Patent ID: 8378636

Claim:
A multi-cell protection circuit, comprises: a first multi-cell protection chip and a second multi-cell protection chip, wherein each multi-cell protection chip comprises a serially connected multi-cell battery protection integrated circuit module and an expansion connection module, and input terminals of the serially connected multi-cell battery protection integrated circuit module are connected to positive and negative poles of corresponding cells, and output terminals of the serially connected multi-cell battery protection integrated circuit module are connected to interior signal input terminals of the expansion connection module; a charge control switch and a discharge control switch, wherein: expansion signal input terminals of the expansion connection module in the first multi-cell protection chip are connected to corresponding expansion signal output terminals of the expansion connection module in the second multi-cell protection chip, thereby the two multi-cell protection chips are connected together, and expansion signal output terminals of the expansion connection module in the first multi-cell protection chip are connected to the charge control switch and the discharge control switch, respectively, the second multi-cell protection chip is configured to make a second logical decision based on a status of the cells associated with the second multi-cell protection chip and export the second logical decision to the first multi-cell protection chip through the expansion signal output terminals of the expansion connection module in the second multi-cell protection chip, the first multi-cell protection chip is configured to make a first logical decision based on a status of the cells associated with the first multi-cell protection chip and the second logical decision from the second multi-cell protection chip received through the expansion signal input terminals of the expansion connection module in the first multi-cell protection chip, and control operations of the charge control switch and the discharge control switch, respectively, in accordance with the first logical decision, wherein the expansion connection module of the first multi-cell protection chip further comprises: an expansion signal processing module, configured to convert the expansion output signals of the second multi-cell protection chip to expansion input signals that can be identified by the first multi-cell protection chip; an expansion selection control signal processing module, configured to convert the expansion selection control signal of the first multi-cell protection chip into an expansion selection control signal that can be identified by the first multi-cell protection chip; a logical processing module, configured to carry out the logical decision for the interior input signals, the expansion input signals, and the expansion selection control signals; and an output stage module, configured to output an expansion output signal according to the logical decision result of the logical processing module.