CN115411226A - Positive pole piece and battery - Google Patents
Positive pole piece and battery Download PDFInfo
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- CN115411226A CN115411226A CN202211087845.XA CN202211087845A CN115411226A CN 115411226 A CN115411226 A CN 115411226A CN 202211087845 A CN202211087845 A CN 202211087845A CN 115411226 A CN115411226 A CN 115411226A
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- 239000002210 silicon-based material Substances 0.000 claims abstract description 33
- 239000007774 positive electrode material Substances 0.000 claims abstract description 26
- 239000003575 carbonaceous material Substances 0.000 claims abstract description 23
- 239000010410 layer Substances 0.000 claims description 38
- -1 polyethylene Polymers 0.000 claims description 33
- 239000007789 gas Substances 0.000 claims description 25
- 239000003792 electrolyte Substances 0.000 claims description 18
- 238000000576 coating method Methods 0.000 claims description 17
- 229910052744 lithium Inorganic materials 0.000 claims description 16
- 239000011248 coating agent Substances 0.000 claims description 15
- OKTJSMMVPCPJKN-UHFFFAOYSA-N Carbon Chemical compound [C] OKTJSMMVPCPJKN-UHFFFAOYSA-N 0.000 claims description 14
- 239000004698 Polyethylene Substances 0.000 claims description 13
- 229920000573 polyethylene Polymers 0.000 claims description 13
- 229920000642 polymer Polymers 0.000 claims description 13
- SBLRHMKNNHXPHG-UHFFFAOYSA-N 4-fluoro-1,3-dioxolan-2-one Chemical compound FC1COC(=O)O1 SBLRHMKNNHXPHG-UHFFFAOYSA-N 0.000 claims description 12
- 239000004743 Polypropylene Substances 0.000 claims description 12
- 229920001155 polypropylene Polymers 0.000 claims description 12
- 239000000758 substrate Substances 0.000 claims description 12
- OBNDGIHQAIXEAO-UHFFFAOYSA-N [O].[Si] Chemical compound [O].[Si] OBNDGIHQAIXEAO-UHFFFAOYSA-N 0.000 claims description 10
- 229910052751 metal Inorganic materials 0.000 claims description 10
- 239000002184 metal Substances 0.000 claims description 9
- OIFBSDVPJOWBCH-UHFFFAOYSA-N Diethyl carbonate Chemical compound CCOC(=O)OCC OIFBSDVPJOWBCH-UHFFFAOYSA-N 0.000 claims description 8
- KMTRUDSVKNLOMY-UHFFFAOYSA-N Ethylene carbonate Chemical compound O=C1OCCO1 KMTRUDSVKNLOMY-UHFFFAOYSA-N 0.000 claims description 8
- JBTWLSYIZRCDFO-UHFFFAOYSA-N ethyl methyl carbonate Chemical compound CCOC(=O)OC JBTWLSYIZRCDFO-UHFFFAOYSA-N 0.000 claims description 8
- 239000000463 material Substances 0.000 claims description 7
- 229910021383 artificial graphite Inorganic materials 0.000 claims description 6
- 239000011247 coating layer Substances 0.000 claims description 6
- 239000002131 composite material Substances 0.000 claims description 6
- 239000002245 particle Substances 0.000 claims description 6
- 239000013078 crystal Substances 0.000 claims description 5
- 239000007773 negative electrode material Substances 0.000 claims description 5
- 239000000178 monomer Substances 0.000 claims description 4
- 229920003229 poly(methyl methacrylate) Polymers 0.000 claims description 4
- 239000004926 polymethyl methacrylate Substances 0.000 claims description 4
- 229920003171 Poly (ethylene oxide) Polymers 0.000 claims description 3
- 229920001328 Polyvinylidene chloride Polymers 0.000 claims description 3
- 229910021385 hard carbon Inorganic materials 0.000 claims description 3
- 239000002931 mesocarbon microbead Substances 0.000 claims description 3
- 239000005543 nano-size silicon particle Substances 0.000 claims description 3
- 229910021382 natural graphite Inorganic materials 0.000 claims description 3
- 229920002239 polyacrylonitrile Polymers 0.000 claims description 3
- 239000011118 polyvinyl acetate Substances 0.000 claims description 3
- 229920002689 polyvinyl acetate Polymers 0.000 claims description 3
- 239000004800 polyvinyl chloride Substances 0.000 claims description 3
- 229920000915 polyvinyl chloride Polymers 0.000 claims description 3
- 239000005033 polyvinylidene chloride Substances 0.000 claims description 3
- 239000002153 silicon-carbon composite material Substances 0.000 claims description 3
- 150000002927 oxygen compounds Chemical class 0.000 claims description 2
- XUIMIQQOPSSXEZ-UHFFFAOYSA-N Silicon Chemical compound [Si] XUIMIQQOPSSXEZ-UHFFFAOYSA-N 0.000 abstract description 11
- 239000010703 silicon Substances 0.000 abstract description 11
- 229910052710 silicon Inorganic materials 0.000 abstract description 11
- 150000001875 compounds Chemical class 0.000 abstract description 3
- 229910021450 lithium metal oxide Inorganic materials 0.000 abstract description 3
- 230000002349 favourable effect Effects 0.000 abstract description 2
- 230000000052 comparative effect Effects 0.000 description 15
- WHXSMMKQMYFTQS-UHFFFAOYSA-N Lithium Chemical compound [Li] WHXSMMKQMYFTQS-UHFFFAOYSA-N 0.000 description 11
- 239000011230 binding agent Substances 0.000 description 8
- HBBGRARXTFLTSG-UHFFFAOYSA-N Lithium ion Chemical compound [Li+] HBBGRARXTFLTSG-UHFFFAOYSA-N 0.000 description 7
- 230000008859 change Effects 0.000 description 7
- 239000011267 electrode slurry Substances 0.000 description 7
- 229910001416 lithium ion Inorganic materials 0.000 description 7
- 238000000034 method Methods 0.000 description 7
- 239000006258 conductive agent Substances 0.000 description 6
- 238000001035 drying Methods 0.000 description 6
- 229910002804 graphite Inorganic materials 0.000 description 6
- 239000010439 graphite Substances 0.000 description 6
- SECXISVLQFMRJM-UHFFFAOYSA-N N-Methylpyrrolidone Chemical compound CN1CCCC1=O SECXISVLQFMRJM-UHFFFAOYSA-N 0.000 description 5
- 238000007600 charging Methods 0.000 description 5
- 238000005056 compaction Methods 0.000 description 5
- 229910044991 metal oxide Inorganic materials 0.000 description 5
- 150000004706 metal oxides Chemical class 0.000 description 5
- 230000008569 process Effects 0.000 description 5
- 239000010405 anode material Substances 0.000 description 4
- VNWKTOKETHGBQD-UHFFFAOYSA-N methane Chemical compound C VNWKTOKETHGBQD-UHFFFAOYSA-N 0.000 description 4
- 238000002156 mixing Methods 0.000 description 4
- 238000003825 pressing Methods 0.000 description 4
- 239000002904 solvent Substances 0.000 description 4
- 239000002033 PVDF binder Substances 0.000 description 3
- VYPSYNLAJGMNEJ-UHFFFAOYSA-N Silicium dioxide Chemical compound O=[Si]=O VYPSYNLAJGMNEJ-UHFFFAOYSA-N 0.000 description 3
- 239000006182 cathode active material Substances 0.000 description 3
- 238000007599 discharging Methods 0.000 description 3
- 230000000694 effects Effects 0.000 description 3
- 229920002981 polyvinylidene fluoride Polymers 0.000 description 3
- 229910052814 silicon oxide Inorganic materials 0.000 description 3
- RYGMFSIKBFXOCR-UHFFFAOYSA-N Copper Chemical compound [Cu] RYGMFSIKBFXOCR-UHFFFAOYSA-N 0.000 description 2
- 229910052782 aluminium Inorganic materials 0.000 description 2
- XAGFODPZIPBFFR-UHFFFAOYSA-N aluminium Chemical compound [Al] XAGFODPZIPBFFR-UHFFFAOYSA-N 0.000 description 2
- 230000009286 beneficial effect Effects 0.000 description 2
- 229910052799 carbon Inorganic materials 0.000 description 2
- 229910021393 carbon nanotube Inorganic materials 0.000 description 2
- 239000002041 carbon nanotube Substances 0.000 description 2
- 239000011889 copper foil Substances 0.000 description 2
- 238000005336 cracking Methods 0.000 description 2
- 230000006866 deterioration Effects 0.000 description 2
- 230000007613 environmental effect Effects 0.000 description 2
- 239000011888 foil Substances 0.000 description 2
- 238000002955 isolation Methods 0.000 description 2
- 239000012528 membrane Substances 0.000 description 2
- 230000004048 modification Effects 0.000 description 2
- 238000012986 modification Methods 0.000 description 2
- 238000003756 stirring Methods 0.000 description 2
- RXBBZJPEEIUBJG-UHFFFAOYSA-N [O].[Si].[Li] Chemical compound [O].[Si].[Li] RXBBZJPEEIUBJG-UHFFFAOYSA-N 0.000 description 1
- 238000010521 absorption reaction Methods 0.000 description 1
- 239000011149 active material Substances 0.000 description 1
- 230000004888 barrier function Effects 0.000 description 1
- 239000006229 carbon black Substances 0.000 description 1
- 239000002134 carbon nanofiber Substances 0.000 description 1
- 239000003153 chemical reaction reagent Substances 0.000 description 1
- 238000010280 constant potential charging Methods 0.000 description 1
- 238000010277 constant-current charging Methods 0.000 description 1
- 230000001351 cycling effect Effects 0.000 description 1
- 238000009831 deintercalation Methods 0.000 description 1
- 239000008367 deionised water Substances 0.000 description 1
- 229910021641 deionized water Inorganic materials 0.000 description 1
- 229910021389 graphene Inorganic materials 0.000 description 1
- 230000006872 improvement Effects 0.000 description 1
- 239000007788 liquid Substances 0.000 description 1
- 230000014759 maintenance of location Effects 0.000 description 1
- 238000004806 packaging method and process Methods 0.000 description 1
- 238000007086 side reaction Methods 0.000 description 1
- 239000002002 slurry Substances 0.000 description 1
- 239000007784 solid electrolyte Substances 0.000 description 1
- 229920003048 styrene butadiene rubber Polymers 0.000 description 1
- XLYOFNOQVPJJNP-UHFFFAOYSA-N water Chemical compound O XLYOFNOQVPJJNP-UHFFFAOYSA-N 0.000 description 1
Classifications
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- H—ELECTRICITY
- H01—ELECTRIC ELEMENTS
- H01M—PROCESSES OR MEANS, e.g. BATTERIES, FOR THE DIRECT CONVERSION OF CHEMICAL ENERGY INTO ELECTRICAL ENERGY
- H01M4/00—Electrodes
- H01M4/02—Electrodes composed of, or comprising, active material
- H01M4/13—Electrodes for accumulators with non-aqueous electrolyte, e.g. for lithium-accumulators; Processes of manufacture thereof
- H01M4/131—Electrodes based on mixed oxides or hydroxides, or on mixtures of oxides or hydroxides, e.g. LiCoOx
-
- 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
- H01M10/058—Construction or manufacture
- H01M10/0585—Construction or manufacture of accumulators having only flat construction elements, i.e. flat positive electrodes, flat negative electrodes and flat separators
-
- H—ELECTRICITY
- H01—ELECTRIC ELEMENTS
- H01M—PROCESSES OR MEANS, e.g. BATTERIES, FOR THE DIRECT CONVERSION OF CHEMICAL ENERGY INTO ELECTRICAL ENERGY
- H01M4/00—Electrodes
- H01M4/02—Electrodes composed of, or comprising, active material
- H01M4/36—Selection of substances as active materials, active masses, active liquids
- H01M4/48—Selection of substances as active materials, active masses, active liquids of inorganic oxides or hydroxides
- H01M4/52—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
-
- H—ELECTRICITY
- H01—ELECTRIC ELEMENTS
- H01M—PROCESSES OR MEANS, e.g. BATTERIES, FOR THE DIRECT CONVERSION OF CHEMICAL ENERGY INTO ELECTRICAL ENERGY
- H01M4/00—Electrodes
- H01M4/02—Electrodes composed of, or comprising, active material
- H01M2004/026—Electrodes composed of, or comprising, active material characterised by the polarity
- H01M2004/028—Positive electrodes
-
- H—ELECTRICITY
- H01—ELECTRIC ELEMENTS
- H01M—PROCESSES OR MEANS, e.g. BATTERIES, FOR THE DIRECT CONVERSION OF CHEMICAL ENERGY INTO ELECTRICAL ENERGY
- H01M10/00—Secondary cells; Manufacture thereof
- H01M10/42—Methods or arrangements for servicing or maintenance of secondary cells or secondary half-cells
- H01M2010/4292—Aspects relating to capacity ratio of electrodes/electrolyte or anode/cathode
-
- 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
Abstract
The invention discloses a positive pole piece and a battery, and relates to the technical field of batteries; the positive pole piece comprises a positive pole current collector and a positive pole film layer, wherein the positive pole film layer is arranged on at least one side surface of the positive pole current collector, and a positive active material of the positive pole film layer comprises a lithium metal oxide compound with a layered structure; the thickness of the positive pole piece meets a formula Dm/Dn-1=3.6% -4.3%; wherein Dm is the thickness of the positive electrode sheet when the battery is in a full discharge state 0% SOC after the positive electrode sheet and the negative electrode sheet with the silicon-based material and the carbon-based material are assembled into the full battery; dn is the thickness of the positive electrode sheet at a full charge state of 100% SOC after the positive electrode sheet and the negative electrode sheet having the silicon-based material and the carbon-based material are assembled into a full cell. The positive pole piece can relieve expansion stress caused by a silicon-based negative pole, and is favorable for ensuring the stability of a battery interface so as to improve the cycle performance of the battery.
Description
Technical Field
The invention relates to the technical field of batteries, in particular to a positive pole piece and a battery.
Background
Carbon-based materials, represented by graphite, are the main materials used for the negative electrode of lithium ion batteries, and directly affect the electrochemical performance of lithium ion batteries. With the increasing demand of users on the energy density of lithium ion batteries, silicon-based cathodes have gained great attention and development.
The silicon source is wide, the silicon is one of the elements with extremely high earth crust content abundance, the theoretical specific capacity of the silicon can reach 4200mAh/g, which is more than 10 times of the theoretical capacity (372 mAh/g) of the graphite, and the energy density of the lithium ion battery can be greatly improved. However, the volume change of the silicon-based material is larger than that of the graphite cathode during charging and discharging, and the interface is unstable due to repeated expansion in the cycle process, so that the internal stress of the battery is increased rapidly. Therefore, it is necessary to improve the interfacial stability of the battery by matching a suitable positive electrode material to relieve the expansion stress of the entire battery, so as to ensure the cycle performance of the battery.
In view of the above, the present invention is particularly proposed.
Disclosure of Invention
The invention aims to provide a positive pole piece which can be matched with a silicon-based negative pole, can relieve the expansion stress caused by the silicon-based negative pole, is favorable for ensuring the stability of a battery interface, and can improve the cycle performance of the battery.
Another objective of the present invention is to provide a battery, which includes the above positive electrode plate. Therefore, the battery also has the characteristic of excellent cycle performance.
The embodiment of the invention is realized by the following steps:
in a first aspect, the present invention provides a positive electrode plate, including:
a positive current collector;
the positive electrode active material of the positive electrode film layer comprises a lithium metal oxygen compound with a layered structure;
the thickness of the positive pole piece meets a formula Dm/Dn-1=3.6% -4.3%; wherein Dm is the thickness of the positive electrode sheet when the battery is in a full discharge state 0% SOC after the positive electrode sheet and the negative electrode sheet with the silicon-based material and the carbon-based material are assembled into the full battery; dn is the thickness of the positive electrode sheet at a full charge state of 100% SOC after the positive electrode sheet and the negative electrode sheet having the silicon-based material and the carbon-based material are assembled into a full cell.
In an alternative embodiment, the thickness of the positive electrode sheet satisfies the formula Dm/Dn-1=3.9% -4.2%.
In an alternative embodiment, the positive electrode active material includes single crystal grains and polycrystalline grains, and the polycrystalline grains account for 50 to 95% of the total mass of the positive electrode active material;
and/or the presence of a gas in the gas,
the compacted density PDc of the positive electrode film layer satisfies the following conditions: 3.45g/cm 3 ≤PDc≤3.65g/cm 3 ；
And/or the presence of a gas in the gas,
the mass percentage C of the positive active material in the positive film layer satisfies the following conditions: c is more than or equal to 97 percent;
and/or the presence of a gas in the gas,
the coating surface density rho of the positive electrode film layer is 0.14g/cm 2 <ρc<0.25g/cm 2 。
In an alternative embodiment, the general structural formula of the positive electrode active material is Li a Ni x Co y Mn z A b O 2 (ii) a Wherein 1 < a < 1.08,0.8 < x < 1,0.02 < Y < 0.1,0 < z < 0.2,0 is less than or equal to B < 0.01, A is selected from one or more of Co, al, zr, B, ti, sr, Y, W, la, ba and Mg.
In a second aspect, the present invention provides a battery comprising:
a housing;
a pole piece disposed in the housing, the pole piece including the positive pole piece, the negative pole piece, and the separator of any one of the foregoing embodiments, the negative pole piece including a negative pole current collector and a negative pole film layer disposed on at least one side surface of the negative pole current collector, the negative pole active material of the negative pole film layer including a silicon-based material and a carbon-based material; the isolating film is arranged between the positive pole piece and the negative pole piece;
and the electrolyte is contained in the shell.
In an alternative embodiment, the mass ratio of the silicon-based material to the carbon-based material is (5-70): (30-95);
and/or the presence of a gas in the gas,
the D50 of the silicon-based material meets the condition that the D50 is more than or equal to 6.0um and less than or equal to 18um.
In an alternative embodiment, the silicon-based material comprises at least one of a nano silicon material, a silicon-carbon composite material, silicon oxygen and metal-doped silicon oxygen, wherein a metal element in the metal-doped silicon oxygen is at least one of Li and Mg;
and/or the presence of a gas in the gas,
the carbon-based material comprises at least one of artificial graphite, natural graphite, mesocarbon microbeads and hard carbon.
In an alternative embodiment, the compacted density of the anode film layer PDa satisfies: 1.3g/cm 3 ≤PDa≤1.65g/cm 3 ；
And/or the presence of a gas in the gas,
the coating surface density rho a of the negative electrode film layer is 0.9g/cm 2 <ρa<1.2g/cm 2 。
In alternative embodiments, the barrier film is a polyethylene film, a polypropylene film, or a composite film of polyethylene and polypropylene;
alternatively, the first and second electrodes may be,
the isolation film comprises a substrate and a polymer coating layer arranged on at least one side surface of the substrate, wherein the substrate is a polyethylene film, a polypropylene film or a composite film of polyethylene and polypropylene, and a polymer monomer of the polymer coating layer is selected from at least one of polymethyl methacrylate, polyacrylonitrile, polyethylene oxide, polyvinylidene chloride, polyvinyl acetate and polyvinyl chloride.
In an alternative embodiment, the electrolyte comprises at least one of ethylene carbonate, ethyl methyl carbonate, diethyl carbonate, and further comprises lithium hexafluorophosphate;
alternatively, the first and second electrodes may be,
the electrolyte comprises at least one of ethylene carbonate, ethyl methyl carbonate and diethyl carbonate, lithium hexafluorophosphate and fluoroethylene carbonate, and the mass of the fluoroethylene carbonate accounts for 5-40% of the electrolyte.
The embodiment of the invention has at least the following advantages or beneficial effects:
the positive pole piece provided by the embodiment of the invention comprises a positive pole current collector and a positive pole film layer, wherein the positive pole film layer is arranged on at least one side surface of the positive pole current collector, and a positive active material of the positive pole film layer comprises a lithium metal oxide compound with a layered structure; the thickness of the positive pole piece meets a formula Dm/Dn-1=3.6% -4.3%; wherein Dm is the thickness of the positive electrode sheet when the battery is in a fully discharged state 0% SOC after the positive electrode sheet and the negative electrode sheet having silicon-based material and carbon-based material are assembled into a full battery; dn positive electrode sheet and negative electrode sheet having silicon-based material and carbon-based material were assembled into a full cell, and the cell was at a full state of charge of 100% SOC by the thickness of the positive electrode sheet.
On the one hand, when charging is from 0 to 100 percent of SOC, the thickness of the positive pole piece of the lithium layered metal oxide is gradually reduced and the thickness of the silicon-based negative pole is gradually increased along with the lithium removal of the positive pole, so that the positive pole piece of the lithium layered metal oxide can certainly offset and slow down the expansion force of the whole battery; on the other hand, when the numerical value of Dm/Dn-1 is larger, the structural change of the anode material is large, the volume change is too large, gas generation is caused along with the cracking of the anode material, and the like, so that the cycle deterioration is caused, and when the numerical value of Dm/Dn-1 is smaller, the effect of the environmental expansion of the anode pole piece is weak, so that the cycle performance of the battery is not ensured, therefore, when the numerical value of Dm/Dn-1 is controlled within the range of 3.6% -4.3%, the expansion problem can be effectively solved, and the cycle performance of the battery can be fully improved.
The embodiment of the invention also provides a battery which comprises the positive pole piece. Therefore, the battery also has the characteristic of excellent cycle performance.
Detailed Description
In order to make the objects, technical solutions and advantages of the embodiments of the present invention clearer, the technical solutions in the embodiments of the present invention will be clearly and completely described below. The examples, in which specific conditions are not specified, were conducted under conventional conditions or conditions recommended by the manufacturer. The reagents or instruments used are not indicated by the manufacturer, and are all conventional products available commercially.
The features and properties of the present invention are described in further detail below with reference to examples.
The embodiment of the invention provides a positive pole piece, which is matched with a negative pole piece containing a silicon-based material and a carbon-based material to prepare a battery. Because the volume change of the silicon-based material is larger than that of the graphite cathode during charging and discharging, the interface is unstable due to repeated expansion in the circulation process, so that the internal stress of the battery is increased rapidly. Therefore, it is necessary to improve the interfacial stability of the battery by matching a suitable positive electrode material to relieve the expansion stress of the entire battery, so as to ensure the cycle performance of the battery.
In view of this, the positive electrode plate provided by the embodiment of the invention includes: a positive current collector and a positive film layer; the positive electrode film layer is disposed on at least one side surface of the positive electrode current collector, and preferably disposed on both side surfaces in a thickness direction of the positive electrode current collector. Meanwhile, the positive electrode film layer is obtained by coating positive electrode slurry on a positive electrode current collector and then drying, cold pressing and slitting, and the drying temperature can be 80-130 ℃. The positive electrode slurry comprises a positive electrode active material, a conductive agent, a binder and a solvent, wherein the positive electrode current collector can be selected from aluminum foil, the conductive agent and the binder respectively account for less than 5%, the conductive agent can be selected from carbon black, carbon nano tubes, graphene and the like, the binder can be selected from polyvinylidene fluoride (PVDF), and the solvent can be selected from N-methylpyrrolidone (NMP). The positive active material includes a lithium metal oxide compound having a layered structure. Meanwhile, the thickness of the positive pole piece meets the formula Dm/Dn-1=3.6% -4.3%; wherein Dm is the thickness of the positive electrode sheet when the battery is in a full discharge state 0% SOC after the positive electrode sheet and the negative electrode sheet with the silicon-based material and the carbon-based material are assembled into the full battery; dn is the thickness of the positive electrode sheet at a full charge state of 100% SOC after the positive electrode sheet and the negative electrode sheet having the silicon-based material and the carbon-based material are assembled into a full cell.
On the one hand, in the lithium ion secondary battery, the volume of the general lithium layered metal oxide positive electrode material is continuously reduced along with the change of the volume in the process of positive electrode lithium removal, namely, charging to the SOC increasing, when the SOC is high along with H2/H3, the C axis of the positive electrode material crystal is sharply shrunk, the volume of the material is remarkably reduced, the thickness of the corresponding positive electrode pole piece is remarkably reduced, when the SOC is fully charged to 100%, the thickness Dn is minimum, meanwhile, the silicon-based material of the negative electrode corresponds to the process of lithium embedding, and as the SOC increases, the silicon material of the negative electrode is embedded with lithium and expands, and the negative electrode pole piece becomes thicker. Therefore, when charging from 0 to 100% SOC, the thickness of the positive electrode plate of the lithium layered metal oxide is gradually reduced and the thickness of the silicon-based negative electrode is gradually increased as the positive electrode is delithiated, so that the positive electrode plate of the lithium layered metal oxide can certainly offset and slow the expansive force of the entire battery;
on the other hand, when the numerical value of Dm/Dn-1 is larger, the structural change of the anode material is large, the volume change is too large, gas generation is caused along with the cracking of the anode material, and the like, so that the cycle deterioration is caused, and when the numerical value of Dm/Dn-1 is smaller, the effect of the environmental expansion of the anode pole piece is weak, so that the cycle performance of the battery is not ensured, therefore, when the numerical value of Dm/Dn-1 is controlled within the range of 3.6% -4.3%, the expansion problem can be effectively solved, and the cycle performance of the battery can be fully improved.
As an optional scheme, the thickness of the positive electrode piece satisfies the formula Dm/Dn-1=3.9% -4.2%. When Dm/Dn-1 is controlled to be in the range of 3.9% -4.2%, the cycle performance can be optimized while the expansion stress is small.
Further optionally, in an embodiment of the present invention, the mass percentage C of the cathode active material in the cathode film layer satisfies: c is more than or equal to 97 percent. The general formula of the positive active material is Li a Ni x Co y Mn z A b O 2 (ii) a Wherein 1 < a < 1.08,0.8 < x < 1,0.02 < Y < 0.1,0 < z < 0.2,0 is less than or equal to B < 0.01, A is selected from one or more of Co, al, zr, B, ti, sr, Y, W, la, ba and Mg. The metal element A is coated on the surface of the positive electrode material particles in a coating mode. The performance of the pole piece can be ensured by controlling the quality of the positive active material so as to ensure the electrochemical performance of the battery. By doping metal elements in the positive electrode active material, the dynamic performance and gram volume of the positive electrode active material can be improved. Of course, in other embodiments, the metal element a may not be doped, and the embodiments of the present invention are not limited.
Meanwhile, the positive electrode active material includes single crystal grains and polycrystalline grains, and the polycrystalline grains account for 50-95% of the total mass of the positive electrode active material. The reasonable collocation of the polycrystalline particles and the single crystal particles can improve the compaction density and the energy density of the battery so as to further improve the electrochemical performance of the battery.
Further, in embodiments of the present invention, the positive electrode film layer has a compacted density PDc ofFoot: 3.45g/cm 3 ≤PDc≤3.65g/cm 3 (ii) a The coating surface density rho of the positive film layer is 0.14g/cm 2 <ρc<0.25g/cm 2 . The compaction density of the positive pole piece is closely related to the specific capacity, efficiency, internal resistance and battery cycle performance of the material, and when the compaction density PDc of the positive pole film layer is controlled within the range, the energy density can be ensured, and the cycle performance of the battery can be further improved. The surface density of the positive electrode film layer is large, so that the internal resistance is large, the power performance can be weakened, the surface density is small, the thickness of the pole piece is thinned, and the energy density of the battery is not ensured. Therefore, the coating surface density of the pole piece film layer is controlled within the range, so that the power performance of the battery can be ensured, and the cycle performance of the battery can be ensured.
The embodiment of the invention also provides a battery comprising the positive pole piece. It can be either a square cell or a cylindrical or pouch cell. The battery specifically comprises a shell, a pole core and electrolyte. The pole core is arranged in the shell and comprises the positive pole piece, the negative pole piece and the isolating membrane of any one of the previous embodiments. The isolating film is arranged between the positive pole piece and the negative pole piece. The electrolyte is contained in the shell and used for ensuring that the lithium ion deintercalation can be normally carried out.
In detail, the negative electrode sheet includes a negative electrode current collector and a negative electrode film layer disposed on at least one side surface of the negative electrode current collector, and preferably, both side surfaces in a thickness direction of the negative electrode current collector are provided with the negative electrode film layer. And the negative current collector can be selected from copper foil, the negative film layer is obtained by coating the negative slurry on the negative current collector, drying and cold pressing, and the drying temperature is 80-120 ℃. The negative electrode slurry comprises a negative electrode active material, a conductive agent, a binder and a solvent. The amount of conductive agent may be less than 5%, the amount of binder may be less than 5% or greater than 5%, and the embodiments of the present invention are illustrated with both less than 5%. Meanwhile, the negative active material comprises a silicon-based material, and the conductive agent can be at least one selected from conductive carbon black, conductive graphite, vapor-grown carbon fiber and carbon nanotube, such as conductive carbon black and single-walled carbon tube which can be selected as (1-2): 0.1. The binder may be selected to be styrene-butadiene rubber and the solvent may be selected to be N-methylpyrrolidone (NMP).
The isolating film is a polyethylene film, a polypropylene film or a composite film of polyethylene and polypropylene; or, the isolation film comprises a substrate and a polymer coating layer arranged on at least one side surface of the substrate, the substrate is a polyethylene film, a polypropylene film or a composite film of polyethylene and polypropylene, and the polymer monomer of the polymer coating layer is selected from at least one of polymethyl methacrylate, polyacrylonitrile, polyethylene oxide, polyvinylidene chloride, polyvinyl acetate and polyvinyl chloride. Illustratively, the release film comprises a substrate and two polymer coatings arranged in the thickness direction of the substrate, wherein the substrate is a polyethylene film, the polymer monomer of the polymer coatings is polymethyl methacrylate, and the thickness of the single-side coating is 3um. Through the arrangement of the polymer coating, the liquid absorption amount of the diaphragm can be increased so as to further improve the cycle performance of the battery, and the thermal shrinkage of the diaphragm can be reduced so as to improve the safety performance of the battery.
The electrolyte comprises at least one of ethylene carbonate, ethyl methyl carbonate and diethyl carbonate, and also comprises lithium hexafluorophosphate. Or the electrolyte comprises at least one of ethylene carbonate, ethyl methyl carbonate and diethyl carbonate, lithium hexafluorophosphate and fluoroethylene carbonate, and the mass of the fluoroethylene carbonate accounts for 5-40% of the electrolyte. Illustratively, the electrolyte is a 1M solution prepared by mixing ethylene carbonate, ethyl methyl carbonate and diethyl carbonate according to the volume ratio of 1 (4-7) to (1-4), adding fluoroethylene carbonate, controlling the mass fraction of the fluoroethylene carbonate to be 10%, and finally adding lithium hexafluorophosphate. The electrochemical window of the electrolyte can be widened by adding fluoroethylene carbonate, a stable solid electrolyte interface SEI film can be formed, a compact structure layer is formed without increasing impedance, so that the cycle performance of the battery can be further improved, and the electrolyte can be prevented from being further decomposed, so that the normal-temperature performance of the electrolyte can be improved.
Alternatively, in the embodiment of the present invention, the mass ratio of the silicon-based material to the carbon-based material is (5-70): (30-95); preferably, the mass ratio of the silicon-based material to the carbon-based material is (5-35): (95-65). D50 of the silicon-based material meets the condition that D50 is more than or equal to 6.0um and less than or equal to 18um; the silicon-based material comprises at least one of nano silicon material, silicon-carbon composite material, silicon oxygen and metal doped silicon oxygen, wherein the metal element in the metal doped silicon oxygen is at least one of Li and Mg. The negative active material further includes artificial graphite. The carbon-based material includes at least one of artificial graphite, natural graphite, mesocarbon microbeads and hard carbon. Illustratively, the embodiment of the invention mainly uses metal doped lithium silicon oxygen as a silicon-based material and artificial graphite as a carbon-based material.
On one hand, the expansion degree can be controlled to a certain degree by controlling the proportion and the granularity of the silicon-based material in the negative active material, so that the energy density is ensured, and meanwhile, the expansion degree is matched with the positive pole piece, and the cycle performance of the battery can be fully ensured through the positive pole piece. On the other hand, other components of the cathode active material are reasonably matched, so that the cathode active material can be matched with the silicon-based material, the capacity density of the battery is further ensured, and the safety performance of the battery is ensured.
Further optionally, in an embodiment of the present invention, the compacted density PDa of the negative electrode film layer satisfies: 1.3g/cm 3 ≤PDa≤1.65g/cm 3 (ii) a The coating surface density rho a of the negative electrode film layer is 0.9g/cm 2 <ρa<1.2g/cm 2 . The compaction density of the negative pole piece is closely related to the specific capacity, efficiency, internal resistance and battery cycle performance of the material, and when the compaction density PDa of the negative pole film layer is controlled within the range, the capacity density can be ensured, and the cycle performance of the battery can be further improved. The surface density of the negative electrode film layer is large, so that the internal resistance is large, the power performance can be weakened, the surface density is small, the thickness of the pole piece is thinned, the side reaction is aggravated, and the cycle performance of the battery is not ensured. Therefore, the coating surface density of the pole piece film layer is controlled within the range, so that the power performance of the battery can be ensured, and the cycle performance of the battery can be ensured.
The performances of the positive electrode plate and the battery provided by the invention are described in detail through specific examples and comparative examples as follows:
example 1
The present example provides a battery, which is prepared by the following method:
s1: preparing a positive pole piece:
mixing a positive electrode active material, conductive carbon black and a binder PVDF, adding dry NMP, and uniformly stirring to obtain positive electrode slurry; coating the positive electrode slurry on two side surfaces of the aluminum foil in the thickness direction, and drying, cold-pressing and cutting to obtain a positive electrode piece;
s2: preparing a negative pole piece:
mixing a silicon-based material, artificial graphite, conductive carbon black, a single-walled carbon tube and a binder, adding deionized water, and uniformly stirring to obtain a negative electrode slurry; coating the negative electrode slurry on two side surfaces of the copper foil in the thickness direction, and drying, cold-pressing and slitting to obtain a negative electrode piece;
s3: preparing an electrolyte:
mixing ethylene carbonate, ethyl methyl carbonate and diethyl carbonate, adding fluoroethylene carbonate, and finally adding lithium hexafluorophosphate to prepare a 1M solution;
s4: assembling the battery:
assembling the positive pole piece, the isolating membrane and the negative pole piece in sequence to be laminated or wound to form a pole core; and baking, packaging, forming, grading and the like the pole core to obtain the finished lithium ion secondary battery.
Meanwhile, the parameters in the process of preparing the battery in example 1 are shown in table 1:
TABLE 1 example 1 parameters
Example 2
This embodiment provides a battery which differs from embodiment 1 in that in this embodiment, each parameter selection is as shown in table 2.
TABLE 2 parameters of example 2
Example 3
This embodiment provides a battery which differs from embodiment 1 in that in this embodiment, each parameter selection is as shown in table 3.
TABLE 3 parameters of example 3
Example 4
The present embodiment provides a battery which is different from embodiment 1 in that, in the present embodiment, each parameter selection is as shown in table 4.
TABLE 4 example 4 parameters
Example 5
This embodiment provides a battery which differs from embodiment 1 in that in this embodiment, each parameter selection is as shown in table 5.
TABLE 5 parameters of example 5
Example 6
This embodiment provides a battery which differs from embodiment 1 in that in this embodiment, each parameter selection is as shown in table 6.
TABLE 6 parameters of example 6
Example 7
This embodiment provides a battery which differs from embodiment 1 in that in this embodiment, each parameter selection is as shown in table 7.
TABLE 7 parameters of example 7
Example 8
This embodiment provides a battery which differs from embodiment 1 in that in this embodiment, each parameter selection is as shown in table 8.
TABLE 8 parameters of example 8
Example 9
This embodiment provides a battery which is different from embodiment 1 in that in this embodiment, each parameter selection is as shown in table 9.
TABLE 9 parameters of example 9
Example 10
This embodiment provides a battery which is different from embodiment 1 in that in this embodiment, each parameter selection is as shown in table 10.
TABLE 10 parameters of example 10
Example 11
This embodiment provides a battery which is different from embodiment 1 in that in this embodiment, each parameter selection is as shown in table 11.
TABLE 11 parameters of example 11
Comparative example 1
Comparative example 1 provides a battery that differs from the battery provided in example 1 in that the selection of parameters is shown in table 12.
TABLE 12 parameters of comparative example 1
Comparative example 2
Comparative example 2 provides a battery which differs from the battery provided in example 1 in that the parameter choices are shown in table 13.
TABLE 13 parameters of comparative example 2
Comparative example 3
Comparative example 3 provides a battery that differs from the battery provided in example 1 in that the parameter choices are shown in table 14.
TABLE 14 parameters of comparative example 3
Comparative example 4
Comparative example 4 provides a battery which differs from the battery provided in example 1 in that the parameter choices are shown in table 15.
TABLE 15 comparative example 4 parameters
Experimental example 1
The batteries provided in examples 1 to 11 and comparative examples 1 to 4 were subjected to constant current charging at a rate of 0.5C to a voltage of 4.25V at 25 ± 1 ℃, followed by constant voltage charging at a voltage of 4.25V to a current of 0.05C, left standing for 15 minutes, constant current discharging at a rate of 1C to a voltage of 2.85V, and the above procedure was repeated for 400 cycles to test the cycle retention ratio of each battery, with the test results shown in table 16.
TABLE 16 results of the cycling tests
As can be seen from comparison of examples 1 to 11 with comparative examples 1 to 4 in Table 16, the batteries prepared in examples of the present invention have more excellent cycle characteristics. Meanwhile, as can be seen from the differences between examples 1 to 3 and example 4, the cycle performance can be improved to some extent by doping the element a. As can be seen from comparison of examples 1 to 4 with examples 5 to 6, the adjustment of the polycrystalline fraction does not greatly affect the cycle performance of the battery at normal temperature, but since the polycrystalline fraction also affects the capacity and the energy density, it is preferably controlled to be between 50 and 98%, and more preferably to be around 80%. It can be seen from the comparison of examples 1 to 4 with examples 7 to 9 that, when the silicon-based material content is the same, the cycle of silicon oxygen without doping lithium is better than the cycle of doping lithium, and doping Li can improve the gram capacity of the first efficiency and the whole battery of the battery to some extent, increase the energy density, so that the scheme with metal doping is preferred. Meanwhile, the lower the content of lithium-doped silicon oxide is, the smaller the expansion is, the higher the stability is, and the better the cycle performance is, but considering that the lithium-doped silicon oxide can also influence the energy density, the lithium-doped silicon oxide and the graphite are controlled to be (5-70): about (30-95) is suitable, and the ratio can be controlled to be (5-35): (65-95) to ensure both energy density and cycle performance. As can be seen from comparison of examples 1-4 with examples 10 and 11, the cycle performance of the battery is improved to some extent by adding fluoroethylene carbonate, and the effect is better when the fluoroethylene carbonate is controlled to be about 10%.
In summary, the embodiments of the present invention provide an anode plate capable of being matched with a silicon-based cathode, which can relieve the expansion stress caused by the silicon-based cathode, and is beneficial to ensuring the stability of the battery interface, so as to improve the cycle performance of the battery. The embodiment of the invention also provides a battery which comprises the positive pole piece. Therefore, the battery also has the characteristic of excellent cycle performance.
The above description is only a preferred embodiment of the present invention and is not intended to limit the present invention, and various modifications and changes may be made by those skilled in the art. Any modification, equivalent replacement, or improvement made within the spirit and principle of the present invention should be included in the protection scope of the present invention.
Claims (10)
1. A positive electrode sheet, comprising:
a positive current collector;
the positive electrode film layer is arranged on at least one side surface of the positive electrode current collector, and the positive electrode active material of the positive electrode film layer comprises a lithium metal oxygen compound with a layered structure;
the thickness of the positive pole piece meets the formula Dm/Dn-1=3.6% -4.3%; wherein Dm is the thickness of the positive electrode sheet when the battery is in a full discharge state 0% SOC after the positive electrode sheet and the negative electrode sheet with the silicon-based material, the carbon-based material and the carbon-based material are assembled into the full battery; dn is the thickness of the positive electrode sheet at a full charge state of 100% SOC after the positive electrode sheet and the negative electrode sheet having the silicon-based material and the carbon-based material are assembled into a full cell.
2. The positive electrode sheet according to claim 1, wherein:
the thickness of the positive pole piece meets the formula Dm/Dn-1=3.9% -4.2%.
3. The positive electrode sheet according to claim 1, wherein:
the positive electrode active material comprises single crystal particles and polycrystalline particles, and the polycrystalline particles account for 50-95% of the total mass of the positive electrode active material;
and/or the presence of a gas in the gas,
the compacted density PDc of the positive electrode film layer satisfies the following conditions: 3.45g/cm 3 ≤PDc≤3.65g/cm 3 ；
And/or the presence of a gas in the gas,
the mass percentage C of the positive electrode active material in the positive electrode film layer satisfies the following condition: c is more than or equal to 97 percent;
and/or the presence of a gas in the gas,
the coating surface density rho of the positive electrode film layer is 0.14g/cm 2 <ρc<0.25g/cm 2 。
4. The positive electrode sheet according to claim 1, characterized in that:
the general structural formula of the positive active material is Li a Ni x Co y Mn z A b O 2 (ii) a Wherein 1 < a < 1.08,0.8 < x < 1,0.02 < Y < 0.1,0 < Y < 0.2,0 is less than or equal to B < 0.01, A is selected from one or more of Co, al, zr, B, ti, sr, Y, W, la, ba and Mg.
5. A battery, comprising:
a housing;
a pole piece disposed in the case, including the positive pole piece, the negative pole piece, and the separator of any one of claims 1 to 4, the negative pole piece including a negative current collector and a negative pole film layer disposed on at least one side surface of the negative current collector, the negative active material of the negative pole film layer including a silicon-based material and a carbon-based material; the isolating film is arranged between the positive pole piece and the negative pole piece;
and the electrolyte is contained in the shell.
6. The battery of claim 5, wherein:
the mass ratio of the silicon-based material to the carbon-based material is (5-70): (30-95);
and/or the presence of a gas in the atmosphere,
the D50 of the silicon-based material meets the condition that the D50 is more than or equal to 6.0um and less than or equal to 18um.
7. The battery of claim 5, wherein:
the silicon-based material comprises at least one of a nano silicon material, a silicon-carbon composite material, silicon oxygen and metal-doped silicon oxygen, wherein a metal element in the metal-doped silicon oxygen is at least one of Li and Mg;
and/or the presence of a gas in the gas,
the carbon-based material includes at least one of artificial graphite, natural graphite, mesocarbon microbeads and hard carbon.
8. The battery of claim 5, wherein:
the compacted density PDa of the negative electrode film layer meets the following conditions: 1.3g/cm 3 ≤PDa≤1.65g/cm 3 ；
And/or the presence of a gas in the gas,
the coating surface density rho a of the negative electrode film layer is 0.9g/cm 2 <ρa<1.2g/cm 2 。
9. The battery of claim 5, wherein:
the isolating film is a polyethylene film, a polypropylene film or a composite film of polyethylene and polypropylene;
alternatively, the first and second electrodes may be,
the isolating film comprises a substrate and a polymer coating layer arranged on at least one side surface of the substrate, wherein the substrate is a polyethylene film, a polypropylene film or a composite film of polyethylene and polypropylene, and the polymer monomer of the polymer coating layer is selected from at least one of polymethyl methacrylate, polyacrylonitrile, polyethylene oxide, polyvinylidene chloride, polyvinyl acetate and polyvinyl chloride.
10. The battery of claim 5, wherein:
the electrolyte comprises at least one of ethylene carbonate, ethyl methyl carbonate and diethyl carbonate, and also comprises lithium hexafluorophosphate;
alternatively, the first and second electrodes may be,
the electrolyte comprises at least one of ethylene carbonate, ethyl methyl carbonate and diethyl carbonate, lithium hexafluorophosphate and fluoroethylene carbonate, and the mass of the fluoroethylene carbonate accounts for 5-40% of the electrolyte.
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Citations (6)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN108808072A (en) * | 2018-06-29 | 2018-11-13 | 宁德时代新能源科技股份有限公司 | Lithium ion battery |
| KR20190042850A (en) * | 2017-10-17 | 2019-04-25 | 에스케이이노베이션 주식회사 | Lithium secondary battery |
| KR20190064462A (en) * | 2017-11-30 | 2019-06-10 | 주식회사 엘지화학 | Cathode Having Double Active Material Layers and Lithium Secondary Battery Comprising the Same |
| CN112216822A (en) * | 2019-07-10 | 2021-01-12 | 宁德时代新能源科技股份有限公司 | Lithium ion secondary battery and preparation method thereof |
| CN112582596A (en) * | 2019-09-27 | 2021-03-30 | 宁德时代新能源科技股份有限公司 | Secondary battery, battery module, battery pack and device containing same |
| CN113140726A (en) * | 2020-03-18 | 2021-07-20 | 宁德新能源科技有限公司 | Electrochemical device |
-
2022
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Patent Citations (6)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| KR20190042850A (en) * | 2017-10-17 | 2019-04-25 | 에스케이이노베이션 주식회사 | Lithium secondary battery |
| KR20190064462A (en) * | 2017-11-30 | 2019-06-10 | 주식회사 엘지화학 | Cathode Having Double Active Material Layers and Lithium Secondary Battery Comprising the Same |
| CN108808072A (en) * | 2018-06-29 | 2018-11-13 | 宁德时代新能源科技股份有限公司 | Lithium ion battery |
| CN112216822A (en) * | 2019-07-10 | 2021-01-12 | 宁德时代新能源科技股份有限公司 | Lithium ion secondary battery and preparation method thereof |
| CN112582596A (en) * | 2019-09-27 | 2021-03-30 | 宁德时代新能源科技股份有限公司 | Secondary battery, battery module, battery pack and device containing same |
| CN113140726A (en) * | 2020-03-18 | 2021-07-20 | 宁德新能源科技有限公司 | Electrochemical device |
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