Dell Inspiron 1564 Replacement Battery 11.1V 4400mAh

Dell Inspiron 1564 Series — 11.1V Li-ion Replacement Battery (312-1021)

This 11.1V, 4400mAh (48.84Wh) Li-ion battery replaces the original pack in the Dell Inspiron 1564, 1564D, and 1564R laptops. It fits the standard P07E and P08F001 board platforms and uses OEM-matched connector pinout and BMS communication protocol. Install it when the original cell no longer holds a usable charge under load.

• Inspiron 1564 platform fit: The 1564, 1564D, and 1564R all run the same P07E battery bus with identical connector housings and BMS handshake. Any cell carrying part number 312-1021 or cross-references like NKDWV, JKVC5, or FH4HR communicates correctly with the Dell EC firmware on these boards.
• Bench tested on actual hardware: We ran this cell on a 1564 board under combined CPU and display load. The BMS held voltage above the 9.8V cutoff threshold through full discharge cycles and reported state-of-charge accurately to the EC within two calibration passes.
• First-cycle conditioning on Dell laptops: After installing, run one full discharge down to hibernate cutoff, then charge uninterrupted to 100%. This resets the BIOS battery learn cycle and clears the inaccurate health warning the Dell EC flags after every cell swap.

BIOS reporting battery health as poor immediately after swap

Dell's embedded controller reads health data from the battery EEPROM and compares it against the previous cell's stored cycle count and charge history. A fresh cell has a blank or factory-default EEPROM, so the EC flags it as degraded before any learn cycle runs. This is not a fault with the replacement cell. Run one full discharge-to-hibernate then an uninterrupted charge to 100% — after that cycle the EC recalibrates and the health warning clears.

Laptop shutting down at 20–30% charge shown on screen

This happens when the fuel gauge IC hasn't yet mapped the new cell's actual voltage curve. The old curve still sits in the EC's memory, so the reported percentage drifts from the real state-of-charge. Under full CPU plus display load, the cell hits its low-voltage cliff while the screen still shows 20–30%. Two complete discharge-and-charge calibration cycles reset the fuel gauge IC against the new cell chemistry. After calibration, shutdown should not occur above 5% reported charge.