Management method for attenuation consistency of power batteries

Abstract

The invention discloses a management method for the attenuation consistency of power batteries. The method comprises the following steps: measuring the corresponding relationship between each impact factor and the SOH value of a power battery in advance; during the online usage of a battery system, monitoring the SOH value of each battery cell by using a battery management system, and recording the SOH change rate, temperature, charge-discharge rate and charge-discharge cutoff voltage of each battery cell; and determining whether the SOH dispersion of the power battery is greater than preset allowable SOH dispersion, and if so, carrying out comparison based on the pre-measured corresponding relationship between each impact factor and the SOH value of the power battery and the monitored relationship between the SOH value and each impact factor in use of the power battery so as to determine main parameter factors causing the increase of the SOH dispersion and adjusting the parameter setting of each impact factor in use according to the pre-measured corresponding relationship between each impact factor and the SOH value. The management method of the invention has the advantage of capability of dynamically adjusting the parameters of the battery during the use of the battery so as to minimize the dispersion of each battery cell in the battery system as much as possible and maintainthe consistency of the battery cells.

Description

technical field [0001] The invention relates to the technical field of batteries, in particular to a method for managing power battery attenuation consistency. Background technique [0002] As the main energy storage device of electric vehicles, batteries are the key components of electric vehicles, and their performance and safety characteristics directly affect the performance of electric vehicles. The performance of lithium-ion power batteries will decline during the use of electric vehicles, such as capacity decline, internal resistance increase, and self-discharge rate increase. During the life decay process of lithium-ion batteries, side reactions will occur inside, and the main consumption is the thickening of the internal passivation film, which directly leads to capacity decay and internal resistance increase; Influence and other disadvantages, and the environment of the vehicle is likely to cause imbalance among the units in the battery pack. If the estimation of...

AI Technical Summary

Problems solved by technology

Even if the batteries are completely consistent after manufacturing and sorting, during use, due to differences in charge acceptance, self-discharge rates, and temperature distribution among individual batteries, the parameters of each cell may show a divergence trend. , the dispersion of individual cells in the battery system increases, and the SOH attenuation of individual batteries intensifies, which in turn causes the failure of the entire battery group and affects the reliability of the entire battery system