IMBALANCE DETERMINATION CIRCUIT, IMBALANCE REDUCTION CIRCUIT, BATTERY POWER SUPPLY, AND IMBALANCE EVALUATION METHOD

摘要

PPROBLEM TO BE SOLVED: To provide an imbalance determination circuit, an imbalance reduction circuit, a battery power supply, and an imbalance evaluation method, for improved precision in evaluating whether imbalance has occurred in an amount of accumulated energy in each of a plurality of secondary batteries. PSOLUTION: The imbalance determination circuit includes the first voltage acquisition part 333 which acquires a terminal voltage of each secondary battery as the first voltage of each secondary battery when a battery pack 40 stops discharging, a timer circuit 339 which clocks an elapse of time after stopping discharging, the second voltage acquisition part 334 which acquires a terminal voltage of each secondary battery as the second voltage of each secondary battery when an elapse of time amounts to a set time ts or more, a voltage change amount calculating part 335 which calculates a difference between the first voltage and the second voltage corresponding to each secondary battery as a voltage change amount, and an imbalance evaluation part 336 which determines that an imbalance has occurred when at least one of the differences between voltage change amounts calculated by the voltage change amount calculating part 335 exceeds an evaluation threshold set in advance. PCOPYRIGHT: (C)2010,JPO&INPIT