AGMLead acid batteries are capable of handling higher heat by design, so that's not a fair comparison.
Your link is broken, so not exactly sure what you are trying to get it. And yes, AGM batteries are popular too, but it still remains that car batteries can handle the heat better and not a valid comparison.
It's actually the other way around. If your battery gets extremely hot, there could be an issue with the battery. Batteries may also get warm to hot if you are using a lot of resources while charging.If the batteries in a phone can't take getting HOT while charging.
There is a problem with them.