BATTERY PACK FOR MULTIPLE AND SERIES CONNECTION

摘要

PROBLEM TO BE SOLVED: To protect more battery packs for multiple and series connection than the number of cells which a conventional protection IC accommodates using the protection IC. SOLUTION: A battery pack for multiple and series connection is formed by connecting two or more cells B1 to B8 in series and further connecting control elements Q9 and Q10 for charging and discharging in series. The battery pack is provided with a plurality of protection circuits U1 and U2 which monitor the cell voltage of each of a plurality of groups into which the series-connected cells are divided for the detection of overcharge/overdischarge; and logic circuits Q1 to Q7 which OR-process the detection signals of a plurality of the protection circuits, and control circuits Q8 and Q11 which control the control elements for charging and discharging according to the outputs of the logic circuits. The cell voltage is monitored on a group-by-group basis by the protection circuits U1 and U2 to detect overcharging/overdischarging by each cell B1 to B8 and control the control elements Q9 and Q10 for charging and discharging. Thus, monitoring and protection of the battery pack for multiple and series connection are accomplished by a simple constitution using a conventional protection IC.