[cm048]

I use Eltek Multicharger 1500, Upto 100A/12V current.

Though on the expensive side ~800 EUR. It is one of the suggested power supply by BMW.
The important feature is soft start supply mode. It measures the actual voltage level of the vehicle at the connection point, starting power supply mode at the measured voltage level, then slowly increase the voltage to the target level, this voltage increase will take some seconds to reach target voltage.
I am quite happy with the softstart as it reduce the surge which dangerous to both electronic and car battery.

It is also suggest within BMW ISTA/P manual to use soft start mode for Multicharger 1500.