Article: These devices are easier to use than a multimeter, though they don't do as much as a multimeter. These testers have a slide that moves back and forth to adjust to different battery sizes. Open the slide and insert a AA, AAA, C, or D battery into the slot with the positive side touching the slide. Then check the display for the volt reading.  To test a 9v, some meters have a separate port to touch the battery against for a reading. Check your meter to see if it has this feature. Some meters can also test lithium ion batteries if they’re shaped like standard alkaline batteries, but not if they’re irregularly shaped.

What is a summary?
Place the battery in a battery tester for a simple reading.