About this replacement
Ticwatch Pro 3 — 3.85V Li-Polymer Replacement Battery (SP492929SI)
This is a 3.85V, 570mAh lithium-polymer cell for the Ticwatch Pro 3 smartwatch. It replaces the original SP492929SI battery when the watch can no longer hold charge through a full day. Fits the Pro 3 only — confirm your model before ordering.
- Pro 3 platform fit: The Pro 3 runs a dual-display stack — an OLED layer plus an FSTN always-on layer — both drawing from the same 3.85V rail. This cell matches the original connector, PCM pinout, and physical footprint (28.90 × 25.90 × 5.00mm) that the chassis accepts.
- Bench tested on actual hardware: We ran the SP492929SI replacement through charge and discharge cycles on the Pro 3 platform. The onboard BMS accepted the cell without fault codes, and the fuel gauge IC tracked state-of-charge correctly after a full conditioning cycle.
- Post-swap charging on the Pro 3: After fitting this cell, place the watch immediately on its magnetic charger and run it to 100% before first use. The fuel gauge IC on the Pro 3 loses its charge reference during a cell swap and cannot recalibrate without a full charge cycle from near-zero — skipping this causes the percentage to read incorrectly for days.
Why the Pro 3 dual-display draws harder than single-screen watches
The Pro 3 uses Mobvoi's dual-processor architecture — a Snapdragon Wear 4100 for the full OLED mode and an embedded low-power co-processor for the FSTN essential mode. When both layers are active during workouts or navigation, current draw jumps sharply compared to FSTN-only standby. A new cell at full 570mAh capacity handles those peaks cleanly. A degraded original cell at 60–70% usable capacity cannot sustain the voltage under that combined load, which triggers an early low-battery shutdown well before 0% is displayed.
Watch not pairing with phone after battery replacement
Removing the battery cuts power to the BLE radio completely, which closes any active Bluetooth session without a clean disconnect. The phone retains the old pairing entry, but the watch boots fresh with no matching session ID. The two devices fail to reconnect automatically because the bond keys no longer align. Fix this by removing the Ticwatch from your phone's Bluetooth device list entirely, then re-pairing through the Mobvoi app from scratch.