About this replacement
Dell Studio XPS 13 / Studio XPS 1340 — 11.1V Li-ion Replacement Battery (312-0773)
This 11.1V, 4400mAh (48.84Wh) Li-ion battery replaces the original pack in the Dell Studio XPS 13 and Studio XPS 1340. It fits the same bay and connects to the same three-wire BMS circuit as the factory cell. OEM part numbers covered include 312-0773, 312-0774, P866C, P891C, T555C, T561C, P878C, PP17S, R437C, and W004C.
- Studio XPS 13 and 1340 platform fit: Both models share the same 11.1V three-cell battery bay, connector pinout, and BMS handshake protocol — that is why a single replacement cell covers both. The thermistor line and ID resistor values match across all listed OEM part numbers.
- Bench tested on actual hardware: We ran this cell through a full charge and discharge cycle on a Studio XPS 1340. The BMS accepted the charge handshake immediately, reported correct voltage across all three cells, and the thermal cutoff did not trip at any point during the test.
- Post-install calibration on the Studio XPS: After fitting, run the battery down until the laptop hibernates, then charge uninterrupted to 100% without interruption. This forces the Dell BIOS battery learn cycle to reset against the new cell and clears the inaccurate health warning that appears after every cell swap.
BIOS reporting poor battery health immediately after replacement
Dell's BIOS stores cycle count, charge history, and health data in EEPROM on the original battery pack. When a new cell arrives, that EEPROM data is blank or mismatched, so the BIOS flags the battery as degraded before it has ever been charged. This is a firmware read problem, not a cell fault. One full discharge-to-hibernate followed by an uninterrupted charge to 100% completes the learn cycle and overwrites the stale health flag. After that cycle, the BIOS should report the battery as normal.
Laptop shuts down unexpectedly at 20–30% charge shown
The fuel gauge IC in the Studio XPS calibrates its remaining-capacity estimate against the old cell's voltage curve. A new cell with a slightly different voltage-to-capacity curve hits a steep voltage cliff at a point the IC still reads as 20–30%. Under full CPU and display load, voltage drops fast enough to trigger the low-voltage cutoff before the gauge reaches 0%. Run two or three full discharge-to-hibernate and full-charge cycles to let the fuel gauge IC remap its estimate against the new cell's actual curve. After calibration, shutdowns at high displayed percentages stop.