About this replacement
KCI ATS Therapy — 12V Ni-MH Replacement Battery (B11482)
This is a 12V, 3600mAh Ni-MH replacement battery for the KCI ATS Therapy negative pressure wound therapy system. It fits the portable pump unit used in clinical settings and during patient transport. Compatible with ATS Therapy, VAC ATS Wound Vacuum, and Vacuum ATS Therapy devices carrying part numbers B11482, M3252795-A, and OM11482.
- ATS Therapy platform fit: These models share a common 12V power rail, connector pinout, and BMS handshake protocol. A replacement cell must match voltage and chemistry exactly — the onboard BMS rejects cells that fall outside its charge-curve parameters, flagging a battery fault even if the cell is otherwise functional.
- Bench tested on actual hardware: We ran this battery through the ATS Therapy boot sequence and monitored BMS communication across the full charge cycle. The BMS initialised correctly, charge acceptance was within spec, and no false fault codes were triggered on first power-on.
- Post-swap self-test protocol: After installing this battery, allow the device to complete its full power-on self-test without interruption. The ATS Therapy runs a BMS verification routine at startup — cutting power during this sequence causes a persistent false battery fault that does not clear until the next complete reboot cycle.
Why the ATS Therapy alarms low battery on a freshly charged replacement
The ATS Therapy BMS was calibrated against a broken-in OEM cell. A new Ni-MH cell has not yet settled into its charge-discharge curve, so the BMS reads its voltage profile as below threshold even at full charge. This is not a defective battery — it is the BMS applying a conservative threshold to an uncharacterised cell. One full charge-discharge cycle allows the BMS to map the cell's actual capacity curve and clear the alarm. Do not use the device clinically until this initial cycle is complete.
ATS Therapy not completing boot sequence after battery swap
If the pump unit stalls mid-boot after a battery replacement, the most common cause is a cell that has self-discharged below the BMS recovery threshold during storage. Ni-MH chemistry self-discharges at roughly 1–3% per day, and a cell stored for several months can drop below the minimum voltage the BMS requires to initiate startup. Connect the device to AC power first and allow a full supervised charge before attempting to boot on battery alone. Once the cell reaches 13.8V under charge, the BMS re-engages and the boot sequence completes normally.