About this replacement
JBL Live 760NC / Tune 760NC — 3.8V Li-Polymer Replacement Battery (HPT693331)
This 3.8V, 500mAh Li-Polymer cell replaces the internal battery in the JBL Live 760NC and Tune 760NC wireless over-ear headphones. It restores power to Bluetooth audio, active noise cancellation, and onboard controls when the original cell has degraded or failed. Dimensions are 32.30 × 33.00 × 6.70mm — verify against the existing cell before fitting.
- Live 760NC and Tune 760NC compatibility: Both models share the same internal chassis layout, connector pinout, and BMS handshake protocol, which is why a single cell covers both. Voltage tolerance across the two platforms is identical at 3.8V nominal.
- Bench tested on actual hardware: We cycled this cell through charge and discharge on a Live 760NC unit and confirmed BMS handshake completion, stable cutoff at low voltage threshold, and no thermal anomaly under sustained ANC-plus-Bluetooth draw.
- First-charge protocol for ANC headphones: After fitting, run the headset through one full charge-to-discharge cycle with ANC active. The noise-cancellation DSP draws a separate power rail — a partial cycle leaves that rail calibration incomplete, which causes the battery indicator to read inaccurately until a full cycle is logged.
Why the Live 760NC cuts out mid-call on a degraded cell
The Live 760NC runs Bluetooth audio, ANC processing, and the microphone circuit simultaneously during calls. Combined draw spikes briefly when the ANC chip adjusts to ambient noise changes. A degraded or partially charged cell cannot sustain that spike without voltage dropping below the BMS cutoff threshold, which triggers an immediate shutdown. A fresh cell at full charge holds the voltage rail stable through those transient peaks.
Battery indicator stuck at full after replacement but headset shuts off early
A replacement cell shipped at storage voltage — typically around 3.6–3.7V — sits close enough to nominal that the headset firmware reads it as full. The fuel gauge does not recalibrate until a complete charge-discharge cycle is completed. Until that cycle runs, the indicator stays high and then drops sharply before the actual low-voltage cutoff kicks in. Charge the headset fully, use it until it powers off on its own, then charge again — the indicator will track accurately from that point.