Current collector, positive electrode plate fabricated by employing same and battery cell

Abstract

The invention discloses a current collector. The current collector comprises a conductive network and polymer porous films, wherein transition regions of the conductive network are respectively arranged at a group of opposite sides of a grid region and are continued along the side edges, tab regions are arranged at an outer sides of the transition regions and are connected, the polymer porous films are respectively attached onto an upper surface and a lower surface of the conductive network, the polymer porous films cover the grid regions and transition strip regions, and holes of the polymerporous films are corresponding to connection lines on the grid regions. The invention simultaneously discloses a positive electrode plate fabricated by employing the same. A conductive coating layer and a positive electrode material layer are sequentially coated on a surface of an outer side of the current collector and at least correspondingly cover the polymer porous films, the holes of the polymer porous films are filled with the conductive coating layer, and the conductive coating layer reaches the connection lines of the grid regions. The current collector has the advantages that the structural strength, the overcurrent capability and the conductivity of the current collector and the adhesivity of the positive electrode material are improved, and the burr short-circuit probability easy to generate on the current collector on the positive electrode plate during abusing is reduced.

Description

technical field [0001] The invention relates to a lithium-ion battery, in particular to a current collector in the lithium-ion battery, and a positive pole piece and an electric core prepared by using the current collector. Background technique [0002] Lithium-ion batteries are widely used in daily life, especially in consumer and electric vehicle fields, and the safety performance of lithium-ion batteries has also attracted more people's attention. [0003] Under some abuse conditions, such as extrusion, acupuncture, impact, etc., the positive electrode sheet will be broken due to external force. Since the positive electrode sheet contains two parts, the current collector and the positive electrode active material, the ductility of the two is different. , so the current collector is exposed from the positive pole piece, and then pierces the separator and short-circuits with the negative electrode, which will cause the cell to fail. Most of the existing current collectors ...

AI Technical Summary

Problems solved by technology

[0003] Under some abuse conditions, such as extrusion, acupuncture, impact, etc., the positive electrode sheet will be broken due to external force. Since the positive electrode sheet contains two parts, the current collector and the positive electrode active material, the ductility of the two is different. , so the current collector is exposed from the positive pole piece, and then pierces the separator and short-circuits with the negative electrode, which will cause the battery to fail

Most of the existing current collectors are aluminum foil current collectors, and some improved design cells use graphite current collectors, polymer current collectors with metal particles or metal layers evaporated on the surface, etc. The existing defects are: 1. Graphite current collectors, polymeric current collectors, etc. The electrical conductivity of the collection fluid is too poor to meet the needs of the battery; 2. The polymer current collector has poor adhesion of the active material and is prone to material dropout; 3. The graphite current collector has poor processability and is easy to break. 4. Aluminum foil current collector, poor safety effect

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