About this replacement
Sony VAIO FIT 14E / FIT 15E — 14.8V Li-ion Replacement Battery (VGP-BPS35)
This is a 14.8V, 2200mAh (32.56Wh) Li-ion replacement battery for the Sony VAIO FIT 14E and FIT 15E series laptops. It replaces OEM part numbers VGP-BPS35 and VGP-BPS35A. Fits a broad range of SVF-prefix VAIO models including the SVF14215SC and SVF1421E2E.
- FIT 14E and FIT 15E platform fit: Both the 14-inch and 15-inch FIT series share the same battery bay geometry, connector pinout, and BMS handshake protocol — that is why one cell covers both screen sizes without modification.
- Bench tested on actual hardware: We ran this cell through charge and discharge cycles on a VAIO FIT platform. The BMS communicated correctly with the BIOS, charge acceptance was normal, and no protection cutoff trips occurred under mixed CPU and display load.
- First-cycle reset after install: After fitting this battery, run the laptop down to hibernate-level cutoff, then charge it uninterrupted to 100%. This forces the BIOS to run its battery learn cycle against the new cell and clears the inaccurate health warning that appears after every cell swap on VAIO hardware.
Why the VAIO FIT BIOS flags a new battery as poor health immediately after swap
The VAIO firmware stores charge history and wear data in EEPROM on the battery itself. When a new cell arrives, that EEPROM is blank or carries factory default values the BIOS does not recognise as a healthy profile. The system reads this as degraded rather than new. Running one full discharge-to-hibernate followed by an uninterrupted charge to 100% writes a fresh learn-cycle baseline. After that cycle, the health indicator updates correctly.
Laptop shuts down at 20–30% charge shown on the VAIO FIT
This happens when the fuel gauge IC has not yet calibrated against the new cell's actual voltage curve. The gauge reports 20–30% remaining, but the cell hits its low-voltage cutoff under full CPU and display load before the estimate catches up. It is a calibration lag, not a faulty battery. Complete two full discharge-to-hibernate and full-recharge cycles — the fuel gauge re-maps the curve and the shutdowns stop. After calibration, verify the system reads above 14.4V at full charge in BIOS hardware monitor.