About this replacement
Motorola Xoom 2 10.1 Series — 3.7V Li-Polymer Replacement Battery (TB40 / SNN5896A)
This is a 3.7V, 6700mAh Li-Polymer replacement battery for the Motorola Xoom 2 10.1-inch Android tablet. It fits the MZ615, MZ616, and MZ617 variants. Capacity is 24.79Wh — matching the original TB40 specification.
- MZ615 / MZ616 / MZ617 platform fit: These three MZ-series tablets share the same battery bay dimensions, connector orientation, and charge IC handshake. One cell covers all three — no adapter or modification needed.
- Bench tested on actual hardware: We ran this cell through charge and discharge cycles on an MZ615 unit. The BMS accepted the charge IC handshake on the first cycle, voltage held stable across display-on and WiFi-active load states, and the protection circuit tripped correctly at the low-voltage cutoff threshold.
- Post-installation fuel gauge reset: After fitting this battery, run the tablet down to automatic shutoff — do not force-power it off — then charge uninterrupted to 100%. This gives the fuel gauge IC a full reference range against the new cell and clears the inaccurate percentage readings that appear immediately after a swap.
Xoom 2 shutting down at 15–25% battery remaining
This happens when the fuel gauge IC is still calibrated to an old, degraded cell whose voltage curve dropped steeply in that range. The new cell has a flatter discharge curve, but the IC doesn't know that yet. The tablet reads the voltage, maps it against its stored curve, and triggers a low-battery shutdown earlier than it should. One full discharge-to-shutoff followed by an uninterrupted charge to 100% recalibrates the IC against the actual voltage curve of the new cell. After that cycle, shutdowns at 15–25% stop.
Fast charging not available after battery swap
Some Xoom 2 units require one complete accepted charge cycle before the charge IC re-enables higher current delivery to a new cell. This is a protection behaviour — the controller runs an initial slow-rate cycle to profile the new cell before allowing full charge current. Use the original Motorola charger for the first charge, not a third-party adapter. After that first full cycle completes, fast charging resumes at the normal rate on subsequent charges.