To improve functionality of a charging/discharging device at low cost which is capable of discharge control in the case that a discharge control means quickly senses charged state of serial connection battery blocks, and if the number of serial connection battery blocks that have been fully charged is small, and the data with higher priority are sequentially saved when backing up.
In charge control, one serial connection battery block is charged after another serial connection battery block is charged among serial connection battery blocks connected in parallel. Here, the charge control includes a function where a charge SW is connected in series to each serial connection battery block, and a charge control means controls on/off of the charge SW, with a charge completion signal of each serial battery block outputted to a discharge control means.
Tomoyasu Sakaguchi
Hiroki Naito