Battery Backup 6 Volt Nickel–Metal Hydride (NiMH) Red Letter Battery Backup
Battery Backup
Products with battery backup contain a battery so in the case of a power outage the lights or signs with stay illuminated for roughly 90 minutes.Red Letter
New York City and Chicago require exit signs to have red letters6 Volt
6 VoltNickel–Metal Hydride (NiMH)
NiMH batteries can have two to three times the capacity of an equivalent size NiCd, and their energy density approaches that of a lithium-ion cell. Nickel–Metal Hydride batteries are good for high current drain applications because of their low internal resistance.
The disadvantage of NiMH batteries is their high rate of self-discharge. NiMH batteries typically lose 4% of their charge per day of storage. LSD NiMH batteries significantly lower self-discharge, but at the cost of lowering capacity by about 20%.