Luxalite BP4S 4.8V Emergency Light Replacement Battery 4000mAh

Luxalite LPM70 / LPM80 / LPS70 Series — 4.8V Ni-CD Replacement Battery (BP4S)

This is a 4.8V, 4000mAh nickel-cadmium replacement battery for Luxalite emergency lighting fittings. It fits the LPM70, LPM80, LPS70, LPC118, and more than 20 additional Luxalite models. Voltage and cell count match the original BP4S specification exactly.

• LPM70, LPM80, LPS70, LPC118 compatibility: These fittings share a common 4.8V charge rail and the same physical cell pack format. The connector pinout and cell arrangement match across this range, so the charge controller sees no difference from the factory battery.
• Bench tested on actual hardware: We ran this pack through a full charge cycle and a simulated mains-failure load test. The BMS accepted charge without flagging a fault, and the pack held voltage under load throughout the rated test duration.
• First-cycle test requirement: Within 24 hours of fitting, hold the test button for the full rated duration. This lets the charge controller register the new cell capacity and confirms the pack accepts load before your next scheduled compliance inspection.

Emergency light failing its duration test after battery replacement

A freshly installed Ni-CD pack is rarely at full capacity straight out of the box. Storage time and partial self-discharge mean the cells need at least one complete charge-discharge cycle before they reach rated capacity. If you test immediately after fitting, the pack will cut out early — not because the battery is faulty, but because the cells have not yet been conditioned. Allow 24 hours on charge first, then run the full duration test.

Charge indicator staying red after new battery installation

The charge controller in Luxalite fittings uses cell voltage to determine charge state. A new pack that has been in storage can sit below the float acceptance window — typically under 5.4V open circuit — which the controller reads as a fault rather than a dischargeable cell. Leave the fitting on mains power for two to four hours. The trickle charge will bring cell voltage up into the acceptance window and the indicator should shift to green. If it does not move after four hours, check that the connector is fully seated and that terminal voltage at the pack measures above 4.0V.