IMO, the main issue with this is Batteries are expensive and degrade over time. Which makes it very hard to trust an independent 'gas station' to actually give you the real product and deal with the older battery's correctly and swap in new ones into the mix, and creates huge incentive for people to ‘miss report’ how many times a battery has been charged etc. You would also end up with a 'full tank' lasting a somewhat arbitrary distance depending on how new your replacements where.