About this replacement
Rainin EDP3 / EDP3 Plus — 3.7V Li-ion Replacement Battery (6107-040)
This is a 3.7V 800mAh Li-ion replacement for the Rainin EDP3 and EDP3 Plus electronic pipettes. It matches OEM part number 6107-040 and fits the motorized aspiration and dispensing assembly directly. Voltage and physical dimensions — 48.50 × 30.00 × 8.00mm — match the original cell.
- EDP3 and EDP3 Plus compatibility: Both pipette variants run the same 3.7V power rail and share the same battery bay geometry and BMS connector pinout, which is why a single cell covers both. Substituting the wrong voltage disrupts the motor-control board's regulated supply.
- Bench tested on actual hardware: We cycled this cell through the EDP3's full charge-discharge sequence and confirmed the BMS accepted the cell without fault codes. Charge termination and low-voltage cutoff both triggered at expected thresholds.
- Post-swap power-on sequence: After installing this battery, allow the EDP3 to complete its full power-on self-test without interrupting or powering off mid-cycle. The device runs BMS verification at startup — cutting power during this sequence logs a false battery fault that persists until a clean reboot.
Why the EDP3 alarms low battery immediately after a confirmed full charge
The EDP3's BMS stores a capacity model calibrated to the original cell's charge curve. A new cell with a slightly different internal resistance profile can read as below threshold on the first cycle even when fully charged. This is not a cell defect — it is the BMS applying its stored model against unfamiliar impedance data. Run one complete charge-discharge cycle and the BMS recalibrates its reference, clearing the alarm. After that first cycle, the low-battery alarm should trigger only at the correct depletion point.
Charge indicator stuck below 100% on the first charge after swap
The EDP3's charge IC applies a conservative current limit when it cannot confirm the cell's history, which extends the final constant-voltage phase and stalls the display below 100% for longer than expected. The cell is still accepting charge — the indicator is waiting for the current to taper to the termination threshold. Do not interrupt the charge or assume the battery is faulty. Leave the device on charge until the indicator completes or the charger disengages automatically, then confirm the resting voltage reads 4.1–4.2V before clinical use.