CN112750976A - Lithium battery core and lithium ion battery - Google Patents
Lithium battery core and lithium ion battery Download PDFInfo
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- CN112750976A CN112750976A CN202011597847.4A CN202011597847A CN112750976A CN 112750976 A CN112750976 A CN 112750976A CN 202011597847 A CN202011597847 A CN 202011597847A CN 112750976 A CN112750976 A CN 112750976A
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- WHXSMMKQMYFTQS-UHFFFAOYSA-N Lithium Chemical compound [Li] WHXSMMKQMYFTQS-UHFFFAOYSA-N 0.000 title claims abstract description 158
- 229910052744 lithium Inorganic materials 0.000 title claims abstract description 158
- HBBGRARXTFLTSG-UHFFFAOYSA-N Lithium ion Chemical compound [Li+] HBBGRARXTFLTSG-UHFFFAOYSA-N 0.000 title claims description 17
- 229910001416 lithium ion Inorganic materials 0.000 title claims description 17
- 239000010410 layer Substances 0.000 claims abstract description 226
- 239000007773 negative electrode material Substances 0.000 claims abstract description 116
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- 238000000576 coating method Methods 0.000 claims abstract description 75
- 239000002245 particle Substances 0.000 claims abstract description 36
- 239000002346 layers by function Substances 0.000 claims abstract description 35
- 239000011149 active material Substances 0.000 claims abstract description 30
- 239000007774 positive electrode material Substances 0.000 claims description 122
- 238000009792 diffusion process Methods 0.000 claims description 37
- 239000007790 solid phase Substances 0.000 claims description 37
- 238000004804 winding Methods 0.000 claims description 18
- 239000002356 single layer Substances 0.000 claims description 13
- 238000001556 precipitation Methods 0.000 abstract description 21
- 239000002002 slurry Substances 0.000 description 39
- 210000004027 cell Anatomy 0.000 description 26
- 239000006183 anode active material Substances 0.000 description 19
- 239000011230 binding agent Substances 0.000 description 14
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- 230000000052 comparative effect Effects 0.000 description 11
- VNWKTOKETHGBQD-UHFFFAOYSA-N methane Chemical compound C VNWKTOKETHGBQD-UHFFFAOYSA-N 0.000 description 11
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- -1 nickel-cobalt-aluminum Chemical compound 0.000 description 3
- 238000005096 rolling process Methods 0.000 description 3
- 229920000049 Carbon (fiber) Polymers 0.000 description 2
- RTAQQCXQSZGOHL-UHFFFAOYSA-N Titanium Chemical compound [Ti] RTAQQCXQSZGOHL-UHFFFAOYSA-N 0.000 description 2
- KFDQGLPGKXUTMZ-UHFFFAOYSA-N [Mn].[Co].[Ni] Chemical compound [Mn].[Co].[Ni] KFDQGLPGKXUTMZ-UHFFFAOYSA-N 0.000 description 2
- 239000013543 active substance Substances 0.000 description 2
- 229910021383 artificial graphite Inorganic materials 0.000 description 2
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- 239000006182 cathode active material Substances 0.000 description 2
- 239000003153 chemical reaction reagent Substances 0.000 description 2
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- XAGFODPZIPBFFR-UHFFFAOYSA-N aluminium Chemical compound [Al] XAGFODPZIPBFFR-UHFFFAOYSA-N 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
- H01M10/00—Secondary cells; Manufacture thereof
- H01M10/05—Accumulators with non-aqueous electrolyte
- H01M10/052—Li-accumulators
- H01M10/0525—Rocking-chair batteries, i.e. batteries with lithium insertion or intercalation in both electrodes; Lithium-ion batteries
-
- H—ELECTRICITY
- H01—ELECTRIC ELEMENTS
- H01M—PROCESSES OR MEANS, e.g. BATTERIES, FOR THE DIRECT CONVERSION OF CHEMICAL ENERGY INTO ELECTRICAL ENERGY
- H01M10/00—Secondary cells; Manufacture thereof
- H01M10/05—Accumulators with non-aqueous electrolyte
- H01M10/058—Construction or manufacture
- H01M10/0587—Construction or manufacture of accumulators having only wound construction elements, i.e. wound positive electrodes, wound negative electrodes and wound separators
-
- H—ELECTRICITY
- H01—ELECTRIC ELEMENTS
- H01M—PROCESSES OR MEANS, e.g. BATTERIES, FOR THE DIRECT CONVERSION OF CHEMICAL ENERGY INTO ELECTRICAL ENERGY
- H01M10/00—Secondary cells; Manufacture thereof
- H01M10/42—Methods or arrangements for servicing or maintenance of secondary cells or secondary half-cells
- H01M10/4235—Safety or regulating additives or arrangements in electrodes, separators or electrolyte
-
- H—ELECTRICITY
- H01—ELECTRIC ELEMENTS
- H01M—PROCESSES OR MEANS, e.g. BATTERIES, FOR THE DIRECT CONVERSION OF CHEMICAL ENERGY INTO ELECTRICAL ENERGY
- H01M4/00—Electrodes
- H01M4/02—Electrodes composed of, or comprising, active material
- H01M4/13—Electrodes for accumulators with non-aqueous electrolyte, e.g. for lithium-accumulators; Processes of manufacture thereof
-
- H—ELECTRICITY
- H01—ELECTRIC ELEMENTS
- H01M—PROCESSES OR MEANS, e.g. BATTERIES, FOR THE DIRECT CONVERSION OF CHEMICAL ENERGY INTO ELECTRICAL ENERGY
- H01M4/00—Electrodes
- H01M4/02—Electrodes composed of, or comprising, active material
- H01M4/62—Selection of inactive substances as ingredients for active masses, e.g. binders, fillers
- H01M4/628—Inhibitors, e.g. gassing inhibitors, corrosion inhibitors
-
- 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
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- Chemical Kinetics & Catalysis (AREA)
- Electrochemistry (AREA)
- General Chemical & Material Sciences (AREA)
- Manufacturing & Machinery (AREA)
- Materials Engineering (AREA)
- Battery Electrode And Active Subsutance (AREA)
- Secondary Cells (AREA)
Abstract
The invention relates to a lithium battery core, which comprises a positive plate and a negative plate, wherein the negative (positive) plate comprises a current collector and a negative (positive) functional layer coated on at least one surface of the current collector, a negative (positive) tab is arranged on a first (third) surface of the negative (positive) current collector, a first (fourth) surface functional layer opposite to the third surface comprises a double-layer coating area close to the negative (positive) tab, the double-layer coating area comprises a first negative (positive) active material layer and a second negative (positive) active material layer, the first negative (positive) active material layer is positioned between the surface of the negative (positive) current collector and the second negative (positive) active material layer, the particle size of a first negative (positive) active material in the first negative (positive) active material layer is larger than (smaller than) that of a second negative active material in the second negative (positive) active material layer, the battery core is applied to the lithium battery, so that the lithium precipitation phenomenon of the negative electrode of the lithium battery can be well inhibited.
Description
Technical Field
The invention relates to the field of lithium batteries, in particular to a lithium battery cell and a lithium ion battery.
Background
The lithium ion battery has the advantages of high working voltage, high energy density, long cycle life, environmental friendliness and the like, and is widely applied to the fields of 3C digital products, electric automobiles, military aerospace and the like. With the popularization and application of intelligent digital products and the wide application of new energy automobiles, the requirements for shortening the charging time of the lithium ion battery and improving the energy density of the lithium ion battery become more urgent, and correspondingly higher requirements for the charging speed and the charging voltage of the lithium ion battery are provided.
At present, most batteries used for digital products adopt a winding structure, and the requirements of high energy density and high charging speed are often required to be met simultaneously. However, after the battery is charged and discharged for a certain number of times, the lithium separation phenomenon is easy to occur in the region of the negative plate adjacent to the tab, and the lithium separation is more serious when the charging current is larger. Lithium precipitated from the negative electrode forms dendrite, the dendrite is easy to pierce through a diaphragm to cause short circuit of the battery, the battery is caused to smoke, fire and even explode, and the potential safety hazard is serious, so that the lithium precipitation from the negative electrode is required to be inhibited, and the safety of the battery is ensured.
In the existing lithium ion battery manufacturing technology, slurry with the same formula is adopted for the whole coating of the pole piece, the types, the contents and the coating thicknesses of active substances in all regions in the length direction of the pole piece are kept consistent, and the lithium precipitation phenomenon is easily caused in the region of the cathode piece adjacent to the pole lug.
Therefore, optimizing the composition structure of the pole piece in the lithium battery cell can better inhibit the negative pole from separating lithium, thereby being capable of adapting to larger charging current, having faster charging speed and longer service life, and being an important problem to be solved urgently by technical personnel in the field.
Disclosure of Invention
The invention aims to provide a lithium battery cell which can better inhibit the lithium precipitation phenomenon of a lithium battery cathode when being applied to a lithium battery.
The invention also provides a lithium ion battery comprising the lithium battery cell, and the lithium ion battery assembled by the cell can better inhibit the lithium precipitation phenomenon of the negative electrode of the lithium battery and has better cycle performance.
In one aspect of the invention, a lithium battery core is provided, which includes a positive plate and a negative plate, the negative plate includes a negative current collector and a negative functional layer coated on at least one surface of the negative current collector, a negative tab is disposed on a first surface of the negative current collector, the functional layer on the first surface includes a double-layer coating region near the negative tab, the double-layer coating region includes a first negative active material layer and a second negative active material layer, the first negative active material layer is disposed between the surface of the negative current collector and the second negative active material layer, and a particle size of a first negative active material in the first negative active material layer is larger than a particle size of a second negative active material in the second negative active material layer.
The positive plate comprises a positive current collector and a positive functional layer coated on at least one surface of the positive current collector, a positive pole lug is arranged on a third surface of the positive current collector, the functional layer on a fourth surface opposite to the third surface comprises a double-layer coating area close to the positive pole lug, the double-layer coating area comprises a first positive active material layer and a second positive active material layer, the first positive active material layer is located between the surface of the positive current collector and the second positive active material layer, and the particle size of a first positive active material in the first positive active material layer is smaller than that of a second positive active material in the second positive active material layer.
The invention provides the battery cell formed by the positive plate and the negative plate with continuous active material coating and segmented dynamic performance by controlling the particle size of active substances in the positive plate and the negative plate and changing the structure of the positive plate and the negative plate in the battery cell, so that lithium separation is more difficult to occur from the two aspects of improving the lithium intercalation performance of the negative plate and inhibiting the lithium removal performance of the positive plate, and the problem of lithium separation of the negative plate in the rapid charge-discharge cycle process of the conventional lithium ion battery is solved.
In one embodiment of the present invention, the exchange current density of lithium and the solid-phase diffusion coefficient of lithium in the second negative electrode active material may be larger than the exchange current density of lithium and the solid-phase diffusion coefficient of lithium in the first negative electrode active material; the exchange current density of lithium and the solid-phase diffusion coefficient of lithium in the first positive electrode active material may also be greater than the exchange current density of lithium and the solid-phase diffusion coefficient of lithium in the second positive electrode active material. By further controlling the solid-phase diffusion coefficient and the lithium exchange current density of lithium in the negative electrode active materials in the first negative electrode active material layer and the second negative electrode active material layer, and the solid-phase diffusion coefficient and the lithium exchange current density of lithium in the positive electrode active materials in the first positive electrode active material layer and the second positive electrode active material layer, the lithium intercalation performance of the negative electrode plate is further improved, and the separation performance of the positive electrode plate is inhibited.
According to the research of the invention, the D50 particle size of the first negative electrode active material in the negative electrode sheet is R103, the D50 particle size of the second negative electrode active material is R104, R103 is more than or equal to 5 microns and less than or equal to 30 microns, R104 is more than or equal to 1 micron and less than or equal to 20 microns, and R103-R104 are more than or equal to 2 microns.
Furthermore, the particle size of D50 of the first positive electrode active material in the positive electrode sheet is R203, the particle size of D50 of the second positive electrode active material is R204, R203 is more than or equal to 1 mu m and less than or equal to 28 mu m, R204 is more than or equal to 3 mu m and less than or equal to 30 mu m, and R204-R203 are more than or equal to 2 mu m.
According to a further study of the present invention, the exchange current density of lithium (noted as i) in the second negative electrode active material0104) Exchange current density (denoted as i) with lithium in the first negative electrode active material0103) The ratio of (a) to (b) is not less than 1.1, and may be further 1.1 to 100, and the ratio of the solid phase diffusion coefficient of lithium (described as D104) in the second anode active material to the solid phase diffusion coefficient of lithium (described as D103) in the first anode active material is not less than 1.2, and may be further 1.2 to 1000. Wherein, 0.05A/m2≤i 0103≤1A/m2,0.05A/m2≤i 0104≤1A/m2,10-16≤D103≤10-9,10-16≤D104≤10-9。
Further, the exchange current density (denoted as i) of lithium in the first positive electrode active material0203) Exchange current density (denoted as i) with lithium in the second positive electrode active material0204) The ratio of (a) to (b) is not less than 1.1, and may be 1.1 to 100, and the ratio of the solid phase diffusion coefficient of lithium (denoted as D203) in the first positive electrode active material to the solid phase diffusion coefficient of lithium (denoted as D204) in the second positive electrode active material is not less than 1.2, and may be 1.2 to 1000. Wherein, 0.1A/m2≤i 0203≤2A/m2,0.1A/m2≤i 0204≤2A/m2,10-16≤D203≤10-9,10-16≤D204≤10-9。
According to the research of the invention, the first negative active material and the second negative active material can be at least one of artificial graphite, natural graphite, mesocarbon microbeads, soft carbon, hard carbon, a silicon-based material, a graphite-silicon composite material and lithium titanate; the first positive electrode active material and the second positive electrode active material may each be at least one of lithium cobaltate, a nickel-cobalt-manganese ternary material, a nickel-cobalt-aluminum ternary material, and lithium iron phosphate.
In specific implementation, on the basis that each layer of active material meets the requirement of the particle size, the active material with the target particle size, lithium exchange current density and lithium solid-phase diffusion coefficient can be selected by further screening the active material by testing the exchange current density of lithium and the solid-phase diffusion coefficient of lithium. For example, each of the first and second negative electrode active materials may be graphite but it is graphite having different particle diameters, lithium exchange current densities, and lithium solid-phase diffusion coefficients, and each of the first and second positive electrode active materials may be lithium cobaltate but it is lithium cobaltate having different particle diameters, lithium exchange current densities, and lithium solid-phase diffusion coefficients.
It should be further noted that the positive electrode active material/negative electrode active material with different particle diameters does not necessarily have different lithium exchange current densities and lithium solid-phase diffusion coefficients, and the particle diameters, the lithium exchange current densities and the lithium solid-phase diffusion coefficients are three independent influencing factors influencing the lithium intercalation and lithium deintercalation performance of the active material in the active material layer in the electrode sheet.
In an embodiment of the present invention, in the above-mentioned battery cell, the lengths of the first negative electrode active material layer and the second negative electrode active material layer in the negative electrode sheet and the lengths of the first positive electrode active material layer and the second positive electrode active material layer in the positive electrode sheet may be generally set according to the length of the region adjacent to the negative electrode tab where lithium is easily separated, for example, when the battery cell is a winding type battery cell, the lengths of the first negative electrode active material layer in the negative electrode sheet are L103, the length of the second negative electrode active material layer is L104, the winding core width is W, and the lengths of the first negative electrode active material layer and the second negative electrode active material layer and the winding core width satisfy the following conditions: l103 is more than or equal to 0.5W and less than or equal to 3W, and L104 is more than or equal to 0.5W and less than or equal to 3W. The length of the first positive active material layer in the positive plate is L203, the length of the second positive active material layer is L204, the winding core width is W, and the lengths of the first positive active material layer and the second positive active material layer and the winding core width satisfy the following conditions: l203 is more than or equal to 0.5W and less than or equal to 3W, and L204 is more than or equal to 0.5W and less than or equal to 3W. According to the research of the invention, in the winding type battery cell, the lithium is easily separated from the 0.5W-3W area of the negative plate adjacent to the negative pole tab, the lithium embedding performance of the area can be better improved by the design of the double-layer coating area of the negative plate, and the lithium removing performance of the area can be better inhibited by the design of the double-layer coating area of the positive plate, so that the lithium separation phenomenon of the area adjacent to the tab of the negative pole of the lithium battery in the rapid charging and discharging process can be better inhibited by the battery cell formed by the positive plate and the negative plate which meets the condition. The core width W is the length in the horizontal direction of the innermost circle formed by winding the cell.
It can be understood that, in the battery cell of the present invention, the double-layer coating region in the positive plate and the double-layer coating region in the negative plate are located on two opposite surfaces of the diaphragm in the formed battery cell, and the positions of the double-layer coating regions are mirror symmetry with respect to the diaphragm, which is beneficial for simultaneously playing the role of improving lithium intercalation of the negative electrode and inhibiting lithium deintercalation of the positive electrode at the position of the battery cell adjacent to the negative electrode tab.
In a preferred embodiment of the present invention, the length of the first anode active material layer and the length of the second anode active material layer may be equal. The length of the first positive electrode active material layer and the length of the second positive electrode active material layer may be equal.
In a preferred embodiment of the present invention, the distance between the first negative electrode active material layer and the current collector end point on the side close to the negative electrode tab is equal to the distance between the second negative electrode active material layer and the current collector end point on the side close to the negative electrode tab, that is, when the slurry forming the first negative electrode active material layer and the slurry forming the second negative electrode active material layer are both coated from the side close to the negative electrode tab at the time of preparing the negative electrode sheet, the coating starting points of the two layers are the same; when the slurry forming the first negative electrode active material layer and the slurry forming the second negative electrode active material layer are both coated from the side away from the negative electrode tab, the coating end points of the two layers are the same. The distance between the first positive electrode active material layer and the current collector end point close to the positive electrode lug is equal to the distance between the second positive electrode active material layer and the current collector end point close to the positive electrode lug, namely, when the positive plate is prepared, when the slurry forming the first positive electrode active material layer and the slurry forming the second positive electrode active material layer are coated from the side close to the positive electrode lug, the coating starting points of the two layers are the same; when the slurry forming the first positive electrode active material layer and the slurry forming the second positive electrode active material layer are both coated from the side away from the positive electrode tab, the coating end points of the two layers are the same.
In one embodiment of the present invention, the raw material of the first anode active material layer may include: 70-99 wt% of a first negative active material, 0.5-15 wt% of a conductive agent, and 0.5-15 wt% of a binder, and the second negative active material layer may include: 70-99 wt% of second negative electrode active material, 0.5-15 wt% of conductive agent and 0.5-15 wt% of binder. Further, the raw materials of the first anode active material layer may generally include: 80-98 wt% of a first negative active material, 1-10 wt% of a conductive agent, and 1-10 wt% of a binder, and the raw material of the second negative active material layer may generally include: 80-98 wt% of second negative electrode active material, 1-10 wt% of conductive agent and 1-10 wt% of binder.
In one embodiment of the present invention, the raw material of the first cathode active material layer may include: 70-99 wt% of first positive electrode active material, 0.5-15 wt% of conductive agent and 0.5-15 wt% of binder, and the raw material of the second positive electrode active material layer may include: 70-99 wt% of second positive electrode active material, 0.5-15 wt% of conductive agent and 0.5-15 wt% of binder.
In a preferred embodiment of the present invention, the raw materials of the first positive electrode active material layer may generally include: 80-98 wt% of a first positive electrode active material, 1-10 wt% of a conductive agent and 1-10 wt% of a binder, and the raw material of the second negative electrode active material layer may generally include: 80-98 wt% of second positive electrode active material, 1-10 wt% of conductive agent and 1-10 wt% of binder.
The positive plate and the negative plate in the battery cell can be prepared by the following steps: and sequentially coating first negative electrode (positive electrode) active material layer slurry and second negative electrode (positive electrode) active material layer slurry in the area of a negative electrode (positive electrode) current collector close to a negative electrode (positive electrode) lug to form a first negative electrode (positive electrode) active material layer and a second negative electrode (positive electrode) active material layer, wherein the first negative electrode (positive electrode) active material layer and the second negative electrode (positive electrode) active material layer form a functional layer of a negative electrode (positive electrode) piece of a lithium battery. Wherein the solid contents of the slurry forming the first negative electrode (positive electrode) active material layer and the slurry forming the second negative electrode (positive electrode) active material layer may be 40 wt% to 45 wt%.
In an embodiment of the present invention, the functional layer of the negative electrode sheet for a lithium battery further includes a first normal coating region that is far away from the negative electrode tab and is connected to the double-layer coating region, the first normal coating region is formed by a single-layer third negative electrode active material layer, and a sum of a capacity per unit area of the first negative electrode active material layer and a capacity per unit area of the second negative electrode active material layer is not less than a capacity per unit area of the third negative electrode active material layer; the functional layer of the lithium battery positive plate further comprises a second normal coating area which is far away from the positive pole lug and is connected with the double-layer coating area, the second normal coating area is formed by a single-layer third positive active material layer, and the sum of the unit area capacity of the first positive active material layer and the unit area capacity of the second positive active material layer is not less than the unit area capacity of the third positive active material layer, so that the positive plate is favorable for having higher consistency, and the lithium precipitation phenomenon of the negative plate is better inhibited.
It can be understood that after the above-mentioned double-layer coating region is coated according to the research of the present invention, the first (second) normal coating region connected to the double-layer coating region is coated with a single layer, which is beneficial to reduce the processing procedures of the positive electrode sheet (negative electrode sheet) and save the processing time.
In one embodiment of the present invention, the raw material of the third anode active material layer may include: 80-98 wt% of a third negative active material, 1-10 wt% of a conductive agent, and 1-10 wt% of a binder, preferably, comprising: 70-99 wt% of negative electrode active material, 0.5-15 wt% of conductive agent and 0.5-15 wt% of binder.
In one embodiment of the present invention, the raw material of the third cathode active material layer may include: 70-99 wt% of third positive electrode active material, 0.5-15 wt% of conductive agent and 0.5-15 wt% of binder, preferably, 80-98 wt% of third positive electrode active material, 1-10 wt% of conductive agent and 1-10 wt% of binder.
The particle size, the lithium exchange current density, and the solid phase diffusion coefficient of lithium of the third negative electrode active material may be the same as or different from those of the first negative electrode active material and the second negative electrode active material, and the particle size, the lithium exchange current density, and the solid phase diffusion coefficient of lithium of the third positive electrode active material may be the same as or different from those of the first positive electrode active material and the second positive electrode active material, and the present invention is not particularly limited thereto.
The third negative active material may include at least one of artificial graphite, natural graphite, mesocarbon microbeads, soft carbon, hard carbon, a silicon-based material, a graphite-silicon composite material, and lithium titanate, and the third positive active material may include at least one of lithium cobaltate, a nickel-cobalt-manganese ternary material, a nickel-cobalt-aluminum ternary material, and lithium iron phosphate.
The conductive agent and the binder in the raw materials of each active material layer can be the same or different, and the conductive agent can comprise at least one of conductive carbon black, acetylene black, ketjen black, conductive graphite, conductive carbon fiber, carbon nano tube, metal powder and carbon fiber; the binder may include at least one of sodium carboxymethylcellulose, styrene-butadiene latex, polytetrafluoroethylene, and polyethylene oxide.
According to the research of the invention, the thickness of the first negative electrode active material layer in the negative plate is T103, the thickness of the second negative electrode active material layer is T104, the thickness of the third negative electrode active material layer is T105, T103 is more than or equal to 10 microns and less than or equal to 60 microns, T104 is more than or equal to 10 microns and less than or equal to 60 microns, T103 is more than or equal to 50 microns, T103 is more than or equal to 10 microns and less than or equal to 50 microns, and T103+ T104-T105 is more than or equal to 6 microns; the thickness of the first positive active material layer in the positive plate is T203, the thickness of the second positive active material layer is T204, the thickness of the third positive active material layer is T205, T203 is more than or equal to 10 microns and less than or equal to 60 microns, T204 is more than or equal to 10 microns and less than or equal to 60 microns, T103 is more than or equal to 50 microns and less than or equal to 50 microns, T203+ T204-T205 is more than or equal to 3 microns and less than or equal to 50 microns, the negative plate with more uniform thickness is obtained, and the negative plate is prevented from being broken in the rolling process.
Generally, there is also a non-functional layer coated area on the positive current collector (denoted as positive current collector empty area).
In one embodiment of the present invention, both surfaces of the negative electrode current collector and the positive electrode current collector are coated with a functional layer, and the functional layer on the second surface opposite to the first surface includes a third normal coating region in mirror symmetry with the first normal coating region, and the third normal coating region is formed by a single layer of a third negative electrode active material layer, which is beneficial to improving the energy density of the negative electrode sheet; the two surfaces of the positive current collector are coated with positive functional layers, the functional layer on the third surface opposite to the fourth surface comprises a fourth normal coating area which is in mirror symmetry with the double-layer coating area and the second normal coating area, and the fourth normal coating area is formed by a single-layer third positive active material layer.
In the invention, the functional layer (marked as a single-surface area) is not coated in the area of the second surface of the negative plate which is mirror-symmetrical to the double-layer coating area, so that the lithium precipitation phenomenon of the negative plate can be further inhibited, and the single-surface area is not arranged in the positive plate.
In an embodiment of the invention, the battery cell may be a winding battery cell, in the winding battery cell, the length of the first negative electrode active material layer in the negative electrode sheet is L103, the length of the second negative electrode active material layer is L104, the width of the winding core is W, L103 is greater than or equal to 0.5W and less than or equal to 3W, and L104 is greater than or equal to 0.5W and less than or equal to 3W; the length of the first positive active material layer in the positive plate is L203, the length of the second positive active material layer is L204, the width of the winding core is W, L203 is more than or equal to 0.5W and less than or equal to 3W, and L204 is more than or equal to 0.5W and less than or equal to 3W.
In another aspect of the present invention, a lithium ion battery is provided, which includes the above-mentioned winding type battery cell.
The embodiment of the invention has at least the following beneficial effects:
the battery core provided by the invention is applied to the lithium battery, can better inhibit the lithium precipitation phenomenon of the lithium battery, and improves the comprehensive performances of the battery, such as cycling stability, safety and the like; the capacity retention rate of the lithium battery obtained by assembling the lithium battery after 500 times of circulation can reach 88 percent, and even is higher than 94 percent.
The lithium ion battery comprising the battery cell provided by the invention has the advantages of better capability of inhibiting lithium precipitation of the lithium battery, safety and cycling stability.
Drawings
Fig. 1 is a schematic structural diagram of a negative electrode sheet according to an embodiment of the invention;
FIG. 2 is a schematic structural diagram of a positive plate according to an embodiment of the present invention;
fig. 3 is a schematic structural diagram of a wound battery cell according to an embodiment of the invention.
Description of reference numerals:
101. a negative electrode tab; 102. a negative current collector; 103. a first negative electrode active material layer; 104. a second anode active material layer; 105. a third negative electrode active material layer; 201. a positive electrode tab; 202. a positive current collector; 203. a first positive electrode active material layer; 204. a second positive electrode active material layer; 205. and a third positive electrode active material layer.
Detailed Description
In order that those skilled in the art will better understand the concept of the present invention, the following detailed description is given with reference to the accompanying drawings.
As shown in fig. 3, the present invention provides a winding type battery cell, including a negative electrode sheet and a positive electrode sheet, where the negative electrode sheet includes a negative electrode current collector 102 and a functional layer coated on one surface of the negative electrode current collector 102 as shown in fig. 1, the functional layer on the first surface includes a double-layer coating region near a negative electrode tab 101, the double-layer coating region includes a first negative electrode active material layer 103 and a second negative electrode active material layer 104, and the first negative electrode active material layer is located between the surface of the negative electrode current collector 102 and the second negative electrode active material layer 104. The functional layer further includes a first normal coating region remote from the anode tab 101 and connected to the double-layer coating region, the first normal coating region being formed of a single layer of the third anode active material layer 105. Both surfaces of the negative electrode current collector are coated with a functional layer, and the functional layer of the second surface opposite to the first surface includes a third normal coating region in mirror symmetry with the first normal coating region, the third normal coating region being formed of a single layer of the third negative electrode active material layer 105.
As shown in fig. 2, the positive electrode sheet includes a positive electrode current collector 202 and a functional layer coated on at least one surface of the positive electrode current collector 202, a positive electrode tab 201 is disposed on a third surface of the positive electrode current collector, the functional layer on a fourth surface opposite to the third surface includes a double-layer coating region near the positive electrode tab 201, the double-layer coating region includes a first positive electrode active material layer 203 and a second positive electrode active material layer 204, the first positive electrode active material layer 203 is located between the surface of the positive electrode current collector 202 and the second positive electrode active material layer 204, the functional layer further includes a second normal coating region far from the positive electrode tab 201 and connected to the double-layer coating region, and the second normal coating region is formed by a single-layer third positive electrode active material layer 205; both surfaces of the positive current collector are coated with functional layers, and the functional layer of the third surface opposite to the fourth surface includes a fourth normal coating region in mirror symmetry with the double-layer coating region and the second normal coating region, which is formed of a single-layer third positive active material layer 205.
In order to make the objects, technical solutions and advantages of the present invention clearer, the technical solutions in the implementation of the present invention will be clearly and completely described below with reference to the examples and comparative examples of the present invention, and it is obvious that the described examples are a part of the examples of the present invention, but not all of the examples. 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 invention.
Unless otherwise specified, the experimental methods used in the following examples are all conventional methods; the reagents, materials, instruments and the like used in the following examples and comparative examples are all conventional reagents, conventional materials and conventional instruments.
Example 1
Preparing a negative plate: respectively preparing slurry for forming a first negative electrode active material layer, slurry for forming a second negative electrode active material layer and slurry for forming a third negative electrode active material layer; wherein the slurry composition of the first anode active material layer is: 97 wt% of graphite, 1 wt% of conductive carbon black and 2 wt% of styrene-butadiene latex, wherein the solid content is 40-45 wt%; the slurry composition of the second anode active material layer was: 97 wt% of graphite, 1 wt% of conductive carbon black and 2 wt% of styrene-butadiene latex, wherein the solid content is 40-45 wt%; the slurry composition of the third anode active material layer was: 97 wt% of graphite, 1 wt% of conductive carbon black and 2 wt% of styrene-butadiene latex, wherein the solid content is 40-45 wt%. The particle diameter of D50 (R103) of the first negative electrode active material in the slurry for forming the first negative electrode active material layer, and the exchange current density (i) of lithium in the first negative electrode active material0103) A solid-phase diffusion coefficient (D103) of lithium, a D50 particle diameter (R104) of the second negative electrode active material in the slurry forming the second negative electrode active material layer, and an exchange current density (i) of lithium in the second negative electrode active material0104) A solid-phase diffusion coefficient (D104) of lithium, a D50 particle diameter (R105) of the third negative electrode active material in the slurry forming the third negative electrode active material layer, and an exchange current density (i) of lithium in the third negative electrode active material0105) The solid phase diffusion coefficient (D105) of lithium is shown in table 1.
And sequentially coating the slurry on a negative current collector to form a first negative active material layer, a second negative active material layer and a third negative active material layer, and drying and rolling to obtain a negative plate, wherein the structure of the negative plate is shown in fig. 1, the length (L103) of the first negative active material layer is equal to the length (L104) of the second negative active material layer, and the length of a negative double-layer coating area formed by the first negative active material layer and the second negative active material layer is recorded as L1034. The negative electrode double-layer coating region length (L1034), the third negative electrode active material layer length (L105), the first negative electrode active material layer thickness (T103), the second negative electrode active material layer thickness (T104), and the third negative electrode active material layer thickness (T105) are shown in table 1.
Preparing a positive plate: respectively preparing slurry for forming a first positive electrode active material layer, slurry for forming a second positive electrode active material layer and slurry for forming a third positive electrode active material layer; wherein the slurry composition of the first positive electrode active material layer is: 96 wt% of lithium cobaltate, 2 wt% of conductive carbon black and 2 wt% of polyvinylidene fluoride, wherein the solid content of the lithium cobaltate, the conductive carbon black and the polyvinylidene fluoride is 40-45 wt%; the slurry composition of the second positive electrode active material layer was: 96 wt% of lithium cobaltate, 2 wt% of conductive carbon black and 2 wt% of polyvinylidene fluoride, wherein the solid content of the lithium cobaltate, the conductive carbon black and the polyvinylidene fluoride is 40-45 wt%; the slurry composition of the third positive electrode active material layer was: 96 wt% of lithium cobaltate, 2 wt% of conductive carbon black and 2 wt% of polyvinylidene fluoride, and the solid content is 40-45 wt%. D50 particle diameter (R203) of the first positive electrode active material in the slurry for forming the first positive electrode active material layer, and exchange current density (i) of lithium in the first positive electrode active material0203) The solid-phase diffusion coefficient of lithium (D203), the D50 particle diameter of the second positive electrode active material in the slurry for forming the second positive electrode active material layer (R204), and the exchange current density of lithium in the second positive electrode active material (i)0204) A solid-phase diffusion coefficient (D204) of lithium, a D50 particle diameter (R205) of the third positive electrode active material in the slurry forming the third positive electrode active material layer, and an exchange current density (i) of lithium in the third positive electrode active material0205) The solid phase diffusion coefficient (D205) of lithium is shown in table 2.
The slurry prepared in the above manner is sequentially coated on a positive electrode current collector to form a first positive electrode active material layer, a second positive electrode active material layer and a third positive electrode active material layer, and the positive electrode sheet is obtained by drying and rolling, and the structure of the positive electrode sheet is shown in fig. 2, wherein the length of the positive electrode current collector is 1018mm, the length of the vacant region of the positive electrode current collector along the length direction of the negative electrode current collector is 50mm, the length of the first positive electrode active material layer (L203) is equal to the length of the second positive electrode active material layer (L204), and the length of the positive electrode double-layer coating region formed by the first positive electrode active material layer and the second positive electrode active material layer is denoted as L2034. The positive electrode double coating region length (L2034), the length of the third positive electrode active material layer (L205), the first positive electrode active material layer thickness (T203), the second positive electrode active material layer thickness (T204), and the third positive electrode active material layer thickness (T205) are shown in table 2.
Assembling the battery cell: and (3) winding the prepared negative plate, the positive plate and the diaphragm together to form a winding core (the width is 62mm), packaging by using an aluminum plastic film, baking to remove moisture, injecting electrolyte, and performing hot pressing to obtain the battery core.
Examples 2 to 6 and comparative examples 1 to 5
Examples 2 to 6 and comparative examples 1 to 5 were the same as in the preparation procedure of example 1, except that the particle diameter of D50 (R103) of the first anode active material in the slurry forming the first anode active material layer, and the exchange current density (i) of lithium in the first anode active material were different0103) A solid-phase diffusion coefficient (D103) of lithium, a D50 particle diameter (R104) of the second negative electrode active material in the slurry forming the second negative electrode active material layer, and an exchange current density (i) of lithium in the second negative electrode active material0104) A solid-phase diffusion coefficient (D104) of lithium, a D50 particle diameter (R105) of the third negative electrode active material in the slurry forming the third negative electrode active material layer, and an exchange current density (i) of lithium in the third negative electrode active material0105) The solid phase diffusion coefficient of lithium (D105), the anode double-layer coating region length (L1034), the length of the third anode active material layer (L105), the first anode active material layer thickness (T103), the second anode active material layer thickness (T104), and the third anode active material layer thickness (T105) are shown in table 1.
D50 particle diameter (R203) of the first positive electrode active material in the slurry for forming the first positive electrode active material layer, and exchange current density (i) of lithium in the first positive electrode active material0203) The solid-phase diffusion coefficient of lithium (D203), the D50 particle diameter of the second positive electrode active material in the slurry for forming the second positive electrode active material layer (R204), and the exchange current density of lithium in the second positive electrode active material (i)0204) A solid-phase diffusion coefficient (D204) of lithium, a D50 particle diameter (R205) of the third positive electrode active material in the slurry forming the third positive electrode active material layer, and an exchange current density (i) of lithium in the third positive electrode active material0205) Solid phase diffusion coefficient of lithium (D205), positive electrode bilayer coatingThe layout length (L2034), the length of the third positive active material layer (L205), the first positive active material layer thickness (T203), the second positive active material layer thickness (T204), and the third positive active material layer thickness (T205) are shown in table 2.
TABLE 1
TABLE 2
Test example
The cells obtained in examples 1 to 6 and comparative examples 1 to 5 were assembled into lithium ion batteries, and the capacity retention rates after 500 cycles were tested and the phenomenon of lithium precipitation at the negative electrode was observed, the tests were performed under 2C charging and 0.7C discharging conditions, and the test results are shown in table 2.
TABLE 3
Number of cycles | Capacity retention rate | Whether or not lithium precipitation occurs | |
Example 1 | 500 | 91.2% | No occurrence of lithium precipitation |
Example 2 | 500 | 94.5% | No occurrence of lithium precipitation |
Example 3 | 500 | 91.3% | No occurrence of lithium precipitation |
Example 4 | 500 | 88.5% | No occurrence of lithium precipitation |
Example 5 | 500 | 90.1% | No occurrence of lithium precipitation |
Example 6 | 500 | 89.6% | No occurrence of lithium precipitation |
Comparative example 1 | 500 | 85.6% | Slight precipitation of lithium |
Comparative example 2 | 500 | 86.8% | Slight precipitation of lithium |
Comparative example 3 | 500 | 83.2% | Separating lithium |
Comparative example 4 | 500 | 82.6% | Separating lithium |
Comparative example 5 | 500 | 76.3% | Severe lithium precipitation |
As can be seen from the test results in table 3, the lithium ion batteries assembled in examples 1 to 6 can effectively inhibit the lithium precipitation phenomenon of the negative electrode of the lithium battery, compared with the lithium ion batteries assembled in comparative examples 1 to 5, and have a higher capacity retention rate, and the capacity retention rate of the lithium battery assembled in examples after 500 cycles can be as high as 88%, even higher than 94%.
Finally, it should be noted that: the above experimental examples are only used to illustrate the technical solution of the present invention, but not to limit the same; although the present invention has been described in detail with reference to the foregoing experimental examples, it will be understood by those skilled in the art that: the technical scheme recorded in each experimental example can be modified, or part or all of the technical features can be equivalently replaced; and the modifications or the substitutions do not make the essence of the corresponding technical scheme depart from the scope of the technical scheme of each experimental example of the invention.
Claims (10)
1. A lithium battery cell is characterized by comprising a positive plate and a negative plate, wherein the negative plate comprises a negative current collector and a negative functional layer coated on at least one surface of the negative current collector, a negative tab is arranged on a first surface of the negative current collector, the functional layer on the first surface comprises a double-layer coating area close to the negative tab, the double-layer coating area comprises a first negative active material layer and a second negative active material layer, the first negative active material layer is positioned between the surface of the negative current collector and the second negative active material layer, and the particle size of a first negative active material in the first negative active material layer is larger than that of a second negative active material in the second negative active material layer;
the positive plate includes the anodal mass flow body and coats the anodal functional layer on the anodal mass flow body at least one surface, be equipped with anodal utmost point ear on the third surface of the anodal mass flow body, with the functional layer on the fourth surface that the third surface is relative is including the double-deck coating district near anodal utmost point ear, double-deck coating district includes first anodal active material layer and second anodal active material layer, first anodal active material layer is located between anodal mass flow body surface and the second anodal active material layer, the particle diameter of first anodal active material in the first anodal active material layer is less than the particle diameter of the anodal active material of second in the second anodal active material layer.
2. The lithium battery cell of claim 1, wherein the exchange current density and solid phase diffusion coefficient of lithium in the second negative active material is greater than the exchange current density and solid phase diffusion coefficient of lithium in the first negative active material; the exchange current density and solid-phase diffusion coefficient of lithium in the first positive electrode active material are greater than those of lithium in the second positive electrode active material.
3. The lithium battery cell of claim 1, wherein the first negative active material in the negative electrode sheet has a D50 particle size of R103, the second negative active material has a D50 particle size of R104, R103 is greater than or equal to 5 μm and less than or equal to 30 μm, R104 is greater than or equal to 1 μm and less than or equal to 20 μm, and R103-R104 are greater than or equal to 2 μm.
4. The lithium battery cell of claim 1, wherein the particle size of D50 of the first positive active material in the positive electrode sheet is R203, the particle size of D50 of the second positive active material is R204, R203 is greater than or equal to 1 μm and less than or equal to 28 μm, R104 is greater than or equal to 3 μm and less than or equal to 30 μm, and R204-R203 are greater than or equal to 2 μm.
5. The lithium battery cell of claim 1 or 2, wherein a ratio of an exchange current density of lithium in the second negative active material to an exchange current density of lithium in the first negative active material is not less than 1.1, and a ratio of a solid phase diffusion coefficient of lithium in the second negative active material to a solid phase diffusion coefficient of lithium in the first negative active material is not less than 1.2.
6. The lithium battery cell of claim 1 or 2, wherein the ratio of the exchange current density of lithium in the first positive active material to the exchange current density of lithium in the second positive active material is not less than 1.1, and the ratio of the solid phase diffusion coefficient of lithium in the first positive active material to the solid phase diffusion coefficient of lithium in the second positive active material is not less than 1.2.
7. The lithium battery cell of claim 1, wherein the negative electrode functional layer further comprises a first normal coating region remote from the negative electrode tab and contiguous with the double-layer coating region, the first normal coating region being formed from a single layer of a third negative electrode active material layer, the sum of the capacity per unit area of the first negative electrode active material layer and the capacity per unit area of the second negative electrode active material layer being no less than the capacity per unit area of the third negative electrode active material layer; the positive electrode functional layer further comprises a second normal coating area which is far away from the positive electrode lug and connected with the double-layer coating area, the second normal coating area is formed by a single-layer third positive electrode active material layer, and the sum of the unit area capacity of the first positive electrode active material layer and the unit area capacity of the second positive electrode active material layer is not less than the unit area capacity of the third positive electrode active material layer.
8. The lithium battery cell of claim 7, wherein both surfaces of the negative current collector are coated with a negative functional layer, and wherein the functional layer of the second surface opposite the first surface comprises a third normal coating region that is mirror symmetric to the first normal coating region, the third normal coating region being formed from a single layer of a third negative active material layer; two surfaces of the positive current collector are coated with positive functional layers, the functional layers of the third surface opposite to the fourth surface comprise a fourth normal coating area which is mirror symmetric with the double-layer coating area and the second normal coating area, and the fourth normal coating area is formed by a single-layer third positive active material layer.
9. The lithium battery cell of claim 1, wherein the cell is a wound cell, the first negative active material layer in the negative electrode sheet has a length of L103, the second negative active material layer has a length of L104, the winding core has a width of W, 0.5W ≤ L103 ≤ 3W, 0.5W ≤ L104 ≤ 3W, the first positive active material layer in the positive electrode sheet has a length of L203, the second positive active material layer has a length of L204, the winding core has a width of W, 0.5W ≤ L203 ≤ 3W, and 0.5W ≤ L204 ≤ 3W.
10. A lithium ion battery comprising the wound cell of claim 9.
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Citations (14)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
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 |
CN109244475A (en) * | 2018-11-05 | 2019-01-18 | 宁德新能源科技有限公司 | Electrochemical appliance and electronic device comprising it |
CN109461882A (en) * | 2018-11-05 | 2019-03-12 | 宁德新能源科技有限公司 | Anode pole piece, electrochemical appliance and the electronic device comprising it |
CN110867560A (en) * | 2018-08-28 | 2020-03-06 | 宁德时代新能源科技股份有限公司 | Negative pole piece and secondary battery |
CN111029527A (en) * | 2019-12-11 | 2020-04-17 | 宁德新能源科技有限公司 | Negative electrode, and electrochemical device and electronic device including the same |
CN111129502A (en) * | 2018-10-31 | 2020-05-08 | 宁德时代新能源科技股份有限公司 | Negative pole piece and secondary battery |
CN111540879A (en) * | 2020-05-08 | 2020-08-14 | 珠海冠宇电池股份有限公司 | Positive plate, preparation method and lithium ion battery comprising positive plate |
CN111540881A (en) * | 2020-05-08 | 2020-08-14 | 珠海冠宇电池股份有限公司 | Negative plate, preparation method and lithium ion battery comprising negative plate |
CN111725484A (en) * | 2020-06-12 | 2020-09-29 | 珠海冠宇电池股份有限公司 | Negative plate, preparation method and battery |
CN111785923A (en) * | 2020-07-31 | 2020-10-16 | 蜂巢能源科技有限公司 | Lithium ion battery anode, preparation method and application thereof, and lithium ion battery |
CN111916667A (en) * | 2020-07-27 | 2020-11-10 | 珠海冠宇电池股份有限公司 | Negative plate and lithium ion battery comprising same |
CN111916666A (en) * | 2020-07-27 | 2020-11-10 | 珠海冠宇电池股份有限公司 | Negative plate with special-shaped structure and lithium ion battery comprising same |
CN111969214A (en) * | 2020-08-19 | 2020-11-20 | 珠海冠宇电池股份有限公司 | Positive plate with special-shaped structure and lithium ion battery comprising same |
CN212209657U (en) * | 2020-06-11 | 2020-12-22 | 珠海冠宇电池股份有限公司 | Battery negative plate and battery roll core |
-
2020
- 2020-12-29 CN CN202011597847.4A patent/CN112750976B/en active Active
Patent Citations (14)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
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 |
CN110867560A (en) * | 2018-08-28 | 2020-03-06 | 宁德时代新能源科技股份有限公司 | Negative pole piece and secondary battery |
CN111129502A (en) * | 2018-10-31 | 2020-05-08 | 宁德时代新能源科技股份有限公司 | Negative pole piece and secondary battery |
CN109244475A (en) * | 2018-11-05 | 2019-01-18 | 宁德新能源科技有限公司 | Electrochemical appliance and electronic device comprising it |
CN109461882A (en) * | 2018-11-05 | 2019-03-12 | 宁德新能源科技有限公司 | Anode pole piece, electrochemical appliance and the electronic device comprising it |
CN111029527A (en) * | 2019-12-11 | 2020-04-17 | 宁德新能源科技有限公司 | Negative electrode, and electrochemical device and electronic device including the same |
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