I just read an article describing the multiple problems which occur when you're trying to increase the electric current transmitted through an cable to charge the battery of an electric car. These include the weight of the cable itself (increased diameter) as well as the need of an active cooling system (dissipated heat, temperature sensors). Nowadays values about 50-135 kW are the maximum - some car manufacturers try to increase this to 350 kW to decrease charging times.
Why do they decide to use only one charging cable instead of using several existing cables in parallel? (This parallel charging probably already happens inside the battery - each cell itself won't cope with drastically increased charging currents.)