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Alkaline nickel battery technology originated in 1899, when Waldmar Jungner invented the
NiCd battery. The materials were expensive compared to other battery types available at the
time and its use was limited to special applications. In 1932, the active materials were
deposited inside a porous nickel-plated electrode and in 1947, research began on a sealed
NiCd battery, which recombined the internal gases generated during charge rather than
venting them. These advances led to the modern sealed NiCd battery, which is in use today.
The NiCd prefers fast charge to slow charge and pulse charge to DC charge. All other
chemistries prefer a shallow discharge and moderate load currents. The NiCd is a strong and
silent worker; hard labor poses no problem. In fact, the NiCd is the only battery type that
performs best under rigorous working conditions. It does not like to be pampered by sitting in
chargers for days and being used only occasionally for brief periods. A periodic full discharge
is so important that, if omitted, large crystals will form on the cell plates (also referred to as
'memory') and the NiCd will gradually lose its performance.
Among rechargeable batteries, NiCd remains a popular choice for applications such as twoway
radios, emergency medical equipment, professional video cameras and power tools.
Over 50 percent of all rechargeable batteries for portable equipment are NiCd. However, the
introduction of batteries with higher energy densities and less toxic metals is causing a
diversion from NiCd to newer technologies.
Advantages and Disadvantages of NiCd Batteries
Advantages
Fast and simple charge — even after prolonged storage.
High number of charge/discharge cycles — if properly maintained,
the NiCd provides over 1000 charge/discharge cycles.
Good load performance — the NiCd allows recharging at low
temperatures.
Long shelf life – in any state-of-charge.
Simple storage and transportation — most airfreight companies
accept the NiCd without special conditions.
Good low temperature performance.
Forgiving if abused — the NiCd is one of the most rugged
rechargeable batteries.
Economically priced — the NiCd is the lowest cost battery in terms of
cost per cycle.
Available in a wide range of sizes and performance options — mostNiCd cells are cylindrical.
Disadvantages
Relatively low energy density — compared with newer systems.
Memory effect — the NiCd must periodically be exercised to prevent
memory.
Environmentally unfriendly — the NiCd contains toxic metals.
Some
countries are limiting the use of the NiCd battery.
Has relatively high self-discharge — needs recharging after storage.
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