Duracell group 31 AGM batteries installed

[btwlgw]

It's a pretty easy job. I was inspired to do it after seeing that it was nearly impossible to check the water levels in the factory SLA batteries without removing them.

I'll give some tips which are probably common sense but which helped me installing the Duracell batteries into my 3011DS.

The opening (which is lined with a rubber gasket) is smaller than the interior space. I didn't have to remove the rubber.

Make sure you take photos or a video of the factory installation before you start. That way you will have no questions once everything goes back together.

Turn off the battery master switch and remove the old batteries. Make sure you know the orientation of the batteries before you start dropping them in... save yourself some aggravation: positive terminals go to the left. Put the first battery in and slide it all the way left. This will give you room to drop in the second battery straight down on the right. You'll need to finagle the cables out of the way as you situate the batteries. I also had removed the wooden spacers that were attached to the interior bottom of the compartment since I wasn't sure if they would interfere with the larger batteries.

I put a some Corrosion-X on the connections and put some pool noodle foam material around the compartment to take up any slack and prevent shifting while underway. There isn't a lot of extra space to take up, actually.

[CHICKDOE]

2 12 volt batteries in parallel. it looks like the red terminals are postive. black negative. there appear to be two positive cables (excluding the jumpers) connected the positive terminals of each battery. this will work. but shouldn't the black cable connected to the positive terminal of the right battery actually be connected to the positive terminal of the left battery?

[btwlgw]

No. I went back and checked my original video. The positive cable that is covered by the black wire loom goes to the right battery.

Originally Posted by CHICKDOE

but shouldn't the black cable connected to the positive terminal of the right battery actually be connected to the positive terminal of the left battery?

[btwlgw]

By the way, if you haven't heard of it, check it out online. It's used in the military and aviation industries. Wonderful for electrical connections and preventing rust & corrosion on many different surfaces.

[babock]

Originally Posted by btwlgw

By the way, if you haven't heard of it, check it out online. It's used in the military and aviation industries. Wonderful for electrical connections and preventing rust & corrosion on many different surfaces.

Shouldn't need it on an AGM battery. I have AGM batteries on a boat. Not a bit of corrosion and this is with a boat used in salt water.

[cboss]

Originally Posted by babock

Shouldn't need it on an AGM battery. I have AGM batteries on a boat. Not a bit of corrosion and this is with a boat used in salt water.

Agree. I've used our two AGMs in parallel for four years with no corrosion or any other problems. I keep them on a "smart charger" and not on the camper circuit, except when towing.

[BuickGS]

I noticed the fancy dancy non-factory rope carry handle on the new left battery. Just wondering if there is a story behind that... like "I was carrying my new battery over to my RV when the cheap plastic carry handle broke and the battery fell on my foot... ouch"

[Larry-NC]

Originally Posted by CHICKDOE

2 12 volt batteries in parallel. it looks like the red terminals are postive. black negative. there appear to be two positive cables (excluding the jumpers) connected the positive terminals of each battery. this will work. but shouldn't the black cable connected to the positive terminal of the right battery actually be connected to the positive terminal of the left battery?

If both positive terminals are connected together, it doesn't matter which one gets the extra cable. It's electrically the same.

[dave961]

Your enclosure is nice. I had to bolt a box to the front rack for my AGM 31's.

[btwlgw]

Apparently the newer ones come with rope handles. The other one is older that I had on standby in my ham shack.

Originally Posted by BuickGS

I noticed the fancy dancy non-factory rope carry handle on the new left battery. Just wondering if there is a story behind that... like "I was carrying my new battery over to my RV when the cheap plastic carry handle broke and the battery fell on my foot... ouch"

[CHICKDOE]

Originally Posted by Larry-NC

If both positive terminals are connected together, it doesn't matter which one gets the extra cable. It's electrically the same.

there have been hundreds, if not thousands, of posts about how to balance the load across two 12 volt batteries. to do this move the positive cable from the right battery to the left battery so that both positive cables are attached to the positive terminal on the left battery. the negative cable is attached to the negative terminal on the right battery.

if this is not a concern then just ignore the comment.

[BehindBars]

Originally Posted by CHICKDOE

2 12 volt batteries in parallel. it looks like the red terminals are postive. black negative. there appear to be two positive cables (excluding the jumpers) connected the positive terminals of each battery. this will work. but shouldn't the black cable connected to the positive terminal of the right battery actually be connected to the positive terminal of the left battery?

Best to have the positives connected as they are. Otherwise you’d have three ring lugs stacked on one positive post, and one ring on the other. Two rings on each post is what I would chose.

Electrically, either way would work.

[btwlgw]

I just wired it like the factory had it

Originally Posted by BehindBars

Best to have the positives connected as they are. Otherwise you’d have three ring lugs stacked on one positive post, and one ring on the other. Two rings on each post is what I would chose.

Electrically, either way would work.

[babock]

Out of curiosity, what is the 12V lead at the middle? If it's low current not really a big concern for load balancing.

[TBDub]

Since this thread was about Duracell Group 31 AGM batteries, thought this might be a good place to ask my question. I plan to put a Duracell Ultra Platinum AGM Group 31M Deep Cycle (SLI31DTMAGMDC) in my Mini Lite. All three stores in my area have them on back order. One of the dealers wants to sell me their Ultra Platinum Dual Purpose Heavy Duty Group 31 (SLI31AGM). He says the only difference is the single 3/8th" threaded terminal. He says there is no difference with an AGM unlike the Lead Acid. I think there must be some difference between the two. I'm thinking about waiting for the DC. Any thoughts?

[babock]

Originally Posted by TBDub

Since this thread was about Duracell Group 31 AGM batteries, thought this might be a good place to ask my question. I plan to put a Duracell Ultra Platinum AGM Group 31M Deep Cycle (SLI31DTMAGMDC) in my Mini Lite. All three stores in my area have them on back order. One of the dealers wants to sell me their Ultra Platinum Dual Purpose Heavy Duty Group 31 (SLI31AGM). He says the only difference is the single 3/8th" threaded terminal. He says there is no difference with an AGM unlike the Lead Acid. I think there must be some difference between the two. I'm thinking about waiting for the DC. Any thoughts?

They are pretty much the same. Been awhile since I looked at them but the specs are nearly identical.


There will be people that will state that since the AGM has cold cranking spec, they aren't true deep discharge. They are incorrect. Even the AGMs that Trojan sells have a CCA spec in their 12V batteries.


BTW, I bought those same AGM batteries for my boat at Sam's.

[CHICKDOE]

no way to tell without looking at the spec for each. with all the marketing strategies in place it truly might just be the same battery with a different terminal targeted to a different market. perhaps even a different price. one can only guess until you look at the specs.

[TBDub]

Chickdoe, here are the specs. There's a difference in AmpHours and cranking power. Not much else.

Specification
The Deep Cycle RV/Marine
Item Number:*SLI31DTMAGMDC
Brand:*Duracell Ultra
Voltage:*12
Format:*BCI Group 31M
Lead Acid Type:*Deep Cycle, Dual Purpose (Starting/Cycling), Starting
Capacity:*105AH
Cold Cranking Amps:*800
Battery Type:*Premium
Capacity 20hr:*105AH
Chemistry:*Lead Acid
Cranking Amps:*1000
Lead Acid Design:*AGM
Made in the USA:*True
Maintenance Free:*Yes
Marine Cranking Amps:*1000
Product Category:*Marine/RV
Product Sub Category:*Basic AGM
Terminal Type:*DT, SAE/M8 Stud, SAE/M8 Threaded Post, WNT
Usage:*RV, Sump Pump
Warranty:*30 Month Free Replacement
Weight:*67.35 lbs
Length:*12.9375 in
Width:*6.75 in
Height:*9.375 in

The Heavy Duty with single 3/8th threaded posts
Item Number:*SLI31AGM
Brand:*Duracell Ultra
Voltage:*12
Format:*BCI Group 31
Lead Acid Type:*Dual Purpose (Starting/Cycling), Starting
Capacity:*100AH
Cold Cranking Amps:*925
Battery Type:*Premium
Capacity 20hr:*100AH
Chemistry:*Lead Acid
Lead Acid Design:*AGM
Made in the USA:*True
Maintenance Free:*Yes
Product Category:*Truck; HD Equip
Product Sub Category:*Basic AGM
Terminal Type: M6 Threaded Post
Warranty:*48 Month Free Replacement
Weight:*67 lbs
Length:*13 in
Width:*6.75 in
Height:*9.5 in

[CHICKDOE]

wow, they are pretty much the same. the difference i see is in the warranty period.

have fun deciding. is there a difference in price?

[Larry-NC]

Originally Posted by CHICKDOE

wow, they are pretty much the same. the difference i see is in the warranty period.

have fun deciding. is there a difference in price?

You missed the BIG difference. The first one is a deep cycle battery ("DC" in the part number, "deep cycle" in the description). The second one is not.

The first one can be discharged much further than the second one.

That makes a HUGE difference for boondocking RVers and the boating equivalent.