Its main drawback is the memory oddity it exhibits, where over time it can hold less and less of a charge. This can be avoided by draining the battery completely before charging it again.
Most of the other types of rechargeable batteries in use today are variations of the traditional nickel cadmium battery that are able to hold more charge, hold charge for longer and / or deliver more voltage over a given period of time. There has also been an effort to turn away from batteries that suffer from the battery capacity memory effect that nickel cadmium batteries do.
The nickel metal hydride battery has some great advantages over the more traditional nickel cadmium battery. It holds a stronger charge and for a longer period of time. Supposedly the nickel metal hydride doesn’t suffer memory battery capacity problems, but not everyone agrees that there is no capacity loss over time.
More recently, lithium batteries are superseding nickel based batteries. The lithium polymer battery holds a greater charge for a much longer period of time (two to three times as long, even for power hogs like digital cameras) and can come in may more shapes than traditional nickel batteries.
All lithium batteries can be shaped into unique forms because the internal cells are plastic pouches that are flexible, rather than the hard metal casing of the internal cells of traditional nickel based batteries.
Lithium ion batteries are a notch up from lithium polymer batteries and have a very high charge density. For portable rechargeable equipment and devices these are the best you can get. They are not affected by loss of capacity over time and provide a consistent supply of energy.
Lithium batteries cost as much as three times nickel metal hydride batteries. If you really don’t like how the lithium battery prices look up against your personal finances, then opt for the metal hydride. If you’re used to Ni-Cad batteries you’ll notice a difference without paying the exorbitant amount that lithium batteries demand. Plus, when it’s time to spring for the lithium battery you can rotate between the two and increase the lifespan of both of them.
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