AGM Batteries

[rinkside7]

We have a 2016 Pinnacle RSQS and plan to install 2 AGM batteries. Husband wants to know if we need to change the Pinnacle charging system to one that will charge the AGM batteries?

[wanderlust]

No need to change the existing system. I'm curious... why are you changing to AGMs?

[Mustang65]

IF you purchase AGM batteries ($$$), I would recommend installing a Digital Voltage Meter, like either of the ones below. They will give you the current status of your battery(s). There are a lot of Digital Voltage Displays available on Amazon.

Do you have a Residential fridge? That is a whole different ballgame regarding the battery.

Don

[mike837go]

Originally Posted by wanderlust

No need to change the existing system. I'm curious... why are you changing to AGMs?

I'll also question the need to spend money when a cheaper product (flooded cell, deep cycle batteries) do a better job and with a modicum of maintenance, give a longer service life.

[troutslayer]

Originally Posted by mike837go

I'll also question the need to spend money when a cheaper product (flooded cell, deep cycle batteries) do a better job and with a modicum of maintenance, give a longer service life.

Mike, could you expound on that? I bought a VMAX TANKS deep cycle AGM battery and, according to literature and reviews, it is supposed to last 8 to 10 years. It is also supposed to be more low-temp tolerant (which is one of the major reasons I bought it) and I never need to add water. I do agree that it is pricier, but not twice the cost of a good flooded cell deep cycle battery. Just curious.

[rinkside7]

Thanks for all the replies..the main reason for the AGM's is that they are low maintenance and long life. Its also very inconvenient to access the batteries and add water. We do alot of dry camping on the beach and use plenty of battery power. We do not have a residential refrigerator....we were instrumental in having Jayco offer the Norcold PolarMax 18.5 two-way in their rigs...we love the fridge.

[TCNashville]

Even though we don't boondock, my next camper battery will be an AGM. I know they cost more but with no maintenance, long life and able to take abuse the extra cost is a trade off. This is the one I was looking at. https://www.samsclub.com/sams/durace...lp:product:1:4

[Mustang65]

Originally Posted by TCNashville

Even though we don't boondock, my next camper battery will be an AGM. I know they cost more but with no maintenance, long life and able to take abuse the extra cost is a trade off. This is the one I was looking at. https://www.samsclub.com/sams/durace...lp:product:1:4

I believe that most AGM battery shoppers are unaware that the AGM batteries follow the life cycle of the Flooded batteries when it comes to the "Number of Cycles" and "Depth of Discharge". So the same 50% rule that Flooded battery owners use is also there for AGM batteries. So the number of cycles is the same for both. Below is Trojans "Cycles/Depth of Charge" chart for their AGM batteries, and Flooded batteries... which are basically the same as all other mfr.

My Registry

Don

[troutslayer]

Originally Posted by Mustang65

I believe that most AGM battery shoppers are unaware that the AGM batteries follow the life cycle of the Flooded batteries when it comes to the "Number of Cycles" and "Depth of Discharge". So the same 50% rule that Flooded battery owners use is also there for AGM batteries. So the number of cycles is the same for both. Below is Trojans "Cycles/Depth of Charge" chart for their AGM batteries, and Flooded batteries... which are basically the same as all other mfr.

My Registry

Don

Yea, I agree. On another thought, when I started looking for an AGM battery, I thought they were automatically all deep cycle...WRONG! Big difference between a true deep cycle (flooded or AGM) and other batteries. There is a huge difference in the discharge rate.

[Mustang65]

Originally Posted by troutslayer

Mike, could you expound on that? I bought a VMAX TANKS deep cycle AGM battery and, according to literature and reviews, it is supposed to last 8 to 10 years.

Another point that most mfr do not clarify is that when they say the batteries will last 5,8,10 years they are probably correct. The batteries will hold a charge and look good on a Digital Voltage Display. The part that they do not make know is that the original Rated 85Ah battery, is only capable of maybe 40Ah or less after 4+ years. You will notice a definite reduction on how long things will operate on the battery after 4 or 5 years, less if you do not follow the 50% rule (not letting the battery voltage drop below 12.0VDC)

If you want to see an actual test on 4 year old Interstate 85Ah battery check out the test results. Scroll down the post "The Results are in".

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Don

[cariboocreek]

I put a pair of agm's in last summer after one of my stock batteries boiled over. I don't need that mess again at a campsite.

[Mustang65]

Originally Posted by cariboocreek

I put a pair of agm's in last summer after one of my stock batteries boiled over. I don't need that mess again at a campsite.

Were you able to find what caused the original battery to boil? Battery charge controller issue? Bad battery cell?

AGM batteries will also boil and unfortunately if they do boil you have no way to replenish the water which leads to the death of an AGM battery. AGM batteries will expel a gas through the vent (if overcharged) and if not monitored may crack the battery case.

That is why I asked if you were able to find what caused the original flooded battery to boil.

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Don

[cariboocreek]

Originally Posted by Mustang65

Were you able to find what caused the original battery to boil? Battery charge controller issue? Bad battery cell?

AGM batteries will also boil and unfortunately if they do boil you have no way to replenish the water which leads to the death of an AGM battery. AGM batteries will expel a gas through the vent (if overcharged) and if not monitored may crack the battery case.

That is why I asked if you were able to find what caused the original flooded battery to boil.

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Don

Best we can figure is that the dealership overfilled the batteries when they serviced the trailer. They admitted to topping up the batteries. The charging system was checked and works fine and worked the rest of the summer with no issues.

My description of boiling over may be inaccurate as we don't 100% know whether they vented excess water or boiled. Both batteries were involved.

It was a pain at a campsite to slosh the whole compartment with baking soda and try to eliminate further issues.

[gypsmjim]

We have 3 cars, 4 boats, a tractor and a camper. I bought an AGM and was happy with the service and low maintenance so over a 3 year period I switched everything over to AGM.

Then came some failures, dealers not willing to honor warranties and a complete failure that the dealer attributed to a run of bad batteries. Now I'm back to 100% flooded.

No more AGM for me.