POWER STORING SECONDARY BATTERY CHARGE/DISCHARGE CURRENT MEASURING METHOD, REMAINING POWER AMOUNT MEASURING METHOD, AND DEVICE FOR IT

摘要

PURPOSE:To accurately measure and evaluate the residual capacity of a secondary battery with a low-cost measuring circuitry configuration without use of any high precision insulated amplifier etc. CONSTITUTION:At the time of charging and discharging a secondary battery 1, currents in different directions flowing in a charge/discharge circuit 2 are fed to a measuring circuit 5 upon putting them together as either in the positive direction or negative direction through the polarity inversion made by a polarity inverter circuit 6. The measuring circuit 5 has a measuring instrument 9 which measures the fed charging current and discharging current and determines the residual capacity of the secondary battery 1 through cumulation of the measurements.