Community Forums

toddb · 10-21-2020, 03:29 PM

It’s that time again…. Time to replace house batteries. Current batteries are NAPA 9831DT (Qty 6, Group 31 AGM). These were installed about 5 years ago replacing the original NAPA batteries that came with the coach. Coach is 2011 Itasca Ellipse (same as Tour). Batteries are below a hatch in the basement storage (which is why they are AGM so no hassle with water/electrolyte level).

Found this out the hard way 2 weeks ago. Woke up in the middle of the night with everything off. Inverter had reached its low battery cutoff voltage and shut down. Dry camping worked fine in Feb but a recent trip dry camping the batteries would charge, go to Float stage, voltages looked fine, Onan Command battery state looked good but batteries would drain in less than 1 hour once the genset was turned off. Ended up running the genset all night. Day time was fine with 750W of solar running the house and charging batteries, but as soon as that big yellow thing got low in the sky, we needed the genset.

So….my options are to once again replace the current NAPA batteries with the same or look for alternatives. I don’t want to change or upgrade my inverter, looking for thoughts/advice, folks who have been there done that replacing a similar bank of house batteries.

Thx in advance.

PS I intend to buy the batteries on our next trip to Oregon (along with tires for the toad) this fall to avoid sales tax!

sibe · 10-21-2020, 03:40 PM

trojan agm 31 seem popular and wok well..

i use deka because factory is close to me and have had good luck

creativepart · 10-21-2020, 03:59 PM

Winnebago has used the NAPA Commercial AGMs for a long time. My 2017 came with four of them. They are three years old and doing fine... so far. I expect to get five years out of them, like you. NAPA lists them for $369 ea. Which is too high if you ask me.

DEKA/Eastern Penn makes the NAPA battery and sell their Intimidater AGM for $339 each.

https://www.amazon.com/East-Penn-8A3.../dp/B07G9J9364

If you're staying AGM there are plenty of Group 31, 100aH 12v AGMs available. But I'd consider getting them online rather than hoping to find the brand you want at a retail outlet in Oregon.

Renogy AGMs meet the specs you're looking for and are a lot cheaper than the NAPA's - about $170 a battery cheaper!

https://www.amazon.com/Renogy-Batter.../dp/B075RFXHYK

Walmart sells the VMax as a "replacement" for the NAPA battery for a good price as well. But when I looked they were sold out.

https://www.walmart.com/ip/VMAX-MR13...-AGM/414504349

Interstate has a good price on 110 aH 12v AGM deep cycles on Amazon:

https://www.amazon.com/dp/B00YB26RYG?pd_rd_i=B00YB26RYG

Good luck finding pricing like this at a retail shop in Oregon - no sales tax or not.

Battleborn Lithium Iron Phosphate are a logical replacement choice - you could probably do better than fine with 4-Lithiums to replace the 6-AGMs since you can use more of the power without harming the battery. It would cost nearly $4000 but have a 10-year warranty and service life.

Winemaker2 · 10-21-2020, 04:35 PM

Sams Club East Penn GP 31 AGM only about $180.
Why would you pay over $300?

Phil G. · 10-21-2020, 05:05 PM

Quote:

Originally Posted by toddb

It’s that time again…. Time to replace house batteries. Current batteries are NAPA 9831DT (Qty 6, Group 31 AGM). These were installed about 5 years ago replacing the original NAPA batteries that came with the coach. Coach is 2011 Itasca Ellipse (same as Tour). Batteries are below a hatch in the basement storage (which is why they are AGM so no hassle with water/electrolyte level).

Found this out the hard way 2 weeks ago. Woke up in the middle of the night with everything off. Inverter had reached its low battery cutoff voltage and shut down. Dry camping worked fine in Feb but a recent trip dry camping the batteries would charge, go to Float stage, voltages looked fine, Onan Command battery state looked good but batteries would drain in less than 1 hour once the genset was turned off. Ended up running the genset all night. Day time was fine with 750W of solar running the house and charging batteries, but as soon as that big yellow thing got low in the sky, we needed the genset.

So….my options are to once again replace the current NAPA batteries with the same or look for alternatives. I don’t want to change or upgrade my inverter, looking for thoughts/advice, folks who have been there done that replacing a similar bank of house batteries.

Thx in advance.

PS I intend to buy the batteries on our next trip to Oregon (along with tires for the toad) this fall to avoid sales tax!

Just as a heads-up ... if you do go with Group 31 12V AGM batteries, and since "Group 31" means a specific physical size ... you might want to at least use an AGM Group 31 model with as large an amp hour capacity as possible.

I have seen Group 31 AGM batteries with 100 AH capacity, 115 AH capacity, and 125 AH capacity. My preference is to pack as many amp hours as possible into a given battery size.

RedLamar · 10-21-2020, 05:12 PM

Tomorrow when it is warmer I will replace the 3+ year old Everstart Group Deep Cycle Group 29 (current Walmart price $89.97) with Duracell # 347736, Group 31 AGM batteries (current Sams Club price $179.74).

For my application Winnebago specifies 665 Cold Cranking Amps. The Everstart comes closest at 662 CCA and NAPA's 8231 has 650 but the Duracell has the most I have found at 800. The Duracell has good reviews plus a 1.5 year replacement warranty. While the current Everstart batteries have not failed yet in midwest fall temperatures, in early January when we pull out for Arizona I just don't need any unnecessary drama.

My biggest concern is that while the Group 31 replacement batteries should fit in the tray OK, they are taller than the Group 29 batteries that are there and would leave very little room for the cables when I am moving the battery tray in and out. Guess I'll find out soon enough how much of a problem this will be.

Good luck and be sure to post how things work out.

Safe travels.

chuckftboy · 10-21-2020, 05:57 PM

If you like the NAPA batteries, 5 years isn't too bad, NAPA has 20% off with a AAA membership number. Not too bad on batteries that retail at $291 each.

Ohiomike · 10-21-2020, 06:00 PM

Quote:

Originally Posted by Winemaker2

Sams Club East Penn GP 31 AGM only about $180.
Why would you pay over $300?

This is true. I’ll bet the Napa batteries are East Penn also but more expensive. I’d go to sams club.

toddb · 10-21-2020, 06:52 PM

Thanks for the input. In doing some research the NAPA batteries ($291ea) look identical to the Duracell Ultra Platinum AGM. Identical case, physical size, weight and capacity with CCA/AH. Duracell is $239ea at our local Batteries Plus.

Agree on packing in most AH I can. Would love to go Battle Born with LiFe but haven't won the lottery yet.

Appreciate the input, will keep looking. Have 1 month before next trip to decide on Oregon purchase, online or local. Toad tires at least I'll get up there.

Mr_D · 10-21-2020, 07:08 PM

If you're replacing house batteries why are you even looking at something with a CCA (Cold Cranking Amps)? You want a battery with no CCA rating and a high 20 amp hr rating. A starting battery needs a high CCA to serve the high draw of a starter. The combination batteries are a compromise and not the best for either purpose. They are OK in situations where one sey of batteries starts the engine and runs a few lights like a boat does.

Phil G. · 10-21-2020, 07:11 PM

Quote:

Originally Posted by toddb

Thanks for the input. In doing some research the NAPA batteries ($291ea) look identical to the Duracell Ultra Platinum AGM. Identical case, physical size, weight and capacity with CCA/AH. Duracell is $239ea at our local Batteries Plus.

Agree on packing in most AH I can. Would love to go Battle Born with LiFe but haven't won the lottery yet.

Appreciate the input, will keep looking. Have 1 month before next trip to decide on Oregon purchase, online or local. Toad tires at least I'll get up there.

The 12V Group 31 deep cycle AGM batteries in our motorhome are 115AH each, and cost about $305 each.

Before I bought them, I almost instead bought Lifeline 12V Group 31 deep cycle AGM batteries at 125AH capacity each. The Lifelines cost about $350 each at the time.

SavnTheWales · 10-21-2020, 11:25 PM

If your going to spend $300 a piece for (2) 12v 100ah batteries, you might as well just get (1) BattleBorn lithium. You will have the same usable amp hrs and about the same cost.

Winemaker2 · 10-22-2020, 05:08 AM

Quote:

Originally Posted by Mr_D

If you're replacing house batteries why are you even looking at something with a CCA (Cold Cranking Amps)? You want a battery with no CCA rating and a high 20 amp hr rating. A starting battery needs a high CCA to serve the high draw of a starter. The combination batteries are a compromise and not the best for either purpose. They are OK in situations where one sey of batteries starts the engine and runs a few lights like a boat does.

Thats true for FLA but not AGM. If you check the Duracell specs they also list AH at 20A rate. The plate design doesn't vary the way FLA does so a GP31 AGM has similar deep cycle performance as the GC2s

twinboat · 10-22-2020, 05:32 AM

Quote:

Originally Posted by SavnTheWales

If your going to spend $300 a piece for (2) 12v 100ah batteries, you might as well just get (1) BattleBorn lithium. You will have the same usable amp hrs and about the same cost.

Your comparison is not really true.

If I have 200 AH of AGM I can safely use about 160 AH.
Do it every time and I shorten my battery life in half, but once in a while is no big deal. Beats waking up with the heat off.

With a 100 AH lithium, it will shut down at 90 AH of use. No wiggle room with the BMS.
Now I have nothing, no lights, no water pump, not even generator starting power.

Your going to need 2, 100AH lithiums.