Methods and related systems conduct a capacity check of a battery via a partial discharge cycle. A method of estimating a total capacity of a battery includes partially discharging the battery at a controlled discharge rate so as to discharge an amount of energy from the battery over a period of time. An output voltage of the battery is measured during the period of time. A total capacity of the battery is estimated based on the amount of energy discharged from the battery during the partial discharge cycle and the output voltage of the battery measured during the partial discharge cycle.