Cylindrical lithium ion battery roll core center pin and battery

Abstract

The invention discloses a cylindrical lithium ion battery roll core center pin and a battery, and belongs to the technical field of storage batteries, the cylindrical lithium ion battery roll core center pin is characterized by comprising a strip-shaped body made of a shape memory material, and the strip-shaped body is of a hollow structure; in an initial state, the outer diameter of the strip-shaped body is smaller than the inner diameter of a central hole of a battery roll core; and after the battery is heated and recovered, the outer wall of the strip-shaped body is attached to the inner wall of the central hole of the battery roll core. The central needle is made of the shape memory material, is hollow or approximately hollow before being inserted into the roll core, and is a thin-strip-shaped alloy rod, so that the central needle can be conveniently inserted into the central hole of the roll core in the production process, and the defect that the interior of the roll core is damaged due to overlarge diameter in the insertion process of the central needle can be effectively avoided. And in the heating process of the battery, the central needle can recover to a cylindrical structure with a certain diameter and is tightly attached to the roll core, so that the interior of the roll core is effectively supported, and the roll core is prevented from collapsing inwards.

Description

technical field [0001] The invention belongs to the technical field of accumulators, and in particular relates to a cylindrical lithium-ion battery rolling core center pin and the battery. Background technique [0002] As an energy storage system, cylindrical lithium-ion batteries have the characteristics of mature technology, high production efficiency, and strong reliability. They have broad application prospects in civil, aviation, aerospace, military communications, and combat fields. In recent years, with the continuous upgrading of military and civilian energy storage systems, higher requirements have been placed on the cycle life of lithium-ion batteries. Cylindrical lithium-ion battery cores are usually hollow structures, but during battery cycle use, the hollow structure of battery cores has the risk of internal collapse due to expansion of the core. [0003] In order to improve the cycle reliability of cylindrical lithium-ion batteries, some batteries introduce a ...

AI Technical Summary

Problems solved by technology

In CN214043758U, it is mentioned that the technology of pasting expansion tape on the outside of the center needle is improved, but the expansion tape has a loss to the free electrolyte, which is not conducive to the full infiltration of the electric core, and there is the possibility of uneven expansion; expansion after using the expansion tape to absorb liquid is harmful to the The inside of the cell is not rigidly supported, which cannot effectively restrain the internal deformation of the cell

Therefore, in the prior art, the inside of the battery core still has the risk of inward collapse

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