Run a Optima AGM in Parallel With a Walmart Deep Cycle Battery?

maczilla23

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Can I safely run a Optima AGM in parallel with a Walmart Deep Cycle battery? Or will the batteries kill eachother? I dont want to ruin my optima but I dont really want to buy another :lol:

If its a bad idea ill swallow the bullet and go buy another optima. Thanks!
 

frantically relaxing

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Re: Run a Optima AGM in Parallel With a Walmart Deep Cycle Battery?

Based on my experiences, but I'd buy 2 Walmart batteries before I'd spend a nickel on an AGM...
 

matt167

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Re: Run a Optima AGM in Parallel With a Walmart Deep Cycle Battery?

Were top of the line. There quality has fallen into the dumpster in recent years. Oddessy batteries have a bit more quality, and Sears Diehard Platinum batteries are made by Oddessy for a cheaper price.

Personally, I'm a lead-acid believer. Cheap and reliable. What you want to do should work fine tho
 

ajax5240

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Re: Run a Optima AGM in Parallel With a Walmart Deep Cycle Battery?

Whats wrong with the Optima AGM? I thought Optimas were top of the line!

They are terrific batteries, but in most cases they are way more than you need. The Wal-Mart batteries work great and you can get two of em for less than one optima.

If its for a race truck that sees a ton of vibration, or needs to be mounted on its side due to space limitations, you need an optima. If you are trying to run a trolling motor, the everstart is all the battery you will need. I'd put the optima as your cranking battery and buy another ever start to run with your trolling setup.
 

maczilla23

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Re: Run a Optima AGM in Parallel With a Walmart Deep Cycle Battery?

They are terrific batteries, but in most cases they are way more than you need. The Wal-Mart batteries work great and you can get two of em for less than one optima.

If its for a race truck that sees a ton of vibration, or needs to be mounted on its side due to space limitations, you need an optima. If you are trying to run a trolling motor, the everstart is all the battery you will need. I'd put the optima as your cranking battery and buy another ever start to run with your trolling setup.


So I could just run an everstart in parallel with my optima? Just making sure. Thanks!
 

airdvr1227

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Re: Run a Optima AGM in Parallel With a Walmart Deep Cycle Battery?

I was told the batteries need to match so they aren't fighting eachother.
 

JimS123

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Re: Run a Optima AGM in Parallel With a Walmart Deep Cycle Battery?

I'm lazy by nature, so I hate having to go out and buy stuff all the time. The Wally battery I bought lasted 2 years, so even at 1/4 the price its a looser. My Odyssey AGM lasted 4 years the first time and less than a year the second, so they are on the ships list. (The dealer had the same problem with a whole shipment that year).

I currently have 2 Deka AGMs that are on their 9th year, so its AGM all the way for me. I don't care about "cheap", all I care about is service life.
 

maczilla23

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Re: Run a Optima AGM in Parallel With a Walmart Deep Cycle Battery?

Can I run the agm in parallel with a deep cycle everstart without ruining them. thats all I need to know.
 

oldjeep

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Re: Run a Optima AGM in Parallel With a Walmart Deep Cycle Battery?

Can I run the agm in parallel with a deep cycle everstart without ruining them. thats all I need to know.

No. You need to have batteries that are the same if you run them in parallel.
 

ajax5240

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Re: Run a Optima AGM in Parallel With a Walmart Deep Cycle Battery?

Can I run the agm in parallel with a deep cycle everstart without ruining them. thats all I need to know.

No. Batteries should match. Not necessarily brand, but group and type. Group is size, type is lead/acid vs AGM
 

maczilla23

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Re: Run a Optima AGM in Parallel With a Walmart Deep Cycle Battery?

Ok I appreciate it! It may be more cost effective then just to get 2 everstarts. Sucks. IDK what im going to do with my optima now
 

matt167

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Re: Run a Optima AGM in Parallel With a Walmart Deep Cycle Battery?

Sell it, Everstart batteries are not too bad, but the extra cost for the Maxx/ extra warranty is worth it.. Walmart also sells Champion batteries which are made by Johnson Controls and are basicly seconds from the Interstate battery line but still better than the Everstart.
 

maczilla23

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Re: Run a Optima AGM in Parallel With a Walmart Deep Cycle Battery?

Sell it, Everstart batteries are not too bad, but the extra cost for the Maxx/ extra warranty is worth it.. Walmart also sells Champion batteries which are made by Johnson Controls and are basicly seconds from the Interstate battery line but still better than the Everstart.


Guess I could try on craigslist to sell it. I keep going back and forth thinking maybe I should just buy another optima to go along side this one. Just hate to for out 200 + for one.
 

Splat

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Re: Run a Optima AGM in Parallel With a Walmart Deep Cycle Battery?

Sigh.... NO NO NO NO NO! you can connect dissimilar capacity batteries in parallel with no problems long as they are the same voltage. I.e. both 12volt batteries. They can be different groups, sizes, capacities, colors, side terminal vs top terminal, they don't even have to like the others in-laws. In parallel they will equalize voltages and discharge at the same rate. If you have a 200 ah and a 100 ah in parallel, you now have a 300ah battery bank. They will always read the same voltage, and be at the exact same state of charge. Thus if you put a partially discharged battery in parallel with a fully charged one they will equalize some where in the middle. The larger capacity battery will take more of the load then the smaller one.

Where you may have a issue is during charging, and only because they are of dissimilar construction. AGM batteries have a different charging profile than lead acid. The proper way to charge would be to place a switch between them, and charge one on the lead acid setting of your charger then switch to the AGM and charge the other.

While were on the topic, running batteries in parallel doesn't exactly give you the amount of the two capacities added together. Due to internal resistance and some other big words I don't feel like typing out there is some loss of capacity. Installing a battery with between the two, and running one at a time will give you greater capacity, then running them in parallel.
 

jhebert

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Re: Run a Optima AGM in Parallel With a Walmart Deep Cycle Battery?

AGM batteries are lead-acid batteries.
 

maczilla23

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Re: Run a Optima AGM in Parallel With a Walmart Deep Cycle Battery?

Well I bought 2 Everstart Max Deep Cycle Marine Batteries. I will just use my optima as a backup/fishing battery. Thanks for all the help. Hopefully the maxes work out for me :)
 

Splat

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Re: Run a Optima AGM in Parallel With a Walmart Deep Cycle Battery?

AGM batteries are lead-acid batteries.
sigh...again... AGM or absorbed glass mat batteries are a specific type of lead acid battery, as opposed to a typical flooded lead acid battery. AGM batteries require a different charge profile different than a flooded lead acid. Specifically the float voltage is lower to help prevent excessive out gassing and prevent bubbles from forming in the fiberglass matting and exposing the plates to a dry state, causing corrosion.
 
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