Asus ZenFone X C11P1322 Replacement Battery 3.8V 2300mAh

Asus ZenFone X / T00D Series — 3.8V Li-Polymer Replacement Battery (C11P1322)

This 3.8V, 2300mAh Li-Polymer cell replaces the factory C11P1322 battery in the Asus ZenFone X, ZenFone S, T00D, and PadFone X. It matches the original connector, physical footprint (92.73 × 39.50 × 4.10mm), and BMS communication protocol. Capacity is sourced from product data at 8.74Wh.

• ZenFone X / T00D platform fit: These models share the same voltage rail, flex connector pinout, and BMS handshake requirement. Swapping a cell with a mismatched BMS profile triggers charge IC rejection — this cell uses the C11P1322 communication spec to avoid that.
• Bench tested on actual hardware: We cycled this cell through charge and discharge on ZenFone X hardware. The BMS accepted the charge IC handshake on the first connection, and the fuel gauge IC tracked state-of-charge without triggering a fault flag.
• Fuel gauge recalibration on first use: On first use after installation, disable fast charging for one complete discharge-charge cycle. The fuel gauge IC was calibrated to the old cell's discharge curve — running one full cycle at standard current lets it recalibrate against the new cell before fast charge pushes higher current into an uncalibrated register.

Sudden shutdown at 20–30% on the ZenFone X after a cell swap

This happens because the fuel gauge IC still holds the discharge curve from the old, degraded cell. When screen brightness peaks or the modem fires up, the new cell's actual voltage under load drops faster than the IC predicts — and the phone cuts power before the displayed percentage reaches zero. It is not a faulty cell. One full discharge-charge cycle at standard current rewrites the coulomb counter baseline. After that cycle, shutdowns at 20–30% stop.

Phone feels warm near the battery during the first few charges

A new Li-Polymer cell arrives with slightly higher internal impedance than a cell that has completed several cycles. The charge IC pushes current into that higher-impedance cell, and the extra resistive heating is normal for the first two to three charges. Temperature should drop to normal levels as impedance settles. If warmth persists past the third charge cycle, check that the flex connector is fully seated — a partial connection forces the charge IC to retry, which increases heat.