜和硝酸锌中的一种或多种；再进一步可选地，所述硝酸盐为硝酸镁。
通过对硝酸盐种类的选择，能够进一步优化硝酸盐抑制锂枝晶生长的效果。
在任意实施方式中，所述硝酸盐的含量为0.5重量％以上，可选地为0.5重量％-5重量％，进一步可选地为0.5重量％-2重量％，基于所述浆料的干重计。
通过控制加入所述浆料中的硝酸盐含量，能够获得适当的负极膜层和电解液中的硝酸盐含量。
在任意实施方式中，所述负极活性材料包括碳基负极活性材料和/或硅基负极活性材料。
在这样的二次电池中，可以更显著地抑制锂枝晶。
本申请的第三方面提供一种用电装置，包括选自本申请的第一方面的二次电池和通过本申请第二方面的制备二次电池的方法获得的二次电池中的至少一种。
附图说明
图1是推测的硝酸盐抑制锂枝晶的原理示意图。
图2是实施例和对比例的电池在循环后的析锂区域扫描电镜(SEM)表征图。
图3是对比例1(A)和实施例1(B)的析锂区域对应位置的隔离膜的CCD(电感耦合器件)局部放大图。
图4是本申请一实施方式的二次电池的示意图。
图5是图4所示的本申请一实施方式的二次电池的分解图。
图6是本申请一实施方式的电池模块的示意图。
图7是本申请一实施方式的电池包的示意图。
图8是图7所示的本申请一实施方式的电池包的分解图。
图9是本申请一实施方式的二次电池用作电源的用电装置的示意图。
附图标记说明：
1电池包；2上箱体；3下箱体；4电池模块；5二次电池；51壳体；52电极组件；53顶盖组件
具体实施方式
以下，适当地参照附图详细说明具体公开了本申请的二次电池、电池模块、电池包和电学装置的实施方式。但是会有省略不必要的详细说明的情况。例如，有省略对已众所周知的事项的详细说明、实际相同结构的重复说明的情况。这是为了避免以下的说明不必要地变得冗长，便于本领域技术人员的理解。此外，附图及以下说明是为了本领域技术人员充分理解本申请而提供的，并不旨在限定权利要求书所记载的主题。
本申请所公开的“范围”以下限和上限的形式来限定，给定范围是通过选定一个下限和一个上限进行限定的，选定的下限和上限限定了特别范围的边界。这种方式进行限定的范围可以是包括端值或不包括端值的，并且可以进行任意地组合，即任何下限可以与任何上限组合形成一个范围。例如，如果针对特定参数列出了60-120和80-110的范围，理解为60-110和80-120的范围也是预料到的。此外，如果列出的最小范围值1和2，和如果列出了最大范围值3，4和5，则下面的范围可全部预料到：1-3、1-4、1-5、2-3、2-4和2-5。在本申请中，除非有其他说明，数值范围“a-b”表示a到b之间的任意实数组合的缩略表示，其中a和b都是实数。例如数值范围“0-5”表示本文中已经全部列出了“0-5”之间的全部实数，“0-5”只是这些数值组合的缩略表示。另外，当表述某个参数为≥2的整数，则相当于公开了该参数为例如整数2、3、4、5、6、7、8、9、10、11、12等。
如果没有特别的说明，本申请的所有实施方式以及可选实施方式可以相互组合形成新的技术方案。
如果没有特别的说明，本申请的所有技术特征以及可选技术特征可以相互组合形成新的技术方案。
如果没有特别的说明，本申请的所有步骤可以顺序进行，也可以随机进行，优选是顺序进行的。例如，所述方法包括步骤(a)和(b)，表示所述方法可包括顺序进行的步骤(a)和(b)，也可以包括顺序进行的步骤(b)和(a)。例如，所述提到所述方法还可包括步骤(c)，表示步骤(c)可以任意顺序加入到所述方法，例如，所述方法可以包括步骤(a)、 (b)和(c)，也可包括步骤(a)、(c)和(b)，也可以包括步骤(c)、(a)和(b)等。
如果没有特别的说明，本申请所提到的“包括”和“包含”表示开放式，也可以是封闭式。例如，所述“包括”和“包含”可以表示还可以包括或包含没有列出的其他组分，也可以仅包括或包含列出的组分。
如果没有特别的说明，在本申请中，术语“或”是包括性的。举例来说，短语“A或B”表示“A，B，或A和B两者”。更具体地，以下任一条件均满足条件“A或B”：A为真(或存在)并且B为假(或不存在)；A为假(或不存在)而B为真(或存在)；或A和B都为真(或存在)。
本申请的发明人发现，在以碳基材料和/或硅基材料为负极活性材料的锂离子二次电池中，电池在经过多次充放电循环后，有明显的锂枝晶生长，且由于硝酸盐在电解液中的溶解度很有限，因此通过在电解液中添加硝酸盐并不能达到良好的抑制锂枝晶生长的效果。
需要开发新的方法来抑制锂离子二次电池中的锂枝晶生长。
本申请的一个实施方式中，本申请提出了一种二次电池，其包含负极极片，所述负极极片包含负极集流体以及设置在负极集流体至少一个表面上的负极膜层，所述负极膜层中含有硝酸盐。
虽然机理尚不明确，但本申请人意外地发现：本申请通过在电池的负极膜层中加入硝酸盐，能够有效地抑制锂离子二次电池中的锂枝晶生长。电池在多次循环后，即使在电极上发生析锂，锂也基本呈球形状态，不会生长为能够刺破隔离膜的枝晶。推测本发明能有效抑制锂枝晶生长的原因之一是负极中包含的硝酸盐能够在电池循环过程中逐渐扩散到电解液中，使电解液中含有足量的硝酸盐(例如参见图1所示的原理图)。并且，当析锂发生时，由于锂的强还原性，硝酸盐中的金属元素被还原与锂形成合金，降低了扩散能垒，从而抑制了锂枝晶的形成。本申请中，虽然硝酸盐中的金属元素被还原，但SEI层的厚度仍保持在低于500nm，从而不会明显增加阻抗。
在一些实施方式中，所述硝酸盐选自硝酸镁、硝酸铜、硝酸锌、硝酸钙、硝酸铝、硝酸银、硝酸锂、硝酸钾和硝酸钠中的一种或多种；可选地，所述硝酸盐选自硝酸镁、硝酸铜、硝酸锌、硝酸钙和硝酸铝中的一种或多种；进一步可选地，所述硝酸盐选自硝酸镁、硝酸铜和硝酸锌中的一种或多种；再进一步可选地，所述硝酸盐为硝酸镁。
通过对硝酸盐种类的选择，能够进一步优化硝酸盐抑制锂枝晶生长的效果。
在一些实施方式中，基于负极膜层的总重量计，所述负极膜层中的硝酸盐含量为0.2重量％以上，例如，硝酸盐含量可为0.3重量％、0.4重量％、0.5重量％、0.6重量％、1.5重量％、3.5重量％或处于上述数值中的任意二者所形成的范围内；可选地，硝酸盐含量为0.2重量％-4.5重量％的硝酸盐，进一步可选地为0.2重量％-1.5重量％。
通过对硝酸盐含量的选择，能够进一步优化硝酸盐抑制锂枝晶生长的效果。如果含量低于0.2重量％，某些情况下可能硝酸盐消耗较快，不利于电池长期循环。如果含量高于4.5重量％，则较多地占据了负极膜层的重量，不利于提高电池的能量密度。过高的硝酸盐含量也有可能导致阳极脱膜。
在一些实施方式中，所述负极膜层包含负极活性材料，所述负极活性材料包括碳基负极活性材料和硅基负极活性材料中的至少一种。
在这样的二次电池中，可以更显著地抑制锂枝晶。
可选地，所述负极活性材料包括碳基负极活性材料，可选地，所述碳基负极活性材料包含石墨、中间相炭微球、软碳和硬碳中的至少一种。
对所述碳基负极活性材料没有特别限定，可使用本领域中常规的碳基负极活性材料。例如，可使用Dv50为2-20μm的碳基负极活性材料。可选地，硬碳的Dv50范围为2-10μm，石墨的Dv50范围为10-20μm，软碳的Dv50范围为5-20μm，中间相炭微球的Dv50范围为10-20μm。
在一些实施方式中，所述二次电池包括电解液，所述电解液中也 含有硝酸盐；可选地，基于电解液的总重量计，所述电解液中的硝酸盐含量为0.1重量％以上。
电解液中的硝酸盐能够起到抑制锂枝晶形成的作用。
在一些实施方式中，所述二次电池为锂离子二次电池。
本申请还提供一种制备二次电池的方法，包括采用如下步骤制备负极极片：
将包含负极活性材料和硝酸盐的浆料涂覆到负极集流体的至少一个表面上。
如前所述，由于通过上述方法制备的二次电池在负极膜层中加入硝酸盐，因此能够有效地抑制锂离子二次电池中的锂枝晶生长。并且，将硝酸盐加入浆料中还有利于通过随后的干燥极片的操作而去除硝酸盐通常含有的结晶水。
在一些实施方式中，所述硝酸盐的含量为0.5重量％以上，例如，所述硝酸盐的含量为0.7重量％、1重量％、2重量％、4重量％、10重量％或处于上述数值中的任意二者所形成的范围内，基于所述浆料的干重计。可选地，所述硝酸盐的含量为0.5重量％-5重量％，进一步可选地为0.5重量％-2重量％，基于所述浆料的干重计。
通过控制加入所述浆料中的硝酸盐含量，能够获得适当的负极膜层和电解液中的硝酸盐含量。
上述关于二次电池所限定的特征和定义同样适用于所述制备方法。并且，制备二次电池的方法的其他步骤可采用本领域中常规的制备步骤。
另外，以下适当参照附图对本申请的二次电池的其他方面、电池模块、电池包和用电装置进行说明。
二次电池包括正极极片、负极极片、电解液和隔离膜。在电池充放电过程中，活性离子在正极极片和负极极片之间往返嵌入和脱出。电解液在正极极片和负极极片之间起到传导离子的作用。隔离膜设置在正极极片和负极极片之间，主要起到防止正负极短路的作用，同时可以使离子通过。
[正极极片]
正极极片包括正极集流体以及设置在正极集流体至少一个表面的正极膜层，所述正极膜层包括正极活性材料。
作为示例，正极集流体具有在其自身厚度方向相对的两个表面，正极膜层设置在正极集流体相对的两个表面的其中任意一者或两者上。
在一些实施方式中，所述正极集流体可采用金属箔片或复合集流体。例如，作为金属箔片，可采用铝箔。复合集流体可包括高分子材料基层和形成于高分子材料基层至少一个表面上的金属层。复合集流体可通过将金属材料(铝、铝合金、镍、镍合金、钛、钛合金、银及银合金等)形成在高分子材料基材(如聚丙烯(PP)、聚对苯二甲酸乙二醇酯(PET)、聚对苯二甲酸丁二醇酯(PBT)、聚苯乙烯(PS)、聚乙烯(PE)等的基材)上而形成。
在一些实施方式中，正极活性材料可采用本领域公知的用于电池的正极活性材料。作为示例，正极活性材料可包括以下材料中的至少一种：橄榄石结构的含锂磷酸盐、锂过渡金属氧化物及其各自的改性化合物。但本申请并不限定于这些材料，还可以使用其他可被用作电池正极活性材料的传统材料。这些正极活性材料可以仅单独使用一种，也可以将两种以上组合使用。其中，锂过渡金属氧化物的示例可包括但不限于锂钴氧化物(如LiCoO 2)、锂镍氧化物(如LiNiO 2)、锂锰氧化物(如LiMnO 2、LiMn 2O 4)、锂镍钴氧化物、锂锰钴氧化物、锂镍锰氧化物、锂镍钴锰氧化物(如LiNi 1/3Co 1/3Mn 1/3O 2(也可以简称为NCM 333)、LiNi 0.5Co 0.2Mn 0.3O 2(也可以简称为NCM 523)、LiNi 0.5Co 0.25Mn 0.25O 2(也可以简称为NCM 211)、LiNi 0.6Co 0.2Mn 0.2O 2(也可以简称为NCM 622)、LiNi 0.8Co 0.1Mn 0.1O 2(也可以简称为NCM 811)、锂镍钴铝氧化物(如LiNi 0.85Co 0.15Al 0.05O 2)及其改性化合物等中的至少一种。橄榄石结构的含锂磷酸盐的示例可包括但不限于磷酸铁锂(如LiFePO 4(也可以简称为LFP))、磷酸铁锂与碳的复合材料、磷酸锰锂(如LiMnPO 4)、磷酸锰锂与碳的复合材料、磷酸锰铁锂、磷 酸锰铁锂与碳的复合材料中的至少一种。
在一些实施方式中，正极膜层还可选地包括粘结剂。作为示例，所述粘结剂可以包括聚偏氟乙烯(PVDF)、聚四氟乙烯(PTFE)、偏氟乙烯-四氟乙烯-丙烯三元共聚物、偏氟乙烯-六氟丙烯-四氟乙烯三元共聚物、四氟乙烯-六氟丙烯共聚物及含氟丙烯酸酯树脂中的至少一种。
在一些实施方式中，正极膜层还可选地包括导电剂。作为示例，所述导电剂可以包括超导碳、乙炔黑、炭黑、科琴黑、碳点、碳纳米管、石墨烯及碳纳米纤维中的至少一种。
在一些实施方式中，可以通过以下方式制备正极极片：将上述用于制备正极极片的组分，例如正极活性材料、导电剂、粘结剂和任意其他的组分分散于溶剂(例如N-甲基吡咯烷酮)中，形成正极浆料；将正极浆料涂覆在正极集流体上，经烘干、冷压等工序后，即可得到正极极片。
[负极极片]
负极极片包括负极集流体以及设置在负极集流体至少一个表面上的负极膜层，所述负极膜层包括负极活性材料。
作为示例，负极集流体具有在其自身厚度方向相对的两个表面，负极膜层设置在负极集流体相对的两个表面中的任意一者或两者上。
在一些实施方式中，所述负极集流体可采用金属箔片或复合集流体。例如，作为金属箔片，可以采用铜箔。复合集流体可包括高分子材料基层和形成于高分子材料基材至少一个表面上的金属层。复合集流体可通过将金属材料(铜、铜合金、镍、镍合金、钛、钛合金、银及银合金等)形成在高分子材料基材(如聚丙烯(PP)、聚对苯二甲酸乙二醇酯(PET)、聚对苯二甲酸丁二醇酯(PBT)、聚苯乙烯(PS)、聚乙烯(PE)等的基材)上而形成。
负极活性材料可为碳基负极活性材料和/或硅基负极活性材料。作为示例，负极活性材料可包括以下材料中的至少一种：人造石墨、天然石墨、中间相炭微球、软炭、硬炭、硅基材料等。所述硅基材料 可选自单质硅、硅氧化合物、硅碳复合物、硅氮复合物以及硅合金中的至少一种。但本申请并不限定于这些材料。这些负极活性材料可以仅单独使用一种，也可以将两种以上组合使用。
在一些实施方式中，负极膜层还可选地包括粘结剂。所述粘结剂可选自丁苯橡胶(SBR)、聚丙烯酸(PAA)、聚丙烯酸钠(PAAS)、聚丙烯酰胺(PAM)、聚乙烯醇(PVA)、海藻酸钠(SA)、聚甲基丙烯酸(PMAA)及羧甲基壳聚糖(CMCS)中的至少一种。
在一些实施方式中，负极膜层还可选地包括导电剂。导电剂可选自超导碳、乙炔黑、炭黑、科琴黑、碳点、碳纳米管、石墨烯及碳纳米纤维中的至少一种。
在一些实施方式中，负极膜层还可选地包括其他助剂，例如增稠剂(如羧甲基纤维素钠(CMC-Na))等。
在一些实施方式中，可以通过以下方式制备负极极片：将上述用于制备负极极片的组分，例如负极活性材料、导电剂、硝酸盐、粘结剂和任意其他组分分散于溶剂(例如去离子水)中，形成负极浆料；将负极浆料涂覆在负极集流体上，经烘干、冷压等工序后，即可得到负极极片。
[电解液]
电解液在正极极片和负极极片之间起到传导离子的作用。本申请对电解液的种类没有具体的限制，可根据需求进行选择。所述电解液包括电解质盐和溶剂。
在一些实施方式中，电解质盐可选自六氟磷酸锂、四氟硼酸锂、高氯酸锂、六氟砷酸锂、双氟磺酰亚胺锂、双三氟甲磺酰亚胺锂、三氟甲磺酸锂、二氟磷酸锂、二氟草酸硼酸锂、二草酸硼酸锂、二氟二草酸磷酸锂及四氟草酸磷酸锂中的至少一种。
在一些实施方式中，溶剂可选自碳酸亚乙酯(EC)、碳酸亚丙酯、碳酸甲乙酯、碳酸二乙酯(DEC)、碳酸二甲酯、碳酸二丙酯、碳酸甲丙酯、碳酸乙丙酯、碳酸亚丁酯、氟代碳酸亚乙酯、甲酸甲酯、乙酸甲酯、乙酸乙酯、乙酸丙酯、丙酸甲酯、丙酸乙酯、丙酸丙酯、丁 酸甲酯、丁酸乙酯、1，4-丁内酯、环丁砜、二甲砜、甲乙砜及二乙砜中的至少一种。
在一些实施方式中，所述电解液还可选地包括添加剂。例如添加剂可以包括负极成膜添加剂、正极成膜添加剂，还可以包括能够改善电池某些性能的添加剂，例如改善电池过充性能的添加剂、改善电池高温或低温性能的添加剂等。通过使用添加剂，还可以调整硝酸盐在电解液中的溶解度，从而改变电解液中的硝酸盐含量。
[隔离膜]
在一些实施方式中，二次电池中还包括隔离膜。本申请对隔离膜的种类没有特别的限制，可以选用任意公知的具有良好的化学稳定性和机械稳定性的多孔结构隔离膜。
在一些实施方式中，隔离膜的材质可选自玻璃纤维、无纺布、聚乙烯、聚丙烯及聚偏二氟乙烯中的至少一种。隔离膜可以是单层薄膜，也可以是多层复合薄膜，没有特别限制。在隔离膜为多层复合薄膜时，各层的材料可以相同或不同，没有特别限制。
在一些实施方式中，正极极片、负极极片和隔离膜可通过卷绕工艺或叠片工艺制成电极组件。
在一些实施方式中，二次电池可包括外包装。该外包装可用于封装上述电极组件及电解质。
在一些实施方式中，二次电池的外包装可以是硬壳，例如硬塑料壳、铝壳、钢壳等。二次电池的外包装也可以是软包，例如袋式软包。软包的材质可以是塑料，作为塑料，可列举出聚丙烯、聚对苯二甲酸丁二醇酯以及聚丁二酸丁二醇酯等。
本申请对二次电池的形状没有特别的限制，其可以是圆柱形、方形或其他任意的形状。例如，图4是作为一个示例的方形结构的二次电池5。
在一些实施方式中，参照图5，外包装可包括壳体51和盖板53。其中，壳体51可包括底板和连接于底板上的侧板，底板和侧板围合形成容纳腔。壳体51具有与容纳腔连通的开口，盖板53能够盖设于 所述开口，以封闭所述容纳腔。正极极片、负极极片和隔离膜可经卷绕工艺或叠片工艺形成电极组件52。电极组件52封装于所述容纳腔内。电解液浸润于电极组件52中。二次电池5所含电极组件52的数量可以为一个或多个，本领域技术人员可根据具体实际需求进行选择。
在一些实施方式中，二次电池可以组装成电池模块，电池模块所含二次电池的数量可以为一个或多个，具体数量本领域技术人员可根据电池模块的应用和容量进行选择。
图6是作为一个示例的电池模块4。参照图6，在电池模块4中，多个二次电池5可以是沿电池模块4的长度方向依次排列设置。当然，也可以按照其他任意的方式进行排布。进一步可以通过紧固件将该多个二次电池5进行固定。
可选地，电池模块4还可以包括具有容纳空间的外壳，多个二次电池5容纳于该容纳空间。
在一些实施方式中，上述电池模块还可以组装成电池包，电池包所含电池模块的数量可以为一个或多个，具体数量本领域技术人员可根据电池包的应用和容量进行选择。
图7和图8是作为一个示例的电池包1。参照图7和图8，在电池包1中可以包括电池箱和设置于电池箱中的多个电池模块4。电池箱包括上箱体2和下箱体3，上箱体2能够盖设于下箱体3，并形成用于容纳电池模块4的封闭空间。多个电池模块4可以按照任意的方式排布于电池箱中。
另外，本申请还提供一种用电装置，所述用电装置包括本申请提供的二次电池、电池模块、或电池包中的至少一种。所述二次电池、电池模块、或电池包可以用作所述用电装置的电源，也可以用作所述用电装置的能量存储单元。所述用电装置可以包括移动设备(例如手机、笔记本电脑等)、电动车辆(例如纯电动车、混合动力电动车、插电式混合动力电动车、电动自行车、电动踏板车、电动高尔夫球车、电动卡车等)、电气列车、船舶及卫星、储能系统等，但不限于此。
作为所述用电装置，可以根据其使用需求来选择二次电池、电池 模块或电池包。
图9是作为一个示例的用电装置。该用电装置为纯电动车、混合动力电动车、或插电式混合动力电动车等。为了满足该用电装置对二次电池的高功率和高能量密度的需求，可以采用电池包或电池模块。
作为另一个示例的装置可以是手机、平板电脑、笔记本电脑等。该装置通常要求轻薄化，可以采用二次电池作为电源。
实施例
以下，说明本申请的实施例。下面描述的实施例是示例性的，仅用于解释本申请，而不能理解为对本申请的限制。实施例中未注明具体技术或条件的，按照本领域内的文献所描述的技术或条件或者按照产品说明书进行。所用试剂或仪器未注明生产厂商者，均为可以通过市购获得的常规产品。
实施例1
将人造石墨、硝酸镁、导电炭黑、羧甲基纤维素钠(CMC-Na)和高分子聚合物SBR(丁苯橡胶)以重量比96∶1∶1∶1∶1加到去离子水中搅拌成均匀的浆料，将浆料涂覆在铜箔上并烘干即得到负极极片，其单面涂覆量为0.15g/1540.25mm 2。
将LiNi 0.8Co 0.1Mn 0.1O 2(NCM 811)、导电炭黑、聚偏氟乙烯粘结剂(PVDF)以重量比97∶1∶2加到N-甲基吡咯烷酮(NMP)中搅拌成均匀的浆料，将浆料涂覆在铝箔上并烘干即得到正极极片，其单面涂覆量为0.28g/1540.25mm 2。
碳酸亚乙酯(EC)、碳酸二乙酯(DEC)按体积比1∶1混合，然后将LiPF 6均匀溶解在上述溶液中，得到电解液。该电解液中，LiPF 6的浓度为1mol/L。
以聚乙烯(PE)为隔离膜。
将上述正极极片、隔离膜、负极极片按顺序叠好，使隔离膜处于正、负极极片之间，加入上述电解液组装成叠片电池。
实施例2
除在负极制备中将硝酸镁的添加量增加到2重量％，石墨降为95 重量％外，其他步骤与实施例1相同。
实施例3
除在负极制备中将硝酸镁的添加量增加到5重量％，石墨降为92重量％外，其他步骤与实施例1相同。
实施例4
除在负极制备中将硝酸镁的添加量增加到4重量％，石墨降为93重量％外，其他步骤与实施例1相同。
实施例5
除将硝酸镁的添加量减为0.7重量％，石墨增加到96.3重量％外，其他步骤与实施例1相同。
实施例6
除将硝酸镁的添加量增加到10重量％，石墨降为87重量％外，其他步骤与实施例1相同。
实施例7
除将硝酸镁换为硝酸铜外，其他步骤与实施例1相同。
实施例8
除将硝酸镁换为硝酸锌外，其他步骤与实施例1相同。
实施例9
除将硝酸镁换为硝酸钙外，其他步骤与实施例1相同。
实施例10
除将硝酸镁换为硝酸铝外，其他步骤与实施例1相同。
实施例11
除将石墨换为硅基材料，负极单面涂覆量由0.15g/1540.25mm 2减少至0.05g/1540.25mm 2外，其他步骤与实施例1相同。
实施例12
除将石墨换为硬碳，负极单面涂覆量由0.15g/1540.25mm 2减少至0.135g/1540.25mm 2外，其他步骤与实施例1相同。
实施例13
除将将石墨换为中间相炭微球，负极单面涂覆量由0.15g/1540.25mm 2减少至0.13g/1540.25mm 2外，其他步骤与实施例1相同。
对比例1
对比例1的制备步骤与实施例1类似，不同点在于：负极不添加硝酸镁，石墨增加到97重量％。
对比例2
对比例1的制备步骤与实施例1类似，不同点在于：负极不添加硝酸镁，石墨增加到97重量％；电解液中添加1.2重量％的硝酸镁。
【电池测试方法】
1.析锂形貌
使用2C直充流程，即，将锂离子电池在25℃下以2C的恒定电流充电至4.25V，之后以4.25V恒压充电至电流降到0.05C，再以1C的恒定电流放电至2.8V，以此进行循环，使负极表面析锂。分别将上述制备的电池循环600圈和循环1500圈。然后将满充状态下的电池拆解，通过SEM观察析锂的形貌以及通过CCD观察隔离膜情况。其中，通过目测SEM图来对析锂形貌进行分级，“平坦”表示极片表面几乎看不到凸起，“稍有凸起”表示极片表面有可见的但高度较低的凸起，“明显凸起”表示极片表面有高度较高的凸起，“锂枝晶”表示极片表面出现了枝晶形态的析锂。
图2显示了实施例和对比例的电池在循环后的析锂区域扫描电镜(SEM)图。其中(a)图为实施例10(A)、实施例8(B)和实施例1(C)的电池在经过1500次循环后的析锂区域扫描电镜(SEM)图。图中虚线代表极片表面的水平面，可以看出A有明显凸起，B稍 有凸起，C平坦，基本没有凸起。三者均近似球形形貌，即，不形成枝晶。图2的(b)图为对比例1(A)和实施例1(B)在循环600圈后的析锂区域扫描电镜(SEM)图，使用了较高的放大倍数。由图中可以看出，实施例1的析锂形貌为球形，而对比例1的析锂形貌为枝晶。
图3显示了对比例1(A)和实施例1(B)在循环600圈后的析锂区域对应位置的隔离膜的CCD局部放大图。由图中可以看出，对比例1的隔离膜有析锂刺破孔，而实施例1的隔离膜保持完整。
2.负极膜层中的硝酸盐含量
负极中的硝酸盐含量通过ICP测试对应的金属含量确认。具体操作方式为：将所制备的电池经过化成后拆解，负极极片取一定面积，称取重量，然后用浓硝酸消解，随后将溶液稀释后，通过ICP测试稀释后溶液中的金属重量，根据测试的金属重量并根据负极膜层重量(即，称取的极片重量减去基材重量)计算负极膜层中的硝酸盐含量。
3.电解液中的硝酸盐含量
通过ICP测定电解液中的硝酸盐的浓度。所制备的电池经过化成后，拆开电池，将电解液稀释，通过ICP测试其中的硝酸盐金属离子的浓度从而换算出硝酸盐浓度。
4.SEI层厚度
SEI层厚度通过氩离子抛光技术结合SEM来进行离子抛光断面形貌分析而确定，由于SEM图中负极膜层的颜色明显比SEI膜的颜色更深，因此可通过颜色差异确定二者之间的分界线，由此可量取负极膜层表面SEI层的厚度。
Figure PCTCN2022114750-appb-000001
Figure PCTCN2022114750-appb-000002
根据上述结果可知，实施例1-13由于在负极膜层中均加入了硝酸盐，因此电池在经过600圈循环后均未形成枝晶，并且即使经过1500圈循环后隔膜也没有被刺破。相比而言，对比例1的电池中完全未加入硝酸盐，电池经过600圈循环后即形成了刺破隔膜的枝晶。对比例2仅在电解液中加入硝酸盐，虽然电池经过600圈循环后隔膜尚未刺破，但经过1500圈循环后仍生成了将隔膜刺破的枝晶。
需要说明的是，本申请不限定于上述实施方式。上述实施方式仅为示例，在本申请的技术方案范围内具有与技术思想实质相同的构成、发挥相同作用效果的实施方式均包含在本申请的技术范围内。此外，在不脱离本申请主旨的范围内，对实施方式施加本领域技术人员能够想到的各种变形、将实施方式中的一部分构成要素加以组合而构筑的其它方式也包含在本申请的范围内。

Claims (10)

  1. 一种二次电池，其包含负极极片，所述负极极片包含负极集流体以及设置在负极集流体至少一个表面上的负极膜层，所述负极膜层中含有硝酸盐。
  2. 根据权利要求1所述的二次电池，其中，所述硝酸盐选自硝酸镁、硝酸铜、硝酸锌、硝酸钙、硝酸铝、硝酸银、硝酸锂、硝酸钾和硝酸钠中的一种或多种；可选地，所述硝酸盐选自硝酸镁、硝酸铜、硝酸锌、硝酸钙和硝酸铝中的一种或多种；进一步可选地，所述硝酸盐选自硝酸镁、硝酸铜和硝酸锌中的一种或多种；再进一步可选地，所述硝酸盐为硝酸镁。
  3. 根据权利要求1或2所述的二次电池，其中，基于负极膜层的总重量计，所述负极膜层中的硝酸盐含量为0.2重量％以上；可选地为0.2重量％-4.5重量％；进一步可选地为0.2重量％-1.5重量％。
  4. 根据权利要求1-3中任一项所述的二次电池，其中，所述负极膜层包含负极活性材料，所述负极活性材料包括碳基负极活性材料和硅基负极活性材料中的至少一种。
  5. 根据权利要求1-4中任一项所述的二次电池，其中，所述二次电池包括电解液，所述电解液中也含有硝酸盐；可选地，基于电解液的总重量计，所述电解液中的硝酸盐含量为0.1重量％以上。
  6. 一种制备二次电池的方法，包括采用如下步骤制备负极极片：
    将包含负极活性材料和硝酸盐的浆料涂覆到负极集流体的至少一个表面上。
  7. 根据权利要求6所述的制备二次电池的方法，其中，所述硝酸盐选自硝酸镁、硝酸铜、硝酸锌、硝酸钙、硝酸铝、硝酸银、硝酸锂、硝酸钾和硝酸钠中的一种或多种；可选地，所述硝酸盐选自硝酸镁、硝酸铜、硝酸锌、硝酸钙和硝酸铝中的一种或多种；进一步可选地，所述硝酸盐选自硝酸镁、硝酸铜和硝酸锌中的一种或多种；再进一步可选地，所述硝酸盐为硝酸镁。
  8. 根据权利要求6或7所述的制备二次电池的方法，其中，所述硝酸盐的含量为0.5重量％以上，可选地为0.5重量％-5重量％，进一步可选地为0.5重量％-2重量％，基于所述浆料的干重计。
  9. 根据权利要求6至8中任一项所述的制备二次电池的方法，其中，所述负极活性材料包括碳基负极活性材料和/或硅基负极活性材料。
  10. 一种用电装置，其特征在于，包括选自权利要求1-5中任一项所述的二次电池和通过权利要求6-9中任一项所述的制备二次电池的方法获得的二次电池中的至少一种。
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Citations (4)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JP2005197175A (ja) * 2004-01-09 2005-07-21 Sony Corp 正極、負極、電解質および電池
JP2018098027A (ja) * 2016-12-13 2018-06-21 オートモーティブエナジーサプライ株式会社 リチウムイオン二次電池
CN110838575A (zh) * 2018-08-17 2020-02-25 中国科学院物理研究所 一种用于提高锂离子储能器件倍率性能的负极及其用途
CN112563465A (zh) * 2019-09-26 2021-03-26 广州汽车集团股份有限公司 负极浆料、负极片、锂离子软包电芯、锂离子电池包及其应用

Patent Citations (4)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JP2005197175A (ja) * 2004-01-09 2005-07-21 Sony Corp 正極、負極、電解質および電池
JP2018098027A (ja) * 2016-12-13 2018-06-21 オートモーティブエナジーサプライ株式会社 リチウムイオン二次電池
CN110838575A (zh) * 2018-08-17 2020-02-25 中国科学院物理研究所 一种用于提高锂离子储能器件倍率性能的负极及其用途
CN112563465A (zh) * 2019-09-26 2021-03-26 广州汽车集团股份有限公司 负极浆料、负极片、锂离子软包电芯、锂离子电池包及其应用

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