No individual cell voltage monitoring. But some original Bosch batteries lack that too. I just took apart a 14.4V 4Ah one and there is none.... three cell pars are at +4.2V... one cell pair is at -2V. RIP. It was used in a DIY application that made extreme deep discharge possible.
Do you make electric to battery adapter for 18V bosch tools so that i can just slot in a socket into the battery slot and the other end to a wall plug. That way i can use bosch battery tools directly from electric 230V in case my battery runs out.
I haven't tried this yet. It should be possible to use an adjustable power supply. It should be noted that the power supply must be large enough, and the discharge current of the 18650 power battery is still quite large.