Bose V35 SoundLink Replacement Battery 3.7V 3400mAh

Bose SoundLink Color II / Mini II — 3.7V Li-ion Replacement Battery (064454)

This 3.7V 3400mAh Li-ion cell replaces the original battery in Bose SoundLink Color II and SoundLink Mini II portable Bluetooth speakers. It also fits models listed under part numbers 626161-0010 and 064455. Capacity is sourced from the cell spec — 3400mAh (12.58Wh).

• SoundLink Color II and Mini II compatibility: Both models share the same 3.7V single-cell architecture, connector pinout, and BMS handshake protocol. One battery covers both platforms because the charge controller logic is identical across this speaker generation.
• Bench tested on actual hardware: We cycled this cell through the SoundLink Color II charge controller at full volume load. The BMS held charge cutoff cleanly at 4.2V and triggered low-voltage protection at the correct threshold without tripping a false shutdown during amplifier draw spikes.
• Monthly discharge cycle for desk-top users: If this speaker sits on a desk and gets topped off before it drops below 50%, run it down past 20% at least once a month before recharging. Constant partial charging without a full discharge causes fuel gauge drift on the onboard controller, making the battery indicator read inaccurately within a few months.

Bluetooth dropping at high volume on a new battery

At peak volume, the amplifier and Bluetooth radio draw current simultaneously. If the cell's internal resistance is elevated — even on a new but poorly manufactured cell — voltage sags under that combined load. The speaker's protection circuit interprets the sag as a near-empty cell and throttles output or cuts the radio link. Check that the replacement cell holds above 3.6V under load; a healthy 3400mAh cell should not sag below that threshold during normal playback.

Audio distorting before the battery indicator reaches empty

This happens when the cell's actual voltage drops faster than the fuel gauge expects — the amplifier hits its minimum operating voltage and clips the signal before the indicator warns you. It is common after a degraded cell is replaced with one that has been stored discharged for too long, leaving the cell in a partially recovered state. Charge the new battery to 100% before first use and let it complete a full cycle. If distortion persists below the half-charge mark, verify cell voltage directly — it should read at least 3.7V at rest when the indicator shows two bars.