ZTE U200 Li3708T42P3h453756 Replacement Battery 3.7V 830mAh

ZTE U200 / U201 / U210 — 3.7V Li-ion Replacement Battery (Li3708T42P3h453756)

This is a 3.7V, 830mAh Li-ion battery for the ZTE U200 series smartphones. It replaces OEM part numbers Li3708T42P3h453756, Li3709T42P3h453756, and Li3707T42P3h443747. The cell fits U200, U201, U210, and U218 handsets sharing the same battery bay and connector spec.

• U200 series compatibility: These four models share the same 3.7V single-cell rail, identical connector pinout, and BMS handshake protocol — which is why one cell services the entire group without modification.
• Bench tested on actual hardware: We cycled this cell on a U200 handset and confirmed the BMS accepted the new cell, charge current ramped correctly through CC/CV stages, and the protection circuit tripped cleanly at the low-voltage cutoff threshold.
• Fuel gauge recalibration on first use: After installing this cell, run one full discharge to auto-off followed by a complete uninterrupted charge before enabling any fast-charge mode — this lets the phone's fuel gauge IC map the new cell's discharge curve before high-current charging begins.

Why the U200 reports wrong battery percentage after a cell swap

The U200 uses a coulomb counter that was calibrated against the original cell's impedance and discharge curve. A new cell has different internal resistance characteristics, so the counter's stored reference points are no longer accurate. The phone may report 40% and shut down, or sit at 1% for an extended period before jumping. One full discharge-charge cycle forces the fuel gauge IC to relearn the new cell's actual capacity endpoints and corrects the reported percentage.

Sudden shutdown at 20–30% on the replacement cell

This is a voltage cliff failure, not a capacity problem. Under modem or screen load the cell voltage sags below the BMS cutoff threshold while the fuel gauge still reads 20–30% remaining. It happens most often in the first few cycles before the fuel gauge IC recalibrates. Run two complete discharge-charge cycles and confirm the shutdowns stop; if the phone still cuts out under load, check that resting cell voltage reads above 3.7V after a full charge.