BLP537 Oppo U705W Replacement Battery 3.8V 2020mAh

Oppo U705W / Ulike 2 — 3.8V Li-Polymer Replacement Battery (BLP537)

This is a 3.8V, 2020mAh Li-Polymer cell (7.68Wh) carrying OEM part number BLP537. It fits the Oppo U705W, Ulike 2, U705T, and Find Way series smartphones. Swap it in when the original cell no longer holds adequate charge through a normal day.

• U705W / Ulike 2 / U705T / Find Way compatibility: These models share the same 3.8V single-cell architecture, BLP537 connector footprint, and charge IC handshake — one cell covers all of them without modification.
• Bench tested on actual hardware: We cycled this cell through charge and load on the U705W platform. The BMS accepted the charge IC handshake cleanly, held voltage above the cutoff threshold under screen-on modem load, and did not trigger a protection trip at any point in the test sequence.
• Fuel gauge recalibration on first use: After fitting this cell, disable fast charging and run one full discharge-charge cycle before returning to normal use. The U705W fuel gauge IC was calibrated to the old cell's discharge curve — one unconstrained cycle lets it remap against the new BLP537 and stops erratic percentage readings early on.

Sudden shutdown at 20–30% on the BLP537 after replacement

This is a voltage cliff problem, not a capacity problem. When the U705W modem transmits or the screen brightness peaks, current draw spikes sharply. A new cell with an uncalibrated fuel gauge IC can report 25% remaining while actual cell voltage drops below 3.4V under that load spike. The phone's protection circuit reads the real voltage — not the displayed percentage — and shuts down to protect the cell. One full discharge-charge cycle recalibrates the coulomb counter and closes the gap between displayed and actual state of charge.

Phone warm near the battery compartment on first charge after swap

A new Li-Polymer cell has higher internal impedance than a worn cell that has been through hundreds of cycles. On the first charge, the Oppo charge IC pushes current into a higher-resistance cell, which converts more energy to heat than usual. This is normal and tapers off after two to three cycles as the cell's impedance settles. If the device stays warm beyond the third full charge, check that the back cover is seated correctly — trapped air between the cell and cover slows heat dissipation and can sustain elevated temperatures unnecessarily.