T-Mobile Springboard HB3G1H Replacement Battery 3.7V 4000mAh

T-Mobile Springboard — 3.7V Li-Polymer Replacement Battery (HB3G1H)

This is a 3.7V, 4000mAh lithium-polymer replacement battery for the T-Mobile Springboard tablet. It uses OEM part number HB3G1H and fits directly into the Springboard's battery bay. If your Springboard won't hold a charge or powers off unexpectedly, this is the cell to replace.

• Springboard platform fit: The HB3G1H cell shares the same 3.7V nominal rail, physical footprint (125.70 × 69.20 × 3.90mm), and connector orientation as the original Springboard battery. The BMS handshake between the charge IC and this cell matches what the tablet's firmware expects during a charge cycle.
• Bench tested on actual hardware: We cycled this battery through charge and discharge on the Springboard platform. The charge IC accepted the cell without fault flags, and the BMS held cutoff voltage correctly at the low end of the discharge curve.
• Fuel gauge recalibration after swap: After installing this battery, run one full discharge to automatic shutoff, then charge uninterrupted to 100%. This resets the fuel gauge IC calibration against the new cell and resolves inaccurate percentage readings that commonly appear after a battery swap on this tablet.

Springboard shutting down at 15–25% remaining

The Springboard draws a combined load from the display backlight and Wi-Fi radio simultaneously. On a degraded or newly installed cell, this combined draw causes a voltage cliff — the pack voltage drops sharply under load even though the reported percentage looks reasonable. The fuel gauge IC reads a resting voltage, not a loaded voltage, so the shutdown catches users off guard. One full discharge-and-charge cycle lets the gauge recalibrate against the actual loaded curve of the new cell.

Fast charging not available after battery replacement

Some Springboard users report that fast charge stops working after a battery swap. The charge IC on this tablet completes a USB negotiation handshake during the first accepted charge cycle — if that cycle is interrupted, the IC may default to standard charge rates. Plug into the original Springboard charger and allow the first post-swap charge to complete fully without interruption. After that cycle finishes, fast charge availability typically restores to normal operation.