There are four different types of emergency lighting batteries. These are:
Sealed Lead Acid
These are typically larger batteries used in ‘high-drain’ applications such as emergency twinspot luminaires or multiple lamp battery systems.
Nickel Cadmium
Whilst becoming less popular, these are still a very common battery coming mainly in D-cell or C-cell size. They are typically used in older technology compact fluorescent and T8 linear fluorescent luminaires.
Nickel Metal Hydride
The smaller size of the NiMH battery (typically AA-cell size) makes it ideal for limited space applications such as T5 linear fluorescent as well as many LED luminaires.
Lithium-ion Phosphate
A relatively new technology, LED luminaires in current production are now starting to use this technology. They have a life over double that of other technologies (typically 8 years), cope will in harsher environments (i.e. freezer lighting) and are heavy duty.
When specifying a battery ensure you give the following information:
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