Mobile Phone and PDA Batteries by the battery specialists.
As
one of the UK’s largest stockists of compatible mobile phone batteries we are able to offer an unrivaled selection of models to supply new life to your communications. Carry a spare battery and never be caught out without power.
Notes and useful information regarding Mobile phone batteries.
The battery is the energy source of your mobile phone. With a flat battery, it is of little use, and one of the biggest curbs on mobile phone use is the battery life.
Mobile phone designers try hard to minimise the power they use, which then gives longer service from smaller, lighter batteries, but although the power used on standby drops through good design,
the power needed for the transmitter does not. A phone with a week or more of standby time may still only manage an hour or two of calls before its battery is flat.
Primary cells
Some handsets can take primary (non-rechargable) batteries. This can be useful in an emergency, but if you do it regularly, the battery costs will be astronomical. Some handsets nearly manage to take "ordinary" batteries. For example, the Motorola
c520 works with 4 AA batteries, but the standard battery cover won't then fit.
Rechargeable battery types
There are three main basic types of rechargeable battery used in mobile phones.
Nickel Cadmium (NiCd)
This is the rechargeable battery with which most people are familiar. This is a technology that has been around for many years, and rechargeable NiCd batteries are (or
were) common. They have two major drawbacks, which mean that most quality mobile phones no longer use NiCd batteries:
Heavy meta.l The chemicals in Nickel Cadmium are not environmentally friendly, and the disposal of cadmium-rich waste is a problem.
Memory effect.
This is sometimes referred to as voltage depression. If you do not fully discharge a NiCd cell before recharging it, after a few cycles, the battery "learns" this low mark, and acts as if it is discharged at this point.
The work-around is simple: you have to run the cell down before recharging it. Unfortunately, it is not always convenient to do this. You want the phone to be available for use, not sitting running the battery down. In addition, the cells are connected in
series, so although some cells may be discharged, others may not be.
There are specialist battery conditioners which claim to cure this problem. Some of them even work.
Nickel Metal Hydride (NiMH)
Nickel Metal Hydride batteries are superior to NiCd not only because they don't contain cadmium. They are also are less prone to the "memory effect" problem, and a discharge every week or so is ample, unlike NiCd which need
to be run down every other charge to retain their capacity. They also have a higher capacity in relation to their size and weight
The drawback of NiMH is that they would appear not to last as long as NiCd cells. After a few hundred charge cycles, the crystals inside NiMH cells become coarser, and although they are able to provide the power for long standby times, when the extra current to sustain a call is needed, the voltage available drops rapidly, and suddenly you get Low Battery
warnings. End the call, and after a few minutes rest, the battery is fine for many hours standby.
Lithium Ion (Li-Ion)
This is the current technology for mobile phone batteries. Li-Ion gives exceptional capacity for its size and weight, and does not suffer from the memory effect. This means that you can top up the charge whenever it is convenient. The only real drawback of Li-on is that they are expensive, and so they tend to
be supplied only in top-of-the-range phones. You should avoid completely discharging Li-Ion batteries
There are also Lithium Polymer batteries, but these are very similar to Lithium Ion, except that they can be moulded into more varied shapes, and so be squeezed into smaller phone casings. They can also be lighter still.
