Asus A31-JN101 Laptop Replacement Battery 10.8V 2400mAh

Asus JN101 — 10.8V Li-ion Replacement Battery (A31-JN101)

This is a 10.8V, 2400mAh (25.92Wh) Li-ion battery for the Asus JN101 netbook. It slots in where the original A31-JN101 cell sits and restores portable power to the machine. If your current battery no longer holds a charge or the system shuts off unexpectedly, this is the correct replacement cell.

• JN101 netbook compatibility: The JN101 runs a low-voltage Atom-class platform that draws a consistent current profile. The A31-JN101 part number maps directly to the connector pinout and BMS handshake voltage range this platform expects — no adapters or modifications needed.
• Bench tested on actual hardware: We ran this cell through a full charge and discharge cycle on the bench. The BMS responded correctly at both ends — charge termination triggered cleanly at 12.6V and the low-voltage cutoff held at the expected floor without tripping prematurely under load.
• Post-install recalibration on the JN101: After fitting this battery, run one full discharge until the system hibernates on its own, then charge uninterrupted to 100%. This resets the BIOS battery learn cycle and clears the inaccurate health warning that appears after a cell swap.

Why the JN101 BIOS flags a new battery as poor health immediately after swap

The JN101 stores battery health data in EEPROM on the original cell. When a new cell goes in, the BIOS reads no matching historical data and defaults to a poor health or unknown status flag. This is not a fault with the replacement cell — it is the BIOS reacting to a blank slate. Running one complete learn cycle (full discharge to hibernate cutoff, then uninterrupted charge to 100%) writes fresh calibration data and clears the flag. After two to three cycles the reported health figure stabilises.

Fuel gauge jumping erratically in the first few cycles after replacement

The fuel gauge IC on the JN101 estimates state-of-charge by tracking voltage curves it learned from the old cell. A new cell has a slightly different discharge curve, so the gauge reads inaccurately — jumping from 60% to 20% or stalling at a fixed number. This is a calibration gap, not a faulty battery. Run two or three full charge-discharge cycles and the IC relearns the curve against the new cell. By the third cycle the gauge should track within a few percent of actual capacity.