HTC U Play B2PZM100 Replacement Battery 3.85V 2400mAh

HTC U Play — 3.85V Li-Polymer Replacement Battery (B2PZM100)

This is a 3.85V, 2400mAh Li-Polymer replacement battery for the HTC U Play smartphone, including the TD-LTE, TD-LTE Dual SIM, and Alpine variants. It matches OEM part numbers B2PZM100 and 35H00270-00M. When the original cell can no longer hold a usable charge, this replacement restores full electrical capacity to the device.

• U Play variant compatibility: The standard U Play, TD-LTE, TD-LTE Dual SIM, and Alpine all share the same battery bay geometry, connector pinout, and BMS handshake protocol — one cell fits every variant without modification.
• Bench tested on actual hardware: We ran this cell through a full charge-discharge cycle on U Play hardware. The BMS accepted the new cell without throwing a battery authentication error, and charge current stepped correctly through trickle, CC, and CV phases.
• Fuel gauge recalibration on first use: On first use after installation, disable fast charging and complete one full discharge-charge cycle at standard current. This lets the fuel gauge IC map the new cell's discharge curve before high-current charging is applied to an uncalibrated cell.

Sudden shutdown at 20–30% on the U Play after a cell swap

This is a voltage cliff issue, not a defective cell. A new Li-Polymer cell has a steeper voltage drop in the lower state-of-charge range than the aged cell the fuel gauge IC was calibrated to. When the modem or display pulls a high-current burst, the cell's terminal voltage drops below the BMS cutoff threshold before the OS percentage reaches zero. One complete discharge-charge cycle at standard current recalibrates the coulomb counter. After that cycle, shutdowns at 20–30% stop.

USB fast charge not activating on the first cycle after replacement

HTC's charge IC performs a handshake with the BMS before allowing elevated charge current. On the very first cycle with a new cell, the BMS may respond conservatively and the phone defaults to standard 5V charging. This is normal behaviour — not a fault. Complete one full standard-current charge cycle first. On the second charge cycle, fast charge protocol negotiation completes correctly and high-current charging resumes at the expected rate.