Charging method of power lithium ion battery by controlling polarizing voltage

Abstract

The invention relates to a charging method of a lithium ion battery, which belongs to the technical field of battery charging and can be used for computing the value change of the polarizing voltage of the battery by a calculation formula of the polarizing voltage of the battery, wherein the calculation formula is that UP=UO-UOCV-UR=UO-f(SOC)-I*Rd. The polarizing voltage is controlled to be within a certain numerical value range for ensuring that aberration produced on a charging voltage curve is invariant. The corresponding charging current of the battery in different SOC (State of Charge) and the same polarizing voltage during charging is automatically regulated so that the charging speed of the battery is controllable. On the premise of ensuring the service life of the battery, the charging method largely enhances the charging speed of the battery. Simultaneously, the charging time is shortened, thereby enhancing the utilization efficiency of the battery, reducing the quantity of standby battery packs in the replacement mode of the battery and providing conditions for the scale application of electric vehicles.

Description

technical field The invention relates to the technical field of battery charging, in particular to a charging method for a lithium ion battery. Background technique The traditional power lithium-ion battery charging methods include constant voltage and constant current charging, step-by-step lowering current charging, current limiting constant voltage charging, gradual step-down charging, gradually decreasing pulse charging, and fuzzy control charging, etc. These charging methods have deficiencies in use, and can only be compensated by selecting different charging methods according to different application occasions of the battery. For example, constant voltage and constant current charging, step-down current charging, constant voltage and current limiting charging, gradual step-down charging, and gradually decreasing pulse charging are all charging methods for lead-acid batteries. In fact, the current acceptance of power lithium-ion batteries The capacity is much better t...

AI Technical Summary

Problems solved by technology

At this time, the battery is still charged according to the empirical charging curve, which cannot match the original characteristics of the battery, and has a great impact on the service life of the battery.

However, the CC-CV charging method commonly used at present fails to consider the influence of external temperature and battery capacity, and the selection of the turning point from constant current to constant voltage is also inappropriate.

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