I am using the Tronsmart Presto battery The Wirecutter recently picked, and it charges my 5x rapidly.

https://www.amazon.com/Tronsmart-10400mAh-External-Portable-Technology/dp/B01KNJQZ4W

It's awesome. Quick Charge 3.0, UCB typeC. Doesn't have pass through but I believe that can harm the banks life if it does.