TOPA BBAT0063A Compatible Battery 3.6V 800mAh Ni-CD Emergency Light

TOPA BBAT0063A — 3.6V Ni-CD Replacement Battery for Emergency Lighting

This is a 3.6V, 800mAh nickel-cadmium cell that replaces OEM part BBAT0063A in emergency lighting fittings and exit sign units. It provides backup power when mains supply fails, keeping safety lighting active during a power outage. Voltage and capacity match the original cell exactly — 3.6V, 800mAh (2.88Wh).

• Emergency lighting fitment: These fittings use a trickle-charge circuit calibrated to a specific cell voltage and internal resistance. A Ni-CD cell at 3.6V matches the charge controller's float window without triggering a fault state. Swapping chemistry — to NiMH, for instance — shifts internal resistance enough to cause persistent fault indicators on many fittings.
• Bench tested on actual hardware: We cycled this cell through a full discharge and timed recharge on a 3.6V Ni-CD charge controller. The cell accepted charge within the expected voltage window and held load through a simulated mains-failure activation. BMS behaviour on the host fitting remained normal throughout.
• First installation cycle: Hold the test button for the full rated duration within 24 hours of fitting the new cell. This allows the charge controller to register the new cell's capacity baseline before the next scheduled compliance test. Skipping this step can cause the fitting to log a shorter-than-rated duration on its next inspection record.

Charge indicator staying red after new battery installation

Emergency lighting charge controllers expect to see cell voltage rise above a minimum threshold — typically around 3.3V — within a set time after installation. A cell that has been in storage may sit below that threshold until it receives its first charge. If the red fault indicator stays on after fitting, leave the fitting on mains power for 24 hours. If the indicator has not shifted to green by then, measure the cell terminal voltage directly — it should read above 3.6V at full charge.

Emergency light dimming partway through a duration test

A new Ni-CD cell straight from storage has not yet reached its full rated capacity. On the first test cycle, available charge may fall short of the full rated duration, causing the lamp to dim or cut before the test period ends. This is a one-cycle issue, not a faulty cell. Run the fitting on mains charge for a full 24-hour period after installation, then retest — cell voltage should hold above 3.0V under load through the complete test duration.