Twinhead SlimNote 700 Series Replacement Battery DR35 10.8V 4000mAh

Twinhead SlimNote 700 Series — 10.8V Ni-MH Replacement Battery (DR35)

This is a 10.8V, 4000mAh Ni-MH replacement battery for the Twinhead SlimNote 700 Series notebook computers. It fits the SlimNote 710CV and SlimNote 713TV as well as the broader 700 Series line. The OEM part numbers covered are DR35, DR35AA, and DR35S.

• SlimNote 700 Series platform fit: The 710CV and 713TV share the same battery bay geometry, connector pinout, and BMS handshake protocol as the wider 700 Series. One cell covers all three variants without modification.
• Bench tested on actual hardware: We cycled this cell through charge and discharge on the SlimNote platform. The BMS accepted the cell without error flags, and the charge controller reached termination voltage cleanly on the first cycle.
• Ni-MH conditioning after swap: After installing, 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 typically appears after every cell swap on this platform.

BIOS reporting battery health as poor after replacing the DR35

The SlimNote BIOS stores battery health data in EEPROM tied to the original cell. When a new cell goes in, the BIOS compares current readings against that stored data and flags a mismatch as poor health. This is not a fault with the replacement cell — it is stale EEPROM data from the old battery. Running a full discharge-to-hibernate followed by an uninterrupted full charge completes one learn cycle. After two to three cycles, the BIOS recalibrates and the health warning clears.

SlimNote shutting down at 20–30% charge shown on screen

This happens when the cell voltage drops sharply under the combined load of the CPU and display — a voltage cliff specific to Ni-MH cells that have not been calibrated to the fuel gauge IC. The OS fuel gauge was trained on the old cell's discharge curve, so it misreads the new cell's actual remaining capacity. The laptop hits the hardware low-voltage cutoff before the displayed percentage reaches zero. Run two full discharge-to-hibernate cycles followed by full uninterrupted charges, and the fuel gauge IC will remap to the new cell's curve — the cutoff point should align with a displayed level below 10%.