BLU EZ2Go N4U85T Replacement Battery 3.7V 1200mAh

BLU EZ2Go — 3.7V Li-ion Replacement Battery (N4U85T)

This is a 3.7V, 1200mAh Li-ion cell that replaces the original N4U85T battery in the BLU EZ2Go smartphone. It fits directly into the EZ2Go's battery bay and connects via the stock ribbon connector. Capacity figure is taken from the product specification — 4.44Wh total energy.

• EZ2Go platform fit: The EZ2Go uses a fixed 3.7V nominal rail with a single-cell Li-ion architecture. This replacement matches that voltage rail and the original connector pinout, so the phone's charge IC sees the new cell the same way it saw the factory cell.
• Bench tested on actual hardware: We cycled this cell through charge and discharge on the bench. The BMS accepted charge termination correctly at 4.2V and held cutoff at 3.0V under load without tripping early.
• Fuel gauge recalibration after swap: On first use after installation, disable fast charging if the option is available and run one full discharge-charge cycle before resuming normal use. This gives the EZ2Go's fuel gauge IC time to map its coulomb counter against the new cell's discharge curve before high-current charging begins.

Sudden shutdown at 20–30% on the BLU EZ2Go after a cell swap

This happens when the fuel gauge IC is still reading the old cell's discharge curve against the new cell's actual voltage behaviour. As the new cell drops toward 3.5V under modem or screen load, the voltage sags faster than the IC predicts. The phone reads 25% on screen but the cell voltage has already crossed the hardware cutoff threshold. One full discharge-to-shutdown followed by a complete charge cycle resets the coulomb counter and clears this.

BLU EZ2Go not powering on after sitting in storage

If a replacement cell has been stored discharged for several months, its resting voltage can fall below 2.5V. At that level the BMS locks out to prevent damage, and the phone shows nothing when you press power. Connect the phone to a wall charger — not a USB port — and leave it for 20–30 minutes without pressing anything. The charge IC will push a low-current trickle into the cell until it recovers above 2.9V, at which point the BMS re-initialises and normal charging resumes.