Yakumo LIP8020 Replacement Battery 14.8V 4400mAh Li-ion

Yakumo Q5M Basic YW / Q7M — 14.8V Li-ion Replacement Battery (LIP8020)

This is a 14.8V, 4400mAh (65.12Wh) Li-ion battery for the Yakumo Q5M Basic YW, Q7M, and Mobilium ATI 350 YW notebooks. It replaces OEM part numbers LIP8020, LIP8082, EM-G320L1, EM-G320L2, ES1-2200, and ES1-4400. If your original cell no longer holds charge or has degraded to the point the laptop won't leave the desk, this is the direct swap.

• Q5M Basic YW, Q7M, and Mobilium ATI 350 YW compatibility: These models share the same 14.8V four-cell series architecture, connector pinout, and BMS handshake protocol — which is why a single part number spans all three. The charge controller recognises the same communication signal across each chassis variant.
• Bench tested on actual hardware: We cycled this cell through charge-to-cutoff and discharge-to-hibernate on the Q7M platform. The BMS communicated correctly with the system board, charge acceptance was normal across all four cells, and no thermal flags were triggered under sustained CPU and display load.
• First-cycle conditioning on Yakumo notebooks: After fitting, run one full discharge to hibernate-cutoff, then charge uninterrupted to 100% without using the machine. This forces the BIOS battery learn cycle to reset against the new cell chemistry and clears the inaccurate health warning that appears after every cell swap on this platform.

Why the Q5M and Q7M shut down at 20–30% battery shown

This happens when the fuel gauge IC is still calibrated to the old, degraded cell. The new cell has higher capacity, but the IC's internal map still expects the old voltage curve. Under full CPU plus display load, the system reads a voltage that maps to near-empty on the old curve and triggers an emergency shutdown — even though actual charge remains. Running two or three full discharge-to-hibernate cycles recalibrates the IC against the new cell and eliminates the premature cutoff. After calibration, the gauge will track accurately down to approximately 10.8V per cell before a real low-battery event occurs.

BIOS reports battery health as "poor" or "unknown" immediately after installation

The Yakumo BIOS reads health data from EEPROM registers stored on the battery's protection circuit, not from a live capacity measurement. A new cell ships with factory EEPROM defaults that don't match the learned values the BIOS accumulated from the old cell — so it flags the health status as degraded or unrecognised. This is not a fault with the replacement cell. To clear it, complete the first-cycle conditioning described above; one full learn cycle rewrites the relevant BIOS registers and the health indicator returns to normal. If the warning persists after two full cycles, confirm the BIOS firmware is on the latest available version for the Q5M or Q7M.