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Nickel Cadmium
(Ni-Cad)
Ni-Cad battery is the oldest of the rechargeable
chemistries used in today's portable electronic industry. Its low cost and high
discharge rate capability make it suitable for low cost electronic applications
like games and toys as well as for high discharge applications such as cordless
power tools. Its low energy density (power-to-weight ratio) makes it undesirable
for use in equipment such as notebooks and cellular phones. Ni-Cad has a
chemistry-related problem associated with it called Memory Effect, which limits
the discharge capacity of the cell if not completely discharged during each use.
Nickel Metal
Hydride (Ni-MH)
Ni-MH is most commonly used in the cellular phone
battery, camcorder battery, laptop battery and notebook battery. A relative of
the Ni-Cad chemistry, it has improved performance in respect to the memory
effect problem, increased capacity, and therefore a higher energy density than
Ni-Cad. Operation of this chemistry at elevated temperatures decreases its cycle
life or the number of times a cell can be charged and discharged.
Lithium-ion
(Li-Ion)
The newest of the rechargeable chemistries,
Li-Ion has been in mass production since 1995. With three times the voltage per
cell as Nickel-based chemistries (3.6 V vs. 1.2 V), Li-Ion has a higher energy
density and is therefore ideal for lightweight applications. It is currently the
chemistry of choice for laptop battery, notebook battery, camcorder battery
and cellular phone battery applications. Li-Ion battery has had a history of
early production overheating related problems and is designed in a battery pack
with a Pack Control Circuit (PCC) to protect the cells from abusive conditions
such as current and voltage overcharging, high temperature, and over-discharge.
The relatively high cost of Li-Ion cells combined with the need for circuitry
makes the cost of Li-Ion battery packs higher than for other chemistries.
 TAKING
Care Of Your New Battery Pack
Normally, a new battery pack comes in a very low
charge condition and must be fully charged before use. Refer to the user manual
of your portable electronic equipment for charging instructions.
A new battery pack needs to be fully charged and
fully discharged or "cycled" as much as five times to condition them
into performing at full capacity.
Your equipment may report a fully charge
condition in as short as 10 to 15 minutes when the new battery pack is being
charged for the first time. This is a normal phenomenon especially for Nickel
Cadmium (Ni-Cad) and Nickel Metal Hydride (Ni-MH) chemistries. When this
happens, remove the battery pack and let it cool down for about fifteen minutes
then repeat the charging procedure.
"Conditioning" (fully discharging and
then fully charging) is necessary so as to maintain the optimum performance of a
battery pack, and is recommended at least once a month particularly for Ni-Cad
and Ni-MH batteries. Failure to do so could result in reduced charge capacity
and can significantly shorten the battery packs useful life. Lithium Ion
batteries do not require conditioning.
It is normal for a battery pack to get warm when
charging and during use. However, if the battery pack gets excessive hot, there
may be a problem with the portable electronic equipments charging circuit and
should therefore be checked by a qualified technician.
Rechargeable batteries undergo self-discharging
when left unused for long periods of time. This is normal particularly in the
case of Ni-MH and Li-Ion chemistries. For best results, always store a battery
pack fully charged. It should be removed from the equipment and kept in a cool,
dry and clean place.
The amount of runtime a battery pack produces
depends on the power requirements of components in your electronic equipment.
This could be the hard drive setting, screen intensity and back-lighting on
notebook computers, the liquid crystal display (LCD) screen and floodlight
feature in a video camcorder, or the tri-mode communications network of a
cellular phone. Always refer to your equipments user manual for power management
settings.
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