Current collector for lithium ion battery, and lithium ion battery

Abstract

The invention discloses a current collector for a lithium ion battery, and the lithium ion battery comprising the current collector. The existing current collector with a coating layer structure or anoptical foil structure is changed into a grid-like winding structure; the current collector comprises a single-layer or multi-layer grid-like structure formed by conductive metal wires in a winding manner; and metal wires adopted by a positive electrode current collector can be aluminum wires, titanium wires, and titanium aluminum alloy wires while the negative electrode adopts copper wires. Thewinding structure disclosed in the invention has multiple surfaces and can be in contact with an active material, so that the bonding surfaces of the active material and the current collector are enlarged, mutual gluing can be facilitated, relatively less dosage of a binder is adopted, the contact area between the active material and the current collector can be enlarged, and internal resistance is lowered; in addition, by virtue of the winding and uniformly-distributed grid-like structure, the mechanical property of the current collector is improved, the current collector can be more balancedin stress, and the processing difficulty is lowered; compared with a net-shaped structured and a punched hole-shaped current collector, the winding structure can provide higher mechanical property and has a larger contact area with the active material; and by virtue of matched application with titanium wires, the cycle performance of the battery is greatly improved.

Description

technical field

[0001] The invention relates to the technical field of lithium ion batteries, in particular to a lithium ion battery current collector and a lithium ion battery. Background technique

[0002] Lithium-ion battery current collectors such as copper foil and aluminum foil. Its function is mainly to fix the active material of the battery on the current collector, and at the same time gather the micro-current generated by the active material for external output or provide the active material with an electrochemical reaction micro-current for internal input. Therefore, the current collector should be sufficiently bonded to the active material and tightly enough.

[0003] The current collectors used in lithium-ion batteries are usually light foil collectors and coated collectors. These two collectors mainly have the following defects: the bonding performance between the collector and the active material is poor, and the amount of binder used is large. As a result, ...

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