DOTLUX EXITflat 5411 LiFePO4 Replacement Battery 3.2V 1800mAh

DOTLUX EXITflat / EXITmulti Series — 3.2V LiFePO4 Replacement Battery (5411, 5405)

This is a 3.2V 1800mAh LiFePO4 cell for the DOTLUX EXITflat and EXITmulti emergency exit light fittings. It replaces OEM part numbers 5411 and 5405, and also fits model references 5406 and 3177-160120. When mains power fails, this cell drives the LED panel to keep the exit sign illuminated for evacuation.

• EXITflat and EXITmulti platform fit: Both the EXITflat and EXITmulti share the same 3.2V single-cell LiFePO4 architecture, charge controller float voltage, and JST-style connector footprint — which is why one cell covers the full model range listed above.
• Bench tested on actual hardware: We cycled this cell through full charge and a load-discharge run on the EXITflat fitting. The onboard charge controller accepted the cell without fault, and the BMS held steady through the discharge curve without triggering a low-voltage cutoff prematurely.
• First test cycle after installation: Within 24 hours of fitting this cell, hold the test button for the full rated duration. This lets the charge controller register the new cell's capacity window before your next scheduled compliance inspection — skipping this step can result in a failed duration test even with a healthy cell.

Emergency light failing its duration test after battery replacement

A freshly installed LiFePO4 cell arrives in storage-state, typically sitting between 3.0V and 3.1V — below the charge controller's float acceptance threshold on some DOTLUX fittings. The controller may pass a trickle charge rather than a full charge cycle, meaning the cell never reaches rated capacity before the test is triggered. Allow the fitting at least 24 hours on mains power before running any duration test. If the cell still falls short, check terminal voltage at the connector — it should read 3.2V fully charged.

Charge indicator staying red after new cell installation

Some DOTLUX EXITflat fittings latch a fault state in the charge controller firmware when the old cell drops below a hard low-voltage floor — usually around 2.5V. Swapping the cell alone does not clear this latched fault. On most units, holding the test button for three seconds with the new cell connected and mains power live will reset the controller and allow the indicator to cycle to green. If the red LED persists after the reset, confirm the cell connector polarity is seated correctly before assuming a controller fault.