Back at the dawn of the electric car era, when cars like the Nissan LEAF, BMW i3, and Tesla Model S were just starting to get noticed, a lot of people thought battery swapping instead of battery charging might be the way to go. The logic was sound. If you could swap out a discharged battery and replace it with a fully charged one in a few minutes, that would be better than hanging out at a service area on the interstate for an hour or so, waiting for fresh electrons to insinuate themselves into your battery pack, wouldn’t it?
Tesla explored battery swapping briefly, then decided it did not make economic sense and dropped the whole idea after building one facility in Silicon Valley. Now, the idea is back. A patent application dated September 14 describes a system that would raise a vehicle in the air with one set of hydraulic lifts while another inboard lift would drop the battery pack and replace it with a fully charged unit. Here is what the patent abstract says: