About this replacement
Lithonia 100-3-A117 — 14.4V Ni-MH Replacement Battery
This is a 14.4V, 10000mAh Ni-MH replacement cell for the Lithonia 100-3-A117 emergency lighting unit. It slots into the fitting to restore backup illumination during mains failure. If your unit is failing its duration test or the charge indicator has stopped cycling correctly, the cell has likely degraded past the point where the charge controller can maintain a usable float voltage.
- Lithonia 100-3-A117 compatibility: The 100-3-A117 runs a fixed 14.4V battery rail with a charge controller tuned to Ni-MH float characteristics. Swapping to a different voltage or chemistry trips the controller into a permanent fault state. This cell matches the original voltage, capacity, and terminal configuration so the controller resumes normal charge cycling without modification.
- Bench tested on actual hardware: We cycled this cell through a full charge and load discharge sequence. The BMS accepted charge within the expected voltage window and held load without triggering thermal cutoff. Cell temperature stayed within the normal Ni-MH operating range throughout the test.
- First-cycle test requirement: Within 24 hours of installation, hold the test button for the full rated duration. A cell shipped from storage has not yet been conditioned to the fitting's charge controller. Running one complete test cycle lets the controller register actual cell capacity before the unit logs its next compliance result.
Charge indicator staying red after fitting the new cell
The 100-3-A117 charge controller checks cell voltage before switching from bulk charge to float. A cell sitting in storage self-discharges, and if the resting voltage is outside the controller's acceptance window, it holds the red fault indicator rather than advancing to green. This is not a faulty cell — it is the controller refusing to switch modes until voltage climbs into range. Leave the fitting powered for 24 hours without pressing the test button. The controller should register green once the cell reaches the float acceptance threshold of around 16.8V across the pack.
Emergency light dims and cuts out partway through a duration test
Dimming mid-test means the cell cannot sustain the load current the fitting demands. On a new cell, this almost always points to a first-activation issue — the cell has not completed a full conditioning cycle, so usable capacity is lower than rated. This is separate from a failed duration test caused by a worn cell. Charge the new battery for a full 24-hour period before running the duration test. If the fitting still cuts out after one proper charge cycle, check terminal contact and confirm the cell voltage under no load reads at least 15.0V before starting the test.