Voltage equalization charging method for lithium ion battery pack

Abstract

The invention discloses a voltage equalization charging method for a lithium ion battery pack. The method is characterized by comprising a charging power supply, the lithium ion battery pack, an intelligent controller, a charging equalization control circuit and a battery voltage detection circuit, the charging power supply charges the lithium ion battery pack, the battery voltage detection circuit detects a voltage of each battery in the lithium ion battery pack and the total voltage of the battery pack, the detection result is sent to the intelligent control circuit, and the intelligent controller adjusts a working state of the circuit by adjusting a given signal of the charging equalization control circuit according to the current charging condition of the lithium ion battery pack, so mutual transfer of the electric quantity in the battery pack is realized, and equalization control of the whole charging process of the lithium ion battery pack is completed. The method is advantaged in that voltage balance control of each battery of the lithium ion battery pack is realized, energy maximization of the battery pack is realized, and the service life of the lithium ion battery pack isprolonged.

Description

technical field [0001] The invention relates to a charging method, in particular to a method for voltage equalization charging of a lithium-ion battery pack. Background technique [0002] Lithium-ion battery packs are usually made up of multiple batteries connected in series, but if the capacity of the batteries does not match, the capacity of the entire battery pack will be affected. If there is only a protection device in the charging circuit, but no voltage equalization circuit, when the capacity of a series battery does not match other batteries, the capacity of the entire battery pack will be reduced. When the battery pack is charging, when the voltage of a battery in the battery pack reaches the full charge voltage, the battery pack will be stopped charging, and at this time the other batteries have not yet reached full charge, which will cause the battery pack to be incompletely charged. When the battery pack is discharging, when the voltage of the battery with the s...

AI Technical Summary

Problems solved by technology

[0002] Lithium-ion battery packs are usually made up of multiple batteries in series, but if the capacity of the batteries does not match, it will affect the capacity of the entire battery pack

If there is only a protection device in the charging circuit, but no voltage equalization circuit, when the capacity of a battery in series does not match that of other batteries, the capacity of the entire battery pack will be reduced

When the battery pack is charging, when the voltage of a battery in the battery pack reaches the full charge voltage, the battery pack will be stopped charging, and at this time the other batteries have not yet reached full charge, which will cause the battery pack to be incompletely charged.

When the battery pack is discharging, when the voltage of the battery with the smallest capacity reaches the cut-off voltage, the entire battery pack will stop discharging, while other batteries still have remaining capacity at this time, which will make the battery pack discharge incomplete

Over time, the battery with the smallest capacity will degrade faster than the others, accelerating capacity loss over multiple charge / discharge cycles

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