A method for improving electrochemical and shock-proofing performance of power-driven lithium ion battery

Abstract

The invention relates to a lithium ion cell, especially an electrocar power-type lithium ion. And its characteristic: firstly designing and making a box, then placing cell polar pieces in the box, using a cell cover to connect the box and fixing them and then placing in a cell case; then welding the cell cover with the cell case into an integral whole, so as to compose the good-performance power-type lithium ion cell. In producing course, thy yield of product is increased from 66% of traditional technique to 100%; the cell capacity is increased and the internal resistance is obviously reduced, the charge-discharge property of the cell is obviously improved, and the maximum pulse discharge current multiplication can reach 15 CA; the cell capacity and internal resistance distribution are relatively consistent and centralized, remarkably enhancing the property of the cell groups applied in electromobiles or electric tools.

Description

Technical field: [0001] The invention relates to a lithium ion battery, in particular to a power type lithium ion battery for electric vehicles. Background technique: [0002] The traditional assembly method of power lithium-ion batteries is to firstly assemble the positive electrode, negative electrode and diaphragm by stacking, that is, the sheet-shaped positive electrode, negative electrode and diaphragm are assembled by using the "negative electrode, diaphragm, positive electrode, and diaphragm". The units are overlapped, and a negative electrode is superimposed on the last unit. Each pole piece is connected with the current output terminal (pole) through a current collector; then the stacked battery core is wrapped with a diaphragm or tape and put into a metal or plastic casing. This assembly method has the following disadvantages: [0003] (1) Due to the looseness between the positive and negative plates of the battery, problems such as low utilization of battery act...

AI Technical Summary

Problems solved by technology

[0003] (1) Due to the looseness between the positive and negative plates of the battery, problems such as low utilization of battery active materials, poor high-current discharge capacity, large internal resistance of the battery, and large thermal effect during charging and discharging are caused;

[0004] (2) Since the thickness of the current collector of the pole piece connected to the pole is <0.02mm/pcs, it cannot bear the longitudinal pressure, and the longitudinal tension it can bear is also quite limited

The relative movement between the pos

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