Device for equalizing charge of battery and method thereof

Abstract

The invention discloses a device for equalizing charge of a battery and a method thereof. The device is used for the charge of the battery comprising at least one battery pack. The battery pack is connected with a plurality of battery cells in series. The device comprises a main power supply used for the integral charge of the battery, an auxiliary power supply used for the compensating charge ofthe battery pack, a charge gating circuit used for connecting the auxiliary power supply to each battery cell in the battery pack in a gating manner, and a collection control circuit. The collection control circuit is used for collecting the voltage value of each battery cell in the battery pack and determining a to-be-equalized battery cell group according to a collection result. The to-be-equalized battery cell group comprises a battery cell in the battery pack or comprises two or more adjacent battery cells in the battery pack, and is used for controlling the charge gating circuit to connect the auxiliary power supply with the to-be-equalized battery cell group and controlling to adjust the voltage value output by the auxiliary power supply to be the charging voltage needed by the to-be-equalized battery cell group so as to charge the to-be-equalized battery cell group. The invention has low charge energy consumption and quick equalizing speed.

Description

technical field [0001] The invention relates to battery charging technology, in particular to a battery equalization charging device and method. Background technique [0002] Existing battery equalization techniques can be roughly divided into bypass method and energy transfer method. The bypass method is to add a bypass resistor to it when the voltage of a single cell is too high to release the excess energy and balance the overall voltage. This method is a complete energy loss type, and due to the bypass The heat generated by the circuit resistance cannot be applied to large-capacity batteries. This method is more common in small-capacity battery management systems, and the general bypass current is within 200mA. The energy transfer method is to transfer its energy to other lower voltage cells through the internal DC-DC (direct current) circuit when the voltage of a cell is too high. The conversion efficiency of this method depends on the DC-DC The efficiency and convers...

AI Technical Summary

Problems solved by technology

The energy transfer method is to transfer its energy to other lower voltage cells through the internal DC-DC (direct current) circuit when the voltage of a cell is too high. The conversion efficiency of this method depends on the DC-DC The efficiency and conversion algorithm of the conversion circuit, in extreme cases, if the energy of the first section of the battery needs to be transferred to the last section, almost all of its energy will be lost in the conversion circuit, and its circuit is complex and has a high failure rate, etc. Unfavorable factors also make it difficult to popularize the technology

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