Method of building battery DC inner resistance function

Abstract

The invention provides a method of building a battery DC inner resistance function. The method comprises the following steps: corresponding battery DC inner resistance data of a battery under different battery SOCs (State of Charge), multiple different charging / discharging currents and multiple different ambient temperatures are acquired; according to the acquired battery DC inner resistance data, a function of the battery DC inner resistance relative to the battery SOCs, the charging / discharging currents and the ambient temperatures is built; a heat production model, a heat transfer model and a heat dissipation model for the battery are built, and according to the heat production model, the heat transfer model and the heat dissipation model, the surface temperature of the battery is predicted in real time; and according to the function of the battery DC inner resistance relative to the battery SOCs, the currents and the ambient temperatures and the surface temperature of the battery, a function of the battery DC inner resistance relative to the battery SOCs, the charging / discharging currents and the surface temperature of the battery is built. The function relationship between the battery SOCs, the current and the surface temperature of the battery and the battery DC inner resistance can be described simply, comprehensively, accurately and in real time, realization is easy, and engineering applications are facilitated.

Description

technical field [0001] The invention relates to the technical field of batteries, in particular to a method for establishing a DC internal resistance function of a battery. Background technique [0002] In order to ensure the safe and efficient operation of the battery energy storage system, the system is equipped with a battery management subsystem to monitor the state of the power battery and predict the external characteristics of the power battery accordingly. Whether the battery management subsystem can accurately measure the external characteristics of the power battery is the key to effective battery management. [0003] At present, the external characteristic measurement technology of power battery is mainly reflected in the model acquisition technology of power battery. Common power battery models mainly include electrochemical models and equivalent circuit models. The electrochemical model can reflect the physical and chemical processes inside the power battery r...

AI Technical Summary

Problems solved by technology

However, this method only calculates the DC internal resistance curve of the power battery at an ambient temperature of 25°C, and only measures the DC internal resistance values ​​corresponding to different currents, and does not give the calculation of the DC internal resistance relative to some important changes. function of quantity (such as temperature, SOC, current, etc.)

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