About this replacement
Atmos Suctions Pump A161 / A261 / C161 / C261 — 7.4V Li-ion Replacement Battery (110607-O)
This is a 7.4V Li-ion replacement battery rated at 6700mAh (49.58Wh) for the Atmos Suctions Pump A161, A261, C161, and C261. These portable medical suction pumps are used for airway clearance and secretion removal in clinical and home care settings. The OEM part numbers are 110607-O and 313.0053.0.
- A161 / A261 / C161 / C261 platform: All four models share the same 7.4V battery bay, connector pinout, and BMS communication protocol. One cell fits across the range because the charge IC and voltage rails are identical on the underlying pump platform.
- Bench tested on actual hardware: We ran this cell through charge, discharge, and the pump's BMS handshake sequence. The BMS accepted the cell, completed its initialisation, and the charge indicator tracked normally through a full cycle.
- Post-installation self-test cycle: After fitting the battery, allow the pump to complete its full power-on self-test without interruption. The device runs a BMS verification routine at startup — cutting power mid-sequence triggers a false battery fault that persists until the next clean reboot.
Medical device alarming low battery immediately after a confirmed full charge
The Atmos pump's BMS compares the incoming cell against a stored OEM chemistry baseline. A new cell that hasn't completed its first full charge-discharge cycle can present a capacity signature that sits below that threshold, triggering a low-battery alarm even when the cell is fully charged. This isn't a fault with the cell — it's the BMS learning routine waiting for calibration data. Run one complete charge cycle to zero and back to full before relying on the alarm indicator for clinical use. After that cycle, the alarm threshold maps correctly to actual charge state.
Pump will not power on after the replacement cell sat in storage
Li-ion cells self-discharge during storage. If the cell voltage drops below approximately 2.5V per cell (5.0V at the pack level), the Atmos BMS will refuse to initiate power-on as a protection measure. Place the battery in the pump and connect to mains charge immediately — the charge IC will apply a low-current pre-charge to recover the cell voltage before resuming normal charge rate. If the charge indicator does not respond within 30 minutes at this stage, the cell has discharged below recovery threshold and the pack should be replaced.