batteries

upnover

Grumpy, decrepit Old Man
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Mar 20, 2005
Location
Morganton NC
At some point in time, if you ever try and trail ride a difficult trail, you're probably going to have to winch. "IF" you find yourself in a really difficult trail, if could very possibly become a "winch fest" In other words, a LOT of winching. Now my question is simple. When I had my first AGM battery, it was an optima red top, I have also had yellow tops, an deep cycle blue tops, at the present, I have two Duracell AGM batteries in my Jeep. What I have noticed is that the more I winch, the lower my voltage goes. And from my experience, AGM batteries do not recharge (no mater how big of an amp alternator) very fast. In the past, as in many years ago, I have had issues with lead acid batteries leaking out when I rolled my Jeep or even laid it on it's side, and that was the draw for me to use AGM batteries. Now, most batteries can come in a "sealed" version. I know that if a battery charges up quick, it's gonna discharge quick too. But like this past weekend, where I seemed to find every rock that I either high centered on, or, my cut down 14 bolt(13 bolt) seemed to find every notch that captured my Jeep an held it hostage, as in could not go forward or backwards. So much winching, and while since I run 2 batteries, I didn't feel as though I was starving my winch for power, I did notice a drop in voltage. I do have electric cooling fans for both my engine and my trans, so once they past 160 degrees, they stayed at 180* except for hard pulls. They won't urn off until 160*, at night, I had anywhere from 8-10 LED lights running, and also ad in my fuel pump and of course my engine. I only run a 60amp alternator. I have known for a long time that AGM batteries just do not charge fast, so never went with a higher amp alternator. But I have been re-thinking this because while it may not re-charge my batteries any faster, the extra amperage would help in running fans, fuel pump and lights. So, My question is

What benefit is there in running agm batteries. vs sealed lead acid batteries
 
The alternator is doing the work with the engine running. Batteries are backup power. I'd upgrade to a decent sized alternator long before buying 2 new batteries.
Also, are your batteries in the back, or under the hood? I can't remember. If in the back, cabling is a big issue as well.
 
It sounds like your weak point is your alternator. In a hard pull, winches will draw 200-500 amps. Lets assume yours is in the middle at about 300 amps. So if you have a 200 amp alternator, it is able to support 200 amps of the load, and the batteries are making up the other 100 amps. It's not quite that simple, but will work fine for this illustration. With your 60 amp alternator, the batteries are carrying 240 amps of the load, which drains them down faster, and then the lower voltage actually requires more amps to do the same work. Whereas the alternator is pumping constantly at a higher voltage, the batteries immediately start dropping. I'm sure @Ron can get deeper into the tech if you want, but that's the general premise.
 
The alternator is doing the work with the engine running. Batteries are backup power. I'd upgrade to a decent sized alternator long before buying 2 new batteries.
Also, are your batteries in the back, or under the hood? I can't remember. If in the back, cabling is a big issue as well.
I agree, I would benefit from a higher amp alternator, That I am sure of. My batteries are under the hood, close to the engine
It sounds like your weak point is your alternator. In a hard pull, winches will draw 200-500 amps. Lets assume yours is in the middle at about 300 amps. So if you have a 200 amp alternator, it is able to support 200 amps of the load, and the batteries are making up the other 100 amps. It's not quite that simple, but will work fine for this illustration. With your 60 amp alternator, the batteries are carrying 240 amps of the load, which drains them down faster, and then the lower voltage actually requires more amps to do the same work. Whereas the alternator is pumping constantly at a higher voltage, the batteries immediately start dropping. I'm sure @Ron can get deeper into the tech if you want, but that's the general premise.
Again, I agree, a larger amp alternator would serve a lot of my issues.
But, that wasn't really my question, The question being, what is the benefit of running AGM over a sealed lead acid battery or in my case batteries (I run two AGM's at the moment) In a situation like I was in this past weekend, Lots of run time(12 hours) and the AGM's do not charge back very fast. Where as, If I were runnung sealed Lead acid batteries, they would charge back faster. But to answer, No, I am not thinking of going out and buying two more batteries, at least not until the two AGM batteries I have bite the dust.
 
I thought one of the benefits from AGM batteries was longevity. I know my original Optima red top that I bought in 2003 lasted longer than any lead acid battery I have ever owned.
 
Again, I agree, a larger amp alternator would serve a lot of my issues.
Running a CS-144 from some GM-based mimi-van (Silhouette/TransVan?) that absolutely ROCKS! A bit larger dia/depth than 10S/12S, but not that hard to package...
I thought one of the benefits from AGM batteries was longevity. I know my original Optima red top that I bought in 2003 lasted longer than any lead acid battery I have ever owned.
Yeap... the end of an era when batteries weren't total shit/meant to die exactly 3 days AFTER the warranty runs out. My first redtop lasted for years... numerous "totally deads" from parasitic drain + numerous winch/light fests and kept coming back, until it didn't.
 
I thought one of the benefits from AGM batteries was longevity. I know my original Optima red top that I bought in 2003 lasted longer than any lead acid battery I have ever owned.
Yeap... the end of an era when batteries weren't total shit/meant to die exactly 3 days AFTER the warranty runs out. My first redtop lasted for years... numerous "totally deads" from parasitic drain + numerous winch/light fests and kept coming back, until it didn't.
Yep, my 2001 Red Top was still holding about 11.8 volts in 2017 when I replaced it with another Red Top. Threw the new POS Red Top away before the Uwharrie G2G because it wouldn't hold a charge. What a demise of a fine product.

So @upnover whatever you do, don't get an Optima. They are junk these days. I've had better service from an Autocraft battery.
 
And from my experience, AGM batteries do not recharge (no mater how big of an amp alternator) very fast.
Your alternator has no idea whether it's charging an AGM battery or a flooded-cell battery. The variable is the size of the batteries themselves. The AGM batteries are likely higher capacity than a flooded-cell battery would be, and you have two of them. If you had a flooded-cell battery in the same conditions, the likelihood is that it would be dead.

Regardless, 60A is a very small alternator. I'd start there for any possible upgrades. There should be 100A-130A parts house alternator swaps available without going to an exotic aftermarket solution.
 
Again, I agree, a larger amp alternator would serve a lot of my issues.
But, that wasn't really my question, The question being, what is the benefit of running AGM over a sealed lead acid battery or in my case batteries (I run two AGM's at the moment) In a situation like I was in this past weekend, Lots of run time(12 hours) and the AGM's do not charge back very fast. Where as, If I were runnung sealed Lead acid batteries, they would charge back faster. But to answer, No, I am not thinking of going out and buying two more batteries, at least not until the two AGM batteries I have bite the dust.
I'm no battery expert, but the charge rate is determined by how much capacity is available to charge, regardless of the type of battery. If you have a 60 amp alternator, and 40 amps are dedicated to lights and gizmos and making the gasoline go boompop, that only leaves 20 amps to charge the batteries, or 10 amps each, which will take several hours to charge. Add in anything that exceeds your 60amps and the batteries are draining again. I promise I'm not trying to beat a dead horse, but the root of your charging and voltage recovery isn't the battery size or type, it's the insufficient recharge capacity. Outside of that, you already know the advantages/disadvantages of SLA vs AGM, so to me it really just comes down to cost difference between the two, and how important sealed/non-spillable is for the application.
 
I'm no battery expert, but the charge rate is determined by how much capacity is available to charge, regardless of the type of battery.
Yup. I think the confusion stems from the manufacturer's recommendations of 0.1 to 0.2C charge rates for AGM batteries vs 0.3C rates (or higher) for wet cell. The thing is, we're not talking about a smart charge controller here, just a (dumb) alternator. It has no idea what sort of battery it's charging or what the charge rate should be. It's just trying to maintain a certain voltage level based on whatever draws are currently on the system.
 
OK, just got back to my desk top(I don't do internet on my phone) Been up at my shop cleaning the Jeep, as it will likely be in storage for 6-8 months. As if 2020 wasn't bad enough with five surgeries/procedures, I am getting ready to have the much sought after colonoscope and after that, back surgery. I have to have some vertebra fused and some rods installed. I am actually looking forward to this since I have been dealing with back pain for literally decades. It wasn't so bad at first, but it has got worse gradually. Anyway, back to my initial question, (although I appreciate all the comments about my rinkidink alternator), What has been said about that, I agree.
My initial question was... What is the difference between an AGM battery, and a sealed Led, flooded cell battery. There is usually a cost difference, My first red top worked great for years, I think it was year 9 or 10, before it give me issues. Bought another one, and it was junk.When I went to a red top, my whole reason was that it would not spill acid all over under the hood, should I lay the Jeep over, or, roll it. But now, and they have for years, they have the lead acid batteries, so, am I correct in saying they won't spill out should I roll or lay it over? I do not run an isolater, both of my batteries are hooked together. I basically run two batteries because I need two, to use my Ready Welder. The two I have are smaller, not sure of the group number, Brand (and could be made by whoever) is Duracell. I got a deal on them from Sam's Club, Both batteries was something like $180.00 three years ago. And so far, they have not let me down.
It has been mentioned, that the AGM will last longer, that may be the case for some, but, like the red tops becoming Junk, I bought an AGM from Rural King to use on my trailer I guess it didn't like setting unused for long periods, and it died and wouldn't come back after less than 2 years.
It has been discussed also, about the charge rate of the AGM. Yes, a dumb alternator doesn't know what kinda battery it's charging. But, The AGM (in my experience), will only charge as fast as it wants to. I was curious about this, and had heard it from several folks, so, I run my two down to I think it was 10.3 volts. I disconnected them, I put a 10 amp charger on one battery ( oh, and BTW, my meter showed the batteries were both discharged within ,1V) and I put a "smart" AGM charger at 2amps on the other. In 6 hours charging, and they were not fully charged, the batteries were withing .3V of each other, the more charged being the one on the 2amp "smart" charger. Took till the next day, nearly 24 hours later, until the smart charger had it's battery at 14.1V, and the 10am charger had it's battery at 14.0v. The 10 amp was still trying to charge, while the "smart" charger had backed down and was reading 12.8v I think??
In my experience, a lead cell battery can be REALLY dead, and in a few hours you can have it back up to full charge. I see it as the lead cell is more like a sponge, it will soak up a charge really fast. I do know that too many of that kiinda charge can cause damage to that type of battery, On the other hand, the AGM battery doesn't get affected as much. I "think" part of the solution would be to run(if you wanted to get away from AGM) is to use a sealed Deep cycle battery. The plates are thicker in these and do not try and fuse themselves together, like the regular lead acid battery. Anyone have first hand experience with using deep cycle batteries?
 
That's a pretty decent summary. As for the battery test, I'd want to put a clamp meter on each to see how much current was actually being delivered. The AGM has lower internal resistance, so should charge faster and will deal with big loads (like a winch) with less voltage drop than an equivalent flooded cell.

I've never had good luck with a wet cell battery in a wheeling rig. They get the shit shaken out of them and the plates disintegrate and short out.

I bought an AGM from Rural King to use on my trailer I guess it didn't like setting unused for long periods, and it died and wouldn't come back after less than 2 years.

Was there any draw on it when it was sitting? Could have been a dud, but could also have been an issue with a 'dumb' charger.
 
That's a pretty decent summary. As for the battery test, I'd want to put a clamp meter on each to see how much current was actually being delivered. The AGM has lower internal resistance, so should charge faster and will deal with big loads (like a winch) with less voltage drop than an equivalent flooded cell.

I've never had good luck with a wet cell battery in a wheeling rig. They get the shit shaken out of them and the plates disintegrate and short out.



Was there any draw on it when it was sitting? Could have been a dud, but could also have been an issue with a 'dumb' charger.
I used to run a regular battery myself, but, it's been so long ago, I don't remember much about them. Now that's the type of real world experience I value, and put stock into.

The Rural king battery was sitting in a battery box, mounted to my trailer. Winch hooked up, but of course, not running, also, fuel pump hooked to it also, had a switch on the negative side, So, it it hit something, Or something hit it, it would only be another possible ground.
 
I thought one of the benefits from AGM batteries was longevity. I know my original Optima red top that I bought in 2003 lasted longer than any lead acid battery I have ever owned.
I also had a 2004ish red top that went in multiple vehicles and left with my Samurai I sold in 2016. I just put a new one in my tow rig, and I know they're not what they used to be, but it was the only AGM I could get quickly with top and side posts...
 
Winch hooked up, but of course, not running
A little bit of corrosion inside a contactor/solenoid will complete the circuit and put a small draw on the battery. I had a winch that pulled about 0.2A continuous.

Not saying that's your problem, just that you can't assume something's not pulling power just because it's switched off.
 
A little bit of corrosion inside a contactor/solenoid will complete the circuit and put a small draw on the battery. I had a winch that pulled about 0.2A continuous.

Not saying that's your problem, just that you can't assume something's not pulling power just because it's switched off.
Not gonna say thier was or wasn't any corrosion, But I am pretty anal about using die-electric grease on all my 12v connections.
 
Not gonna say thier was or wasn't any corrosion, But I am pretty anal about using die-electric grease on all my 12v connections.
The corrosion I'm talking about would be inside the solenoids themselves.
 
It has been discussed also, about the charge rate of the AGM. Yes, a dumb alternator doesn't know what kinda battery it's charging. But, The AGM (in my experience), will only charge as fast as it wants to. I was curious about this, and had heard it from several folks, so, I run my two down to I think it was 10.3 volts. I disconnected them, I put a 10 amp charger on one battery ( oh, and BTW, my meter showed the batteries were both discharged within ,1V) and I put a "smart" AGM charger at 2amps on the other. In 6 hours charging, and they were not fully charged, the batteries were withing .3V of each other, the more charged being the one on the 2amp "smart" charger. Took till the next day, nearly 24 hours later, until the smart charger had it's battery at 14.1V, and the 10am charger had it's battery at 14.0v. The 10 amp was still trying to charge, while the "smart" charger had backed down and was reading 12.8v I think??

This is a comparison of chargers, not batteries.
Like every body said, install a bigger alternator and you won't recognize your rig.
60amp is ridiculously low, a stock samurai alternator is 55amp.
 
This is a comparison of chargers, not batteries.
Like every body said, install a bigger alternator and you won't recognize your rig.
60amp is ridiculously low, a stock samurai alternator is 55amp.
As I have said in so many words, I realize, YES, I should have a bigger amp alternator. I only give my experience of the discharging batteries was to say, "It got me to thinking"
So far I have received only two(I think) two responses to my question.
@shawn said his experience was that the shaking around pretty much caused premature failure, of the lead acid batteries.
and @drkelly saying that he always thought one benefit of the AGM type batteries was longevity.
This thread is NOT about how to fix my issue
It's about what are the benefits of an AGM battery vs a sealed lead acid battery.
like, are the cases thicker/stronger on one verses the other?
and so on.

At the moment, I am NOT in the market for new batteries. Even though I have noticed the discharge under extreme conditions
Just watching my guage got me to thinking.

I do have a one wire160 amp Alternator that I need to have gone through. It's been so long since I used it, I forget all of the details of it's demise. What do do remember is that for what ever the reason I took it off my old Jeep, it got put into a bucket of parts, and forgot about. The bucket was left outside and it rained. Filling the bucket with water and the alternator(the 160 amp one) was left submerged in water for an extended amount of time. There very well may not be anything wrong with it, but in my mind I need to at least have it took apart, cleaned and checked out.
 
That looks like a good link:

 
The two I have are smaller, not sure of the group number, Brand (and could be made by whoever) is Duracell. I got a deal on them from Sam's Club, Both batteries was something like $180.00 three years ago. And so far, they have not let me down.

The Rural king battery was sitting in a battery box, mounted to my trailer.
I have the same Duracell (possibly DeepCycle?) from Sam's in my trailer, going on it's 4th year. Honestly, I want to attribute that to the total anal-retentive rewire in 2017, but not sure... all I know is it sits for months at a time, oddly is fully charged after sitting (only charges when connected to truck), BUT I do have disconnects on it so no means for parasitic drain.
 
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