About this replacement
Asus R1 / R1F / R1E Tablet PC — 11.1V Li-ion Replacement Battery (A32-R1)
This is an 11.1V, 4400mAh (48.84Wh) lithium-ion battery for the Asus R1, R1F, and R1E Tablet PC. It replaces OEM part numbers A32-R1, 90-NGA1B3000, and 70-NGA1B1001M. If the original cell is failing to hold charge or triggering low-battery shutdowns, this is the direct replacement.
- R1 series compatibility: The R1, R1F, and R1E all share the same battery bay dimensions, connector pinout, and BMS communication protocol — the BIOS handshake is identical across this platform, so one cell covers the full lineup.
- Bench tested on actual hardware: We ran charge and discharge cycles on the R1 platform and confirmed the BMS negotiates correctly at all three pins — the cell reports voltage, temperature, and state-of-charge without triggering an unknown battery error.
- Post-install calibration on the R1: After fitting this cell, run one full discharge to hibernate-cutoff, 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 this platform.
Why the R1 reports poor battery health immediately after a cell swap
The Asus R1 BIOS reads health data from EEPROM registers that were written by the original factory cell during its lifetime. A new cell arrives with fresh EEPROM values that don't match the usage history the BIOS expects. Until the system runs a full learn cycle, it flags the battery as degraded or unknown — even though the cell is new. One complete discharge-to-hibernate followed by an uninterrupted full charge rewrites the learn-cycle registers and clears the warning.
R1 shutting down at 20–30% charge shown on the gauge
This is a voltage-cliff issue, not a gauge error. Under combined CPU and display load the cell voltage drops faster than the fuel gauge IC can track, and the BIOS triggers an emergency shutdown before the displayed percentage reaches zero. It happens most often on the R1's convertible tablet mode where the display brightness is high. Run two full calibration cycles — discharge fully to hibernate, then charge to 100% — so the fuel gauge IC maps the new cell's actual voltage curve. After calibration, shutdowns at falsely high percentages stop.