Quite a bit of interesting technical discussion here, though these guys
talk as though nothing like this has ever been invented previously!

https://www.busnews.com.au/bus-reviews/1902/video-review-yutong-e12-electric-bus?fbclid=IwAR2B-_3ZvbTBsgfaheUT6mXRD11cGDr0FOYzjQoyIX-kCDCJt1iEGhey74w

Tony P