About this replacement
Lenovo IdeaPad Miix 720-12IKB — 7.68V Li-Polymer Replacement Battery (5B10L72502)
This 7.68V, 5300mAh (40.7Wh) Li-Polymer cell replaces the internal battery in the detachable screen unit of the Lenovo IdeaPad Miix 720-12IKB. It covers all 80VV variants, including the 80VV002JGE. Compatible OEM part numbers include 5B10L72502, 5B10W89300, L15L4PC3, L15M4PC3, and SB10W89296.
- Miix 720-12IKB screen-unit compatibility: All 80VV variants share the same 7.68V battery rail, connector pinout, and BMS handshake protocol. The same cell fits every sub-model in this series without hardware modification.
- Bench tested on actual hardware: We ran this cell through charge, discharge, and reconnect cycles on the Miix 720 screen unit. The BMS negotiated correctly with the system firmware and reported accurate state-of-charge data from the first cycle.
- BIOS learn cycle after installation: After fitting the new cell, run one full discharge down 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.
BIOS reporting poor battery health immediately after fitting the new cell
The Miix 720 BIOS reads health data from EEPROM registers written by the original factory cell. When a new cell is installed, those registers still hold degraded values from the old battery. The system flags poor health before the new cell has completed a single cycle. Running the full discharge-to-hibernate then uninterrupted charge sequence overwrites the learn-cycle data and clears the warning. After two complete charge cycles, the BIOS health indicator should return to normal.
Miix 720 shutting down at 20–30% battery shown on screen
This happens when the fuel gauge IC has not yet calibrated against the new cell's actual voltage curve. The IC still maps capacity against the old cell's depleted profile, so it reads 20–30% remaining when the cell voltage is already near cutoff under combined CPU and display load. The fix is a full calibration cycle: discharge until the device hibernates on its own, then charge to 100% without interruption. After two to three of these cycles, the fuel gauge aligns to the new cell and the premature shutdown stops.