Active cooling system for electrochemical cells

Abstract

An active cooling system (40, 41) for cooling electrochemical cells (11) that are arranged in a stack (9) in a fuel cell or battery (3). The cooling system (40, 41) comprises cooling panels (15, 16) carrying a cooling fluid that flows adjacent to, and parallel to the plane of, each cell (11). The rate of cooling fluid flow past each cell (11) is made to be substantially equal, so that each cell (11) experiences substantially the same cooling environment, adding to the longevity of the fuel cell or battery (3). This can be accomplished by equalizing the resistance to cooling fluid flow for each cooling path (12), e.g., by using pressure equalizing, monotonically increasingly sized orifices (28) in an input manifold (25). Dual cooling panels (15, 16) are preferably employed, in a counterflow mode. The panels (15, 16) may be divided into parallel channels (33). Heat pipe panels (35) containing a two-phase fluid may be used in lieu of panels (15, 16) that contain cooling fluid in a single state.