Why do nickel cadmium batteries need to be “boost” charged?
Nickel cadmium batteries offer the highest reliability of any battery, and are more resistant to mechanical and environmental abuse than lead-acid batteries. They do, however, need special charging in order to deliver maximum performance. If a nickel cadmium battery is charged only at the float rate it will typically deliver only about 70% of its rated capacity. This is a more serious problem for high rate applications, such as engine starting, where even small reductions in capacity have a significant impact on performance. The most effective way to insure full capacity is available in a nickel cadmium battery is to periodically charge it at an elevated voltage. This can be initiated either manually or automatically, depending on the charger. Automatic equalization is easier to use, and reduces the risk of forgetting to switch back to float voltage.
