Sony SRS-XB10 Replacement Battery 3.7V 1400mAh SF-08

Sony SRS-XB10 / SRS-XB12 / WH-L600 — 3.7V Li-Polymer Replacement Battery (SF-08 / 1-853-641-13)

This is a 3.7V, 1400mAh Li-Polymer cell for the Sony SRS-XB10, SRS-XB12, and WH-L600. It replaces an original pack that no longer holds charge or has swollen beyond safe use. Slot dimensions are 42.10 × 34.90 × 9.00mm — confirm against your existing cell before ordering.

• SRS-XB10, SRS-XB12, and WH-L600 fitment: All three units share the same 3.7V cell footprint and connector pinout. The BMS on each device reads the same voltage curve, so the pack transitions between charge and discharge states without firmware flags or error codes.
• Bench tested on actual hardware: We cycled this pack through full charge and discharge on a WH-L600 base station. The BMS completed handshake on the first charge cycle and accepted the cell without triggering a fault indicator.
• First-use charge protocol for WH-L600: Seat the headset in the base station and let it run a full uninterrupted charge before taking a call. The WH-L600 logs the new cell during that first cycle — skipping it causes the talk-time indicator to display inaccurate readings for several sessions.

Base station showing charging error after fitting a new pack

A fresh Li-Polymer cell ships at storage voltage — typically 3.6–3.7V. The WH-L600 base station checks cell voltage at contact before initiating the charge sequence. If the pack sits at the low end of storage voltage, the base may flag an error rather than begin charging. Remove the headset, reseat it firmly, and leave it undisturbed for 10–15 minutes. If the error clears, the BMS has accepted the cell and charging is underway — target a full cycle to 4.2V before first use.

SRS-XB10 cutting out during playback on a charged battery

The SRS-XB10 draws a combined load from the Bluetooth radio and the amplifier simultaneously during bass-heavy playback. If the cell voltage sags below the BMS cutoff threshold under that combined draw, the unit shuts off even when the charge indicator shows a partial or full state. This is more common in the first few cycles on a new cell before the pack reaches full capacity. Run three to five full charge-discharge cycles — cutoff events typically stop once the cell stabilises above 3.75V under load.