Charging method and device of battery

Abstract

The invention relates to a charging method of a battery. The method comprises the steps of acquiring a battery parameter, wherein the battery parameter comprises an electrode parameter of the battery;inputting a battery model expressed by ordinary differential equation according to the battery parameter; acquiring a safety charging boundary value of the battery under circulation for n times, wherein the parameter also comprises one or more of a structure parameter of the battery, a manufacturing process parameter, an electrical parameter, an electrolyte parameter, a separator parameter and athermo-physical property parameter, the safety boundary value is maximum charging current which the battery does not generate lithium separation under different states of charge (SOC) and different temperatures, n is larger than or equal to 2 but smaller than or equal to N, N is cycle lifetime of the battery, and circulation for n times is n(th) circulation selected from 0(th) circulation to N(th)circulation; and finally, acquiring maximum safety charging current value of the battery under current circulation frequency and current SOC according to the current circulation frequency, a currenttemperature, current SOC and the safety charging boundary value of the battery.

Description

technical field [0001] The present application relates to the field of battery management, in particular to a battery charging method and device. Background technique [0002] At present, lithium-ion batteries have become the main energy storage components of various mobile devices or terminals due to their advantages such as high energy density, long cycle life, and low self-discharge rate, and are also used as the main driving power source of electric vehicles. However, the charging speed of lithium-ion batteries is relatively slow, and it takes up to several hours for a single charge. With the urgent requirements of consumers for battery life, the energy density of lithium-ion batteries continues to increase, and the accompanying charging time It is also constantly increasing, which brings serious inconvenience to the use of mobile terminals such as mobile phones and electric vehicles. In view of this, the fast charging performance of lithium-ion batteries of current mob...

AI Technical Summary

Problems solved by technology

To achieve fast charging of lithium-ion batteries, the root is to increase the charging current. However, the calorific value of the battery during charging is approximately in a square relationship with the charging current, resulting in a large amount of heat generated during fast charging of the battery, which is difficult to promote.

At the same time, the higher the temperature, the more side reactions, and the worse the cycle life and safety of lithium-ion batteries

As the charging current of the lithium-ion battery increases, the polarization of the battery will increase at the same time, resulting in lithium precipitation on the surface of the negative electrode, which will affect the performance and life of the battery, and it is also easy to cause safety hazards due to short-circuit problems.

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