Charging strategy making method for improving battery circulation

Abstract

The invention discloses a charging strategy making method for improving battery circulation. The charging strategy making method for improving battery circulation comprises the following steps that phase structure change and pole piece expansion change in a charging process are observed by combining XRD phase structure analysis, pole piece expansion rate and other detection means, a transformation process in a process of embedding Li ions into graphite is analyzed by combining two test methods, a corresponding charging strategy is formulated, namely, the position where the phase structure change is large and the pole piece expansion change is maximum is judged, the state is an X% state at the moment, the battery is charged by adopting high-rate current when the state is smaller than X%, and the battery is charged by adopting low-rate current when the state is larger than X%, so that Li ions cannot be separated out on the surface of the pole piece. The method is beneficial to improving the cycle life of the battery, and on the basis of not changing the original design of the battery and not increasing the material and labor cost, the cycle life is prolonged, and the method has important significance in improving the performance of the battery, saving the cost and the like.

Description

technical field [0001] The invention relates to the technical field of lithium ion battery protection, in particular to a charging strategy formulating method for improving battery cycle. Background technique [0002] With the shortage of energy and the deterioration of the environment, new energy technologies are being used and promoted more and more. Among them, lithium-ion batteries are environmentally friendly products because of their high energy density, low self-discharge, and good cycle performance. These characteristics have led to the rapid development of lithium-ion batteries. [0003] For energy-type batteries, it is generally considered that the battery's usable capacity decays to 80% of the initial capacity, which is the end of life. The life of the battery includes cycle life and calendar life. The former refers to the number of cycles that the battery cycles to the end of its life with a certain charge and discharge system, and the latter refers to the time ...

AI Technical Summary

Problems solved by technology

On the other hand, cycle tests are often time-consuming and costly. The correct evaluation of battery life can guide the production and development of lithium batteries and the battery health management system.

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