Dry cell vs. wet cell auto batteries?

Are dry cell batteries much better than wet cell batteries? Are the worth $50 - $60 more than a wet cell?

An AGM or absorbed glass mat battery is not dry, it just doesn't dribble liquid electrolyte if ruptured .
Excellent in aviation and marine as they won't leak electrolyte if ruptured in a crash or due to vibration.
An AGM battery will fail before a flooded cell battery in high temperature applications or if over charged. They will vent fumes if over charged.
Longest lasting battery if abused is a low maintenance flooded battery that allows topping up the electrolyte.
As for service life? I salvaged a five year old AGM battery from a UPS system where two of four batteries had failed. That battery lasted another 11 years in the old JD 70gas .
Batteries, you can get anything from a dud to a Methuselah battery from the same production batch of identical batteries.

"Batteries, you can get anything from a dud to a Methuselah battery from the same production batch of identical batteries."

You got that right, I bought a new diesel pick up in 2001 and about a year into it I had one of the batteries go bad. My mechanic told me it wasn"t a great idea to mix old and new so I had them put both in and took the good one to the farm and put it in my 40s vintage Jeager compressor. Granted it"s a 1000 CCA battery on a flat head Chrysler 6 with a 6 volt starter but it sits for months on end with out being started and often times isn"t run but long enough to pump up the tank so I can air up a tire but it is still hanging in there after 12 years.

i put 3 gel filled batteries from a ups system in a 36 volt ez go golf cart. still going strong when i sold it 3 years later.

The company I used to work for would ship equipment with 12V auto batteries overseas. Often they would sit for over a year before being started. We were always replacing the batteries under warrenty.

We switched to AGM batteries and it seemed to fix the problem. Who knew that regular automotive batteries would die from just sitting in the heat?

Cliff(VA)

Battery in my Oliver was made in 96. I got it in a junk car in 2000.

Dick, not sure what you mean by "dry" cells. I do telephone systems for a living, and depending upon the application, there are three types of cells...wet cell, gell cell, valve regulated. Wet cells are what they are, we all know what they are, and pound for pound, they are unequalled in "proven" reliability. Problem is in a building, floor loading. Wet cells weigh the most, and by the time you tie a bunch of them together to come up with -48 VDC with enough to run several hundred amps continuous for hours, that's a lot of weight, floor loading per square foot. Thats a real important consideration if they aren't on the ground floor. Communications wet cells are said to last 20 years if you don't over do the deep cycle dissipations. Then we get to the worst of them all, gell filled cells like someone else mentioned, are used in UPSs because with inverters constantly running, wet cells would be heated and cooked to death. Gell cells are supposed to have a life of 10 years if setting in a open rack, not being heated in an enclosed compartment like a UPS, and if you get 4 years out of them, you will be very very lucky, and that has been proven so many times that the manufacturers of them won't even try to argue it. The third type is the valve regulated that used to be made by a company named GNB (Great Northern Battery) that has since been purchased by Exide. They are a pretty neat battery, or cell. The insides are fiberglass impregnated by some kind of paste, dipped in electrolyte to be absobed, and then encased in grey steel with valves at the top to blow off gasses if something goes wrong, or overheats, which I have never seen happen. The nice thing about them, is that they are lighter than wet cells for floor loading, which can be an important factor, can't be spilled like wet cells so don't have the EPA worries, last the better part of 20 years like the wet cell, and cost less. Valve regulated cells are supposed to be mounted on their sides for the electrolyte to be absorbed properly, but are often installed standing up because installers thing the valves at the top should face up so as not to leak, which they don't do, and then cause the weight of the electrolyte to work downward, leaving the top of the jars/cells to go dry, ruining them because the electrolyte can only wick its way up about 3/4's of the way. Funny thing is that they come mounted on two steel I-beams that greatly reduces the support to the face area of the I-beams, but incredible increase the floor loading for the area of the two I-beams to support all of the weight. If they aren't going on the ground floor, and they are stacked, take them off of the I-beams to spread the weight out to at least the area of the jarscells, or make sure that the floor can support all of that weight so they don't fall through on some guy sitting at his desk below you, and they guy below him, and the lady below...

I am by far no battery expert, but have learned a little about them, enough to know that batteries truly are a science for people much better than me. Pound for pound though...wet cell are still the best, but in an EPA kind of world...

Good luck.

Mark
Exide/GNB Absolyte Valve Regulated

AGM- absorbed glass mat = Valve Regated