About this replacement
Lenovo Yoga 3 Pro 1370 — 7.7V Li-Polymer Replacement Battery (L13M4P71)
This is a 7.7V 5800mAh (44.66Wh) Li-Polymer battery for the Lenovo Yoga 3 Pro ultrabook convertible. It fits the Yoga 3 Pro 1370 and related 13.3-inch variants, including the Pro-I5Y70(D) series. Part numbers L13M4P71, L14S4P71, and 121500264 all cross-reference to this cell configuration.
- Yoga 3 Pro 1370 platform fit: These models share a common 7.7V two-cell Li-Polymer architecture with the same flat-pack form factor (294.60 × 163.50 × 2.80mm) and a matching connector pinout. The BMS handshake uses EEPROM data the firmware reads at POST — swapping cells from any of these variants works because the voltage rail and communication protocol are identical across the 1370 series.
- Bench tested on actual hardware: We ran this cell through charge and discharge cycles on a Yoga 3 Pro 1370 unit. The BMS accepted the EEPROM handshake without fault codes, the charge controller reached full cutoff correctly, and the cell held voltage under CPU and display load without sagging below the BMS low-voltage threshold.
- Post-swap calibration on the Yoga 3 Pro: After fitting this battery, run the Yoga 3 Pro down to hibernate cutoff under normal load — do not force-shutdown. Then charge uninterrupted to 100%. This clears the BIOS battery learn cycle from the old cell and removes the inaccurate health warning that appears after every cell swap on this platform.
BIOS reporting poor battery health immediately after fitting a new cell
The Yoga 3 Pro stores battery health metrics in EEPROM on the battery controller, not in the BIOS chip itself. When you swap the cell, the firmware reads stale cycle-count and capacity data from the old EEPROM signature and flags the new battery as degraded. This is not a fault with the replacement cell — it is a calibration mismatch. Run one full discharge to hibernate cutoff, then a complete uninterrupted charge to 100%, and the BIOS health indicator will reset to normal.
Yoga 3 Pro shutting down at 20–30% charge shown on screen
This happens when the fuel gauge IC is still calibrated to the old cell's discharge curve. Under combined CPU and display load, the new cell briefly sags in voltage, and the uncalibrated gauge reads that sag as a critically low state of charge — triggering an immediate shutdown. The fix is two to three full discharge-and-charge cycles so the fuel gauge IC maps its thresholds to the new cell's actual voltage profile. After those cycles, the percentage readout stabilises and the early shutdowns stop.