I don't understand your comment. The fee would apply to the patent holder, for retaining the patent. The licensing fees could be whatever the patent holder want

I don't understand your comment. The fee would apply to the patent holder, for retaining the patent. The licensing fees could be whatever the patent holder wants, if they decide to license it. That's no different from today. If the new way of manufacturing battery cells is of no commercial value and that you don't make any money off of it, then what's the point of holding the patent?