Peak power prediction method considering durability influence of power battery

Abstract

The invention provides a peak power prediction method considering the durability influence of a power battery. Compared with the prior art, besides taking the highest temperature value of the batteryas a constraint, the change rate constraint and the aging constraint of the temperature of the battery are also added. Due to the fact that the temperature rise change rate of the battery can well reflect the health change condition of the battery when the battery is at any environment temperature, the health state change condition of the battery can be better reflected, the capacity loss is reduced, and the durability is improved. Besides, considering that the current multiplying power can influence the capacity fading track of the battery, the relation between the current multiplying power and the capacity fading constraint is derived from a capacity loss model, and the continuous charging and discharging peak current prediction is performed by taking a capacity fading limit value as theconstraint, so that the continuous charging and discharging peak power prediction of the battery is realized. The method is of great significance for the durability of the battery.

Description

technical field [0001] The invention relates to the technical field of a power battery system, in particular to research on a peak power prediction method of a power battery. Background technique [0002] The peak power of electric vehicles directly affects the acceleration climbing performance and regenerative braking energy recovery capability. If the peak power is too low, the energy provided by the battery will not be able to meet the needs; if the peak power is too high, it will cause irreversible damage to the battery and shorten the service life of the battery. In view of the non-direct measurement of peak power, it is very necessary to accurately predict it. [0003] At present, in the process of predicting the peak power of power batteries, the state of charge (SOC), terminal voltage, temperature and the maximum current of the battery design are mostly used as constraints to predict the peak current, so as to realize peak power prediction. . But in fact, compared...

AI Technical Summary

Problems solved by technology

Excessive temperature rise means that side reactions inside the battery occur, resulting in a reduction in the number of available lithium ions and accelerating battery aging

In addition, excessive peak current will cause some lithium ions to accumulate on the surface of the active material before the positive and negative electrodes of the battery can combine with electrons, which also causes the consumption of available lithium ions, accelerates the aging speed of the battery, and affects its warranty mileage and warranty time

It can be seen that for the improvement of battery durability, in addition to considering the conventional SOC, terminal voltage, temperature and factory current limit constraints, the temperature rise rate and aging constraints are also an important factor to be considered in the peak power prediction. However, there is still a lack of research on this aspect in the prior art

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