INTERNAL BATTERY PRESSURE MEASUREMENT METHOD, INTERNAL BATTERY PRESSURE MEASUREMENT PROGRAM, INTERNAL BATTERY PRESSURE MEASUREMENT DEVICE, AND INTERNAL BATTERY PRESSURE MEASUREMENT SYSTEM

PROBLEM TO BE SOLVED: To measure pressure in a battery (internal pressure) by nondestructive means with high accuracy in a battery containing an electrode, electrolyte, and coil in its hermetically sealed package.SOLUTION: A charge/discharge control method is provided which comprises: a charger management process in which a total amount of discharges from a charger is calculated and determination of whether the total amount exceeds a predetermined value is made; and a storage battery management process in which, when determined to be equal to or greater than the predetermined value by the charger management process, a differential time between a storage battery which is finished charging first in time series and a storage battery which is finished charging last in time series is calculated, a predicted charge time from a total amount charged to the storage battery which is finished charging last in time series and from the differential time is calculated, and an upper limit to the amount of discharges from a storage battery device from the predicted charge time and from the stored amount of power in the storage battery device is set.