My father always used to say, "buy the most cold cranking amps that will fit under the hood. There's no such thing as too much battery."

Then I read in Consumer Reports a few months ago in their battery comparo that buying too much battery can be a waste of money (matter of opinion, if you ask me) and that too big of a battery for your car can SHORTEN battery life. What are they talking about? Wouldn't it be the other way around? A larger battery should last longer than a smaller one, shouldn't it? Or would that be because a stock alternator might not be able to keep up with a bigger battery?
Thanks

 

Well, if you could physically fit a larger battery into your car, that's one thing.

But what Consumer Reports is saying, basically, is that to raise the CCA rating of a battery, without making it larger...compromisies have to be made.

Consumer Reports says that in high-CCA batteries, the plates must be mounted closer together, so that more of them will fit into the case. I'm no battery engineer, but they say that doing this might shorten the life of the battery.

Just remember, in physics...there was that famous guy who said "There's no such thing as a free lunch." For example....To make your car faster, it's going to get poorer fuel mileage. To make your car ride more softly, it's going to handle worse. You have to pick the compromise that's best for you.

Those Consumer Reports ratings can be somewhat useful, but you'll probably find that you'll only be able to get a good price on just a few batteries.

And if you know how to install and replace a battery yourself, and if you remember to get it tested a couple of times a year, reliability and long life are less of a concern than performance.

When I need a battery, I always get the Durlast Gold at AutoZone. It's a little expensive ($70), but has an 8-year pro-rated warranty, with a 3-year free replacement period.