Electric capacity balancing module of electrothermic battery capable of increasing battery balancing speed and maximizing available space of vehicle body

An electric capacity balancing module of electro thermic battery comprises a battery unit, a plurality of electric heating sheets, a balance control switch unit, a plurality of heating control switches, and a controller. The battery unit includes a plurality of battery strings. The electric heating sheets are disposed among the battery strings at intervals. The balance control switch unit is electrically connected with the battery strings and has a common terminal. The common terminal is electrically connected with the electric heating sheets. Each heating control switch is connected in series with each electric heating sheet. When determining that the voltage of any battery string is different from the voltage of other battery strings, the controller controls the switch status of the balance control switch unit and the heating control switches, so as to constitute a balance loop with a portion of the battery strings and a portion of the electric heating sheets.