Wind Blade Smartphone Replacement Battery 3.7V 1300mAh

Wind Blade — 3.7V Li-ion 1300mAh Replacement Battery

This is a 3.7V, 1300mAh lithium-ion cell for the Wind Blade smartphone. It replaces the original battery when capacity has dropped to the point where the phone no longer holds a usable charge. Dimensions are 43.50 × 47.00 × 6.10mm — verify against your existing cell before installing.

• Wind Blade fit: The Blade line uses a compact low-voltage single-cell pack at 3.7V nominal. This cell matches that voltage rail and connector footprint, so the charge IC sees the correct input parameters on first power-up.
• Bench tested on actual hardware: We cycled this cell through charge and discharge under load. The BMS held cutoff correctly at both the low-voltage floor and the 4.2V charge ceiling, with no thermal anomalies reported at the charge IC.
• Fuel gauge recalibration on first use: On first use after installation, disable fast charging and run one full discharge-to-charge cycle. This lets the fuel gauge IC build an accurate discharge curve against the new cell before the charge IC starts pushing higher current into it.

Why the Wind Blade reports wrong battery percentage after a cell swap

The Blade's fuel gauge IC stores a learned discharge curve from the original cell. When a new cell goes in, that stored curve no longer matches the actual cell chemistry and internal resistance. The OS reads state-of-charge from the fuel gauge, not the cell directly, so the percentage shown can be 15–20% off in either direction. One complete discharge below 5% followed by a full charge to 100% resets the coulomb counter and lets the IC re-learn the curve.

Sudden shutdown at 20–30% on the replacement cell

This happens when the phone's modem or display draws a current spike the new cell cannot sustain at that state of charge. Voltage drops momentarily below the BMS protection threshold — around 3.0V — and the BMS cuts output to protect the cell. The OS never sees a graceful shutdown signal, so it logs it as a crash. The fix is the same recalibration cycle: fully discharge the phone until it shuts itself off, then charge uninterrupted to 100% so the fuel gauge IC maps the actual voltage cliff of this specific cell.