Dell XPS 12 9250 Replacement Battery 7.6V 3900mAh 9TV5X

Dell XPS 12 9250 / Latitude 12 7275 — 7.6V Li-Polymer Replacement Battery (9TV5X)

This 7.6V 3900mAh (29.64Wh) Li-Polymer battery replaces the original cell in the Dell XPS 12 9250 and Latitude 12 7275 convertible ultrabooks. It cross-references OEM part numbers 9TV5X, 7VKV9, V55D0, and T02H. If your original battery no longer holds charge or the system shuts down unpredictably under load, this is the direct replacement.

• XPS 12 9250 and Latitude 12 7275 compatibility: Both platforms share the same 7.6V two-cell Li-Polymer architecture, flat-profile connector, and BMS communication protocol — which is why a single cell fits both the XPS 12 convertible and the Latitude 12 7275 detachable.
• Bench tested on actual hardware: We cycled this cell on an XPS 12 9250 chassis and confirmed the BMS handshake completes correctly — the system exits the "plugged-in, not charging" state and the fuel gauge IC begins tracking state-of-charge within the first full cycle.
• Post-install calibration on the XPS 12: After fitting this cell, run one full discharge to hibernate-cutoff, then charge uninterrupted to 100%. This forces the BIOS battery learn cycle to reset against the new cell and clears the inaccurate health warning that appears after every cell swap on this platform.

BIOS reporting battery health as poor immediately after replacement

The XPS 12 9250 stores battery health data in EEPROM on the old cell. When you swap to a new cell, the BIOS reads the cycle count and charge history it expects to find — and gets a blank slate instead. Dell's firmware interprets this as a degraded or unknown battery and flags health as "poor" in the BIOS and in Dell Power Manager. This is not a fault with the replacement cell. Run one full discharge-to-hibernate cycle followed by a full uninterrupted charge to 100%, and the learn cycle will overwrite the stale EEPROM values with accurate data from the new cell.

Laptop shutting down at 20–30% shown on the fuel gauge

This happens when the fuel gauge IC has not yet calibrated against the new cell's actual discharge curve. In the first few cycles after a swap, the IC maps state-of-charge using the old cell's parameters — so 20% displayed can correspond to a voltage that actually triggers the BMS low-voltage cutoff. The fix is not a hardware issue. Complete two to three full discharge-and-charge cycles without interruption. After that, the fuel gauge recalibrates and reported percentage aligns with real cell voltage — the shutdown-at-20% behaviour stops.