Sony MDR-HW700DS Replacement Battery 3.7V 800mAh LIS1494HNPPC

Sony MDR-HW700DS — 3.7V Li-Polymer Replacement Battery (LIS1494HNPPC)

This 3.7V, 800mAh Li-Polymer cell replaces the OEM LIS1494HNPPC battery in the Sony MDR-HW700DS wireless headset. It restores cordless operation when the original cell no longer holds enough charge to complete a listening or call session. Capacity matches the factory spec at 800mAh (2.96Wh).

• MDR-HW700DS platform fit: The HW700DS runs a single-cell Li-Polymer pack at 3.7V nominal to power both the audio processing and the wireless radio simultaneously. This cell matches that voltage rail and the original pack's flat 62.00 × 37.00 × 3.80mm form factor, so it seats correctly in the headset housing.
• Bench tested on actual hardware: We cycled this cell through charge and discharge on the MDR-HW700DS base station and confirmed the BMS handshake completes correctly — the charging indicator progresses as expected and the protection circuit trips at the correct voltage thresholds under combined radio and audio load.
• Base station conditioning on first use: Place the headset in the base station and let it complete one full uninterrupted charge cycle before use. The HW700DS base uses the charge cycle to log the new cell — until that first cycle finishes, the talk-time estimate displayed will be unreliable.

Voltage sag cutting the HW700DS out mid-call

The MDR-HW700DS draws from the battery on two loads at once — the audio decoder and the wireless radio. On a degraded or freshly installed cell that has not completed a conditioning cycle, the combined draw can pull cell voltage below the BMS cutoff threshold even when the charge indicator still shows partial capacity. This is a protection trip, not a dead battery. Run two to three full charge-discharge cycles through the base station and the cutoff threshold behaviour stabilises as the BMS calibrates to the new cell's actual voltage curve.

Base station shows charging error after battery replacement

If the base station displays a charging error or the LED flashes abnormally after fitting this cell, the BMS handshake has not completed. This happens when the cell voltage is below the base station's detection threshold — typically under 3.0V — after shipping. Remove the headset from the base, wait 30 seconds, then reseat it firmly and re-dock. If the error persists, connect the base station to power, reseat the headset, and leave it undisturbed for at least 15 minutes to allow the charging circuit to recognise the pack and begin the initial charge at trickle current.