Garmin Venu SQ Music Replacement Battery 3.87V 200mAh

Garmin Venu SQ Music / Venu SQ2 Music — 3.87V Li-Polymer Replacement Battery (361-00136-10)

This is a 3.87V, 200mAh Li-Polymer cell for the Garmin Venu SQ Music and Venu SQ2 Music smartwatches. It matches OEM part numbers 361-00136-10, 361-00136-20, and 361-00136-21. The cell measures 27.30 × 20.40 × 3.30mm — physical fit matters in this chassis, so confirm dimensions before ordering.

• Venu SQ Music and SQ2 Music compatibility: Both models share the same battery bay geometry, connector pinout, and BMS handshake protocol. The fuel gauge IC on each platform reads cell impedance at first charge — the same cell works across both without modification.
• Bench tested on actual hardware: We ran this cell through charge and discharge cycles on the Venu SQ platform. The BMS accepted the cell without fault flags, the fuel gauge calibrated on the first full charge cycle, and the connector seated without forced fit.
• Post-swap charging protocol: After fitting this cell, place the watch on its magnetic charger immediately and charge to 100% before use. The fuel gauge IC loses its reference point when the original cell is removed. Without a full charge cycle from near-zero, the percentage readout will be inaccurate and the watch may shut off unexpectedly at reported mid-charge levels.

Why always-on display and continuous HR monitoring hit a 200mAh cell harder than expected

The Venu SQ Music runs a transflective display that draws current constantly when always-on mode is active. Pair that with the optical HR sensor polling every second and the result is a sustained combined draw that a 200mAh cell feels quickly. Garmin's power management firmware offsets this by throttling GPS and music playback sampling rates when the cell drops below 20%. If daily charge life feels shorter than expected in the first week, disable always-on display and check whether continuous HR tracking is set — those two settings account for the largest share of draw on this platform.

Watch not pairing to phone after battery replacement

Removing the battery clears the active BLE session between the watch and the Garmin Connect app. The watch does not automatically re-establish that session on power-up — it waits for an explicit pairing request. On the watch, go to Settings → Phone → Pair Phone, then open Garmin Connect on your phone, navigate to the device settings, and select Pair a New Device. Complete the pairing before syncing any data. Once paired, the connection is stable and no further action is needed.