I was looking through an ArchLinux thread on URxvt, and I came across a setup at post #184 that I am going crazy looking for.

It looks like there's some kind of battery bar in the PS1, with a bitmap there too. I'm not all that new to Linux, but I can't find anything on how that's done.
It's fine if it's only for a specific shell, I would just like to know more about it.