About this replacement
Toshiba Portege 7140CT Series — 10.8V Li-ion Replacement Battery (PA2505)
This 10.8V, 6000mAh Li-ion battery replaces the original cell in the Toshiba Portege 7140CT and related Portege 7000 series notebooks. It fits models including the 7000, 7020CT, and 7220CT, all sharing the same OEM part numbers PA2505, PA3000U-1BRS, and PA3001U-1BRM. Total rated energy is 64.8Wh.
- Portege 7000 series compatibility: The 7000, 7020CT, 7140CT, and 7220CT share a common 10.8V battery bay, connector pinout, and BMS handshake protocol — that is why a single cell part number covers the full range.
- Bench tested on actual hardware: We ran this cell through charge and discharge cycles on a Portege 7000 series unit. The BMS communicated correctly, charge current ramped normally through CC/CV stages, and the protection circuit tripped at the expected low-voltage cutoff without hard shutdown.
- First-cycle reset on Portege 7000 series: After installing, run one full discharge to hibernate cutoff, then charge uninterrupted to 100%. This forces the BIOS battery learn cycle to reset against the new cell, clearing the inaccurate health warning that appears after every cell swap on this platform.
Why the Portege 7140CT BIOS reports poor battery health after a cell swap
The Portege 7000 series BIOS stores learned battery data — charge capacity, cycle count, and health status — in EEPROM on the old cell. When a new cell is installed, the BIOS reads stale EEPROM values and flags the battery as degraded even though the new cell is unused. This is not a fault with the replacement. Running a full discharge-to-hibernate followed by a complete uninterrupted charge lets the BIOS relearn the cell's actual capacity and clears the warning. After two or three full cycles, the health indicator stabilises at the correct value.
Portege 7140CT shutting down at 20–30% charge shown on screen
This happens when the fuel gauge IC's calibration data no longer matches the new cell's discharge curve. The gauge was trained against the old degraded cell and miscalculates remaining charge on the new one. Under full CPU and display load, the actual cell voltage drops below the protection threshold before the gauge reaches zero, triggering a hard shutdown. Run two complete discharge-to-hibernate and full recharge cycles — the fuel gauge IC recalibrates against the new cell's curve and the cutoff point moves back to the correct level near 3.0V per cell.