Electric core structure of quadrate secondary lithium battery

Abstract

This invention relates to a core structure of a square secondary Li cell composed of a base board, a pole roll and two connecing pieces, which stitches layers of the positive or negative connection region of the pole roll at one stroke to finish electric connection by conduction sheets of the connection components, and the structure is simplified, besides, the internal impedance of the invented cell is lower obviously than the curent structure laminated by several main pads and sub-pads one by one since the layers of the conduction region are stitched directly at one stroke.

Description

technical field [0001] A battery cell structure of a square secondary lithium battery, in particular, refers to the design of the pole roll conductive connection structure of the battery core inside the secondary lithium battery. Background technique [0002] Existing square-shaped secondary lithium batteries are mostly used for low-power charging and discharging purposes, for example: US Patent No. 6844109, which is a very common low-power square-shaped secondary lithium battery structure, please refer to figure 1 As shown, wherein, the main composition of the electric core 10 includes: a pole roll 11, a plurality of positive and negative electrode conductive handles 121, 122 and two conductive sleeves 13, wherein the pole roll is usually composed of a positive layer, A separator layer and a negative electrode layer are superimposed on each other, and the pole roll forms a multi-layer structure through stacking or winding, and several positive electrodes are respectively dr...

AI Technical Summary

Problems solved by technology

[0005] However, in the above-mentioned existing square battery structure applicable to high power, the main gasket and the sub-gasket are clamped and connected with the segments of each layer of the pole roll respectively, although the existing conductive handle structure, and save the welding or forming process of the conductive handle. It is worth noting that in this battery structure, a main gasket and a primary gasket must be arranged in each pole layer of the pole roll. When the number of pole layers When it is huge, the number of the main gasket and the secondary gasket will increase relatively, which will not only lead to the increase of component cost, increase and complexity of the assembly process, but more importantly, the main gasket arranged in each pole layer will make the electrode The overall internal resistance of the core increases (contact resistance), which leads to problems of temperature rise and energy consumption, and for charging and discharging of high-capacity batteries, high contact resistance will cause the section of the pole coil to be damaged due to high temperature. Severe problems with oxidation;

[0006] It can be seen that the structural design of the existing square secondary lithium battery is obviously not perfect, and there is a need for further improvement; therefore, the research and development focus of the present invention is to aim at the existing high capacity square secondary battery The components of lithium batteries are complex, difficult to assemble, and the derived contact resistance is too high. A breakthrough improvement is made. Through the structural design of the present invention, the contact resistance of the conductive integrated structure is greatly reduced, and the structural composition is more streamlined. , in order to better meet the actual needs of high-capacity batteries

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