About this replacement
Toshiba Satellite 1955-S807 Series — 14.8V Li-ion Replacement Battery (PA3206U-1BRS)
This 14.8V, 6600mAh Li-ion battery replaces the original pack in Toshiba Satellite 1950 and 1955 series laptops. It fits the Satellite 1955-S807, 1955-S804, 1955-S801, 1950-801D, and eight additional variants sharing the PA3206 battery platform. Capacity figures come from the product data — 97.68Wh total energy.
- Satellite 1950/1955 platform fit: These models share the same 14.8V four-cell bus, PA3206 connector pinout, and BMS handshake protocol — which is why one part number covers the full range. The BMS communicates state-of-charge data over the SMBus line to the Toshiba EC firmware.
- Bench tested on actual hardware: We cycled this cell through charge and discharge on the Satellite platform and logged BMS communication at each stage. The protection circuit held the charge termination voltage correctly and discharged without premature cutoff under sustained CPU and display load.
- First-cycle calibration on the Satellite 195x EC: After installing, run one full discharge down to hibernate cutoff, then charge uninterrupted to 100%. This forces the Toshiba embedded controller to run its battery learn cycle against the new cell, clearing the inaccurate health warning that appears after every pack swap.
Why the Satellite 1955 BIOS flags a new battery as poor health
The Toshiba EC stores learned capacity data from the previous cell in non-volatile memory. When a new pack is installed, the EC compares its EEPROM baseline against the new cell's reported state — which starts at zero learned cycles. The mismatch triggers a "battery needs replacement" or low health flag even when the cell is brand new. Running the full discharge-to-hibernate then uninterrupted charge cycle rewrites that EC baseline and clears the warning.
Satellite 1955 shutting down at 20–30% charge shown on screen
This happens when the fuel gauge IC has not yet calibrated against the new cell's actual voltage curve. The IC maps percentage to voltage based on old data, and the new cell hits its low-voltage cliff at a different point than expected. Under full CPU and display load, the voltage drop is steep — the BMS trips before the screen gauge catches up. Run two full discharge-to-hibernate and charge-to-100% cycles; after the second cycle the fuel gauge IC recalibrates and the shutdown point moves back toward 5–8% where it belongs.