missing battery icon

[carnelian2]

I have a laptop with Linux Mint and a netbook with easy peasy. With Mint I have a battery icon on the desktop bar, but not on the easy peasy netbook. When I go to power options on Mint, I am shown a tab for AC mains and one for battery. On the netbook I have only the AC mains tab. How do I get the battery tab and icon to show. Simple explanation please!