Sup guys. Just going to trade some information here.
First of all, just about any battery life display widget will inadvertently drain battery life. That's a give. The percentage will probably be small, but if anyone has true statistics I'd appreciate it.
SysTray Monitor is nice, I used it for awhile and only had one problem with it. If you turn on the CPU taskbar widget you'll notice that it's constantly using 5%+/- of your CPU. This may just be CPU widget relevant but I'm not sure.
Last but not least, I use
OS Monitor.
While it doesn't have a tray battery icon it does have a CPU, but if you're extra nerdy it has wayyy more information to display than SysTray.
It does the same 5% CPU bull though, so be weary.