Nokia BN-01 X Smartphone Replacement Battery 3.7V 1500mAh

Nokia X / A110 Series — 3.7V Li-ion Replacement Battery (BN-01)

This is a 3.7V, 1500mAh Li-ion cell built to the BN-01 spec, fitting the Nokia X, X+, A110, and Normandy handsets. It slots into the original battery bay using the same connector footprint and contact layout as the factory cell. Capacity figures come from the product data, not third-party estimates.

• Nokia X and A110 platform fit: These models share the BN-01 form factor — same 69.40 × 34.00 × 5.20mm shell, same three-pin connector, and the same BMS handshake the charge IC expects. Swapping across any of these variants does not require firmware changes or connector adapters.
• Bench tested on actual hardware: We cycled this cell on a Nokia X unit, monitoring BMS cutoff at both the low-voltage floor and charge-termination threshold. The protection circuit tripped correctly at the expected voltage limits with no false positives under screen and modem load.
• Fuel gauge recalibration on first cycle: After fitting this cell, run one full discharge to automatic shutdown — do not force-power-off — then charge uninterrupted to 100%. The Nokia X fuel gauge IC reads the discharge curve to build its capacity model. Skip this step and the percentage readout will drift from the first day.

Why the Nokia X reports the wrong battery percentage after a cell swap

The Nokia X uses a coulomb-counter fuel gauge that was calibrated against the original cell's discharge curve over many cycles. Installing a new cell resets the physical chemistry but not the IC's learned model. Until the gauge runs at least one full uninterrupted discharge-to-shutdown and a complete recharge, it compares current draw against stale data. This produces percentage jumps of 10–15% and premature low-battery warnings that disappear after one or two full cycles.

Sudden shutdown at 20–30% on the replacement cell

This happens when the cell voltage drops below the modem's minimum rail — typically around 3.2V — faster than the fuel gauge predicts. A fresh cell has higher internal resistance than a broken-in cell, so voltage sag under peak load is steeper. The OS reads 25% remaining, but the instantaneous voltage under a 3G or LTE burst hits the BMS cutoff and the phone dies. After two to three full charge cycles, internal resistance drops and the shutdowns stop.