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Nickel Cadmium (NiCd)

Among rechargeable batteries, the NiCd remains a popular choice for two

way radio applications and is one of the most rugged rechargeable batteries

available. The NiCd prefers a fast charge to a slow charge. This battery is a

strong, silent worker and hard labor poses no problem BUT it should not

be left in a charger for days or be used only occasionally for brief periods.

A periodic FULL discharge is very important. If this does not occur, large

crystals form on the cell plates, thus decreasing battery capacity and

performance.

NiCd Advantages:

•

Fast and simple charge – even after prolonged storage.

•

High number of charge/discharge cycles – if properly maintained

over 1000 cycles are possible.

•

Allows recharging at low temperatures.

•

Long shelf life in any state of charge.

•

Good low temperature performance.

•

Economically priced.

NiCd Limitations:

•

Develops memory eﬀ ect.

•

Relatively high self-discharge rate during storage.

The modern NiMH battery oﬀ ers up to 40% higher energy density as

compared to the NiCd. Both NiCd and NiMH batteries have high self-

discharge rates. The NiCd loses about 10% of its capacity within the ﬁ rst

24 hours, after which the rate settles to about 10% per month. The self-

discharge rate of the NiMH battery is about one and a half to two times

greater compared to NiCd. This type of battery is widely accepted to be the

interim step to lithium battery technology.

NiMH Advantages:

•

30-40 % higher capacity than a standard NiCd.

•

Less prone to memory eﬀ ect than the NiCd — periodic cycles are

required less often.