CN115172649A - Negative plate, battery and method for preparing battery - Google Patents
Negative plate, battery and method for preparing battery Download PDFInfo
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- CN115172649A CN115172649A CN202210699160.4A CN202210699160A CN115172649A CN 115172649 A CN115172649 A CN 115172649A CN 202210699160 A CN202210699160 A CN 202210699160A CN 115172649 A CN115172649 A CN 115172649A
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- 239000006183 anode active material Substances 0.000 claims abstract description 15
- 238000003475 lamination Methods 0.000 claims abstract description 7
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- 239000011230 binding agent Substances 0.000 claims description 26
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Images
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
-
- 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
-
- 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
- H01M4/362—Composites
- H01M4/366—Composites as layered products
-
- 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
- H01M4/621—Binders
-
- 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
- H01M2004/027—Negative electrodes
-
- 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
-
- Y—GENERAL TAGGING OF NEW TECHNOLOGICAL DEVELOPMENTS; GENERAL TAGGING OF CROSS-SECTIONAL TECHNOLOGIES SPANNING OVER SEVERAL SECTIONS OF THE IPC; TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS
- Y02—TECHNOLOGIES OR APPLICATIONS FOR MITIGATION OR ADAPTATION AGAINST CLIMATE CHANGE
- Y02P—CLIMATE CHANGE MITIGATION TECHNOLOGIES IN THE PRODUCTION OR PROCESSING OF GOODS
- Y02P70/00—Climate change mitigation technologies in the production process for final industrial or consumer products
- Y02P70/50—Manufacturing or production processes characterised by the final manufactured product
Landscapes
- Chemical & Material Sciences (AREA)
- Chemical Kinetics & Catalysis (AREA)
- Electrochemistry (AREA)
- General Chemical & Material Sciences (AREA)
- Engineering & Computer Science (AREA)
- Materials Engineering (AREA)
- Manufacturing & Machinery (AREA)
- Composite Materials (AREA)
- Battery Electrode And Active Subsutance (AREA)
Abstract
The invention discloses a negative plate, a battery and a method for preparing the battery. The negative plate comprises a negative current collector, a negative active material layer and a bonding coating, wherein the negative active material layer is arranged on the negative current collector; the binding coat is provided on at least a part of a surface of the anode active material layer, and includes binding regions and gap regions alternately provided with the binding regions and/or provided around the binding regions. This negative pole piece is through forming bonding area on active material layer surface, not only helps improving the adhesion between diaphragm and the negative pole piece in the heat recombination lamination battery, and the interval of a plurality of bonding areas is arranged and is still helped the infiltration and the guarantor of electrolyte moreover for battery cycle property and life all obtain promoting, security performance when having guaranteed the battery and using, can solve the difficult long-size electric core of matching of traditional heat recombination technology, the adhesion is inhomogeneous, the adhesion is difficult for not opening gluey scheduling problem by force.
Description
Technical Field
The invention belongs to the field of batteries, and particularly relates to a negative plate, a battery and a method for preparing the battery.
Background
Thermal compounding, namely, performing high-temperature and high-pressure treatment on the battery cell for a certain time to bond the diaphragm and the pole piece, particularly the negative pole piece together, so as to achieve the following steps: the flatness of the battery cell is improved, and the thickness meets the requirement; (2) The stacking unit (or pole core) can enter the shell conveniently, and the hardness of the long-size soft-package battery cell is ensured so as to prevent the battery cell from deforming; (3) The positive and negative electrodes are tightly combined together, and Li is shortened + The transmission path improves the performance such as multiplying power and power; (4) The positive and negative pole pieces are prevented from being misplaced in the long-term use process, and the safety risk is reduced; (5) The uniform gel state layer on the surface of the electrode has a buffering effect on burr foreign matters, so that the risk of internal short circuit is reduced; (6) The electrochemical reaction in each area is uniform, the risk of lithium precipitation caused by nonuniform current is reduced, the safety is improved, the service life of the battery cell is prolonged, and the like.
At present, a gluing diaphragm and positive and negative pole pieces are generally selected to form a stacking unit in a thermal compounding process, the glue layer on the diaphragm has viscosity through heating and pressurizing treatment, and then the adhesion of positive and negative active substances, a binder and the diaphragm is realized. However, such a conventional thermal compounding process has the following problems: (1) Because the negative electrode is often weaker in polarity, lower in roughness and weaker in binding power formed by the negative electrode and the diaphragm, the negative electrode is very easy to fall off from the diaphragm in a layering mode when enough binding power cannot be guaranteed in the thermal compounding process, the manufacturing process of the battery cell is influenced, the risk of glue opening after liquid injection exists, and the yield, the rate capability and the cycle performance of the battery cell are finally influenced. (2) The adhesive force of the glue on the surface of the glued diaphragm is obviously influenced by the temperature, and because the time of high-temperature and high-pressure treatment in the thermal compounding process is short, the surface of the electrode plate is coated with electrode materials, all parts of the electrode plate are heated unevenly, and the adhesive force with the diaphragm is uneven. The prepared battery has uneven local current during charging and discharging, and can generate potential safety hazards such as black spots, lithium precipitation and the like. (3) In actual production, the thickness of the pole piece fluctuates, the periphery is generally thinner than the middle, the thickness of the pole piece is inconsistent, the thickness of each area of the stacking unit is inconsistent in the hot pressing process, and the adhesive force of the diaphragm is uneven. (4) The conventional thermal compounding process is suitable for preparing a battery with a smaller size. But when the pole piece size is longer, when needing wider range diaphragm, the adhesion strength size and the homogeneity of traditional heat recombination technology just are difficult to guarantee, have increased the unit of piling up (or the pole piece) and have steadily gone into the shell degree of difficulty and long-size soft package electricity core deformation possibility.
Disclosure of Invention
The present invention is directed to solving, at least to some extent, one of the technical problems in the related art. Therefore, the invention aims to provide a negative plate, a battery and a method for preparing the battery, so as to solve the problems that the traditional thermal compounding process is difficult to match a long-size battery core, the binding force is not uniform, the binding property is not strong, the glue is not easy to open and the like.
In one aspect of the present invention, a negative electrode sheet is provided. According to an embodiment of the present invention, the negative electrode tab includes:
a negative current collector;
a negative electrode active material layer provided on the negative electrode current collector;
a binder coating provided on at least a part of a surface of the anode active material layer, the binder coating including a binder region and a gap region alternately provided with the binder region and/or provided around the binder region.
Compared with the prior art, the negative plate of the embodiment of the invention has the following beneficial effects: firstly, the bonding area in the bonding coating formed on the surface of the negative plate strengthens the bonding force and the bonding uniformity between the negative plate and the diaphragm in the thermal composite laminated battery, and shortens Li + The transmission path reduces the possibility of glue failure after liquid injection, each area can uniformly perform electrochemical reaction, and uneven current bands are reducedThe lithium separation risk is increased, the safety is improved, meanwhile, the service life of the battery core is easily prolonged due to a uniform interface, and the cycle performance of the battery is improved; secondly, the structure and the composition of the bonding coating can not obstruct Li + And the electrolyte is transmitted, so that the normal use of the battery is ensured; thirdly, the gap area in the bonding coat is not provided with the bonding coat, and is equivalent to a spacing channel which can lead Li + After the battery is injected with the electrolyte, the electrolyte more effectively soaks the negative plate, so that the energy density of the battery is improved, meanwhile, the electrolyte is also beneficial to the liquid retention of the electrolyte, and the cycle life and the dynamic performance of the battery can be improved; fourthly, the flatness of the lithium ion battery can be improved when the laminated battery is prepared by thermal compounding, the thickness of the battery cell meets the requirement, or the laminated battery cell is favorable for entering the shell, and the hardness of the long-size soft-packaged battery cell is ensured so as to prevent the battery cell from deforming; prevent positive negative pole piece dislocation in the long-term use, reduce the safety risk.
In addition, the negative electrode sheet according to the above embodiment of the present invention may further have the following additional technical features:
in some embodiments of the invention, the bond region comprises: 85-95 parts of macromolecular organic matter, 1-6 parts of binder and 1-5 parts of thickening agent.
In some embodiments of the present invention, the negative electrode sheet satisfies at least one of the following conditions: the polymer organic matter comprises at least one selected from carboxymethyl cellulose, polymethyl methacrylate, polyvinyl acetate, polyvinyl sulfite, polyethylene carbonate, polymethyl vinyl sulfone and polyethylene vinyl sulfone; the binder is at least one selected from polyvinylidene fluoride, polyethylene oxide, polyether, polymethyl methacrylate, polyacrylonitrile, sodium carboxymethyl cellulose, lithium carboxymethyl cellulose, polyvinylidene fluoride and polyethylene glycol; the thickening agent is styrene butadiene rubber; the bonding slurry for forming the bonding area takes water and/or N-methyl pyrrolidone as a solvent, and the solid content of the bonding slurry is 1.5-2 wt%.
In some embodiments of the present invention, the negative electrode sheet satisfies at least one of the following conditions: the thickness of the bonding coating is 1-10 mu m; the bonding coating comprises a plurality of bonding areas distributed at intervals, and the area where the bonding areas are not arranged is the gap area; the ratio of the total projected area of the bonding region on the negative electrode active material layer to the total projected area of the gap region on the negative electrode active material layer is 25% to 100%.
In some embodiments of the present invention, a plurality of the bonding regions are arranged at intervals in an array; and/or the width direction of the bonding area is the same as the length direction of the negative current collector, and the width of each bonding area is 0.5-3 cm.
In some embodiments of the present invention, the active slurry for forming the negative electrode active material layer includes 90 to 97 parts by weight of graphite, 0 to 2 parts by weight of superconducting carbon black, 1 to 3 parts by weight of carboxymethyl cellulose, and 1 to 4 parts by weight of styrene-butadiene rubber; and/or the total thickness of the negative electrode current collector and the negative electrode active material layer is 100 to 150 μm.
In yet another aspect of the present invention, a battery is provided. According to an embodiment of the present invention, the battery includes: the negative pole piece, the diaphragm and the positive pole piece are alternately stacked, the gluing diaphragm is arranged between the two adjacent negative pole pieces and the positive pole piece, and the adhesive coating is arranged on one side of the negative pole piece facing the gluing diaphragm.
Compared with the prior art, the battery of the embodiment of the invention has the following beneficial effects: 1) The bonding region in the bonding coating formed on the surface of the negative electrode active material layer can overcome the problems of weak bonding between the negative electrode sheet and the diaphragm, and easy layering and negative electrode falling in the use process of the battery in the related technology, and shorten Li + The transmission path improves the power performance of the battery. 2) The binding power and the uniformity of the binding power between the negative plate and the diaphragm can be improved, so that the electrochemical performance of each part of the battery is uniform, and potential safety hazards such as black spots, lithium precipitation and the like are avoided; in the charge-discharge cycle of the battery, the temperature difference caused by different heat dissipation capacities of all parts of the battery cell can be reduced, and the cycle performance and the safety performance of the battery cell are improved. 3) The increase of the cohesive force between negative pole piece and the diaphragm conveniently piles up the unit and goes into the aluminum hull or guarantees soft-packaged electrical core intensity non-deformable. 4) Shape of clearance zoneThe formed channel can enable the electrolyte to more effectively infiltrate the negative plate after the lithium ion battery is injected with the electrolyte, so that the energy density of the battery is improved; meanwhile, the electrolyte is also beneficial to the liquid retention of the electrolyte, so that the cycle performance and the service life of the battery are improved, and the safety performance of the battery in use is ensured.
In some embodiments of the present invention, the positive electrode sheet includes a positive electrode collector and a positive electrode active material layer provided on the positive electrode collector, and the active slurry for forming the positive electrode active material layer includes: 94-98 parts of nickel-cobalt-manganese ternary positive electrode active material, 0.5-2 parts of superconducting carbon black, 0.3-2 parts of carbon nano tube and 0.5-3 parts of polyvinylidene fluoride, wherein the solid content of the active slurry is 70-72 wt%; and/or the negative plate adopts a copper foil as a negative current collector, and the positive plate adopts an aluminum foil as a positive current collector.
In yet another aspect of the invention, the invention provides a method of making a battery as described above. According to an embodiment of the invention, the method comprises:
(1) Coating negative active slurry on a negative current collector to form a negative active material layer, and forming a bonding area and a gap area on the negative active material layer so as to obtain a negative plate;
(2) Coating the positive active slurry on a positive current collector to form a positive active substance layer so as to obtain a positive plate;
(3) Gluing the diaphragm, and laminating the negative plate, the glued diaphragm and the positive plate to obtain a laminated unit;
(4) And carrying out hot-press compounding on the laminated unit so as to obtain the battery.
Compared with the prior art, the method for preparing the battery in the embodiment of the invention has a simple process, has all the technical characteristics and beneficial effects of the battery (no repeated description is given here), and can effectively solve the problems that the traditional thermal compounding process is difficult to match with a long-size battery core, the bonding force is not uniform, the bonding property is not strong, the glue is not easy to open, and the like.
In some embodiments of the invention, the pressure of the hot-pressing compounding is 0.62-0.68 MPa, the temperature is 80-86 ℃, and the time is 1-5 min.
In some embodiments of the present invention, the hot press compounding further comprises: the method comprises the following working procedures of battery cell shell entering, baking, liquid injection, formation, high-temperature shelving, capacity grading, high-temperature aging and normal-temperature aging.
Additional aspects and advantages of the invention will be set forth in part in the description which follows and, in part, will be obvious from the description, or may be learned by practice of the invention.
Drawings
The above and/or additional aspects and advantages of the present invention will become apparent and readily appreciated from the following description of the embodiments, taken in conjunction with the accompanying drawings of which:
fig. 1 is a schematic view of the structure of a negative electrode sheet according to one embodiment of the present invention (the bonding region is rectangular).
Fig. 2 is a plan view of the negative electrode sheet according to example 1 of the present invention.
Fig. 3 is a plan view of a negative electrode sheet according to still another embodiment of the present invention (the bonding region is square).
Fig. 4 is a top view of a negative electrode tab according to yet another embodiment of the present invention (the bonded region has a parallelogram shape).
Detailed Description
Reference will now be made in detail to embodiments of the present invention, examples of which are illustrated in the accompanying drawings, wherein like reference numerals refer to the same or similar elements or elements having the same or similar functions throughout. The embodiments described below with reference to the accompanying drawings are illustrative and intended to explain the present invention and should not be construed as limiting the present invention.
In the description of the present invention, it should be understood that the terms "length", "width", "thickness", and the like, indicate orientations or positional relationships based on those shown in the drawings, are merely for convenience in describing the present invention and simplifying the description, and do not indicate or imply that the device or element referred to must have a particular orientation, be constructed and operated in a particular orientation, and thus, should not be construed as limiting the present invention. Further, in the description of the present invention, "a plurality" means at least two, e.g., two, three, etc., unless specifically limited otherwise.
In one aspect of the present invention, a negative electrode sheet is provided. According to an embodiment of the present invention, as understood with reference to fig. 1 to 2, the negative electrode tab includes: a binder coating 10, a negative electrode active material layer 20, and a negative electrode current collector 30, wherein the negative electrode active material layer 20 is provided on the negative electrode current collector 10; the bond coat 10 is provided on at least a part of the surface of the anode active material layer 20, the bond coat 10 includes bond regions 11 and gap regions 12, and the gap regions 12 are alternately arranged with the bond regions 11 and/or are arranged around the bond regions 11 (note that the gap regions are regions of the anode active material layer not coated with the bond coat). It is to be understood that fig. 1 and 2 are only simple schematic diagrams, and in actual production, the negative active material layer 20 may be provided on all surfaces of the negative current collector 30, including the upper surface and the lower surface of the negative current collector 30, and when the negative current collector 30 has a through hole, the negative active material layer 20 may also penetrate through the through hole on the negative current collector 30; similarly, the binder coat 10 may be provided on the entire surface of the anode active material layer 20, or may be provided on a part of the surface of the anode active material layer 20, preferably on the surface of the anode active material layer 20 facing the separator. Compared with the prior art, the negative plate has the following beneficial effects: firstly, the bonding area in the bonding coating formed on the surface of the negative plate strengthens the bonding force and the bonding uniformity between the negative plate and the diaphragm in the thermal composite laminated battery, and shortens Li + The transmission path reduces the possibility of glue failure after liquid injection, each region can uniformly perform electrochemical reaction, the risk of lithium precipitation caused by non-uniform current is reduced, the safety is improved, meanwhile, the service life of a battery cell is easily prolonged due to a uniform interface, and the cycle performance of the battery is improved; secondly, the structure and the composition of the bonding coating can not obstruct Li + The electrolyte is transmitted, so that the normal use of the battery is ensured; thirdly, the gap area in the bonding coat is not provided with the bonding coat, and is equivalent to a spacing channel which can lead Li + After the battery is injected with the electrolyte, the electrolyte more effectively soaks the negative plate, so that the energy density of the battery is improved, meanwhile, the electrolyte is also beneficial to the liquid retention of the electrolyte, the cycle life of the battery can be prolonged, and the battery can be movedMechanical properties; fourthly, the flatness of the lithium ion battery can be improved when the laminated battery is prepared by thermal compounding, the thickness of the battery cell meets the requirement, or the laminated battery cell can be easily inserted into the shell, and the hardness of a long-size soft-packaged battery cell is ensured so as to prevent the battery cell from deforming; prevent the dislocation of positive negative pole piece in the long-term use, reduce safe risk.
The negative electrode sheet according to the above embodiment of the present invention will be described in detail with reference to fig. 1 to 4.
According to an embodiment of the present invention, the bonding region 11 may include: 85-95 parts of macromolecular organic matter, 1-6 parts of binder and 1-5 parts of thickening agent. The invention solves the problems that the traditional thermal compounding process is difficult to match a long-size battery core, the bonding force is not uniform, the bonding property is not strong, the glue is not easy to open and the like by arranging the bonding coating with the bonding areas and the clearance areas, wherein the main purpose of the bonding agent is to improve the bonding force and the bonding uniformity between the negative plate and the battery diaphragm, the main purpose of the thickening agent is to improve the stability and the uniformity of the bonding slurry for forming the bonding coating or the bonding areas, and the macromolecular organic matter is favorable for improving the bonding force between the negative plate and the battery diaphragm on the one hand and reducing the interface impedance between the negative plate and the battery diaphragm on the other hand; if the amount of the thickener is too small, the effect of improving the stability and uniformity of the binding slurry is insignificant, and if the amount of the thickener is too large, the energy density and electrochemical properties of the battery are also affected. According to the invention, by controlling the bonding area to be the composition, the stability of the bonding slurry, the bonding effect between the negative plate and the battery diaphragm, and the energy density and electrochemical performance of the battery can be better considered.
According to the embodiment of the present invention, the kinds of the polymer organic material, the binder and the thickener in the bonding region 11 are not particularly limited, and those skilled in the art can flexibly select them according to actual needs; preferably, the polymer organic matter can be at least one selected from carboxymethyl cellulose, polymethyl methacrylate, polyvinyl acetate, polyvinyl sulfite, polyethylene carbonate, polymethyl vinyl sulfone and polyethylene vinyl sulfone, wherein the active material layer in the negative plate has organic molecular chains, the polymer organic matter can interact with the organic molecules in the active material layer to improve the bonding force between the bonding layer and the negative plate, the battery diaphragm material also has the organic molecular chains, and the molecular chain segments of the polymer organic matter are the same or similar to the organic molecular chain segments in the diaphragm material, so that the bonding between the negative plate and the battery diaphragm is more favorably realized, the interface impedance between the negative plate and the battery diaphragm is favorably reduced, and the electrochemical performance of the battery is improved; furthermore, the binder can be at least one selected from polyvinylidene fluoride, polyethylene oxide, polyether, polymethyl methacrylate, polyacrylonitrile, sodium carboxymethylcellulose, lithium carboxymethylcellulose, polyvinylidene fluoride and polyethylene glycol, the thickener can be styrene butadiene rubber, and the binder and the thickener are the same or similar to the common binder and thickener of the negative active slurry and the common binder for gluing the battery diaphragm, so that the binder and the thickener are more favorable for realizing the binding of the negative plate and the battery diaphragm, reducing the interface impedance between the negative plate and the battery diaphragm and improving the electrochemical performance of the battery. More preferably, the bonding area, the negative electrode active material layer and the battery diaphragm are coated with the same binder, and the thickening agent adopted in the bonding area and the thickening agent adopted in the negative electrode active material layer are the same, so that the bonding effect of the negative electrode plate and the battery diaphragm and the electrochemical performance of the battery can be improved. Further, the bonding slurry for forming the bonding region may use water and/or N-methyl pyrrolidone as a solvent, preferably water, and the solid content of the bonding slurry may be 1.5 to 2wt%, thereby facilitating not only the actual production operation and controlling the raw material cost, but also the formation of the bonding region having a uniform thickness and precisely controlling the thickness of the bonding region, and preventing the energy density and electrochemical properties of the battery from being affected by an excessively large thickness of the bonding region.
According to an embodiment of the present invention, as understood with reference to FIG. 1, the thickness d (the direction of the thickness is shown as H in FIG. 1) of the bond coat 10 may be 1-10 μmI.e., the thickness of the bonding region 11 may be 1 to 10 μm, e.g., 3 μm, 5 μm, 7 μm, or 9 μm, etc., and the inventors have found that if the thickness of the bonding region is excessively small, the effect of improving the bonding force and the bonding uniformity between the negative electrode sheet and the battery separator is insignificant, and if the thickness of the bonding region is excessively large, the effect of causing Li at the bonding region portion is insignificant, and if the thickness of the bonding region is excessively large + The transmission path is obviously enlarged, the energy density of the battery is influenced, and the electrochemical performance of the battery is also influenced.
According to an embodiment of the present invention, as will be understood with reference to fig. 1 and 2, the bond coat layer 10 may include a plurality of bond regions 11 spaced apart (i.e., the plurality of bond regions 11 exhibit a discontinuous pattern of spaced apart on the anode active material layer 20), and a region where the bond regions 11 are not disposed is the gap region 12. Therefore, the bonding coating can be ensured to improve the bonding effect of the negative plate and the diaphragm, and can be helpful for the soaking and liquid retention of the electrolyte, so that the cycle performance and the service life of the battery are improved, and the safety performance of the battery in use is ensured
According to the embodiment of the invention, the bonding regions 11 can be uniformly distributed on the negative active material layer 20, so that the uniformity of the electrochemical performance of each part of the battery can be improved, potential safety hazards such as black spots and lithium precipitation can be avoided, and the cycle performance and the safety performance of the battery cell can be improved.
According to an embodiment of the present invention, as understood with reference to fig. 1 and 2, in the bond coat 10, the ratio of the total projected area of the bonding region 11 on the anode active material layer 20 to the total projected area of the gap region 12 on the anode active material layer 20 may be 25% to 100%. As can be seen from fig. 1 and 2, the bonding regions and the gap regions in the bonding coating are connected with each other, and the gap region channels formed between the bonding regions can not only make Li be Li + After the battery is injected with liquid, the electrolyte more effectively soaks the negative plate, the energy density of the battery is improved, the electrolyte is also helpful for the liquid retention of the electrolyte, the cycle performance, the service life and the dynamic performance of the battery are all improved, the safety performance of the battery in use is ensured, and the bonding area are controlled to control the liquid retention of the electrolyteThe gap area is in the proportional relation, and the energy density and the electrochemical performance of the battery are better ensured.
According to the embodiment of the present invention, the structures of the bonding regions 11 may be the same or different, and may be regular region shapes or irregular region shapes, for example, the bonding regions 11 may be rectangular, square or parallelogram, which is more beneficial for practical production operation.
According to an embodiment of the present invention, as understood with reference to fig. 1 to 4, the bonding regions 11 may be arranged in an array at intervals, for example, the bonding regions 11 may include a plurality of bonding regions 11 distributed at intervals in a length direction of the negative electrode current collector 30 (i.e., a direction indicated by L in fig. 1), a width direction of the bonding regions 11 is the same as the length direction of the negative electrode current collector 30, a width of each bonding region 11 is L1, one bonding region 11 or a plurality of bonding regions 11 distributed at intervals may be included in a width interval of one bonding region in the width direction of the negative electrode current collector 30 (i.e., a direction indicated by W in fig. 2), and a plurality of gap regions 12 may be distributed at intervals or continuously. For example, the bonding regions 11 and the gap regions 12 may be both rectangular or parallelogram (as shown in fig. 4), and the length of each bonding region 11 and each gap region 12 may be equal to the width W of the negative current collector, that is, the bonding regions 11 and the gap regions 12 may be alternately arranged along the length direction of the negative current collector 30, at this time, according to some specific examples of the present invention, the width L1 of each bonding region 11 in the length direction of the negative current collector 30 may be 0.5 to 3cm, and the width L2 of each gap region 12 in the length direction of the negative current collector 30 may be 0.5 to 3cm, thereby not only facilitating the actual production operation, but also being beneficial to ensuring the energy density and electrochemical performance of the battery; for another example, referring to fig. 3, it is understood that the bonding regions 11 may be square, a plurality of bonding regions 11 may be spaced apart from each other in a length direction of the negative electrode current collector 30 (i.e., a direction indicated by L in fig. 3), and one bonding region 11 or a plurality of bonding regions 11 may be spaced apart from each other in a width interval of each bonding region 11 in a width direction of the negative electrode current collector 30 (i.e., a direction indicated by W in fig. 3), where the plurality of gap regions 12 are in a continuous state.
According to an embodiment of the present invention, the active slurry for forming the negative electrode active material layer 20 may include 90 to 97 parts by weight of graphite, 0 to 2 parts by weight of superconducting carbon black, 1 to 3 parts by weight of carboxymethyl cellulose (CMC), and 1 to 4 parts by weight of Styrene Butadiene Rubber (SBR), wherein the graphite may be artificial graphite, wherein it is more advantageous to improve electrochemical properties of the battery using the above-described active slurry composition. Further, the thickness of the anode active material layer 20 is not particularly limited, and those skilled in the art can flexibly select according to actual needs such as the energy density of the battery, for example, the total thickness of the anode current collector 30 and the anode active material layer 20 may be 100 to 150 μm. The kind of the negative electrode current collector is not particularly limited, and may be selected flexibly by those skilled in the art according to actual needs, and may be, for example, a copper foil.
In yet another aspect of the present invention, a battery is provided. According to an embodiment of the present invention, the battery includes: the negative pole pieces, the diaphragms and the positive pole pieces are alternately stacked, the gluing diaphragms are arranged between every two adjacent negative pole pieces and the positive pole pieces, and one side of each negative pole piece, which faces the gluing diaphragms, is provided with the adhesive coatings. Compared with the prior art, the battery has the following beneficial effects: 1) The bonding region in the bonding coating formed on the surface of the negative electrode active material layer can overcome the problems of weak bonding between the negative electrode sheet and the diaphragm, and easy layering and negative electrode falling in the use process of the battery in the related technology, and shorten Li + The transmission path improves the power performance of the battery. 2) The binding power and the binding power uniformity between the negative plate and the diaphragm can be improved, so that the electrochemical performance of each part of the battery is uniform, and potential safety hazards such as black spots, lithium precipitation and the like are avoided; in the charge and discharge circulation of the battery, the temperature difference caused by different heat dissipation capacities of all parts of the battery cell can be reduced, and the circulation performance and the safety performance of the battery cell are improved. 3) The increase of the cohesive force between the negative plate and the diaphragm is convenient for stacking the unit into the aluminum shell or ensuring the strength of the soft package battery cell not to deform easily. 4) The passage formed in the gap area can enable the electrolyte to more effectively infiltrate the negative plate after the lithium ion battery is injected with the electrolyte, so that the energy density of the battery is improved; meanwhile, the electrolyte can be preserved, so that the cycle performance and the service life of the battery are improvedAnd the safety performance of the battery in use is ensured. It should be noted that the features and effects described for the negative electrode plate are also applicable to the battery, and are not described in detail herein.
According to an embodiment of the present invention, a positive electrode sheet includes a positive electrode collector and a positive electrode active material layer provided on the positive electrode collector, and an active slurry for forming the positive electrode active material layer includes: 94-98 parts of nickel-cobalt-manganese ternary positive electrode active material, 0.5-2 parts of superconducting carbon black, 0.3-2 parts of carbon nano tube and 0.5-3 parts of polyvinylidene fluoride, wherein the solid content of the active slurry is 70-72 wt%, and the active slurry composition is favorable for improving the electrochemical performance of the battery and controlling the flatness, uniformity and thickness of the positive electrode active material layer. Further, the thickness of the positive electrode active material layer and the type of the current collector of the positive electrode sheet are not particularly limited, and those skilled in the art can flexibly select the thickness according to the actual requirements such as the energy density of the battery.
According to the embodiment of the invention, the laminated structure unit of the negative plate, the diaphragm and the positive plate can be obtained by thermal compounding, for example, the positive plate, the glued diaphragm and the negative plate can be firstly laminated in a zigzag manner to obtain a stacked unit, then the stacked unit is thermally compounded, the pressurizing pressure of the thermal compounding can be 0.62-0.68 MPa, the temperature can be 80-86 ℃, the time can be 1-5 min, and the working procedures of shell filling, baking, liquid injection, formation, high-temperature standing, capacity grading, high-temperature aging, normal-temperature aging and the like are carried out after the thermal compounding is finished, so that the battery is finally prepared. If the pressurizing pressure is too low or the temperature is too low, a good bonding effect is difficult to achieve, if the temperature is too high, the molecular structure in the diaphragm or the pole piece can be damaged, the electrochemical performance, the service life and the safety of the battery are affected, if the pressure is too high, the structure of the battery can be damaged, and if the heating time is too short, the uniformity of the bonding effect and the bonding effect is difficult to ensure. In addition, it should be noted that the type of the battery is not particularly limited, and those skilled in the art can flexibly select the battery according to actual needs, for example, the battery may be a laminated battery or a wound battery, and further, for example, the battery may be a laminated lithium ion battery, etc.
In yet another aspect, the present invention provides a method of manufacturing a battery as described above. According to an embodiment of the invention, the method comprises:
(1) Coating the negative electrode active slurry on a negative electrode current collector to form a negative electrode active material layer, forming bonding regions and gap regions on the negative electrode active material layer, and alternately arranging the gap regions and the bonding regions, and/or arranging the gap regions around the bonding regions, so as to obtain a negative electrode sheet. For example, a copper foil with a thickness of 6 μm may be used as a negative current collector, and a negative active slurry may be uniformly coated on the surface of the copper foil and then cold-pressed to prepare a negative matrix, wherein the negative active slurry may be composed of 90.0 to 97.0wt% of artificial graphite, 0 to 2.0wt% of superconducting carbon black (SP), 1.0 to 3.0wt% of carboxymethyl cellulose (CMC), and 1.0 to 4.0wt% of styrene-butadiene rubber (SBR), and the thickness of the negative matrix may be 100 to 150 μm; then, using water as a solvent, mixing the water with 85.0-95.0 parts by weight of a macromolecular organic matter, 1.0-6.0 parts by weight of a binder and 1.0-5.0 parts by weight of a thickening agent to form a binding slurry, then coating the binding slurry on the surface of a negative electrode substrate by extruding, transferring, printing, spraying and the like, and then drying to form the negative electrode sheet containing the binding coating.
(2) And coating the positive active slurry on the positive current collector to form a positive active material layer so as to obtain the positive plate. For example, an aluminum foil may be used as a positive electrode current collector, and a positive electrode active material layer may be formed by uniformly coating a positive electrode active material slurry on the surface of the aluminum foil and then cold-pressing the positive electrode active material layer, so as to obtain a positive electrode sheet, wherein the positive electrode active material slurry comprises 94 to 98 parts by weight of a nickel-cobalt-manganese ternary positive electrode active material (NCM), 0.5 to 2 parts by weight of superconducting carbon black (SP), 0.3 to 2 parts by weight of Carbon Nanotubes (CNTs), and 0.5 to 3 parts by weight of polyvinylidene fluoride (PVDF), and the solid content of the active material slurry may be 70 to 72wt%.
(3) And gluing the diaphragm, and laminating the negative plate, the glued diaphragm and the positive plate to obtain a laminated unit. The lamination method is not particularly limited, and those skilled in the art can flexibly select the lamination method according to actual needs, for example, the positive electrode sheet, the adhesive-coated separator, and the negative electrode sheet can be Z-laminated to form a stacked unit.
(4) And carrying out hot-press compounding on the laminated unit so as to obtain the battery. Wherein, the pressure of the hot-pressing compounding can be 0.62-0.68 MPa, the temperature can be 80-86 ℃, and the time can be 1-5 min, it should be noted that the beneficial effects of controlling the hot-pressing compounding conditions have been explained in detail in the foregoing part, and are not repeated here.
According to the embodiment of the invention, after the hot press compounding, the method can further comprise the following steps: the battery core is subjected to the working procedures of casing, baking, liquid injection, formation, high-temperature shelving, capacity grading, high-temperature aging, normal-temperature aging and the like, so that the required battery can be finally obtained.
In summary, compared with the prior art, the method for preparing the battery according to the embodiment of the invention has a simple process, has all the technical characteristics and beneficial effects of the battery (which are not described in detail herein), and can effectively overcome the problems that the traditional thermal compounding process is difficult to match with a long-size battery core, the bonding force is not uniform, the bonding property is not strong, and the glue is not easy to open.
The following describes in detail embodiments of the present invention. The following examples are illustrative only and are not to be construed as limiting the invention. The examples do not specify particular techniques or conditions, and are performed according to techniques or conditions described in literature in the art or according to the product specification. The reagents or instruments used are conventional products which are commercially available, and are not indicated by manufacturers.
Example 1
Preparing a negative electrode sheet substrate: the copper foil with the thickness of 6 mu m is used as a negative current collector, and the surface of the copper foil is uniformly coated with negative active slurry and then subjected to cold pressing to prepare a negative matrix. Wherein the negative active slurry consists of 93.1wt% of artificial graphite, 1.6wt% of SP,2.0wt% of carboxymethyl cellulose (CMC) and 3.3wt% of styrene-butadiene rubber (SBR). The thickness of the negative electrode substrate was 130 μm.
Preparing a negative plate containing the adhesive coating: mixing 93.0wt% of carboxymethyl cellulose, 5.0wt% of polyvinylidene fluoride and 2.0wt% of styrene butadiene rubber by using water as a solvent to form slurry of a bonding coating, then coating the slurry on the surface of a negative electrode substrate in a manner of extrusion, transfer, printing, spraying and the like, and then drying to form the negative electrode sheet containing the bonding coating. The solids content of the tie coat slurry was 1.7wt%. The thickness of the bond coat was 5 μm. The bonding regions are rectangular, the length of the rectangle is equal to the width of the negative plate, the width L1 of each bonding region is 15mm, and the width L2 of each gap region is 15mm.
The schematic cross-sectional structure of the rectangular negative electrode sheet with the adhesive coating arranged in an array is shown in fig. 1.
Preparing a positive plate: and (3) adopting an aluminum foil with the thickness of 13 mu m as a positive current collector, uniformly coating positive active slurry on the surface of the aluminum foil, and then carrying out cold pressing to form a positive active substance layer, thereby preparing the positive plate. The solid content of the positive electrode active slurry was 70wt%, and the composition of the positive electrode active material layer was: NCM: SP: CNTs: PVDF =95.5wt%:1.0wt%:1.0wt%:2.5wt%. The thickness of the positive electrode sheet was 88 μm.
Preparing a battery: and performing Z-shaped lamination on the positive plate, the gluing diaphragm and the negative plate to obtain a stacking unit. The stacked units were then thermally compounded under 0.66MPa at 85 ℃ for 4min. Then carrying out the working procedures of shell filling, baking, liquid injection, formation, high-temperature shelving, capacity grading, high-temperature aging, normal-temperature aging and the like, and finally obtaining the lithium ion battery.
Example 2
The lithium ion battery is prepared in the same manner as in example 1, except that the bonding regions in the bonding coating are squares, and the squares are arranged in a 3 × n (n is a positive integer) array, as shown in fig. 3, the width of the negative electrode sheet is 94mm, the width L1 of each bonding region is 15mm, and the width L2 of the gap between two adjacent bonding regions in the length direction of the negative electrode sheet is 15mm.
Example 3
The lithium ion battery was prepared as in example 1, except that the bonding regions in the bond coat were parallelogram shaped, as shown in fig. 4.
Example 4
The lithium ion battery was fabricated in the same manner as in example 1, except that the ratio of the total projected area of the bonding region on the negative electrode active material layer to the total projected area of the gap region on the negative electrode active material layer was 50%.
Example 5
The lithium ion battery was fabricated in the same manner as in example 1, except that the ratio of the total projected area of the bonding region on the negative electrode active material layer to the total projected area of the gap region on the negative electrode active material layer was 25%.
Comparative example 1
Otherwise, the scheme is the same as that of example 1, but the negative plate does not contain the binding coating.
Preparing a negative plate: the copper foil with the thickness of 6 mu m is used as a negative current collector, and negative active slurry is uniformly coated on the surface of the copper foil and then cold-pressed to prepare the negative plate. Wherein the negative active slurry consists of 93.1wt% of artificial graphite, 1.6wt% of SP,2.0wt% of carboxymethyl cellulose (CMC) and 3.3wt% of styrene-butadiene rubber (SBR). The thickness of the negative electrode sheet was 130 μm.
Preparing a positive plate: and (3) adopting an aluminum foil with the thickness of 13 mu m as a positive electrode current collector, uniformly coating the positive electrode active slurry on the surface of the aluminum foil, and then carrying out cold pressing to form a positive electrode active substance layer, thereby preparing the positive electrode plate. The solid content of the positive electrode active slurry was 70wt%, and the composition of the positive electrode active material layer was: NCM: SP: CNTs: PVDF =95.5wt%:1.0wt%:1.0wt%:2.5wt%. The thickness of the positive electrode sheet was 88 μm.
Preparing a battery: and performing Z-shaped lamination on the positive plate, the gluing diaphragm and the negative plate to obtain a stacking unit. The stacked units were then thermally compounded under 0.66MPa at 85 ℃ for 4min. Then carrying out the working procedures of shell entering, baking, liquid injection, formation, high-temperature shelving, capacity grading, high-temperature aging, normal-temperature aging and the like to finally prepare the lithium ion battery.
Comparative example 2
The other protocol was the same as comparative example 1, but the membrane used a ceramic coated membrane instead of a rubberized membrane.
Preparing a negative plate: the copper foil with the thickness of 6 mu m is used as a negative current collector, and negative active slurry is uniformly coated on the surface of the copper foil and then cold-pressed to prepare the negative plate. Wherein the negative active slurry consists of 93.1wt% of artificial graphite, 1.6wt% of SP,2.0wt% of carboxymethyl cellulose (CMC) and 3.3wt% of styrene-butadiene rubber (SBR). The thickness of the negative electrode sheet was 130 μm.
Preparing a positive plate: and (3) adopting an aluminum foil with the thickness of 13 mu m as a positive current collector, uniformly coating positive active slurry on the surface of the aluminum foil, and then carrying out cold pressing to form a positive active substance layer, thereby preparing the positive plate. The solid content of the positive electrode active slurry was 70wt%, and the composition of the positive electrode active material layer was: NCM: SP: CNTs: PVDF =95.5wt%:1.0wt%:1.0wt%:2.5wt%. The thickness of the positive electrode sheet was 88 μm.
Preparing a battery: and performing Z-shaped lamination on the positive plate, the ceramic-coated diaphragm and the negative plate to obtain a stacking unit. The stacked units were then thermally compounded under 0.66MPa at 85 ℃ for 4min. Then carrying out the working procedures of shell filling, baking, liquid injection, formation, high-temperature shelving, capacity grading, high-temperature aging, normal-temperature aging and the like, and finally obtaining the lithium ion battery.
The batteries obtained in examples 1 to 5 and comparative examples 1 to 2 were tested:
the test results are detailed in table 1. The method for testing the cycle performance of the battery comprises the following steps: standing the battery for 30min at 25 +/-2 ℃, charging to 4.35V at a constant current of 1C, and then charging at a constant voltage until the current of 0.05C is cut off; standing for 30min; then discharging to 2.75V by using 1C constant current; the cycle is 100 cycles.
TABLE 1 test results of batteries of examples 1-5 and comparative examples 1-2
Results and conclusions:
the test results in table 1 show that the retention rate of the battery core circulation capacity is highest after the negative electrode is coated with the bonding coating and then thermally compounded with the gluing diaphragm, no glue is broken after the battery core is circularly disassembled, and the bonding force between the diaphragm and the negative electrode is still obvious. The adhesive is coated on the surface of the negative electrode, so that the adhesive is favorable for improving the adhesive force between the diaphragm and the negative electrode, and the adhesive area and the gap area are distributed at intervals, so that the electrolyte is favorably soaked and preserved, the cycle performance and the service life of the battery are improved, and the safety performance of the battery in use is ensured. In addition, as can be seen from examples 1 to 5, when the ratio of the total projected area of the bonding region on the anode active material layer to the total projected area of the gap region on the anode active material layer was increased from 25% to 100%, the bonding force was increased from 2.6N/m to 4N/m, and the bonding force between the separator and the anode was remarkably enhanced. However, the battery capacity retention rate does not decrease with the increase of the area ratio, and when the area ratio is 50%, the battery capacity retention rate is the highest, and is 99.7%.
In the description herein, references to the description of the term "one embodiment," "some embodiments," "an example," "a specific example," or "some examples," etc., mean that a particular feature, structure, material, or characteristic described in connection with the embodiment or example is included in at least one embodiment or example of the invention. In this specification, the schematic representations of the terms used above are not necessarily intended to refer to the same embodiment or example. Furthermore, the particular features, structures, materials, or characteristics described may be combined in any suitable manner in any one or more embodiments or examples. Moreover, various embodiments or examples and features of various embodiments or examples described in this specification can be combined and combined by one skilled in the art without being mutually inconsistent.
Although embodiments of the present invention have been shown and described above, it is understood that the above embodiments are exemplary and should not be construed as limiting the present invention, and that variations, modifications, substitutions and alterations can be made to the above embodiments by those of ordinary skill in the art within the scope of the present invention.
Claims (10)
1. A negative electrode sheet, comprising:
a negative current collector;
a negative electrode active material layer provided on the negative electrode current collector;
a binder coating provided on at least a part of a surface of the anode active material layer, the binder coating including a binder region and a gap region alternately provided with the binder region and/or provided around the binder region.
2. The negative electrode sheet of claim 1, wherein the bonding region comprises: 85-95 parts of macromolecular organic matter, 1-6 parts of binder and 1-5 parts of thickening agent.
3. The negative electrode sheet according to claim 2, wherein at least one of the following conditions is satisfied:
the high molecular organic matter comprises at least one selected from carboxymethyl cellulose, polymethyl methacrylate, polyvinyl acetate, polyvinyl ethylene sulfite, polyethylene ethylene carbonate, polymethyl vinyl sulfone and polyethylene vinyl sulfone;
the binder is at least one selected from polyvinylidene fluoride, polyethylene oxide, polyether, polymethyl methacrylate, polyacrylonitrile, sodium carboxymethyl cellulose, lithium carboxymethyl cellulose, polyvinylidene fluoride and polyethylene glycol;
the thickening agent is styrene butadiene rubber;
the bonding slurry for forming the bonding area takes water and/or N-methyl pyrrolidone as a solvent, and the solid content of the bonding slurry is 1.5-2 wt%.
4. Negative electrode sheet according to any one of claims 1 to 3, characterized in that at least one of the following conditions is satisfied:
the thickness of the bonding coating is 1-10 mu m;
the bonding coating comprises a plurality of bonding areas distributed at intervals, and the area where the bonding areas are not arranged is the gap area;
the ratio of the total projected area of the bonding region on the negative electrode active material layer to the total projected area of the gap region on the negative electrode active material layer is 25% to 100%.
5. The negative electrode sheet according to claim 4, wherein the bonding regions are arranged in an array at intervals; and/or the presence of a gas in the atmosphere,
the width direction of the bonding area is the same as the length direction of the negative current collector, and the width of each bonding area is 0.5-3 cm.
6. The negative electrode sheet according to any one of claims 1 to 3, wherein the active slurry for forming the negative electrode active material layer comprises 90 to 97 parts by weight of graphite, 0 to 2 parts by weight of superconducting carbon black, 1 to 3 parts by weight of carboxymethyl cellulose, and 1 to 4 parts by weight of styrene-butadiene rubber; and/or the presence of a gas in the atmosphere,
the total thickness of the negative electrode current collector and the negative electrode active material layer is 100 to 150 [ mu ] m.
7. A battery, comprising: the negative electrode plate, the separator and the positive electrode plate as claimed in any one of claims 1 to 6, wherein the negative electrode plate and the positive electrode plate are alternately stacked, a gummed separator is arranged between two adjacent negative electrode plates and the positive electrode plate, and the side of the negative electrode plate facing the gummed separator is provided with the adhesive coating.
8. The battery according to claim 7, wherein the positive electrode sheet includes a positive electrode collector and a positive electrode active material layer provided on the positive electrode collector, and the active slurry for forming the positive electrode active material layer includes: 94-98 parts of nickel-cobalt-manganese ternary positive electrode active material, 0.5-2 parts of superconducting carbon black, 0.3-2 parts of carbon nano tube and 0.5-3 parts of polyvinylidene fluoride, wherein the solid content of the active slurry is 70-72 wt%; and/or the presence of a gas in the gas,
the negative plate adopts copper foil as a negative current collector, and the positive plate adopts aluminum foil as a positive current collector.
9. A method of making the battery of claim 7 or 8, comprising:
(1) Coating negative active slurry on a negative current collector to form a negative active material layer, and forming a bonding area and a gap area on the negative active material layer so as to obtain a negative plate;
(2) Coating positive active slurry on a positive current collector to form a positive active substance layer so as to obtain a positive plate;
(3) Gluing the diaphragm, and laminating the negative plate, the glued diaphragm and the positive plate to obtain a laminated unit;
(4) And carrying out hot-press compounding on the lamination unit so as to obtain the battery.
10. The method according to claim 9, wherein the pressure of the hot-press compounding is 0.62-0.68 MPa, the temperature is 80-86 ℃, and the time is 1-5 min; and/or the presence of a gas in the atmosphere,
the hot-pressing compounding process further comprises the following steps: the method comprises the working procedures of cell shelling, baking, liquid injection, formation, high-temperature shelving, capacity grading, high-temperature aging and normal-temperature aging.
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Cited By (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| WO2024090859A1 (en) * | 2022-10-28 | 2024-05-02 | 주식회사 엘지화학 | Integrated electrode/separator for lithium secondary battery, and lithium secondary battery comprising same |
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Cited By (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| WO2024090859A1 (en) * | 2022-10-28 | 2024-05-02 | 주식회사 엘지화학 | Integrated electrode/separator for lithium secondary battery, and lithium secondary battery comprising same |
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