Suburban Starting Issues

[va mountain hunter]

I have a 1997 Surburban that is having some strting issues that seem to be heat-related, and might be as simple as a battery.

 

Last summer, the vehicle cut off on me twice. Both times were at red lights in the heat of the summer when the AC was going full-blast and the radio was on. Went through all of the fall and winter and spring with no more problems, but it happened again on a really hot day a few weeks ago. Now it won't start at all most mornings, but after the sun has gone down it will sometimes start as if there's nothing wrong. It turns over and runs for a split second, then dies just as the battery meter seems to surge. I'm going to try a new battery this evening, but I'm wondering if there are other issues that seem more likely that I may want to look into.

 

Any ideas? Thanks in advance.