Battery Type Information
Revised by BoatUS editors in April 2012
Do you know the difference between the various rechargeable batteries: Nickel-Cadmium (NiCad), Nickel-Metal Hydride (NiMH), and a Lithium Ion (Li-Ion) batteries? Do you care? You should; it could make the difference between, say, a handheld VHF or cell phone that works as advertised and one that goes dead too quickly.
A NiCad battery, which is the type used with most handheld VHF radios, has "memory", which means it should not be subject to shallow discharge. If you tend to use your handheld briefly and then top off the charge before the battery is completely drained, it will remember that level of dichaarge as its baseline. For example, if your battery is supposed to last for five hours and is recharged routinely after it is used one hour, it will eventually need recharging after it is used only one hour. If you diligently top off your handheld VHF NiCad every week, just to be safe, you'll be wondering why the "!@#$%" thing goes dead so quickly. So much for your good intentions.
The other two battery types, Lithium and Nickel-Metal Hydride, don't suffer from the memory effect so they can be used for ten minutes or ten hours. They also - surprise - cost more. However, you get what you pay for - a handheld VHF with a Lithium battery has a higher concentration of energy and a lower discharge rate than a comparable radio with a NiCad battery.
To end on a note of optimism, if you have a NiCad that has already developed short term memory, you can bring it back, at least most of the way back, by waiting until it is completely dead before recharging. Gradually the length of time between recharging will lengthen.
In these times of searches for alternate energy sources, there are frequent developments in the field of batteries. Always stay tuned.
Courtesy of Seaworthy Magazine
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