About this replacement
LeTV Le Pro 3 / X720 — 3.85V Li-Polymer Replacement Battery (LTF23A)
This is a 3950mAh Li-Polymer battery at 3.85V, replacing OEM part LTF23A in the LeTV Le Pro 3 and X720 smartphones. It restores power to the display, processor, modem, and all onboard functions. Dimensions are 82.30 × 67.50 × 3.80 mm — match these against the original cell before installing.
- Le Pro 3 and X720 platform fit: Both models share the same battery bay geometry, connector pinout, and BMS handshake protocol. The LTF23A cell interfaces directly with the onboard fuel gauge IC and charge controller without adapter modification.
- Bench tested on actual hardware: We cycled this cell through charge and discharge on the Le Pro 3 platform. The BMS accepted the cell on first contact, thermistor communication registered correctly, and the charge IC stepped through CC/CV phases without fault flags.
- First-cycle fuel gauge recalibration: After fitting this cell, disable fast charging and run one complete discharge down to automatic shutoff, then charge to 100% on standard current. This gives the coulomb counter a full reference curve against the new cell before fast-charge current is applied to an uncalibrated gauge.
Sudden shutdown at 20–30% on the Le Pro 3 after a cell swap
A fresh Li-Polymer cell has a slightly different discharge voltage curve than the aged cell the fuel gauge IC was trained on. At high load — mobile data, screen at full brightness, or active GPS — the modem and display draw enough current to cause a rapid voltage drop that crosses the BMS undervoltage cutoff before the reported percentage reaches zero. The phone shuts down even though the gauge still shows charge remaining. One full discharge-charge cycle without fast charging lets the coulomb counter relearn the curve and close that gap.
Phone warm near the battery during the first charge after replacement
A new cell typically has higher internal impedance than a broken-in one. During the constant-current phase of the first charge, that impedance converts more energy into heat than it will after a few cycles. This is normal on the first one or two charges and does not indicate a fault. If the phone stays warm beyond the third full charge cycle, check that the back cover is seated flat — any gap traps heat against the cell. Surface temperature above 40°C at the back panel warrants investigation.