CN113903921A - Positive plate and battery - Google Patents
Positive plate and battery Download PDFInfo
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- CN113903921A CN113903921A CN202111367463.8A CN202111367463A CN113903921A CN 113903921 A CN113903921 A CN 113903921A CN 202111367463 A CN202111367463 A CN 202111367463A CN 113903921 A CN113903921 A CN 113903921A
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- positive electrode
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- electrode sheet
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- 238000000576 coating method Methods 0.000 claims abstract description 82
- 239000011248 coating agent Substances 0.000 claims abstract description 76
- 239000011888 foil Substances 0.000 claims abstract description 61
- 239000011241 protective layer Substances 0.000 claims abstract description 51
- 239000011247 coating layer Substances 0.000 claims description 39
- WHXSMMKQMYFTQS-UHFFFAOYSA-N Lithium Chemical compound [Li] WHXSMMKQMYFTQS-UHFFFAOYSA-N 0.000 abstract description 41
- 229910052744 lithium Inorganic materials 0.000 abstract description 41
- HBBGRARXTFLTSG-UHFFFAOYSA-N Lithium ion Chemical compound [Li+] HBBGRARXTFLTSG-UHFFFAOYSA-N 0.000 abstract description 15
- 229910001416 lithium ion Inorganic materials 0.000 abstract description 15
- 238000000926 separation method Methods 0.000 abstract 2
- 238000001556 precipitation Methods 0.000 description 13
- 239000010410 layer Substances 0.000 description 11
- 238000000034 method Methods 0.000 description 11
- SECXISVLQFMRJM-UHFFFAOYSA-N N-Methylpyrrolidone Chemical compound CN1CCCC1=O SECXISVLQFMRJM-UHFFFAOYSA-N 0.000 description 10
- XAGFODPZIPBFFR-UHFFFAOYSA-N aluminium Chemical compound [Al] XAGFODPZIPBFFR-UHFFFAOYSA-N 0.000 description 10
- 229910052782 aluminium Inorganic materials 0.000 description 10
- 239000002002 slurry Substances 0.000 description 8
- 238000003466 welding Methods 0.000 description 8
- 238000001035 drying Methods 0.000 description 7
- 239000000853 adhesive Substances 0.000 description 6
- 230000001070 adhesive effect Effects 0.000 description 6
- 239000000463 material Substances 0.000 description 6
- 238000004140 cleaning Methods 0.000 description 5
- 238000005520 cutting process Methods 0.000 description 5
- 230000008021 deposition Effects 0.000 description 5
- 239000002033 PVDF binder Substances 0.000 description 4
- 239000006258 conductive agent Substances 0.000 description 4
- 239000011267 electrode slurry Substances 0.000 description 4
- 229920002981 polyvinylidene fluoride Polymers 0.000 description 4
- 239000007787 solid Substances 0.000 description 4
- 239000002904 solvent Substances 0.000 description 4
- 238000003756 stirring Methods 0.000 description 4
- 238000005406 washing Methods 0.000 description 4
- 238000004804 winding Methods 0.000 description 4
- 230000000052 comparative effect Effects 0.000 description 3
- 230000000694 effects Effects 0.000 description 3
- 230000001681 protective effect Effects 0.000 description 3
- 239000011149 active material Substances 0.000 description 2
- 238000004519 manufacturing process Methods 0.000 description 2
- 230000002035 prolonged effect Effects 0.000 description 2
- 238000012360 testing method Methods 0.000 description 2
- 230000009286 beneficial effect Effects 0.000 description 1
- 230000015572 biosynthetic process Effects 0.000 description 1
- QHGJSLXSVXVKHZ-UHFFFAOYSA-N dilithium;dioxido(dioxo)manganese Chemical compound [Li+].[Li+].[O-][Mn]([O-])(=O)=O QHGJSLXSVXVKHZ-UHFFFAOYSA-N 0.000 description 1
- 238000007599 discharging Methods 0.000 description 1
- 239000003792 electrolyte Substances 0.000 description 1
- 238000005516 engineering process Methods 0.000 description 1
- 239000003292 glue Substances 0.000 description 1
- 238000007731 hot pressing Methods 0.000 description 1
- GELKBWJHTRAYNV-UHFFFAOYSA-K lithium iron phosphate Chemical compound [Li+].[Fe+2].[O-]P([O-])([O-])=O GELKBWJHTRAYNV-UHFFFAOYSA-K 0.000 description 1
- 238000012986 modification Methods 0.000 description 1
- 230000004048 modification Effects 0.000 description 1
- 238000004806 packaging method and process Methods 0.000 description 1
- 230000000149 penetrating effect Effects 0.000 description 1
- 230000035515 penetration Effects 0.000 description 1
- 239000002985 plastic film Substances 0.000 description 1
- 229920006255 plastic film Polymers 0.000 description 1
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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
- H01M4/64—Carriers or collectors
- H01M4/66—Selection of materials
- H01M4/665—Composites
- H01M4/667—Composites in the form of layers, e.g. coatings
-
- 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
- H01M4/00—Electrodes
- H01M4/02—Electrodes composed of, or comprising, active material
- H01M4/64—Carriers or collectors
- H01M4/70—Carriers or collectors characterised by shape or form
-
- 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
-
- Y—GENERAL TAGGING OF NEW TECHNOLOGICAL DEVELOPMENTS; GENERAL TAGGING OF CROSS-SECTIONAL TECHNOLOGIES SPANNING OVER SEVERAL SECTIONS OF THE IPC; TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS
- Y02—TECHNOLOGIES OR APPLICATIONS FOR MITIGATION OR ADAPTATION AGAINST CLIMATE CHANGE
- Y02E—REDUCTION OF GREENHOUSE GAS [GHG] EMISSIONS, RELATED TO ENERGY GENERATION, TRANSMISSION OR DISTRIBUTION
- Y02E60/00—Enabling technologies; Technologies with a potential or indirect contribution to GHG emissions mitigation
- Y02E60/10—Energy storage using batteries
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- Chemical & Material Sciences (AREA)
- Engineering & Computer Science (AREA)
- Chemical Kinetics & Catalysis (AREA)
- Electrochemistry (AREA)
- General Chemical & Material Sciences (AREA)
- Materials Engineering (AREA)
- Manufacturing & Machinery (AREA)
- Composite Materials (AREA)
- Secondary Cells (AREA)
- Battery Electrode And Active Subsutance (AREA)
Abstract
The invention provides a positive plate and a battery, wherein the positive plate comprises: the current collector comprises a current collector, a first coating, a second coating and a protective layer, wherein the first coating is coated on a first area of the surface of the current collector, the second coating is coated on a second area of the surface of the current collector, the first area is adjacent to the second area, and a hollow foil area is arranged between the first coating and the second coating; the protective layer covers the surface of the second coating and the empty foil regions. According to the embodiment of the invention, the hollow foil area is arranged between the first coating and the second coating, so that the difficulty of lithium ion separation from the first coating is increased, and the lithium ion released by the first coating at the edge of the protective layer is reduced, thereby reducing the possibility of lithium separation at the position of the negative plate corresponding to the edge of the protective layer, reducing the possibility of battery cell deformation, and prolonging the service life of the battery.
Description
Technical Field
The invention relates to the technical field of batteries, in particular to a positive plate and a battery.
Background
The lithium battery is a battery technology widely applied to mobile electronic equipment, and has the characteristics of high energy density, long service life and the like. With the increasing demand of the market for energy density and charging speed of lithium batteries, the performance of lithium batteries is required to be further improved. In the prior art, the situation of lithium precipitation easily occurs at the edge of the gummed paper pasted on the negative electrode tab corresponding to the positive electrode plate and the edge of the ending gummed paper, which leads to the occurrence of the situation of failure and deformation of the battery cell, so that the service life of the lithium battery is relatively short.
Therefore, the problem that the service life of the lithium battery is short exists in the prior art.
Disclosure of Invention
The embodiment of the invention provides a positive plate and a battery, which aim to solve the problem that the service life of a lithium battery is short in the prior art.
In order to achieve the above object, an embodiment of the present invention provides a positive electrode sheet, including: a current collector, a first coating, a second coating, and a protective layer, wherein,
the first coating is coated on a first area of the surface of the current collector, the second coating is coated on a second area of the surface of the current collector, the first area is adjacent to the second area, and a hollow foil area is arranged between the first coating and the second coating;
the protective layer covers a surface of the second coating and the empty foil region.
As an alternative embodiment, the protective layer also covers the edge of the first coating layer close to the second coating layer, the first edge of the protective layer is positioned on the surface of the first coating layer, and the distance between the first edge of the protective layer and the edge of the first coating layer close to the second coating layer is 0-3 mm.
As an alternative embodiment, the empty foil region includes at least one sub empty foil region, and the sub empty foil regions communicate with two opposite ends of the current collector in the width direction of the current collector.
As an alternative embodiment, the width of the sub-empty foil area is 0.1-3 mm.
As an alternative embodiment, the shape of the sub-empty foil area is a wavy line type, a broken line type or a straight line type.
As an alternative embodiment, the first coating layer includes a notch formed by recessing inward from a first edge thereof, and the notch is the empty foil region;
the notch is disposed around the second coating.
As an alternative embodiment, the width of the recess is 0.1-3 mm.
As an alternative embodiment, the shape of the notch is U-shaped, mouth-shaped, X-shaped, Z-shaped or field-shaped.
The embodiment of the invention also provides a battery, which comprises the positive plate, wherein the protective layer is positioned at the ending part of the positive plate.
The embodiment of the invention also provides a battery, which comprises the positive plate, a negative plate and a negative pole lug fixed on the surface of the negative plate, wherein the protective layer is positioned at the position of the positive plate corresponding to the negative pole lug. One of the above technical solutions has the following advantages or beneficial effects:
in the embodiment of the invention, the hollow foil area is arranged between the first coating and the second coating, so that the difficulty of the lithium ions in precipitation from the first coating is increased, and the lithium ions released by the first coating at the edge of the protective layer are reduced, thereby reducing the possibility of lithium precipitation at the position of the negative plate corresponding to the edge of the protective layer, reducing the possibility of deformation of a battery core and prolonging the service life of the lithium battery.
Drawings
To more clearly illustrate the technical solutions of the embodiments of the present invention, the drawings used in the description of the embodiments of the present invention will be briefly introduced below, and it is obvious that the drawings in the following description are only some embodiments of the present invention, and it is obvious for those skilled in the art to obtain other drawings based on these drawings without inventive labor.
Fig. 1 is a plan view of a structure of a positive electrode tab according to an embodiment of the present invention;
fig. 2 is a side view of a structure of a positive electrode tab according to an embodiment of the present invention;
fig. 3 is a plan view of the structure of a positive electrode sheet of the prior art;
fig. 4 is a side view of the structure of another positive electrode sheet of the prior art;
fig. 5 is a plan view of a structure of another positive electrode tab provided by an embodiment of the present invention;
fig. 6 is a side view of the structure of another positive electrode tab provided by the embodiment of the invention;
fig. 7 is a plan view of the structure of another positive electrode sheet of the prior art;
fig. 8 is a side view of the structure of another positive electrode sheet of the prior art.
Detailed Description
The technical solutions in the embodiments of the present invention will be clearly and completely described below with reference to the drawings in the embodiments of the present invention, and it is obvious that the described embodiments are some, but not all embodiments of the present application. All other embodiments, which can be derived by a person skilled in the art from the embodiments given herein without making any creative effort, shall fall within the protection scope of the present application.
The terms first, second and the like in the description and in the claims of the present application are used for distinguishing between similar elements and not necessarily for describing a particular sequential or chronological order. It will be appreciated that the data so used may be interchanged under appropriate circumstances such that embodiments of the application may be practiced otherwise than as specifically illustrated or described herein, and that the objects identified as "first" or "second" are generally a generic term and do not limit the number of objects, e.g., the first object may be one or more.
Referring to fig. 1 and 2, fig. 1 and 2 are plan views of a structure of a positive electrode plate according to an embodiment of the present invention, including: current collector 10, first coating 20, second coating 30, and protective layer 40, wherein,
the first coating 20 is coated on a first area of the surface of the current collector 10, the second coating 30 is coated on a second area of the surface of the current collector 10, the first area and the second area are adjacent, and an empty foil area is arranged between the first coating 20 and the second coating 30;
the protective layer 40 covers the surface of the second coating 30 and the empty foil areas.
In one specific example, the material of the current collector 10 may be aluminum foil; the shape of current collector 10 may be rectangular. In yet another specific example, the protective layer may be, for example, a gummed paper.
In one particular example, the first coating layer and the second coating layer include an active material including at least one of lithium cobaltate, lithium manganate, lithium iron phosphate, and a ternary material. In a further specific example, a coating layer may be formed on the current collector 10 by coating, and then a hollow foil region and a first coating layer and a second coating layer located at both sides of the hollow foil region are formed by cleaning or the like.
In a specific example, the surface of the current collector 10 includes a first surface and a second surface, and a first area and a second area are disposed on each of the first surface and the second surface of the current collector 10, the first area is provided with the first coating 20, and the second area is provided with the second coating 30. The projection of the first area of the first face of the current collector 10 on the current collector 10 may be overlapped or not overlapped with the projection of the first area of the second face of the current collector 10 on the current collector 10; the projection of the second area of the first surface of the current collector 10 on the current collector 10 and the projection of the second area of the second surface of the current collector 10 on the current collector 10 may be overlapped or not overlapped, that is, the projection of the protection layer and the empty foil area of the first surface of the current collector on the current collector 10 and the projection of the protection layer and the empty foil area of the second surface of the current collector 10 on the current collector 10 may be overlapped or not overlapped, respectively. In this embodiment, by providing the empty foil region between the first coating layer 20 and the second coating layer 30, it is possible to effectively prevent lithium ions in the second coating layer covered by the protective layer from being transported to the first coating layer uncovered by the protective layer and being released from the first coating layer, thereby reducing lithium ions released by the first coating layer at the edge of the protective layer, that is, reducing lithium ions received at a position corresponding to the protective layer on the negative electrode sheet in the battery loaded with the positive electrode sheet, and reducing the possibility of lithium deposition at a position corresponding to the edge of the protective layer on the negative electrode sheet; meanwhile, the empty foil area is covered with the protective layer, so that the thickness of the battery cell is ensured not to change on the premise of avoiding the short circuit of the battery, the possibility of deformation of the battery cell is reduced, and the service life of the lithium battery is prolonged.
The structure of the positive plate in the prior art is shown in fig. 3 and 4, and includes a current collector, a first coating 30, a second coating 20, and a protective layer 40 covering the second coating 20, where the first coating 30 and the second coating 20 are connected, the first coating, the second coating, and the protective layer are located at the end of the positive plate, and the second coating at the edge of the protective layer 40 releases lithium ions to the first coating, which causes the first coating at the edge of the protective layer 40 to release more lithium ions, so that a problem of lithium precipitation occurs at a position of the negative plate corresponding to the end of the positive plate.
In the embodiment provided by the present invention, the first area is located at the ending of the current collector 10, the second area is located at a side of the first area close to the ending, and the protection layer covers the empty foil area, the second coating layer and the current collector at a side of the second area away from the first area. Compared with the scheme in the prior art, the embodiment has the advantages that the empty foil area is arranged, the passage for transmitting lithium ions from the second coating to the first coating is cut off, the lithium ions released by the first coating at the edge of the protective layer are reduced, namely, the lithium ions received by the position, corresponding to the protective layer, on the negative electrode plate in the battery loaded with the positive electrode plate are reduced, and the occurrence of lithium precipitation can be effectively reduced.
It can be understood that, in another embodiment provided by the present invention, a first coating layer, a second coating layer, a blank foil area and a protective layer located between the first coating layer and the second coating layer are disposed on both the front side and the back side of the ending of the current collector of the positive plate, wherein projections of the protective layer and the blank foil area on the front side of the current collector do not overlap projections of the protective layer and the blank foil area on the back side of the current collector, so as to cut off a path through which the second coating layer on the front side and the back side of the current collector transmits lithium ions to the first coating layer, reduce lithium ions released by the first coating layer on the edge of the protective layer on the front side and the back side, and further reduce the possibility of lithium deposition on the corresponding position of the edge of the protective layer on the front side and the back side of the negative plate.
In addition, the empty foil area may also be located at a position of the positive electrode tab corresponding to the negative electrode tab, as shown in fig. 5 and 6, compared to the position of the negative electrode tab of the prior art solution without the empty foil area as shown in fig. 7 and 8, the embodiment as shown in fig. 5 and 6 may reduce the problem of lithium deposition at the edge of the negative electrode tab by providing the empty foil area.
In specific implementation, the negative electrode tab can be arranged at the end part of the negative electrode plate; in another specific example, the negative electrode tab may also be disposed at a middle position of the negative electrode sheet, and both sides of the negative electrode tab are adjacent to the active material layer of the negative electrode sheet.
As an alternative embodiment, the protective layer 40 also covers the edge of the first coating layer 20 close to the second coating layer 30, the first edge of the protective layer 40 is positioned on the surface of the first coating layer 20, and the first edge of the protective layer 40 is 0-3mm away from the edge of the first coating layer 20 close to the second coating layer 30.
In this embodiment, the empty foil regions are covered by a protective layer 40 to avoid cell shorting problems. In order to prevent the situation that the battery short circuit does not occur due to the fact that the protective layer 40 is not tightly adhered in the process and the using process, the first edge of the protective layer 40 covers the edge of the second coating 30, so that the empty foil area can be completely covered by the protective layer 40 without exposing the foil, the yield of products is improved, and the service life of the products is prolonged.
As an alternative embodiment, the empty foil region includes at least one sub empty foil region, and the sub empty foil regions communicate with two opposite ends of the current collector 10 in the width direction of the current collector. In one particular example, the empty foil region comprises a plurality of sub-empty foil regions arranged side by side.
In this embodiment, the positive electrode sheet needs to have a plurality of protective layers 40 attached thereto, for example, at a negative electrode tab corresponding position, a positive electrode sheet terminating position, and the like. The protective layer 40 is mainly used for preventing the short circuit problem caused by the contact of a negative electrode tab and a positive electrode plate or the contact of a diaphragm and the negative electrode plate caused by the penetration of burrs at the ending position of the positive electrode plate. In the embodiment of the invention, different sub-empty foil areas are arranged aiming at different positions to solve the problem of lithium precipitation, so that the application range of the embodiment is improved.
For the protection layer 40 located at the ending position of the positive plate, in this embodiment, at least one sub-empty foil area is arranged at the ending position, only one side of the second coating covered by the protection layer is provided with the first coating, and the empty foil area can cut off the passage between the second coating and other coatings (such as the first coating) which are not covered by the protection layer, so that the situation of lithium precipitation can be effectively prevented.
In another embodiment, the protection layer 40 is located at a position of the positive plate corresponding to the negative electrode tab, and since the protection layer 40 entirely covers the surface of the positive plate, the first coatings are disposed on both sides of the second coating covered by the protection layer, and the second coating covered by the protection layer 40 is separated from the first coatings on both sides by disposing two sub-empty foil regions, thereby effectively preventing the occurrence of a lithium precipitation situation.
As an alternative embodiment, the width of the sub-empty foil areas is 0.1-3 mm.
In this embodiment, the sub-empty foil region needs to be set to a certain width, so as to avoid the problem that the lithium deposition cannot be effectively prevented due to too small width or the influence of too large width on the energy density of the battery is avoided. The width of the sub-empty foil zone was experimentally selected to be 0.1-3 mm.
As an alternative embodiment, the shape of the sub-empty foil area is wavy line type, zigzag line type or straight line type.
In this embodiment, the sub-empty foil regions can be set to different shapes according to actual requirements to meet different use environments and production environments.
As an alternative embodiment, the first coating layer 20 includes a recess 50 formed to be recessed inward from a first side thereof, the recess 50 being a hollow foil region, the recess 50 being disposed around the second coating layer 30.
In the example shown in fig. 5 and 6, the notch 50 is located at a position of the positive electrode tab corresponding to the position of the negative electrode tab, the notch being matched with the position of the negative electrode tab, and the notch includes two through holes penetrating through one side surface of the first coating layer 20. The left side, the right side and the bottom side of the second coating are provided with the first coatings 20, and the second coating is separated from the first coatings on the left side and the right side of the second coating by arranging the empty foil areas surrounding the second coating 30 so as to cut off a path for the second coating to transmit lithium ions to the first coatings on the left side and the right side, and reduce the possibility of lithium precipitation of a negative electrode tab; moreover, the size of notch and the size phase-match of negative pole utmost point ear to inject the cutting off region of second coating and first coating, avoid having the battery capacity and the charge rate of the battery that loads this positive plate and cause the influence, can realize reducing the marginal area condition of analyzing lithium of negative pole utmost point ear under the prerequisite of the charge-discharge performance of battery.
As an alternative embodiment, the width of the notch 50 is 0.1-3 mm.
In this embodiment, the notch 50 needs to have a certain width to avoid the problem that the lithium deposition cannot be effectively prevented due to an excessively small width or the battery energy density is not affected due to an excessively large width. The width of the sub-empty foil zone was experimentally selected to be 0.1-3 mm.
As an alternative embodiment, the shape of the notch 50 is U-shaped, mouth-shaped, X-shaped, Z-shaped, or field-shaped.
In this embodiment, the recess 50 may be designed in various shapes, such as a U-shape, a mouth-shape, an X-shape, a Z-shape, or a field-shape, according to the difference between the use environment and the production environment. The differently shaped recesses 50 may simultaneously achieve the effect of preventing lithium precipitation.
The positive electrode sheet of this example can be obtained by carrying out the following steps:
example 1, a first lithium battery positive electrode sheet was prepared: adding a lithium cobaltate positive main material, a conductive agent and polyvinylidene fluoride into a stirring tank according to a mass ratio of 97:1.5:1.5, then adding an NMP (N-methyl-2-pyrrolidone) solvent to prepare a positive slurry, wherein the solid content of the positive slurry is 70-75%, coating the slurry on an aluminum foil 10 by using a coating machine, drying at 120 ℃ for 8 hours, cutting into small strips, cleaning by using a scraper, washing out the welding position of a positive tab, the tail adhesive paper and the inner side edge of two negative tab protective adhesive papers by 0.1mm, compacting by using a roller press, and welding an aluminum tab to obtain a first lithium battery positive plate;
example 2, a second lithium battery positive electrode sheet was prepared: adding a lithium cobaltate positive main material, a conductive agent and polyvinylidene fluoride into a stirring tank according to a mass ratio of 97:1.5:1.5, adding an NMP solvent to prepare a positive slurry, wherein the solid content of the positive slurry is 70-75%, coating the slurry on an aluminum foil 10 by using a coating machine, drying for 8 hours at the temperature of 120 ℃, cutting into small strips after drying, cleaning by using a scraper, washing out a positive tab welding position, a piece of tail-ending adhesive paper and the inner side edges of two pieces of negative tab protective adhesive paper by 1mm, compacting by using a roller press, and welding an aluminum tab to obtain a second lithium battery positive plate;
example 3, a third lithium battery positive electrode sheet was prepared: adding lithium cobaltate positive electrode main material, a conductive agent and polyvinylidene fluoride into a stirring tank according to the mass ratio of 97:1.5:1.5, then adding NMP solvent to prepare positive electrode slurry, wherein the solid content of the positive electrode slurry is 70-75%, then coating the slurry on an aluminum foil 10 by using a coating machine, drying for 8h at the temperature of 120 ℃, cutting into small strips after drying, cleaning by using a scraper, washing out the welding position of a positive electrode tab, the tail-ending adhesive paper and the inner side edges of two negative electrode tab protective adhesive papers by 2mm, then compacting by using a roller press, and welding an aluminum tab to obtain a third lithium battery positive electrode sheet.
Comparative example 1, a comparative positive electrode sheet was prepared: adding lithium cobaltate positive electrode main material, a conductive agent and polyvinylidene fluoride into a stirring tank according to the mass ratio of 97:1.5:1.5, then adding an NMP solvent to prepare positive electrode slurry, wherein the solid content of the positive electrode slurry is 70-75%, then coating the slurry on an aluminum foil 10 by using a coating machine, drying for 8 hours at the temperature of 120 ℃, cutting into small strips after drying, cleaning by using a scraper, washing out the welding position of a positive electrode tab, then compacting by using a roller press, welding an aluminum tab, pasting tab glue and negative electrode tab protection gummed paper, and obtaining a comparative positive electrode sheet.
And assembling the obtained first lithium battery positive plate, the second lithium battery positive plate, the third lithium battery positive plate and the comparison positive plate with the negative plates of the same type, winding the positive plates and the diaphragms together to form a winding core, packaging the winding core with an aluminum plastic film, baking the winding core to remove moisture, injecting electrolyte, and forming by adopting a hot-pressing formation process to obtain different battery cores.
The method comprises the following steps of performing 0.2C/0.2C charging and discharging test on the capacity of a battery cell on the battery cells of different embodiments at 25 ℃, calculating the energy density of the battery according to the capacity, voltage, thickness, width and height, testing the cycle performance of 3C/1C at 25 ℃, disassembling the battery at different cycle times to confirm the lithium precipitation condition at the position of a battery tab, and obtaining the following disassembly result:
as can be seen from table 1, the battery cell prepared by the method in the patent can significantly improve the lithium precipitation condition of the battery cell, and improve the battery cell deformation and expansion caused by lithium precipitation of the battery cell, thereby improving the cycle life of the battery cell.
The embodiment of the application further provides a battery, which comprises the positive plate, and the protective layer is located at the ending part of the positive plate.
It should be noted that, the implementation manner of the above-mentioned positive plate embodiment is also applicable to this battery embodiment, and can achieve the same technical effect, and details are not described herein again.
The embodiment of the application further provides a battery, which comprises the positive plate, the negative plate and a tab fixed on the surface of the negative plate, wherein the protective layer is located on the position of the positive plate corresponding to the tab of the negative plate.
It should be noted that, the implementation manner of the above-mentioned positive plate embodiment is also applicable to this battery embodiment, and can achieve the same technical effect, and details are not described herein again.
It should be noted that, in this document, the terms "comprises," "comprising," or any other variation thereof, are intended to cover a non-exclusive inclusion, such that a process, method, article, or apparatus that comprises a list of elements does not include only those elements but may include other elements not expressly listed or inherent to such process, method, article, or apparatus. Without further limitation, an element defined by the phrase "comprising an … …" does not exclude the presence of other like elements in a process, method, article, or apparatus that comprises the element.
While the present invention has been described with reference to the embodiments shown in the drawings, the present invention is not limited to the embodiments, which are illustrative and not restrictive, and it will be apparent to those skilled in the art that various changes and modifications can be made therein without departing from the spirit and scope of the invention as defined in the appended claims.
Claims (10)
1. A positive electrode sheet, comprising: a current collector, a first coating, a second coating, and a protective layer, wherein,
the first coating is coated on a first area of the surface of the current collector, the second coating is coated on a second area of the surface of the current collector, the first area is adjacent to the second area, and a hollow foil area is arranged between the first coating and the second coating;
the protective layer covers a surface of the second coating and the empty foil region.
2. The positive electrode sheet according to claim 1, wherein the protective layer further covers the edge of the first coating layer adjacent to the second coating layer, the first edge of the protective layer is located on the surface of the first coating layer, and the first edge of the protective layer is spaced from the edge of the first coating layer adjacent to the second coating layer by a distance of 0 to 3 mm.
3. The positive electrode sheet according to claim 1, wherein the empty foil region includes at least one sub empty foil region, and the sub empty foil regions communicate with opposite ends of the current collector in a width direction of the current collector.
4. The positive electrode sheet according to claim 3, wherein the width of the sub-empty foil region is 0.1 to 3 mm.
5. The positive electrode sheet according to claim 3, wherein the shape of the sub-empty foil region is a wavy line, a zigzag line or a straight line.
6. The positive electrode sheet according to claim 1, wherein the first coating layer includes a notch formed by recessing inward from the first side thereof, the notch being the empty foil region;
the notch is disposed around the second coating.
7. The positive electrode sheet according to claim 6, wherein the width of the notch is 0.1 to 3 mm.
8. The positive electrode sheet according to claim 7, wherein the shape of the notch is a U-shape, a mouth-shape, an X-shape, a Z-shape or a field-shape.
9. A battery comprising a positive electrode sheet according to any one of claims 1 to 8, wherein the protective layer is located at the end of the positive electrode sheet.
10. A battery comprising the positive electrode sheet according to any one of claims 1 to 8, and further comprising a negative electrode sheet and a negative electrode tab fixed to a surface of the negative electrode sheet, wherein the protective layer is provided on the positive electrode sheet at a position corresponding to the negative electrode tab.
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Citations (6)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
JP2007165224A (en) * | 2005-12-16 | 2007-06-28 | Matsushita Electric Ind Co Ltd | Nonaqueous electrolytic secondary battery |
CN105449160A (en) * | 2016-01-07 | 2016-03-30 | 广东凯德能源科技有限公司 | Break-resistant high-energy-density lithium ion battery positive plate and preparation method |
CN107834014A (en) * | 2017-09-18 | 2018-03-23 | 东莞市迈科新能源有限公司 | A kind of high power cylindrical lithium ion cell core |
CN207947341U (en) * | 2018-03-27 | 2018-10-09 | 横店集团东磁股份有限公司 | A kind of anode pole piece with lug and the lithium ion battery comprising the anode pole piece |
CN112103474A (en) * | 2020-09-15 | 2020-12-18 | 横店集团东磁股份有限公司 | Processing method of winding type lithium battery positive plate and winding type lithium battery positive plate |
CN113036075A (en) * | 2021-02-26 | 2021-06-25 | 珠海冠宇电池股份有限公司 | Pole piece and battery cell |
-
2021
- 2021-11-18 CN CN202111367463.8A patent/CN113903921B/en active Active
Patent Citations (6)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
JP2007165224A (en) * | 2005-12-16 | 2007-06-28 | Matsushita Electric Ind Co Ltd | Nonaqueous electrolytic secondary battery |
CN105449160A (en) * | 2016-01-07 | 2016-03-30 | 广东凯德能源科技有限公司 | Break-resistant high-energy-density lithium ion battery positive plate and preparation method |
CN107834014A (en) * | 2017-09-18 | 2018-03-23 | 东莞市迈科新能源有限公司 | A kind of high power cylindrical lithium ion cell core |
CN207947341U (en) * | 2018-03-27 | 2018-10-09 | 横店集团东磁股份有限公司 | A kind of anode pole piece with lug and the lithium ion battery comprising the anode pole piece |
CN112103474A (en) * | 2020-09-15 | 2020-12-18 | 横店集团东磁股份有限公司 | Processing method of winding type lithium battery positive plate and winding type lithium battery positive plate |
CN113036075A (en) * | 2021-02-26 | 2021-06-25 | 珠海冠宇电池股份有限公司 | Pole piece and battery cell |
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