About this replacement
Dell Latitude X1 — 11.1V Li-ion Replacement Battery (312-0341)
This is an 11.1V, 2200mAh (24.42Wh) Li-ion battery for the Dell Latitude X1 ultraportable notebook. It replaces OEM part numbers 312-0341, Y6457, T6840, U6256, 312-0342, and X6753. If the original cell no longer holds a charge or the system won't run unplugged, this is the direct swap.
- Latitude X1 fitment: All six OEM part numbers above cross-reference to the same battery bay, connector pinout, and BMS handshake on the Latitude X1 motherboard. Dell used multiple supplier codes across production runs — the electrical spec is identical across all variants.
- Bench tested on actual hardware: We ran this cell through full charge and load cycles on a Latitude X1 unit. The BMS communicated correctly with the system, charge accepted without error, and the fuel gauge IC registered current and voltage within expected range.
- BIOS learn cycle after install: After fitting this battery, run the laptop down to hibernate-cutoff under normal use, then charge uninterrupted to 100%. This resets the BIOS battery learn cycle and clears the inaccurate health warning the system throws after any cell swap.
Why the Latitude X1 shuts down at 20–30% after a battery swap
The Latitude X1 BIOS stores discharge curve data from the previous cell. When a new cell is installed, that stored curve no longer matches actual voltage behaviour. At around 20–30% shown, the new cell hits a voltage cliff under combined CPU and display load that the old calibration data doesn't anticipate. The BIOS cuts power before the fuel gauge reaches zero because the voltage drop looks like a fault. Run two full discharge-to-hibernate then full-charge cycles and the BIOS recalibrates against the new cell's actual curve.
BIOS reporting 0% or "unknown" battery immediately after fitting
The fuel gauge IC on the Latitude X1 reads EEPROM data embedded in the battery pack to identify cell capacity and state of charge. A freshly installed cell presents EEPROM values the IC hasn't seen before, so it defaults to 0% or flags the battery as unknown. This is not a fault with the battery or the laptop. Boot into Windows, confirm AC adapter is connected, then let the battery charge to 100% uninterrupted — the IC will initialise against the new EEPROM data. After one full discharge-recharge cycle, the gauge should read accurately. Target 11.1V at full charge as your confirmation point.