About this replacement
HTC U11 Life — 3.85V Li-Polymer Replacement Battery (B2Q3F100)
This is a 3.85V, 2500mAh Li-Polymer cell for the HTC U11 Life, U11 Life Global LTE-A, and Ocean Life smartphones. It replaces OEM part numbers B2Q3F100 and 35H00274-0M1. Fit the replacement when the original cell has degraded past the point where it can hold a usable charge through a normal day of calls and screen-on time.
- U11 Life and Ocean Life platform compatibility: These models share the same battery bay dimensions, connector pinout, and BMS handshake protocol. The 66.30 × 60.58 × 4.00mm cell fits all three variants without modification to the battery compartment or flex cable routing.
- Bench tested on actual hardware: We ran this cell through charge and discharge cycles on a U11 Life unit. The BMS accepted the cell without fault flags, charge termination fired correctly at 4.35V, and low-voltage cutoff engaged at the expected threshold without voltage sag triggering a hard shutdown.
- Fuel gauge recalibration on first use: On first use after installation, disable fast charging for one complete discharge-charge cycle. This lets the fuel gauge IC recalibrate its coulomb counter against the new cell's discharge curve before high-current charging pushes current into an uncalibrated cell — preventing false percentage readings early on.
Sudden shutdown at 20–30% on the U11 Life after a cell swap
A new Li-Polymer cell has a slightly different discharge curve than the aged cell the fuel gauge IC was calibrated to. When the modem fires a high-current burst — during a call handoff or LTE band switch — the cell voltage dips sharply. The fuel gauge reads that dip as a critically low state and the phone cuts power before the reported percentage reaches zero. One full discharge-charge cycle without fast charging resets the coulomb counter and aligns the IC to the new cell's actual curve.
Phone warm near the battery during the first few charging sessions
A fresh Li-Polymer cell typically has higher internal impedance than a cell that has completed several charge cycles. The charge IC compensates by pushing slightly more voltage to maintain the target current, which generates more heat at the cell surface. This is normal for the first three to five charge cycles and settles as the cell's impedance drops. If warmth continues beyond that point, check that the USB port and cable are delivering clean 5V — a marginal cable raises charge IC workload further.