Parallel connection - Connection together of the cell terminals of the same polarity of two or more cells to form a battery of higher capacity.
Permanent charge - The charging current which can safely be continuously supported by the battery, regardless of the state of the charge.
Peukert’s equation - An empirical formula that approximates how the available capacity of a battery changes according to the rate of discharge. The equation shows that at higher currents, there is less available energy in the battery.
Photovoltaic cell - A device that directly converts the energy in light into electrical energy. Also called a photocell, a solar cell or a PV cell.
Pilot Cell - A selected cell whose condition is assumed to indicate the condition of the entire battery.
Polarity reversal - Reversal of the polarity of a battery or cell due to over discharge.
Primary battery - A battery that is non-rechargeable.
Pulse charger - Versatile, hybrid charger having some of the advantages of both switch-mode and linear chargers. More costly than both.
Pulse discharge - A high rate discharge, usually of 1 second or less.