Vodafone SEBA01 Replacement Battery 3.7V 900mAh Li-ion

Vodafone SEBA01 — 3.7V Li-ion Replacement Battery

This is a 3.7V, 900mAh Li-ion replacement battery for Vodafone mobile handsets using the SEBA01 cell. Original batteries in this class lose usable capacity after 300–500 charge cycles, leaving the phone unable to hold charge through a normal day. This cell restores that capacity to factory spec.

• SEBA01 platform fitment: Vodafone handsets sharing this part number use a matched voltage rail and connector pinout. The BMS on these devices checks cell impedance on first boot — a cell outside the accepted range will trigger a charging fault. This replacement passes that handshake.
• Bench tested on actual hardware: We ran this cell through charge termination, overvoltage protection, and short-circuit cutoff. The BMS capped charge at 4.2V and tripped the protection circuit correctly under load fault conditions.
• Fuel gauge recalibration on first use: On first use after installation, disable fast charging for one complete discharge-charge cycle. This lets the fuel gauge IC recalibrate against the new cell's discharge curve before high-current charging pushes current into an uncalibrated cell — preventing erratic percentage readings from the first charge onward.

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 higher internal impedance near depletion, so the IC learned to cut off early. When the new cell hits the same state-of-charge region, the phone reads the voltage profile as critically low and shuts down — even though capacity remains. One full discharge-charge cycle without interruption resets the coulomb counter and corrects the threshold. After that cycle, shutdowns at 20–30% should stop.

Phone will not power on after the battery sat in storage

Li-ion cells discharged below 2.5V per cell trigger a BMS lockout — the protection circuit opens and the phone will not respond to a charger or the power button. Connect the phone to a wall charger, not a USB port, and leave it for 20–30 minutes without pressing anything. The charger's trickle current slowly raises cell voltage above the 2.5V threshold, which prompts the BMS to re-initialise and allow normal charging to resume. If the phone still shows no response after 30 minutes, check that the charge cable seats fully in the port.