A SYSTEM TO RAPIDLY CHARGE DIODE ISOLATED BATTERY OPERATED DEVICES
Original Publication Date: 1993-Jun-01
Included in the Prior Art Database: 2002-Feb-13
One method to efficiently and effectively fast charge nickel cadmium and nickel hydride batteries is using multiple cycles which include periods of high forward charge current followed by short discharge pulses. This charging process is sometimes referred to as "burping the battery" or "negative pulse charging? The primary purpose of the discharge pulse is to prevent the accumulation of gas bubbles on the surface of the cell plates which reduces the plate area. Oxygen also causes the internal impedance to go up and causes hot spots to develop on the remaining exposed area. The discharge pulse acts to "burp" the battery by strip- ping the bubbles away from the plates and assist in the recombination of oxygen at the negative plates. The charge/discharge pulse cycling also helps to restore the crystal structure of the cell plates by breaking down crys- tal formations, eliminating "memory" problems.