fourpointzero
TJ Addict
Like most topics today.Jesus…. Hot button topic
It's quite amusing how 'serious' we can take the topics. First world problems, you could say. Heck, this is similar the, "tire carrier or no tire carrier?" post.
Are Diehard batteries any good?
- Thread starter thekidwithquestions
- Start date
It's quite amusing how 'serious' we can take the topics. First world problems, you could say. Heck, this is similar the, "tire carrier or no tire carrier?" post.
Mostly "hot button" topics happen because someone will come along with a black and white viewpoint and say my thing is best and all others (suck, are a waste of money, are ugly, etc). That causes an uproar because real life is very rarely black and white. I ran a flooded lead acid starting battery until it died (about 4 years) and replaced it with an AGM with dual Terminals.
For @thekidwithquestions...figure out what you need to do with the battery. Do you have a winch? Do you have a big stereo? Are you going to be using a lot of power off the battery? That should be how you make your decision. Starting batteries are designed to give a whole bunch of power very quickly. They do NOT like to be discharged though...They will provide power to start, then they want to be charged right away. Deep cycle batteries can't supply as much Instant power (Cranking Amps) but they can be drawn down to an 80% (full discharge for a battery is 80%) charge level, again and again and again. You have to watch the cranking amps though, if you want to try and use a Deep Cycle (also called Marine) battery. The AGMs being discussed are kinda in-between. That is why they are so popular with Jeepers. They have a pretty heavy hit (lots of cranking amps) AND they can be discharged. They are more expensive though. If you're going to be running a winch, compressor, big stereo, etc...it pays to have the AGM though. The fact that they don't have any Liquid (AGM-Absorbed Glass Mat) in them to spill is a big bonus too.
For @thekidwithquestions...figure out what you need to do with the battery. Do you have a winch? Do you have a big stereo? Are you going to be using a lot of power off the battery? That should be how you make your decision. Starting batteries are designed to give a whole bunch of power very quickly. They do NOT like to be discharged though...They will provide power to start, then they want to be charged right away. Deep cycle batteries can't supply as much Instant power (Cranking Amps) but they can be drawn down to an 80% (full discharge for a battery is 80%) charge level, again and again and again. You have to watch the cranking amps though, if you want to try and use a Deep Cycle (also called Marine) battery. The AGMs being discussed are kinda in-between. That is why they are so popular with Jeepers. They have a pretty heavy hit (lots of cranking amps) AND they can be discharged. They are more expensive though. If you're going to be running a winch, compressor, big stereo, etc...it pays to have the AGM though. The fact that they don't have any Liquid (AGM-Absorbed Glass Mat) in them to spill is a big bonus too.
Or put another way, those of you who think you know what you are talking about really tend to annoy those of us who do know what we are talking about and that's when the crap starts.
Paul Land
TJ Enthusiast
Once again, these were originally meant for non-serviceable and hard to get to area's. The first commercial-civilian use was power back-up on transmission towers in remote locations with extreme weather conditions regular lead/acid would boil out if not maintained. It is still just a Lead Acid Battery. Here's a history lesson for those who want to know. AGM (Absorbed Glass Mat) sealed battery technology was originally invented in 1980, and developed and introduced in 1985 for military aircraft where power, weight, safety, and reliability were paramount considerations. The Concorde AGM batteries are VRSLAB (Valve Regulated Sealed Lead-Acid Battery), sometimes referred to as VRLA (Valve Regulated Lead-Acid). Several manufacturers now produce AGM batteries, but Concorde was the first to develop the technology for commercial non-military use.
I am aware of the history just as I am aware of the history of the Jeep we all drive. The TJ iteration has about as much in common with the original as today's AGM versions do to the original intended solution.
Yes, they are in fact lead acid batteries in the tightest definition but the only aspect that really matters for what we need is the fact that you can run one laying on its side and you can't do that with a conventional lead acid battery because all the fucking electrolyte will run out.
That and the history is meaningless since all we need is something that doesn't let acid spill, doesn't weep acid to corrode the crap out of the terminals and doesn't cost a fortune.
There are three major automotive starting flooded battery manufacturers in the United States. There are four absorbed glass-mat (AGM) starting battery manufacturers and there are four flooded deep cycle battery/major deep cycle battery manufacturers in the United States. There are 6 lead mines in the US, so really not much differences in manufacturers, just what is put in what case. But I guess I am an idiot..
Now I see that I should have jumped on this with both feet and much harder. No, all lead acid batteries are NOT the same at all, not even a tiny bit. Using your dumbass definition, that means we should be able use a gel cell deep cycle marine battery for SLI use and that is simply not the case. While they do have a higher depth of discharge than a flooded cell, they don't accept high current charge rates very well and that tends to be their undoing along with their limited ability to deliver high current.
The vast majority of SLI compatible AGM batteries even with higher depth of discharge and number of cycles have very good current supply ability even though they qualify as a "deep cycle" battery. They also have the potential for a much higher charge capacity that will ruin a conventional lead acid. If you want to figure that out the easy way, simply put one as the other half of the pair in a diesel pick up that runs dual batteries from the factory. The low resistance and ability to handle a higher inrush current will boil the acid out of the conventional in very short order. That isn't speculation or supposition, but real world actual I have seen it with my own two eyes. And, even with the acid completely boiled out of the conventional, the single AGM kept starting the rig.
You're not an idiot but to assume that a factory puts the exact same number of plates with the same purity level stacked to the same rate in every single battery and the only thing that changes is the color of the case is short sighted at best.
To assume that the lead purity level is identical because it come out of the same lead mine is short sighted at best. One of the key factors in making the AGM stuff work is the high purity lead sheet. Also the reason that the Optima is built with rolled cells instead of stacked plates. When they first started building the Optima, they didn't have the machines that could handle the delicate pure lead in individual sheets so they rolled it.
I run an Autozone 34AGM battery, I got a good deal on it and I used to shop at Autozone allot. It was a bit under $200. My next battery will probably be the O'Reilly AGM, I think the one @tworley mentioned. It's still $200 and I shop there more often now. I'd buy the cheapest AGM you can find from a nation wide auto parts store you like. Batteries fail and just getting a ride to a local store and swapping it out is so much better than dealing with some fancy online battery that needs to be delivered, especially if you are on a trip somewhere wheeling.
deadbeat son
TJ Addict
Both of the batteries you mention are relabeled Deka Intimidators from EastPenn. The same as the Duracell that Sam's Club sells for $169. Why spend more? (Other than you hate Wal-Mart / Sam's...which I can't fault anyone for.)
By the way, the Duracell Group 34M (marine) AGM is only $119. https://www.samsclub.com/p/duracell...p-size-sl34magm/prod3590225?xid=plp_product_1
Paul Land
TJ Enthusiast
Paul Land
TJ Enthusiast
Your talking about plate thickness for starting vs deep cycling. The chemistry is identical for ION Exchange in any Lead Acid battery which has 2 forms of Lead 1-Lead plate and 2- Lead sponge and sulfuric acid is the ION transfer medium.
deadbeat son
TJ Addict
That’s the battery I’m running, primarily for the extra terminals. So far, so good.
It’s worth noting, the marine batteries all seem to have a shorter warranty period than the automotive only batteries.
I wonder why the CCA values are over 200 amps lower on those even though they are slightly larger (at least the few I checked)?
Because they're not optimized for high current draw, they're optimized for deep discharge.