This is a handy universal battery mount for your Oculus Quest!
It will fit any battery up to 1" thick and includes a rubber shim to accommodate thinner batteries. It's unique U design allows the mount to slightly squeeze any battery for a super-secure hold. It uses velcro to securely attach to the quest head strap and will fit the stock strap or HTC Vive Deluxe Audio Strap.
Originally designed for use with the Ravpower 10,000mAh 29W PD battery (https://amzn.to/3bmH1sO) and the 20,000mAh 60W PD battery (https://amzn.to/3bkiUv9). These are fantastic batteries and fit like a glove in the mount. I also wanted to be able to use my Anker 13000mAh Powercore battery and other batteries I have and found with the use of a little SBR (rubber) strip the way the mount pinches the battery it held every battery I have perfectly. I have to say it's kinda brilliant and works really well. It will also hold the Ravpower filehub plus to provide power AND stream videos wirelessly from an SD card.
The mount includes all the velcro seen attached and the rubber for use with multiple batteries. This isn't the cheapest battery mount available, but it's the most diverse I've seen and takes some time for me to print and then assemble (it' uses 4 velcro straps that are permanently attached as well as 4 velcro strips that need to be glued into place).