AGM Batteries In Equipment

[LCA078]

Thank you for both of those post. They are informative and well written. Also good video on the first one.

Thanks- I appreciate the compliment. For my current job position, I had to do a lot of research on batteries in heavy duty equipment and I learned it's not really that complicated once you understand the basics. So hopefully after explaining the basics of what I know, everyone here too can be better informed when they drop their hard earned cash on a new set of batteries. Just paying it forward to the group...

 

[Tyler d4c]

I agree but this is also one of those "Yes, but..." statements.

I started buying lower cca batteries a few years ago too when I was told the same thing. Everything I own is 24v diesel so at least I try to match a high cca battery to my 'larger' engines. For instance, the trucks with a Cummins 8.3L I'll go with two 750-800 cca but for the Cummins NHC-250 (14L), I'll go with a pair of 1000cca for that little bit extra crank. Does it really matter for me in central Texas (today will be a high of 80F)? Probably not but it's what I do.

But after doing a lot of my own research (for my own particular job/career right now), I don't think all manufacturers are really using thicker plates that are truly more mechanically robust for lower cca batteries. I think some are just not using as many plates of the same thickness to achieve the lower cca. Here's why I think it's a mixed bag out there:

At Walmart, you can buy the EverStart Group 65 850 cca and 150 min reserve for $140 or the 650 cca with 140 min reserve for $110. Each weighs 47.4lbs so at least here I believe the plates are thicker for the 650 cca. A reduction of 200 cca but the same weight implies the same amount of lead so the plates are probably thicker by 31% in the 650 cca.

And now look at Catepillar Group 31 batts which I'm sure are very commonly used by everyone here. There are three types: General duty, Heavy Duty, and AGM (see the attached brochure).

For heavy duty, let's compare two similar group 31's with the only difference being cca and reserve. You can see the 1000cca battery is actually a pound lighter than the 825cca even though it has 21% more cranking power. This means the 825cca has less plates and they must be thicker, about 26% thicker than the 1000cca. The rule of 'lower cca = thicker plates' holds true here like the Walmart batteries.

View attachment 355469


But when you look at Cat's General Duty batteries, I think they're trying to hose us. For these the 1000 cca is 58lbs while the 760 cca is 52.5lbs. From my calculations, there really is no thickness change in the plates between the 1000cca vs 760cca. The 760cca is just a weaker battery. Here the rule breaks down.

View attachment 355468

If you want to get into the brute batts, the AGMS, here you can see a much more robust battery. The 800 cca is a full 6lb heavier than the 925 cca and has higher reserve than anything else. So, on the outside, it looks like the AGM is by far a better battery for anyone to stick in their vehicles.

View attachment 355471

But wait, remember the discussion about charging profiles where AGMs need to charge at lower voltage than flooded cells? Even in the Cat brochure it says to charge their AGMs at a lower voltage:
Alternator and charger instructions: for 12-volt AGM Batteries charge to 14.4 volts but no more than 14.6 volts at 68° F (20° C). If you don't, you're just frying your $$$ Cat AGM.

So bottom line: A lower CCA battery that weighs as much or more than a higher CCA batt in the same brand and family probably has thicker plates. If it weighs much less, it's probably just a cheaper battery. And if you toss in an AGM into the system, make sure you're charging it correctly or it may be a waste of effort.

Good information for us not knowing. The 14 year old exides got replaced with Cat battetys. We put cat batterys in everything if they have one that fits. We seem to get the longest life from them.

 

[LCA078]

I think the Cat Heavy Duty's are better built than the General Duty ones. A Cat heavy duty group 65 is 46 pounds while the general duty is 41 pounds so a lot lighter with a lot less lead. But what kinda sucks is the dang Walmart brand group 65 is 47.4 pounds! This is why I have trouble recommending a specific brand anymore...so many variables like anchored bottoms, through cell connections, etc. really come into play.

I've always wanted to cut open a bunch of batteries and make a video of the internals like folks due with oil filters. But man what a messy, nasty thing to cut open batteries!

 

[Welder Dave]

It does depend on brand. I think some better batteries have a thicker case top that would add weight. One of the 8D's I replaced in my track loader was considerably heavier. Even when I exchanged it for a reconditioned battery the guy agreed it was extra heavy and he handled a lot of batteries. Don't know what brand it was but must have been close to 150lbs.
Major pain to take out with the backhoe attached. Had to remove the whole seat and support it bolts too to get it out and didn't have any kind of hoist to lift it. I've since cut slots in the back plate so I can loosen the bolts and slide the back plate up and off.

 

[Simon C]

Cat sells a premium 8D battery that I have bought for Cat3412 generators, and they stopped the starter failures from the heavy current load required to start, about 150 LBS or more than I was willing to lift alone.
Simon C

 

[Coaldust]

Great write up, LCA078. Thanks

 

[Coaldust]

Comical moment last week with some group 31 AGM’s in a new Western Star. We had not officially taken delivery of this unit, yet. But, the shipper had left the ignition key on, in the accessory position and the batt switch on. So, it’s sitting at the Port of Anchorage with frozen batteries, inconveniently blocking operations.

Hey, your truck won’t start. Hey, ain’t my truck. You left the battery switch on. No, we didn’t, the cargo company left the switch on.
Talk to them about it. Come get your truck.

Dude, I can’t get on the Port. My top level security port clearance expired and I’m not sitting through your BS mandatory training BS and background check ever again. Somebody is removing the passenger seat and putting new batteries in this truck and it ain’t me.

But, they showed me. They put some used, cheap group 31 cores in it to get it moved to the terminal. So, I still need to put new batteries in it.

 

[LCA078]

Come get your truck.

Yeah, that'll get 'em jumping. Sometimes folks just have to realize 'oh crap- it really legally is my piece of equipment doing that!'

Speaking of 8Ds, or 4Ds for that matter, any 'modern' piece of equipment still come with them as the standard battery? I know the marine folks still like them because they have massive reserve. But from my measurements, you can squeeze 3 group 24's or 34's in place of an 8d and get way more cca and have equivalent reserve. A couple 24s/34s can replace a 4D with similar results.

Other than some additional cabling, I can't think of a reason to 'fork' around with those big ol' boxes of lead. Or is using an 8D for theft protection? lol!

 

[Truck Shop]

Freightliner Alliance Group 31--950 cca, $91.99, last roughly 3.5 to 4 years being run everyday.
All I care about is it cranks.
*

 

[Simon C]

Freightliner Alliance Group 31--950 cca, $91.99, last roughly 3.5 to 4 years being run everyday.
All I care about is it cranks.
*
View attachment 355607

Absolutely correct, cause once its running it's the alternator that keeps her going until the next start.
Simon C

 

[LCA078]

Freightliner Alliance Group 31--950 cca, $91.99, last roughly 3.5 to 4 years being run everyday.
All I care about is it cranks.

I know I've seen that battery before but I don't remember the Alliance brand. And then I remembered it looks suspiciously like the NAPA Commercial 950cca at twice the price: https://www.napaonline.com/en/p/BAT7236&store=801884

 

[LCA078]

Well, heck. I was trying to find the specs to see if the Alliance or Napa brand was lighter or had less reserve capacity but when I searched on Alliance Group 31 950cca, I saw a dozen different brands with that exact same plastic case. Just a different sticker. I didn't look at specs but clearly it's by the same manufacturer: East Penn.

 

[Truck Shop]

I know I've seen that battery before but I don't remember the Alliance brand.

The real point is the price, it's the best price for 31's in my area, and lasts the same amount
of time in a OTR. Les Schwab is $226 for same. There are Freightliner dealers everywhere
870 plus, I can't see a reason to buy anything else. I've used about eight different brands
all lasting about 3.5 to 4 years. Zero reason to be spending twice the amount plus for same
performance. Batteries are a consumable product in the cost of maintenance, some only
slightly better or worse. Shock/shorted plates is the common killer in OTR. When underneath
doing a service it's customary to reach up and run a hand over each battery looking for a
a warm one or the smell of rotten eggs with one venting. If within 3 years old, replace all.

 

[BC Placer gold]

I just bought 2 group 31's last week for $99 (plus $28 core) from our local International dealer. Replaced two half size batteries from 2017 in our 'new' Hitachi EX100-1

Unusual to have an almost even price match to south of the border. They have them sitting there by the pallet load...good bang for the buck I figure!

 

[LCA078]

The real point is the price, it's the best price for 31's in my area, and lasts the same amount
of time in a OTR

Hmmm.....have I been overpaying? Sure looks like it....

But to be fair, it doesn't have the pop-up handle so the top is a bit different. I'm sure East Penn uses that case for a lot of their Group 31s. But until you cut it open and look inside, it's hard to say what it really is...

 

[Truck Shop]

The handle is just a spec thing, handling selling point. I'm sure there are some internal
differences but most of a batteries longevity goes to what it's installed in, is it secure,
how many times has it been run down, has the charging system had issues. Years ago
{about 20 now} I had Interstates on hand in the shop, I noticed when the truck showed
up each month to replace there were several in the dead box that had same names.
The delivery guy stated those brands were his best advertisement, {Napa, Les Schwab}
were the main two. He did point out the average person was better off to buy a battery
at Bi Mart for the simple fact they sell fresh batteries, the store turn over meant it hadn't
sat on the shelf a year.

 

[Welder Dave]

The problem with multiple batteries instead of one big one is there are more places for corrosion and bad connections. I think one big battery would be less money as well.