Well it is a die hard so maybe replaced in 08 or 09??
But honestly from that pic there is some corrosion happening on the battery connection.
I used a copper pipe wire brush to get inside of the connector and didn't really have any corrosion what so ever.
My new optima is 800 CCA, the old one was to.
When I did the HIDs a couple years ago, my positive connection was funked and I drained the battery. I did bring it back to life with a battery tender but was always paranoid.
Just saying , that positive could be a problem. clean it GOOD and a washer under the nut. then get some of this to coat all the connections.