Here is one I use.... AUKEY Quick Charge 3.0 Power Bank 20,000mAh. Use this and the original one supplied with my original Vive. No issues with wireless adaptor although a little heavy in your pocket. I;m used to it though. Recommened, although there are many new ones that would be ok I'm sure. Quick recharge 3.0 was the
main reason I got this one and the 20,000mah too.
https://smile.amazon.co.uk/AUKEY-20000mAh-Portable-Charger-Lightning-Black/dp/B01H01C720/ref=sr_1_5?dchild=1&keywords=aukey+20000&qid=1589219054&sr=8-5