Really useful to have this reminder/insight - thank you!
I am to try sort better charging for my ONE UP in my campervan. I guess what you are saying is that PD chargers should have a good 20V option, 2.25A or better? (Because 15V has little headroom to step down to 13V - I am no engineer so expect I am thoroughly abusing correct terminology, sorry!)
And equally I should ensure any charger I buy for my campervan has proper step-up design to provide a robust 20V output from 12V input?