Powering a LattePanda 3 Delta with a battery

I'm interested in the LattePanda 3 Delta for my latest SBC project. I have done a lot of reading on the various methods of power for the board. One thing that I'm struggling to understand is where to find battery packs with a JST PH2.0 4-pin connector.

I am planning to buy or build a 4S2P li-ion or lipo UPS based on the design of u/Project-SBC in this video. However, I'd like to retain the use of the USB-C port on the Delta. Therefore, it becomes necessary to connect the UPS through the JST connector.

If anyone could point me to resources for how to do this, I'd be thrilled.