BATTERY DISCHARGE CONTROLLER

A battery discharge controller configured to control a hybrid system having first and second batteries includes a charged electric charge amount calculating section and a discharge controlling section. The discharge controlling section controls the DC/DC converter such that the first battery and the second battery are both discharged when a first reserve electric charge amount, which is a value obtained by subtracting a predetermined first lower limit electric charge amount from the charged electric charge amount of the first battery, has a positive value, a second reserve electric charge amount, which is a value obtained by subtracting a predetermined second lower limit electric charge amount from the charged electric charge amount of the second battery, has a positive value, and an absolute value of a difference between the first reserve electric charge amount and the second reserve electric charge amount is less than a predetermined threshold.