About this replacement
Bose SoundLink Color II / SoundLink 535 Series — 3.7V Li-ion Replacement Battery (064454)
This 3.7V, 2600mAh Li-ion cell replaces the OEM battery in the Bose SoundLink Color II (V35) and SoundLink 535 series portable Bluetooth speakers. It fits the V35, 535, 525II, and 535II models using OEM part numbers 064454 and 626161-0010. When the original cell degrades and the speaker stops holding a charge, this replacement restores full wireless portability.
- V35 and 535-series compatibility: These models share the same battery bay dimensions, connector pinout, and BMS communication protocol. The 066.10 × 21.74 × 18.60mm cell fits without modification, and the BMS handshake passes charge-state data to the speaker's onboard fuel gauge correctly.
- Bench tested on actual hardware: We cycled this cell through charge and discharge on the V35 platform. The BMS accepted charge from the speaker's USB input without triggering over-current cutoff, and fuel gauge readout tracked accurately from full to low-battery warning.
- Monthly full-discharge on the V35: The SoundLink Color II is typically kept on a desk and topped off constantly. Discharge the speaker fully — below the low-battery LED alert — at least once a month. Without occasional full cycles, the fuel gauge drifts and the speaker shuts down well before the cell is actually empty.
Audio distorting before the battery indicator reaches empty
As the Li-ion cell discharges below roughly 3.5V, the amplifier inside the SoundLink Color II starts drawing more current to maintain volume — and a degraded or partially discharged cell cannot sustain that current without voltage sag. The sag clips the amplifier's supply rail before the battery indicator hits the final LED. The speaker sounds distorted or compressed even though the indicator shows charge remaining. Replacing the cell with a fresh 2600mAh unit restores the voltage headroom the amplifier needs at high output.
Speaker won't wake from USB after sitting unused for weeks
A Li-ion cell left discharged for an extended period drops below the minimum acceptance voltage for USB charging — typically under 2.5V. When that happens, the speaker's charge circuit does not respond to USB connection and the unit appears completely dead. Most SoundLink models require the cell to be above ~2.9V before the charging IC will initiate. To recover, hold the power button for 10 seconds while connected to USB — this forces a low-current pre-charge trickle that can bring the cell back up to the acceptance threshold.