About this replacement
Dell Studio 1535 / 1555 Series — 11.1V Li-ion Replacement Battery (312-0701)
This 11.1V Li-ion battery replaces the original cells in the Dell Studio 1535, 1536, 1537, and 1555 laptops. Capacity is 6600mAh (73.26Wh), matching the stock specification. It uses OEM-compatible part numbers including 312-0701, KM958, MT264, and WU946, among others.
- Studio 1535 / 1536 / 1537 / 1555 compatibility: These four models share the same battery bay dimensions, 11.1V nominal rail, and connector pinout. The BMS handshake protocol is identical across the series, so one cell works across all four without modification.
- Bench tested on actual hardware: We ran this cell through charge and discharge cycles on a Studio 1555. The BMS negotiated correctly with the Dell EC, charge current stepped down at the expected threshold, and the protection circuit tripped cleanly at low-voltage cutoff with no false disconnects during load transitions.
- Post-install BIOS learn cycle: After fitting this battery, run the laptop down to hibernate cutoff on battery power, then charge uninterrupted to 100% without using the machine. 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 Studio-series hardware.
Why the Studio 1535 shuts down at 20–30% remaining after a battery swap
The Dell EC relies on EEPROM data from the previous cell to map the discharge curve. When a new cell goes in, the stored curve no longer matches actual chemistry, so the EC calls a low-voltage shutdown well before the cell is genuinely empty. The fuel gauge IC needs two to three full discharge-to-charge cycles to recalibrate against the new cell's actual voltage slope. Until that calibration completes, the percentage readout is unreliable and the EC will cut power early. Run the full discharge-then-charge sequence three consecutive times and the shutdown behaviour corrects itself.
BIOS reporting battery health as "poor" or "replace soon" immediately after install
This warning comes from the EEPROM data written by the old cell, not from any fault in the new one. The Dell BIOS reads cycle count and health flags stored on the battery's embedded controller, and a new cell ships with values the BIOS interprets as degraded until a learn cycle runs. Perform one full discharge to hibernate followed by an uninterrupted charge to 100%, then reboot and enter the BIOS battery diagnostics. The health flag clears once the learn cycle registers a complete charge event against the new cell's rated capacity.