COOLING SYSTEM IN A FUEL CELL ELECTRIC VEHICLE AND METHOD OF CONTROLLING A COOLING SYSTEM IN A FUEL CELL ELECTRIC VEHICLE

A cooling system in a fuel cell electric vehicle comprising a first chamber configured to contain relatively hot fluid and a second chamber configured to contain relatively cold fluid. The ratio of cooling power/fan power of a positive displacement device at a heat exchanger is monitored and thermal energy transfer between coolant and the chambers is controlled based on the ratio. When the ratio is above a pre-defined value or value range, thermal energy from the first chamber is provided to the coolant in the coolant circuit and passed into the heat exchanger, after which part of the thermal energy of cooled coolant leaving the heat exchanger is provided to and stored in the second chamber. The stored cold thermal energy is released from the second chamber when the ratio is below the pre-defined value or value range. The invention also relates to a method of controlling a cooling system.