Abstract: A controller identifies a condition of a hazardous internal short by comparing patterns of series element voltages to the last known balance condition of the series elements. If the loaded or resting voltage of one or more contiguous series elements uniformly drop from the previously known condition by an amount consistent with an over-current condition, an over-current internal short circuit fault is registered. The desired response is to prevent the affected series elements from heating to a hazardous temperature by summoning the maximum heat rejection capability of the system until the short ceases and the affected elements cool, the cooling function is no longer able to operate due to low voltage, or the affected series string has drained all of its energy through the short. Also includes are responses that allow the battery pack to continue to power the cooling system even though it may enter an over-discharged state.

Abstract: A battery coolant jacket for use with a plurality of cells is provided, the jacket comprised of a hollow enclosure configured to permit a liquid coolant to flow through the enclosure, entering via a coolant inlet and exiting via a coolant outlet; a plurality of cell apertures that extend completely through the hollow enclosure, where each cell aperture is sized to fit a cell; and a plurality of coolant segregation walls that are integrated into the hollow enclosure and separate the cells into groups of cells, and where each coolant segregation wall forms a barrier between the cell group contained within that coolant segregation wall and the liquid coolant flowing through the hollow enclosure. The coolant jacket may include at least one flow control wall integrated within the hollow enclosure that controls the coolant flow pathway between the enclosure's coolant inlet and outlet, for example causing the coolant flow pathway to alternate directions between adjacent cell groups.