Power battery health state assessment method and system and electric vehicle

Abstract

The present invention relates to a power battery health state assessment method. The method comprises the steps of: selecting two voltages in a battery cell charge process, and obtaining a charge capacity between the two voltages; determining a corresponding relation between the charge capacity between the two voltages and a health state, and establishing a health state estimation model accordingto the corresponding relation; and solving the health state according to the health state estimation model. The health state estimation model is simple and convenient to establish, the estimation process is small in calculated quantity, and rapid and real-time online estimation of the health state can be achieved; part of battery charge monitoring data is only needed to perform rapid and accurateestimation of the health state of the battery, and therefore, fault early warning in a sub-health state of the battery is achieved, and the power battery health state assessment method and system andthe electric vehicle provide basis for maintenance of a battery system. The present invention further provides a power battery health state assessment system and an electric vehicle.

Description

Technical field [0001] The present invention relates to the technical field of batteries, and in particular to a method and system for evaluating the state of health of a power battery, and an electric vehicle. Background technique [0002] With the increasing of energy crisis and environmental pollution problems, countries have begun to pay attention to the use and promotion of renewable green energy. In recent years, the emergence of new energy fields such as electric vehicles and energy storage has made lithium-ion batteries a hot research direction. In addition to the research on lithium-ion batteries, battery management systems are also one of the important research directions. In the research of battery management system, the state of health (SOH) of the battery system is currently one of the weakest links. The SOH estimation of the battery system is a major defect of the current battery management system, which directly affects the practicality, economy and safety of the...

AI Technical Summary

Problems solved by technology

Due to the long test time, complex and difficult modeling, or low estimation accuracy, the above methods cannot achieve real-time online estimation of the health status of single cells and the entire battery pack.

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