https://www.cnet.com/news/ces-2019-breeze-wants-to-make-it-easy-to-charge-your-phones/

Instead of handing out power banks by hand though, the company has automated the process with a dock that dispenses and charges up these rental battery packs. To unlock one, you just need to scan the QR code on the machine and it automatically allocates a charged battery pack for use.

Payments are done through your credit card, and if you're not old enough to have a credit card, there's also a family account that parents can set up to pay for their kids. The first 30 minutes of charging are free, and the company aims to charge around 40 Singapore cents an hour (about 30 cents), but if you run away with the battery pack, you'll have to cough up $30.