AKG Balance K122IR Replacement Battery 2.4V 80mAh AP11A

AKG Balance K122IR / K216AFC Series — 2.4V Ni-MH Replacement Battery (AP11A)

This is a 2.4V, 80mAh Ni-MH replacement battery for AKG wireless headsets. It fits the Balance K122IR, Balance K216AFC, and Balance T216AFC. The cell restores wireless audio and microphone operation when the original pack no longer holds a charge.

• Balance K122IR, K216AFC, T216AFC compatibility: All three headsets share the same 2.4V cell format, connector pinout, and BMS handshake protocol. The AP11A, AP97, AP97A, and AP114 part numbers reference the same physical cell across production runs — the base station charges them identically.
• Bench tested on actual hardware: We cycled this cell through charge and discharge on the Balance platform. The BMS accepted the pack on first dock, initiated the charge cycle without error, and the headset registered a full charge state within the expected window.
• First-cycle base station protocol: Dock the headset immediately after fitting the new cell and leave it through one complete charge cycle before making a call. The base station needs to log the new cell's charge curve — until it does, the talk-time indicator will read inaccurately.

Base station not recognising new pack after install

The AKG Balance base station performs a handshake with the battery's BMS before it begins charging. If the cell arrives at storage voltage — typically around 1.0–1.1V per cell — the base may sit idle or flash an error rather than starting the charge cycle. This is not a faulty battery. Dock the headset, wait two minutes, then reseat it firmly. The base should detect the cell and begin the charge sequence; if voltage was very low, the first charge phase runs at reduced current until the cell reaches 2.0V.

Headset cutting out mid-call on a freshly charged battery

The Balance K122IR draws simultaneously from the audio amplifier and the DECT radio transmitter during a live call. Under that combined load, a Ni-MH cell in its first few cycles can sag below the headset's minimum operating voltage before the charge indicator suggests it should. This is a conditioning issue, not a cell defect — capacity improves over three to five full charge-discharge cycles. Run three complete cycles through the base station before judging talk time.