Monocase battery voltage balance method and balancer in the charging/discharging process of the dynamic battery group

Abstract

The voltage balancing method and device for every single cell of dynamic cell group during charging and discharging comprises: measuring (n) single cells in whole group with (n) voltage measuring circuits, comparing one single cell end voltage with its neighbor by a comparison circuit; if some single cell end voltage over its neighbor, outputting low-level signal from the comparison circuit to a control circuit; the latter operates the corresponding discharge relay to decrease this single cell voltage to keep consistency on end voltage of all single cells. This invention solves the problem that abnormal voltage of single cell affects whole cell group performance and life, and has wide application in cell testing system.

Description

technical field [0001] The invention relates to a single battery voltage equalization method and an equalizer in the charging and discharging process of a power battery pack. Background technique [0002] The power battery pack refers to a battery pack that can provide powerful power. It is suitable for hybrid vehicles, electric vehicles, portable radios, mobile data base stations, etc. The power battery pack is generally composed of multiple single cells connected in series. After multiple single cells are connected in series, due to the difference in the chemical properties of the single cells, there will often be unbalanced discharge of each single cell during use. The specific performance (1) When discharging, the energy of some single cells will be lower than that of other single cells, which means that its terminal voltage is lower than that of other single cells. When the voltage has not dropped to the protection voltage, the voltage of these single cells with low te...

AI Technical Summary

Problems solved by technology

The power battery pack is generally composed of multiple single cells connected in series. After multiple single cells are connected in series, due to the difference in the chemical properties of the single cells, there will often be unbalanced discharge of each single cell during use. The specific performance (1) When discharging, the energy of some single cells will be lower than that of other single cells, which means that its terminal voltage is lower than that of other single cells. When the voltage has not dropped to the protection voltage, the voltage of these single cells with low terminal voltage has dropped to the lower limit of the voltage. If the discharge continues, the battery will be permanently damaged due to over-discharge; (2) 2. When charging, the energy of some single cells is higher than that of other single cells, which means that its terminal voltage is higher than that of other single cells. If you continue to charge, the total voltage of the battery pack has not yet reached When the voltage upper limit is reached, the terminal voltage of these single cells with high terminal voltage has reached the upper limit. If charging continues, it will cause these single cells to overshoot and be damaged.

The above two situations will affect the performance of the entire battery pack, and even cause damage to the entire battery pack

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