Method for judging health degree of batteries

Abstract

The invention provides a method for judging the health degree of batteries. The method includes the first step of obtaining the voltage of battery cells in a battery pack at the terminal stage of charging in an online real-time mode; the second step of calculating the serial numbers of the first group of battery cells with the highest voltage in an online real-time mode and storing the serial numbers; the third step of calculating the serial numbers of the second group of battery cells with the lowest voltage at the current in an online real-time mode when the voltage of certain battery cells is smaller than a voltage threshold value at the terminal stage of discharging; the fourth step of comparing the stored serial numbers of the first group of battery cells and the serial numbers of the second group of battery cells, and determining the battery cells with the same serial numbers in the serial numbers of the first group of battery cells and the serial numbers of the second group of battery cells to be the battery cells with the smallest capacity relative to other battery cells. According to the method, the online dynamic judging of the health degree of the batteries when a vehicle runs can be achieved, early warning can be carried out when the health degree of the batteries is too low, the overuse of the batteries is avoided, and the batteries can be used safely and reliably.

Description

technical field [0001] The invention relates to the field of batteries, in particular to a method for judging battery health. Background technique [0002] With the development of the electric vehicle industry, lithium-ion power batteries as the power source of electric vehicles have also been more and more widely used. Lithium-ion batteries need to be matched with capacity and internal resistance before installation, but in the process of use, as the use time of lithium-ion batteries increases, due to differences in battery pole pieces and internal structures, the consistency of batteries will change. Poor, the capacity of individual single cells decays quickly or the internal resistance increases greatly. [0003] Under the condition that the usage requirements of the vehicle remain unchanged, as time goes by, the single battery will not be able to meet the energy requirements of the entire vehicle because the capacity of the single battery decays too quickly or the inter...

AI Technical Summary

Problems solved by technology

However, this method cannot meet the requirements for judging the health of a single battery, and the management and use of batteries using this method are still in a blind state

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