Clevo P870BAT-8 Replacement Battery 15.12V 5800mAh

Clevo P870TM-G Series — 15.12V Li-ion Replacement Battery (P870BAT-8)

This is a 15.12V, 5800mAh (87.7Wh) Li-ion replacement battery for the Clevo P870TM-G gaming laptop and compatible models including the P870DM3-G, P775DM3, and P870DM2. It uses OEM part numbers P870BAT-8, 6-87-P870S-4271, 6-87-P870S-4272, 6-87-P870S-4273, and 6-87-P870S-4273A. This cell restores cordless operation when the original pack has degraded or failed outright.

• P870 platform compatibility: The P870, P870DM, P870DM2, P870DM3-G, and P870TM-G all share the same 15.12V four-cell architecture, connector pinout, and BMS handshake protocol. A single cell revision covers the full range because the charge controller and protection circuit board spec did not change across these board revisions.
• Bench tested on actual hardware: We ran this cell through a full charge and load cycle on P870-series hardware. The BMS communicated correctly with the system board, charge current stepped down normally at 15.12V, and thermal protection triggered as expected under sustained GPU plus CPU load — no false cutoffs recorded.
• Post-installation discharge cycle: After fitting this cell, run the laptop on battery until it hibernates at its low-voltage cutoff, then charge uninterrupted to 100%. This forces the BIOS battery learn cycle to reset against the new cell data and clears the inaccurate health warning that appears in most system utilities after every cell swap on this platform.

Why the P870TM-G shuts down at 20–30% after a battery swap

The P870TM-G pulls heavy current when the CPU and discrete GPU both hit full load simultaneously. If the new cell has not been calibrated against the system's fuel gauge IC, the BIOS uses discharge curve data from the old, degraded cell to predict remaining capacity. That prediction runs out fast under load, and the system shuts down even though actual charge remains in the cell. Running two or three full discharge-to-hibernate and charge-to-100% cycles forces the fuel gauge IC to build a new discharge map against the replacement cell's actual chemistry. After calibration, the shutdown-at-30% behaviour stops.

BIOS reporting battery health as poor or "unknown" immediately after replacement

This happens because the BIOS reads health data from an EEPROM register that still holds degradation values written by the old cell. The new cell's physical capacity is fine — the register simply has not been overwritten yet. Perform one complete charge-to-100% cycle, then let the laptop discharge to hibernate cutoff without interruption. On the next full charge the BIOS re-writes the health register from fresh cycle data, and the "poor" or "unknown" status clears. If it persists after two full cycles, enter the BIOS battery utility and trigger a manual learn cycle from the Power menu.