About this replacement
Sony MDR-DS7500 — 3.7V Li-Polymer Replacement Battery (LIS1410)
This 3.7V, 1200mAh Li-Polymer cell replaces the original LIS1410 battery in the Sony MDR-DS7500 wireless headset. The MDR-DS7500 is a closed-ear home audio headset that streams audio wirelessly from a base station. When the original cell degrades and the headset stops holding charge, this replacement restores full wireless operation.
- MDR-DS7500 fit: The LIS1410 is the sole cell format used in this headset. The slim 51.40 x 34.50 x 6.00mm Li-Polymer pouch matches the housing geometry and connects directly to the headset's internal BMS. No adapter or modification needed.
- Bench tested on actual hardware: We cycled this cell through the MDR-DS7500's charge circuit. The BMS accepted the new pack, completed a full charge sequence without error flags, and held a stable 3.7V nominal rail under combined audio and RF transmitter draw.
- First-use cycle on the MDR-DS7500: Place the headset in the base station and let it complete one full uninterrupted charge before use. The base station logs the new cell during that first cycle — until it does, the talk-time indicator will read inaccurately.
Why the MDR-DS7500 cuts out mid-listen on a new battery
The MDR-DS7500 draws current from two loads simultaneously — the audio amplifier and the DECT radio transmitter. Under that combined draw, a cell that arrived at storage voltage (around 3.6V) can sag below the BMS cutoff threshold momentarily, triggering a shutdown. This is not a faulty battery. Place the headset back on the base, allow it to charge fully to 4.2V, and the cutouts stop after the first complete cycle normalises the cell's internal resistance.
Base station shows full charge but headset dies quickly after first use
Replacement cells ship at partial storage voltage — typically 3.6–3.7V — not a full 4.2V charge. The base station's charge indicator can read "full" prematurely if the handshake completes before the cell reaches true capacity. The fix is straightforward: leave the headset docked for a complete charge cycle of several hours without interruption. After that first full cycle, charge time and talk time will both normalise.