About this replacement
Labnet P3600L Series — 3.7V Li-ion Replacement Battery (LN P3600L-BAT-1)
This is a 3.7V, 800mAh Li-ion cell for Labnet single and multichannel electronic pipettes in the P3600L series. It powers the internal motor and control board that drives automated liquid dispensing. The OEM part number is LN P3600L-BAT-1.
- P3600L series compatibility: Labnet single and multichannel P3600L pipettes share the same 3.7V battery rail, connector pinout, and BMS handshake protocol — this cell fits both configurations without modification.
- Bench tested on actual hardware: We cycled this cell through charge and discharge on P3600L hardware. The BMS accepted the cell, completed its initialisation handshake, and held voltage within the expected operating window across the dispense cycle.
- Post-swap power-on sequence: After installing this cell, let the pipette complete its full power-on self-test without interruption. The BMS runs a chemistry verification at startup — cutting power during this sequence can trigger a persistent battery fault that won't clear until the next complete reboot.
Why the P3600L reports a battery fault after a confirmed full charge
The P3600L BMS stores a capacity baseline from the previous cell. When a new cell is installed, the BMS compares measured internal resistance against that stored profile. A fresh Li-ion cell has slightly different impedance characteristics than a worn one, and the BMS can flag this mismatch as a fault even though the cell is fully charged. Running one complete charge-discharge cycle allows the BMS to overwrite the old profile with the new cell's data. After that cycle, the fault clears and the device operates normally.
Charge indicator stuck below 100% on first charge after swap
On the first charge after a battery swap, the P3600L charge IC applies a conservative current limit while it measures the new cell's response. This causes the indicator to stall — typically between 85% and 95% — before completing. The cell is not defective. Allow the charge cycle to run to termination without unplugging; the IC will step up current once it has mapped the cell's charge acceptance curve. On the second charge, the indicator should reach 100% at the expected rate.