About this replacement
HTC M8 / One Max Series — 3.8V Li-Polymer Replacement Battery (B0P6B100)
This 3.8V, 2600mAh Li-Polymer cell replaces the original B0P6B100 battery in the HTC M8, M8x, M8 Ace, One Max, and over 25 additional HTC variants. It shares the same connector, dimensions (92.30 × 62.00 × 3.20mm), and voltage rail as the factory cell. Swap it in when the original no longer holds a usable charge through a normal day.
- M8 and One Max platform fit: These models share a common 3.8V Li-Polymer architecture, the same physical form factor, and the same BMS handshake with HTC's charge IC — which is why one cell covers the full lineup without pin remapping or adapter modifications.
- Bench tested on actual hardware: We cycled this cell through charge and discharge on an M8 unit. The BMS accepted the full 2600mAh charge without triggering a fault, and the charge IC stepped through trickle, CC, and CV phases cleanly at each transition voltage.
- Fuel gauge recalibration on first use: On first use after installation, disable fast charging and run one complete discharge down to auto-shutoff, then charge uninterrupted to 100%. This gives the fuel gauge IC a clean reference cycle against the new cell's discharge curve before high-current charging pushes current into an uncalibrated state.
Sudden shutdown at 20–30% on the replacement cell
This is a voltage cliff issue, not a capacity defect. Under heavy load — active LTE, screen at full brightness, or a GPU-intensive app — the cell voltage drops faster than the fuel gauge IC expects based on its stored discharge curve. When voltage hits the hardware cutoff threshold (around 3.2–3.3V), the phone shuts down even though the percentage counter still reads 20–30%. One full discharge-to-shutoff and uninterrupted recharge cycle resets the coulomb counter and maps the new cell's actual voltage-to-capacity curve. After that cycle, the reported percentage tracks real capacity accurately.
Phone warm near the battery during the first few charges
A new Li-Polymer cell has slightly higher internal impedance than a cell that has been through 50 or more cycles. The charge IC compensates by pushing a bit more voltage across that impedance during the constant-current phase, which generates mild heat at the battery location. This is normal and reduces after the first three to five charge cycles as impedance drops. If the phone is hot to the touch — not just warm — or the charge IC cuts off early, check that nothing is covering the rear of the phone during charging, since the M8's metal unibody needs airflow to dissipate heat from the charge circuit.