About this replacement
Kyocera DuraXV Extreme / DuraXE Epic — 3.8V Li-ion Replacement Battery (SCP-73LBPS)
This is a 3.8V, 1600mAh Li-ion replacement battery for the Kyocera DuraXV Extreme (E4810) and DuraXE Epic (E4830). It carries OEM part number SCP-73LBPS and fits directly into the battery bay on both handsets. Swap it when the original cell no longer holds a charge or shuts down unexpectedly under load.
- DuraXV Extreme and DuraXE Epic compatibility: Both the E4810 and E4830 share the same battery bay dimensions, connector pinout, and BMS communication protocol — that is why one cell covers both platforms. The fuel gauge IC reads the same data lines on each handset.
- Bench tested on actual hardware: We cycled this cell through full charge and discharge on the E4810. The BMS accepted the charge handshake on the first cycle, voltage held steady at 3.8V nominal, and no thermal cutoff events fired during the test run.
- Fuel gauge recalibration on first use: On first installation, disable fast charging and run one complete discharge-charge cycle at standard rate. This lets the fuel gauge IC map the new cell's discharge curve before high-current charging pushes current into an uncalibrated cell — it prevents erratic percentage readings from the first hour of use.
Sudden shutdown at 20–30% on the DuraXV Extreme after a cell swap
This happens because the fuel gauge IC on the E4810 is still calibrated to the discharge curve of the old, degraded cell. When the modem fires a high-draw burst — a call, a data sync, GPS — the new cell's voltage drops sharply under that load. The phone reads that transient voltage drop as critically low and cuts power, even though the actual state of charge is higher. One full discharge-charge cycle at standard rate resets the coulomb counter and the shutdown threshold moves back to where it should be.
Phone shows 100% immediately after install and drops fast in the first hour
The fuel gauge IC stores the previous cell's capacity baseline in memory. When a new cell goes in with a different impedance profile, the IC reads the open-circuit voltage, assumes a full charge, and reports 100% — but its drain model is wrong. Charge drops fast because the counter is burning through an inaccurate capacity estimate, not because the cell is weak. Discharge the phone fully until it powers off, then charge uninterrupted to 100% at standard rate — the IC writes a new baseline and percentage tracking stabilises from that point.