Asus A32-U5 11.1V Replacement Battery for U5F Notebook 4400mAh

Asus U5F / U5A / U5 Series — 11.1V Li-ion Replacement Battery (A32-U5)

This is an 11.1V 4400mAh (48.84Wh) lithium-ion battery for the Asus U5F, U5A, and U5 ultraportable notebooks. It replaces the original A32-U5 and cross-references A33-U5, along with Asus part numbers 90-NE62B2000, 90-NE61B2000, and related variants. If the original cell has degraded or no longer holds a usable charge, this unit slots in as a direct swap.

• U5F, U5A, and U5 compatibility: All three models run the same 11.1V three-cell architecture with an identical connector pinout and BMS handshake protocol. Asus used a shared battery platform across this ultraportable line, so one cell fits the full U5 range without modification.
• Bench tested on actual hardware: We ran this cell through charge and discharge cycles on U5-series hardware. The BMS communicated correctly with the BIOS, accepted a full charge without interruption, and reported capacity within expected tolerance of the rated 4400mAh.
• Post-install calibration on the U5: After fitting this battery, run one full discharge until the laptop hibernates on its own, then charge uninterrupted to 100% without using the machine. This resets the BIOS battery learn cycle and clears the inaccurate health warning that typically appears after a cell swap on U5-series notebooks.

BIOS reporting poor battery health immediately after fitting the A32-U5

The U5 BIOS reads health data from the battery's EEPROM, which stores cycle count and charge history from the previous cell. When a new battery is installed, the EEPROM data doesn't match what the BIOS expects from a fresh cell, so it flags a health warning. This is a data mismatch, not a fault with the replacement unit. Running one full discharge-to-hibernate cycle followed by an uninterrupted charge to 100% lets the fuel gauge IC recalibrate against the new cell and updates the EEPROM baseline. After one or two complete cycles, the health indicator should normalise.

U5 shuts down unexpectedly at 20–30% charge shown on screen

This happens when the cell voltage drops sharply under combined CPU and display load — a voltage cliff the fuel gauge IC didn't predict from earlier shallow cycles. The on-screen percentage reads 20–30%, but the actual cell voltage has already fallen below the BMS cutoff threshold. The fuel gauge hasn't yet mapped the new cell's discharge curve accurately. Fix this by completing two or three full discharge-to-hibernate cycles; after calibration, the gauge tracks voltage correctly and the premature shutdown stops occurring.