Join Date: Apr 2006
Thanked 253 Times in 248 Posts
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Re: Realistic expectations for my house batteries
If you are US born, the helpful folks at Social Security say that since you've made it to age 65 you will very probably live to age 86. So...you know, getting 20 years on the next set might not be such a bad idea. One less heavy thing to move around when you're 86.(VBG)
I'm an AGM fan as well, mainly because I got tired of replacing acid-eaten cloths. Factor in the cloths and maybe some carpet or other fabric, and the AGMs become cheaper than wet lead.
But I think your case of AGM vs wet lead is a bit skewed. You've gotten excellent but exceptional life from your AGMs, indicating a good charging system. Some folks have also reported 8-10 years from Rolls, Surette, and other top quality wet lead batteries. Most folks report half of that, regardless of battery type, so how you are maintaining them is more likely the reason for the great longevity.
And of course being sealed and needing no water is great--except, that gives you no ability to add water if there's been overcharging for any reason. That's a double-edged sword. The distilled water itself is trivial. 94c per gallon at WalMart, $1.50 at any supermarket in the laundry aisle if it isn't with the water products. If you need to top up frequently, that's again just a charging problem, not the battery's fault. (And how many charging systems are temperature compensated, or designed for marine use instead of cars, at all?)
In exchange for that, wet lead will be about 1/3 cheaper than AGM. Ignoring the cost of the inevitable acid eaten clothing.(G) So, not so bad for everyone, just not the right solution for all of us.