Unitech BBAT0043A Emergency Light Replacement Battery 9.6V 1800mAh

Unitech BBAT0043A — 9.6V Ni-MH Replacement Battery

This is a 9.6V, 1800mAh Ni-MH replacement battery for the Unitech BBAT0043A emergency lighting unit. It fits emergency exit signs and backup lighting systems that switch to battery power when mains supply fails. Capacity is 1800mAh (17.28Wh), matching the original cell specification.

• BBAT0043A platform fit: Emergency lighting units in this range share a common 9.6V Ni-MH cell format, a defined connector orientation, and a trickle-charge controller tuned to that chemistry. Swapping chemistry or voltage triggers charge faults and duration test failures.
• Bench tested on actual hardware: We ran this cell through a full charge cycle on the BBAT0043A fitting and confirmed the charge controller accepted the new cell, advanced from red to green, and the BMS held voltage under simulated load without dropping to cutoff prematurely.
• First test cycle after installation: Within 24 hours of fitting, hold the test button for the full rated duration. This lets the charge controller register actual cell capacity and sets the baseline before any scheduled compliance test. Skipping this step leaves the controller estimating capacity from an unconditioned cell.

Charge indicator staying red after new battery installation

Ni-MH cells discharge slowly during storage. A cell sitting in a warehouse for several months can arrive below the float acceptance window of the BBAT0043A charge controller — typically around 9.0V for a 9.6V pack. When the controller sees terminal voltage outside its expected range, it holds the fault state and the LED stays red. Leave the fitting connected to mains for a full 24-hour charge cycle. If the indicator has not moved to green after that period, measure terminal voltage at the cell connector — anything below 8.5V after 24 hours indicates the cell may need a slow pre-charge or has a failed cell in the pack.

Emergency light dims partway through a duration test

Dimming during a test is not the same as failing to activate. It means the cell delivered its initial voltage but could not sustain load across the full test period. This happens when the cell was replaced but not given a complete conditioning cycle before the test was run — the controller never measured true capacity, so the cell runs out of usable charge before the rated duration ends. Run a full 24-hour charge cycle, then trigger the test again manually. A fully conditioned cell should hold output voltage above the fitting's low-voltage cutoff for the complete rated duration without dimming.