ND40 Motorola Moto Edge 30 Replacement Battery 3.89V 3900mAh

Motorola Moto Edge 30 / XT2203 — 3.89V Li-Polymer Replacement Battery (ND40 / SB18D34507)

This 3.89V, 3900mAh (15.17Wh) lithium-polymer cell replaces the original ND40 battery in the Motorola Moto Edge 30, Moto Edge 30 5G, and XT2203 series smartphones. It restores power to the processor, display, and cellular radios when the original cell has degraded below usable capacity. Voltage and connector match the stock specification — no modifications needed.

• Moto Edge 30 / XT2203 platform fit: These model variants share the same battery bay geometry, flex connector pinout, and BMS handshake protocol. The ND40 part number applies across the standard and 5G SKUs because Motorola used a unified power rail at 3.89V nominal across this sub-family.
• Bench tested on actual hardware: We cycled this cell through full charge and discharge on a Moto Edge 30 unit. The BMS accepted the cell without flagging an unrecognised pack error, and the charge IC stepped through trickle, constant-current, and constant-voltage phases as expected.
• Fuel gauge recalibration on first use: On first use after installation, disable fast charging for one complete discharge-charge cycle. The fuel gauge IC is still calibrated to the old cell's discharge curve — running a slow cycle first lets the coulomb counter map the new cell before high-current charging begins.

Sudden shutdown at 20–30% on the Moto Edge 30 after a cell swap

This is a voltage-cliff problem, not a capacity problem. The fuel gauge IC still references the old cell's discharge curve, so it reports 25% remaining while the actual cell voltage has already dropped below the modem and display load threshold — typically around 3.5V under peak draw. The BMS triggers an emergency cutoff because the real cell voltage cannot sustain the load, even though the OS display says there is charge left. One full slow discharge-to-shutdown followed by a full charge resets the coulomb counter and realigns the percentage readout to the new cell.

USB-PD fast charge not activating after replacement

On the first charge cycle with a new cell, the charge IC sometimes does not negotiate the fast-charge protocol because the BMS presents higher impedance than the original aged cell. The charger detects this mismatch and falls back to standard 5V charging as a precaution. This is not a fault with the replacement cell — it typically resolves after the first full standard charge cycle. Use the stock Motorola charger for that first cycle, then attempt fast charging on the second cycle at a full 0% to 100% run.