Charging a battery incorrectly can cause damage.
NiCAD batteries are less expensive than NiMH batteries but not always the right choice for powering an electric item. The different chemical structures of the batteries means that how they hold a charge and the rate at which they discharge is dissimilar. These differences become apparent in the comparison of NiMH vs. NiCAD battery charging requirements.
Charge Rates
NiCAD batteries can handle high amperage rates for charging better than NiMH batteries. Using a high charge rate for a NiMH battery can damage or burn the battery. The lower charge rate needed by a NiMH means a longer charging time.
Discharge Rate
When in use, NiMH batteries have a slower discharge rate than NiCAD batteries, except under high amp loads. When stored, a NiMH battery will also lose its stored charge at about double the rate of a NiCAD battery, according to servocity.com.
Charger Types
NiCAD batteries require a more sophisticated charger than NiMHs. While NiMHs can use inexpensive, generic chargers the NiCAD chargers are usually brand specific, more expensive and have built-in charge monitors and automatic shut-off capabilities.
Memory Effect
NiMH batteries experience less of the memory effect common with NiCAD. With the memory effect, the battery redefines its zero discharge level to match the level at which it begins to recharge. This means that a habit of recharging the battery before it is completely dead will lessen the amount of energy the battery reads as having available, seeing only the energy from the point of charge (not the point at which the battery is empty) to the full point.
Tags: NiCAD batteries, NiMH batteries, charge rate, means that, memory effect, NiMH battery
