BV-5J Nokia Lumia 435 Compatible Battery 3.7V 1550mAh

Nokia Lumia 435 / Lumia 532 — 3.7V Li-ion Replacement Battery (BV-5J)

This is a 3.7V, 1550mAh Li-ion battery for the Nokia Lumia 435, Lumia 532, and RM-1070. It replaces the original BV-5J cell when the factory battery degrades, swells, or no longer holds a usable charge. Rated at 5.74Wh, it restores full power to the device without replacing the handset.

• Lumia 435, 532, and RM-1070 fitment: All three models share the same chassis width, connector pinout, and BMS communication protocol. The BV-5J form factor — 60.10 × 38.10 × 5.60 mm — seats flush in each bay without modification.
• Bench tested on actual hardware: We ran this cell through a full charge and discharge cycle on a Lumia 435 unit. The BMS accepted the new cell on first contact, reported voltage correctly, and did not trigger a protection cutoff during the discharge sweep.
• Fuel gauge recalibration on first use: After installation, disable fast charging and run one complete discharge-to-charge cycle before normal use. This gives the fuel gauge IC time to map the new cell's discharge curve. Skipping this step is the main reason percentage readings jump erratically in the first two days.

Sudden shutdown at 20–30% on the Lumia 435 after a cell swap

This happens when the fuel gauge IC is still calibrated to the old cell's voltage curve. The new cell hits a voltage cliff under modem or screen load at a point the IC does not expect. The phone interprets it as a fault and cuts power to protect the SoC. One full discharge-to-charge cycle without fast charging corrects the calibration, and the shutdowns stop.

Phone runs warm near the battery during the first charge after replacement

A new cell starts with slightly higher internal impedance than a broken-in one. The charge IC on the Lumia 435 pushes current at a fixed rate, and the higher impedance converts more of that energy to heat on the first cycle. This is normal and resolves after one to two full cycles as the cell conditions. If the back stays warm through the third charge, check that no third-party fast-charge adapter is bypassing the standard 5V/1A input path — hold input voltage to 5V for the first three cycles.