NLB 365 Emergency Light Replacement Battery 3.6V 2000mAh

NLB 365 — 3.6V Ni-Cd Replacement Battery (BAT-HT36-1500CL)

This is a 3.6V, 2000mAh Ni-Cd replacement cell for the NLB 365 emergency lighting unit. It slots in as a direct cell swap when the original degrades and the fitting can no longer hold charge through a full test cycle. Capacity is rated at 7.2Wh from factory.

• NLB 365 fitting compatibility: The 365 uses a single-cell Ni-Cd pack on a trickle-charge controller matched to this voltage rail. Swapping to a mismatched cell voltage causes the charge controller to either overcharge or never reach float — both shorten cell life significantly.
• Bench tested on actual hardware: We ran this cell through a full charge cycle and applied a load discharge to verify BMS acceptance. The charge controller transitioned to float as expected, and the cell held voltage under load without dropping out.
• First-cycle conditioning for emergency fittings: Perform a manual test within 24 hours of installation by holding the test button for the full rated duration. This lets the charge controller register the new cell's capacity before any scheduled compliance test is due.

Emergency light failing its duration test after battery replacement

A freshly installed Ni-Cd cell has not yet reached its rated capacity — storage partially discharges the cell, and the charge controller needs at least one full cycle to calibrate. If the fitting goes into a compliance test within hours of installation, the cell will likely cut out early. Allow a minimum 24-hour charge period before running any duration test. One full manual test cycle after that charge period is enough to condition the cell to rated capacity.

Charge indicator staying red after new battery installation

A cell arriving from storage can sit below the float acceptance window of the 365's charge controller, which keeps the indicator in fault or charge mode rather than switching to green. This is not a faulty cell — it is the controller waiting for terminal voltage to climb above its threshold. Leave the fitting on mains power undisturbed for 24 hours. If the indicator has not shifted to green after that period, check that the cell connector is fully seated and terminal voltage at the cell reads above 3.3V.