The only proprietary battery thing I’ve come across using APC for decades was a connector that combined two standard batteries. It was attached to them and bound them together with stickers and connected to the terminals of each with normal terminal connectors. I just bought 2 standard replacement batteries and put the adapter on them. It all fit right back in and ran like new.
https://community.cloudflare.com/t/setting-up-minecraft-srv-records-on-cloudflare-connect-via-your-domain-name/636757
It takes special setting in addition to your normal domain DNS settings.