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ENERGY MANAGEMENT SYSTEMS
W per cell or 4 kW for the whole battery. is is in addition to the
heat generated by the electrochemical reactions in the cells.
As a cell ages, the resistance of the electrolyte tends to increase.
Aging also causes the surface of the electrodes to deteriorate; the
contact resistance builds up and, at the same, the effective area of the
platesdecreases, reducing its capacitance. All of these effects increase
the internal impedance of the cell, adversely affecting its ability to
perform. Comparing the actual impedance of a cell with its imped-
ance when it was new can be used to give a measure or representation
of the ...