Doro 5822 Replacement Battery 3.7V 700mAh Li-ion

Doro 614 / 615 / 680 / 681 Series — 3.7V Li-ion Replacement Battery (5822 / DBB-1000C)

This is a 3.7V 700mAh Li-ion cell replacement for the Doro 614, 615, 680, and 681 mobile phones, along with six additional compatible models. It matches OEM part numbers 5822, DBB-1000C, and XD1105007060. At 40.00 × 40.50 × 6.00mm, it seats directly in the original battery bay without modification.

• Cross-model fit — 614 through 681 series: These Doro handsets share the same battery footprint, connector pinout, and 3.7V nominal voltage rail. The BMS communication protocol is identical across the range, so one cell covers the full group without firmware conflicts.
• Bench tested on actual hardware: We ran the cell through a full charge-discharge cycle on a 614 unit. The BMS accepted charge immediately, voltage held at 3.7V nominal under load, and no thermal events occurred during the test.
• Fuel gauge recalibration on first cycle: After installing this cell, run one complete discharge down to auto-shutdown, then charge uninterrupted to 100%. This gives the fuel gauge IC a clean reference curve for the new cell before the phone starts tracking percentage against it.

Sudden shutdown at 20–30% on the Doro 614 after a cell swap

This is a voltage cliff failure. The fuel gauge IC still holds calibration data from the old, degraded cell and cuts power before the new cell is genuinely depleted. Under modem activity or screen-on load, current draw spikes briefly, the uncalibrated gauge interprets the voltage dip as empty, and the phone shuts down. One full discharge-charge cycle resets the coulomb counter reference and the shutdowns stop.

Doro 614 showing wrong battery percentage after replacement

The phone's fuel gauge IC was calibrated against the discharge curve of the original cell. A new cell has a different internal resistance profile, so the percentage reading drifts — often reading 50% while actual charge is much higher or lower. This is not a fault in the replacement cell. Discharge the phone fully until it powers off on its own, then charge it to 100% without interruption. After that single cycle, the IC recalibrates and percentage accuracy returns.