I can foresee an MagSafe Apple Battery pack that when attached can be charged via this feature thru the iPhones Lightning adapter. It will also be able to charge when attached to the MagSafe charger.
I just bought this case over the weekend. Love it. It’s a little bulky but it works better than other battery cases I’ve tried. Even though this case doesn’t say it, it DOES work without any problems with an IPhone X WITH updated IO!! my batteries life is down to 87%.