Editing Psion netBook Battery Service (section)

=== 1. Check the cells before you fit them ===

'''Confirm every new cell sits at the same voltage''' before connecting them in series. The original rebuilder measured 3.78 V on each.<ref name="libatt" /> Cells at different states of charge will be forced into balance through whatever connects them, which at the currents involved is not a gentle process.

Buy cells you can trust. The 18650 market is full of relabelled and overstated cells; [[Battery Refurbishment]] covers how to tell.