About this replacement
Dell XPS M1330 / Inspiron 1318 — 11.1V Li-ion Replacement Battery (312-0739)
This 11.1V, 6600mAh Li-ion battery replaces the original pack in the Dell XPS M1330, XPS M1350, and Inspiron 1318. It matches the original cell count, voltage rail, and connector pinout. OEM part numbers covered include 312-0739, PU563, 451-10473, TT485, PU556, WR050, 312-0566, and 312-0567.
- XPS M1330, M1350, and Inspiron 1318 compatibility: These three models share the same 11.1V three-cell series architecture, identical connector housing, and the same BMS communication protocol over the SMBus line — which is why one cell pack covers all three.
- Bench tested on actual hardware: We cycled this battery through full charge and discharge on an XPS M1330 unit. The BMS handshake completed correctly, BIOS recognised the pack, and the SMBus data lines reported capacity without error flags.
- First-cycle recalibration on Dell XPS: After installation, run the laptop down to hibernate cutoff on battery only — no AC adapter — then charge uninterrupted to 100%. This resets the BIOS battery learn cycle and clears the inaccurate health warning that appears after every cell swap on these Dell models.
BIOS reporting poor battery health immediately after swap
Dell's BIOS reads health data from the battery's EEPROM — a small memory chip that stores cycle count, rated capacity, and charge history. When a new cell goes in, that EEPROM data does not match the BIOS's learned profile for the old pack, so the system flags it as degraded. This is not a fault with the new battery. Run one full discharge-to-hibernate cycle followed by a full uninterrupted charge, and the BIOS will rewrite its reference data against the new cell's actual readings.
Laptop shuts down abruptly when the gauge reads 20–30%
This happens when the cell cannot hold voltage under combined CPU and display load at low state of charge. The fuel gauge IC estimates remaining capacity based on voltage curves, but aged or freshly installed cells hit a voltage cliff earlier than the curve predicts — so the system cuts power before the gauge reaches zero. The fix is calibration: discharge fully to hibernate, then charge to 100% without interruption. After two to three full cycles, the fuel gauge IC recalculates the voltage-to-capacity curve and the shutdowns stop. If it persists past three cycles, check that the AC adapter is delivering a stable 19.5V under load.