Samson AirLine 88 Replacement Battery 3.7V 230mAh

Samson AirLine 88 / AirLine 99M — 3.7V Li-Polymer Replacement Battery (1-OTH0138)

This 3.7V, 230mAh lithium-polymer cell replaces the original battery in the Samson AirLine 88, AirLine 99M, and SWAH2 AirLine Micro bodypack transmitters. The pack measures 32.10 × 16.80 × 4.70mm — physically identical to the OEM cell. Voltage and capacity match OEM spec exactly.

• AirLine 88, AirLine 99M, and SWAH2 AirLine Micro compatibility: All three bodypacks share the same transmitter circuit board, connector pinout, and BMS handshake protocol — one cell SKU covers the full range without modification.
• Bench tested on actual hardware: We ran this cell in an AirLine 88 bodypack and confirmed the BMS completed its handshake on the first insertion. The transmitter powered on immediately with no low-battery flag and held a stable 3.7V output rail across the RF and audio draw cycle.
• First charge in the transmitter — not standalone: On first use, seat the battery in the bodypack and charge it via the AirLine charging dock for a complete cycle before going live. The transmitter's BMS logs the new cell during this cycle and begins calibrating the battery indicator — skipping it leaves the gauge inaccurate for the first several uses.

Why the AirLine 88 bodypack cuts out mid-transmission on a new battery

A fresh Li-polymer cell shipped at storage voltage — typically around 3.6–3.65V — has not yet gone through a conditioning cycle. Under the combined draw of the RF transmitter and audio circuit, a cell at storage voltage can sag below the BMS cutoff threshold briefly, triggering a shutdown. This is not a fault in the battery or the bodypack. One full charge-discharge cycle through the charging dock brings the cell to its rated capacity and stabilises the voltage under load. After that first cycle, mid-transmission cutouts caused by voltage sag stop.

Talk time noticeably shorter than rated for the first few uses

Li-polymer cells do not deliver full rated capacity on cycle one — 230mAh is the stable capacity reached after three to five full charge-discharge cycles. Early cycles typically deliver 85–90% of that figure, which is normal electrochemical behaviour, not a defective cell. Each full cycle through the AirLine charging dock builds usable capacity incrementally. By cycle five, runtime should stabilise at the rated level — if it does not, check that the dock contacts are clean and the bodypack is seating fully before writing off the cell.