Trouble cranking

On two occasions this week after driving & parking the car,when I tried to start up again I turned the ignition key on & nothing happened.

The dash board dials swung wildly when I tried to crank. Both times I waited a few minutes , turned the key again & it cranked right over. It was not a weak crank like the battery was dead.Could it be a bad cell in the battery ?

This is a duplicate post. I responded to this version: http://community.cartalk.com/posts/list/2184398.page

and then flagged this one. Hopefully it will go away.