A control system for controlling discharging of a rechargeable battery, comprising: a rechargeable battery, a rechargeable dummy cell, a first circuit configured to discharge the battery and the dummy cell, a second circuit configured to measure the open circuit voltage (OCV d) of the dummy cell, and a control device configured to: determine the open circuit voltage (OCV d) of the dummy cell by using the second circuit, determine the maximum capacity decrement (ΔAh max) of the battery based on the determined open circuit voltage (OCV d) of the dummy cell, the control system being characterized in that the control device is configured to: discharge the battery and the dummy cell by using the first circuit, monitor the current capacity decrement (ΔAh x) of the battery which has been discharged and the voltage (V x) of the battery, and stop discharging, when the current capacity decrement (ΔAh x) of the battery exceeds the determined maximum capacity decrement (ΔAh max) or the voltage (V x) falls below a predetermined lower voltage limit (V min2), wherein the maximum capacity decrement is that amount of capacity, which still remains to be discharged until the state of charge of the battery reaches a predetermined lower limit of a predetermined state of charge using range. a rechargeable battery, a rechargeable dummy cell, a first circuit configured to discharge the battery and the dummy cell, a second circuit configured to measure the open circuit voltage (OCV d) of the dummy cell, and a control device configured to: determine the open circuit voltage (OCV d) of the dummy cell by using the second circuit, determine the maximum capacity decrement (ΔAh max) of the battery based on the determined open circuit voltage (OCV d) of the dummy cell, the control system being characterized in that the control device is configured to: discharge the battery and the dummy cell by using the first circuit, monitor the current capacity decrement (ΔAh x) of the battery which has been discharged and the voltage (V x) of the battery, and stop discharging, when the current capacity decrement (ΔAh x) of the battery exceeds the determined maximum capacity decrement (ΔAh max) or the voltage (V x) falls below a predetermined lower voltage limit (V min2), wherein the maximum capacity decrement is that amount of capacity, which still remains to be discharged until the state of charge of the battery reaches a predetermined lower limit of a predetermined state of charge using range. determine the open circuit voltage (OCV d) of the dummy cell by using the second circuit, determine the maximum capacity decrement (ΔAh max) of the battery based on the determined open circuit voltage (OCV d) of the dummy cell, the control system being characterized in that the control device is configured to: discharge the battery and the dummy cell by using the first circuit, monitor the current capacity decrement (ΔAh x) of the battery which has been discharged and the voltage (V x) of the battery, and stop discharging, when the current capacity decrement (ΔAh x) of the battery exceeds the determined maximum capacity decrement (ΔAh max) or the voltage (V x) falls below a predetermined lower voltage limit (V min2), wherein the maximum capacity decrement is that amount of capacity, which still remains to be discharged until the state of charge of the battery reaches a predetermined lower limit of a predetermined state of charge using range. discharge the battery and the dummy cell by using the first circuit, monitor the current capacity decrement (ΔAh x) of the battery which has been discharged and the voltage (V x) of the battery, and stop discharging, when the current capacity decrement (ΔAh x) of the battery exceeds the determined maximum capacity decrement (ΔAh max) or the voltage (V x) falls below a predetermined lower voltage limit (V min2), wherein the maximum capacity decrement is that amount of capacity, which still remains to be discharged until the state of charge of the battery reaches a predetermined lower limit of a predetermined state of charge using range.