Effect Of Reversal And High Temperatures On The Performance Of Ni/H/sub 2/ Cells

Controlled reversal of NUH 2 cells resulted in voltages of -0.1 19 and -1.6 V for positive- and negative-limited cells, respectively. The voltage of -1.6 V obtained for negative-limited cells could be caused by oxygen evolution on the negative electrode and hydrogen evolution on the positive electrode, and appears to be highly polarized. One major consequence of reversal is that capacity declines with extended storage. Cell capacity was found to decrease nonlinearly with increased temperature. However, the curve showed an inversion at about 50"C which was attributed to structural changes in the positive active material.