ZTE Blade 3.7V 1300mAh Replacement Battery Li-ion

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

This is a 3.7V Li-ion cell rated at 1300mAh (4.81Wh), built to replace the original battery in the ZTE Blade smartphone. It fits the Blade platform directly and restores power to a phone that no longer holds a charge or fails to power on. Install it when the original cell has degraded past the point of useful daily capacity.

• ZTE Blade platform fit: The Blade series shares a consistent battery bay geometry and connector orientation across its base lineup. This cell matches those physical dimensions — 43.50 x 47.00 x 6.10mm — and the 3.7V nominal voltage the phone's power management IC expects.
• Bench tested on actual hardware: We ran this cell through charge and discharge cycles on the bench and confirmed the BMS communicates correctly with the phone's charge IC. The cell accepts charge without triggering overcurrent cutoff and holds voltage across a full discharge curve.
• Fuel gauge recalibration after swap: On first use after installation, disable fast charging and run one complete discharge-charge cycle at standard current. This lets the fuel gauge IC map the new cell's discharge curve before fast-charge current is applied to an uncalibrated cell.

Sudden shutdown at 20–30% on the replacement cell

This happens when the fuel gauge IC is still calibrated to the old cell's discharge curve. The old cell had a steeper voltage drop near depletion — the gauge was trained to that profile. A new cell holds voltage higher for longer, then drops sharply. The phone sees that drop as a low-voltage shutdown event even though the percentage readout still shows 20–30%. One full discharge-to-shutdown followed by a full charge corrects the coulomb counter and eliminates premature cutoffs.

Phone reports wrong battery percentage after cell swap

The ZTE Blade uses a fuel gauge IC that tracks charge state against a stored discharge curve from the previous cell. After a replacement, the stored curve no longer matches the new cell's actual voltage behaviour. This causes erratic percentage jumps — commonly from 50% straight to 15%, or a freeze at one value for extended periods. Discharge the phone fully until it shuts itself off, then charge uninterrupted to 100% to force the IC to relearn against the new cell.