Abstract: An energy storage system of a vehicle equipped with a regenerative braking system and comprising: a battery pack configured to power an electric traction machine and being operable according to predefined limited state of charge (SOC) limits extending from a lower limited SOC limit to an upper limited SOC limit, and predefined extended SOC limits; heat storage tank comprising heating fluid and an electrical heater; a processing circuitry configured to: in response of determining an anticipated cold start operating mode, charge the battery pack in accordance with the extended SOC limits to at least above a level corresponding to that of the upper limited SOC limit, and during subsequent operation of the vehicle and in response of that the SOC of the battery pack is above the upper limited SOC limit, power the electric heater by the regenerative braking system to heat the heating fluid of the heat storage tank.

Abstract: A battery monitoring system for a vehicle, comprising a battery having one or more cells, a housing wherein the battery is arranged, the housing has an atmosphere, wherein a ventilation valve is arranged at the housing for controlling the atmosphere in the housing, the ventilation valve comprises a first port and a second port, the first port being in fluid communication with the housing, the second port is in fluid communication with a closed expansion space arranged outside the housing, wherein a gas sensor is arranged at the atmosphere, at the ventilation valve, and/or at the closed expansion space, the gas sensor is configured to detect a gas leaking or emitting from the battery.