(WO9424716-A1)      The exchanging apparatus includes a working fluid and a structure for exchanging heat between the working fluid and an external environment. The structure includes a wall element having an external surface exposed to the external environment and an internal surface exposed to the working fluid so that heat can be exchanged between the environment and the working fluid by conductive heat transfer through the wall element. A reservoir element provides a reservoir for the working fluid and a distribution element for providing the working fluid along the wall element to provide isothermal heat exchange between the working fluid and the external environment.    The structure can be a double lumen tubular structure having an inner lumen which provides a reservoir for the working fluid, and a lumen where heat is exchanged between the working fluid and an external environment. The inner tube can be a porous structure with several pores that uniformly distribute the working fluid to the outer lumen.    USE -   Electrochemical energy system, e.g. fuel cells.    (JP8510352-W)      The exchanging apparatus includes a working fluid and a structure for exchanging heat between the working fluid and an external environment. The structure includes a wall element having an external surface exposed to the external environment and an internal surface exposed to the working fluid so that heat can be exchanged between the environment and the working fluid by conductive heat transfer through the wall element. A reservoir element provides a reservoir for the working fluid and a distribution element for providing the working fluid along the wall element to provide isothermal heat exchange between the working fluid and the external environment.    The structure can be a double lumen tubular structure having an inner lumen which provides a reservoir for the working fluid, and a lumen where heat is exchanged between the working fluid and an external environment. The inner tube can be a porous structure with several pores that uniformly distribute the working fluid to the outer lumen.    USE -   Electrochemical energy system, e.g. fuel cells.    (EP694216-B1)      The exchanging apparatus includes a working fluid and a structure for exchanging heat between the working fluid and an external environment. The structure includes a wall element having an external surface exposed to the external environment and an internal surface exposed to the working fluid so that heat can be exchanged between the environment and the working fluid by conductive heat transfer through the wall element. A reservoir element provides a reservoir for the working fluid and a distribution element for providing the working fluid along the wall element to provide isothermal heat exchange between the working fluid and the external environment.    The structure can be a double lumen tubular structure having an inner lumen which provides a reservoir for the working fluid, and a lumen where heat is exchanged between the working fluid and an external environment. The inner tube can be a porous structure with several pores that uniformly distribute the working fluid to the outer lumen.    USE -   Electrochemical energy system, e.g. fuel cells.