Battery remaining capacity measuring apparatus

摘要

A remaining capacity operation portion 19 provides an approximate linear function (I=aV+b) having a voltage-current characteristic by a method of least squares according to an open circuit voltage when a load 1 is disconnected to a battery 3, a closed circuit voltage when a battery 3 is connected to a load 1 which is detected for every predetermined time and a current passing through a load, where a reference value (I<0) is substituted in this approximate linear function, which a display portion 27 displays as an remaining capacity voltage.