EXISTALITE BTF-114 Compatible Battery 2.4V 2000mAh Ni-MH

EXISTALITE BTF-114 — 2.4V Ni-MH Replacement Battery

This 2.4V 2000mAh Ni-MH cell replaces the internal battery in the EXISTALITE BTF-114 emergency lighting unit. It restores backup power to exit signs and emergency fixtures when the original cell has degraded past its rated capacity. Fit models confirmed: BTF-114 and BTF114.

• BTF-114 cell compatibility: Both BTF-114 and BTF114 references name the same fitting. The 2.4V Ni-MH chemistry matches the charge controller's float voltage and current profile built into this unit — swapping to a different voltage or chemistry will cause charge faults or overcharge damage.
• Bench tested on actual hardware: We ran this cell through a full charge cycle and simulated mains failure. The BMS accepted the cell without fault, and the fitting activated on cue. The charge indicator stepped through amber to green as expected over the conditioning window.
• First test cycle after installation: Within 24 hours of fitting, hold the test button for the full rated duration. This confirms the new cell accepts load and lets the charge controller register the actual capacity before your next scheduled compliance test — skipping this step risks a failed duration test that isn't a battery fault.

Emergency light failing its duration test after battery replacement

A freshly installed Ni-MH cell does not arrive at full capacity. Ni-MH cells stored in a warehouse operate at reduced capacity until they complete one or two full charge-discharge cycles. The BTF-114's charge controller begins a slow trickle charge the moment the cell is connected, but 24 to 48 hours must pass before the cell reaches its rated 2000mAh. Running a formal compliance test before that window closes will produce a shorter-than-rated duration — the cell is not defective, it is simply unconditioned.

Charge indicator staying red after new cell installation

The BTF-114's charge controller checks cell voltage before entering float charge. A cell that has self-discharged below roughly 1.9V during storage falls outside the controller's float acceptance window, so it holds the red fault state instead of transitioning to amber or green. Leave the fitting powered on mains for at least 48 hours — the controller will run a recovery charge pulse and re-evaluate the cell once it climbs back above 2.1V. If the indicator stays red after 72 hours of continuous mains power, measure across the cell terminals and confirm voltage is rising; anything climbing toward 2.4V is charging correctly.