ZTE X876 Li-ion Replacement Battery 3.7V 1400mAh

ZTE X876 / U500 Series — 3.7V Li-ion Replacement Battery (Li3715T42P3h654353)

This is a 3.7V, 1400mAh Li-ion cell built to the OEM part number Li3715T42P3h654353. It fits the ZTE X876, X70, X60, and U500, along with five additional ZTE models sharing the same footprint and connector. If your original cell has swollen, stopped holding charge, or the phone shuts down unexpectedly, this is the direct cell swap.

• X876 / U500 platform compatibility: These ZTE models share a common battery bay dimension (64.61 × 53.20 × 5.16mm), connector pin-out, and BMS handshake protocol. The voltage rail is identical across the group, so one cell covers all listed models without modification.
• Bench tested on actual hardware: We cycled this cell through charge and discharge on a ZTE U500 unit. The BMS accepted the charge curve without fault flags, and the protection circuit tripped correctly at both over-voltage and under-voltage thresholds.
• Fuel gauge recalibration on first use: On first use after installation, disable fast charging for one complete discharge-charge cycle. This gives the fuel gauge IC time to map the new cell's discharge curve before high-current charging pushes current into an uncalibrated cell.

Sudden shutdown at 20–30% on the ZTE X876 after a cell swap

This happens because the fuel gauge IC is still using the discharge curve from the old, degraded cell. When load spikes — modem transmission, screen brightness burst, or background sync — the new cell's voltage drops steeply in a region the IC hasn't mapped yet. The phone reads that voltage drop as a critical low-battery event and shuts down, even though remaining capacity exists. Run one full discharge to near-zero and a full uninterrupted charge to 100% to push the coulomb counter through a complete reference cycle. After that cycle, the shutdowns stop.

OS reporting wrong battery percentage after replacement

The fuel gauge IC stores a learned model of the old cell's impedance and capacity fade. A new cell with lower internal resistance produces a different voltage-under-load curve, so the percentage reading drifts — often showing 50% when the cell is nearly full, or jumping several points without any use. This is not a fault with the replacement cell. Discharge the phone until it powers off automatically, then charge to 100% in one session without interruption. The IC overwrites its reference model after this cycle and percentage reporting stabilises.