I got an Ohmipax battery and it's been doing a great job: https://www.amazon.com/dp/B01N1909E2?psc=1

I'm sure the Anker is good too, though.

I've had good luck with Ohmipax: https://www.amazon.com/dp/B01N1909E2?psc=1

Using it right now, as a matter of fact.