Self-discharging screening method of lithium ion battery

Abstract

The invention provides a self-discharging screening method of a lithium ion battery. The method comprises the following steps: step 1: pre-charging a battery to be screened to be in a full or half state; performing high-temperature aging treatment and storing at constant temperature; marking detection open-circuit voltage as OCV1 and storing at constant temperature; marking detection open-circuit voltage as OCV2; calculating a voltage critical value U0 in the same phrase, wherein the battery with the condition that OCV2 is less than U0 is a serious self-discharging battery; and step 2: removing the self-discharging battery by using a 3o circulating way based on voltage pressure before / after the laying-aside of the battery removed in the step 1 in a full-charge state or a half-charge state. According to the self-discharging screening method of the lithium ion battery, the battery is screened after the battery is laid aside in the full-charge state or the half-charge state and the open-circuit voltage is determined, and the corresponding self-discharging batteries are removed by using the 3o circulating way, so that the self-discharging screening of the lithium ion battery is realized.

Description

technical field [0001] The invention relates to a self-discharge screening method of lithium ion batteries. It is especially suitable for the self-discharge selection of lithium-ion batteries in a full (half) electric state. [0002] Background technique [0003] Lithium batteries have the characteristics of high specific energy, low self-discharge rate, good high and low temperature performance, long charge and discharge life, and no memory effect. At present, it is widely used in notebook computers, video cameras, digital cameras, personal digital assistants (PDA), mobile communication terminal products and electric tools and other products. Many products need to use multiple cells in series or in parallel to achieve higher output voltage and capacity. The capacity, internal resistance, self-discharge rate and other properties of each batch of batteries are different in the process and preparation process. The screening of single cells with basically consistent perform...

AI Technical Summary

Problems solved by technology

The screening of single cells with basically consistent performance is the key link in the composition of battery packs, among which the screening of single self-discharge batteries is very important. However, the current selection method for lithium-ion self-discharge is complicated and has a high rate of misjudgment. Therefore, a A simple and accurate self-discharge screening method can reduce shipment risk and improve product quality for lithium battery manufacturers

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