Low voltage? Battery light? Noise? Odor?
Always diagnose first. Prove that it failed first.
Get a free comprehensive battery, charging & starting system test at your friendly, neighborhood auto parts store.
I replace my battery every 4 years without fail. The batteries nowadays do not fail like back in the day. Hard cranking was the usual sign.
An alternator should usually set off the battery warning light on the dash. This happened to my 2013 200 a while back.
If you had the testing done by Auto Zone then the diag is probably right.
We tested the validity of Auto Store's ethics. We put a new battery in a car, took it to Advance, and they said it needed replaced, AutoZone did it too. They want to sell a battery, and they make a decision on how you look and present yourself to con you into one or not. I have pretended hundreds of times that I don't know anything about cars, show up lookin' a little ragged, and you should hear the lies they tell. That's why I order my parts from eBay, I will not buy parts from liars. At least with eBay, if they lie? More times than not, they will refund your money and let you keep the item. You have to be careful when dealing with auto parts stores. If they think you're dumb, they'll sell you everything they can.
My son had issues with a Jeep. He knows nothing about cars. He had a misfire, which it needed a coil. That was ALL it needed. They gave him an estimate, for $800 some dollars for things he didn't even know existed... He signed off on it, because he had no idea what all that meant; and when I saw it, I was like, YOU GOT ROBBED... They knew he knew nothing about cars, and stuck it to him... He was charged for cleaning the engine, the intake, chaging ALL the spark plugs, ALL coil packs PLURAL, when it needed one. They saw him coming a mile away, so, he will never EVER go back to a dealer. There was nothing wrong with that Jeep except the coil pack it needed, and they raked him over the coals... This is why they get a bad rap, and they continue to do it...