After I posted that reply I thought of a dozen ways I could have said it better. Basically the calcium-type batteries have a characteristic that is an advantage in the rare event your system is over-charging slightly. They will have less tendency to boil the water out of the electrolyte. When your charging system is working properly, there is no need for the maintenance free battery, but there's nothing wrong with having one.
When GM came out with their "Freedom" batteries in the '70s, they were sealed so you couldn't add water. Many people thought that was because you would never have to. In reality, they did that to prevent people from contaminating the electrolyte by using a battery hydrometer to measure the state of charge on a regular battery, then sticking the tube into a maintenance free battery. Something about the electrolyte was different and they didn't want the two to mix.
As for the guy who recommended driving without the battery, you are absolutely correct about destroying computers and doing other damage. I have an entire section on my web site about what can happen and why. I'm a pretty meek fellow but if any salesman ever suggested that to me, I would definitely explain why that is asking for trouble, and if he acted like I was nuts, I'd visit the shop owner to share my concerns. It really is that big of a deal.
Wednesday, July 11th, 2012 AT 6:27 AM