About this replacement
Positivo Master N40i / Motion Series — 7.4V Li-Polymer Replacement Battery (88R-S147G3-2603)
This 7.4V, 3000mAh (22.2Wh) Li-Polymer cell replaces the original battery in the Positivo Master N40i, Motion C432a, Motion C4500ai, Motion C464a, and eight additional Motion series models. It restores untethered operation when the original cell has degraded or failed to hold a charge. Voltage and connector match the OEM specification for these notebooks.
- Motion and Master N40i platform fit: These Positivo models share the same 7.4V two-cell Li-Polymer architecture, connector pinout, and BMS handshake protocol — which is why a single cell covers the full range. The BMS communicates over SMBus, and this replacement carries a compatible EEPROM data block to pass that handshake on first boot.
- Bench tested on actual hardware: We ran charge and discharge cycles through the BMS and confirmed the protection circuit triggers correctly at low-voltage cutoff. The cell reached rated capacity within three cycles and the SMBus handshake cleared without error on each test unit.
- Post-install calibration for the Master N40i: After fitting this cell, run the laptop down to hibernate cutoff on a single discharge, then charge uninterrupted to 100%. This forces the BIOS battery learn cycle to reset against the new cell and clears the inaccurate health warning that appears on the first boot after any cell swap.
Why the Master N40i shuts down at 20–30% after a battery swap
The BIOS fuel gauge IC builds a discharge curve map against the previous cell over hundreds of cycles. When a new cell goes in, that map no longer matches the actual voltage curve of the fresh chemistry. The laptop hits a voltage point the firmware wrongly interprets as empty and forces shutdown — even though the cell still has capacity. Running two full discharge-to-hibernate then full-recharge cycles gives the fuel gauge IC enough data to remap to the new cell and stop the premature cutoff.
BIOS reporting the replacement battery as "0%" or "unknown" on first boot
This is an EEPROM mismatch — the BIOS is reading state-of-charge data cached from the old cell and applying it to the new one. The display reads 0% or "unknown" because the cached value is stale, not because the cell is actually empty. Plug in the AC adapter and let the laptop charge without interruption to 100%, then complete one full discharge to hibernate. After that cycle, the BIOS recalibrates its read from the live cell data and the percentage display returns to accurate. Target a full charge reading of 8.3–8.4V across the pack terminals to confirm the cell is functioning correctly.