About this replacement
Sony VAIO Pro 11 — 7.5V Li-Polymer Replacement Battery (VGP-BPS37)
This is a 7.5V, 4120mAh (30.9Wh) Li-Polymer battery for the Sony VAIO Pro 11 ultrabook. It fits SVP1121ZPWR, SVP11217PW/B, SVP11216CW, and 76 additional SVP11-series configurations. It replaces the original VGP-BPS37 cell directly.
- SVP11-series compatibility: All SVP11 variants share the same 7.5V two-cell Li-Polymer architecture, flat-pack form factor, and proprietary SMBus connector. The battery management circuit communicates charge state and health data directly to the VAIO EC firmware, so voltage, connector, and BMS protocol must all match — and they do across this entire model range.
- Bench tested on actual hardware: We ran this cell on an SVP1121ZPWR under combined CPU and display load. The BMS held steady above the low-voltage cutoff threshold, charge acceptance reached full capacity without throttling, and the SMBus handshake completed without fault codes on the first cycle.
- First-cycle discharge on the VAIO Pro 11: After installation, run one full discharge down to hibernate cutoff, then charge uninterrupted to 100%. This triggers the VAIO BIOS battery learn cycle, resets the fuel gauge IC baseline against the new cell, and clears the spurious "battery health poor" warning that appears after every cell swap on this platform.
BIOS reporting poor battery health immediately after fitting the VGP-BPS37
The VAIO Pro 11 BIOS reads health data from EEPROM registers written by the original cell during its service life. A new cell ships with factory EEPROM values that do not match the learned discharge curves stored in the system. Until the BIOS completes a full learn cycle against the new chemistry, it flags the battery as degraded. This is a firmware calibration state, not a fault. Run one full discharge to hibernate, charge to 100% without interruption, and the BIOS will rewrite its health register against the new cell data.
VAIO Pro 11 shutting down at 20–30% charge shown on screen
This happens when the fuel gauge IC still holds calibration data from the old, degraded cell. The displayed percentage is calculated against the old cell's discharge curve, so 20–30% on screen can represent the actual voltage floor of the new cell under combined CPU and display load. The laptop hits the hardware low-voltage cutoff before the gauge reaches 0%. Force a complete discharge to hibernate cutoff twice in succession — this forces the fuel gauge IC to recalculate capacity endpoints against the new cell and aligns the displayed percentage with actual cell voltage.