In Mongolia, the voltage is 220V/50Hz, it's the same as in Europe but different from the Canadian and American ones (120V/60Hz). The Mongolian plugs are different from the English, the American, or the Canadian ones, so think of taking an adapter.
During your stays in the steppe, it will be very difficult to find electricity. But if you sleep in a yurts camp, it will be possible to charge the batteries of your electronic material. It will also be possible to charge the batteries on the vehicle's cigar lighter. Think of taking an adapter for that. During the self-sufficient treks, there won't be electricity at all and cars won't be there with you, so you will have to take a solar charger or a spare of batteries.