If you'd like a power bank with replaceable batteries and don't thoughts sacrificing some power: Get the Panasonic BQ-CC87. Powered by up to four AA or AAA rechargeable batteries, this power bank has an unconventional structure that allows you to reuse it indefinitely—making it more sustainable than most power banks, https://magsafe-power-bank29528.blue-blogs.com/32939069/power-bank-an-overview