1 agm battery vs 2 x lead acid whats the better buy?

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hey guys im going to be replacing my vehicle battery soon and here in canada, its harder to find batteries and we dont get them that cheap.
pushing warranty aside, i can either get 2 x costco lead acid batteries meaning when 1 fails i can just buy another one for about the same money as buying 1 energizer agm battery.

do you think an energizer agm battery can last 2 x more?
i feel like its a no brainer to save the extra money and keep buying lead acids since the agm is 2x the cost

this is keeping warranty aside as they both have similar warranty thru costco. so i just want to compare the product.

correct me if im wrong
thx
 
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Does it get real cold there? Does the AGM have an advantage in cold cranking that you could use?

Would you feel funny pushing the AGM into year 10 or whatever your goal is, or would you chicken out and replace it anyway?
 
Originally Posted by eljefino
Does it get real cold there? Does the AGM have an advantage in cold cranking that you could use?

Would you feel funny pushing the AGM into year 10 or whatever your goal is, or would you chicken out and replace it anyway?



yeah in winters it gets really cold -40 celcius basically
but you are right i guess i wouldnt want to keep an agm into year 10 unless that is normal life expectnacy for an agm which i dont believe it is

i am heavily leaning towards getting a lead acid, seems lile its going to be a better buy and with costco i can just replace it in 4 years regardless. they are great with warranty. and tbh this vehicle probably wont even be driven that much after the next couple years so not sure if that would affect anything
 
Originally Posted by apollo18
Originally Posted by eljefino
Does it get real cold there? Does the AGM have an advantage in cold cranking that you could use?

Would you feel funny pushing the AGM into year 10 or whatever your goal is, or would you chicken out and replace it anyway?



yeah in winters it gets really cold -40 celcius basically
but you are right i guess i wouldnt want to keep an agm into year 10 unless that is normal life expectnacy for an agm which i dont believe it is

i am heavily leaning towards getting a lead acid, seems lile its going to be a better buy and with costco i can just replace it in 4 years regardless. they are great with warranty. and tbh this vehicle probably wont even be driven that much after the next couple years so not sure if that would affect anything


Not sure where your battery is. Mine is in the trunk and it's an original factory AGM battery that's 12 years old. It's a JCI battery. In the US it's a no brainer to get an AGM because it's only around 20% more for the AGM, not 100%. Plus Pepboys tends to have good rebates so if you catch it on sale, it's almost as cheap as a regular battery. In your situation, I would just get a regular JCI lead acid battery.
 
Unless your application requires AGM, you are much better off with buying two conventional lead acid batteries.
 
All lead acid batteries degrade over time. As most of us know, properly cared for conventional batteries may have wildly varying lifespans. Some of that may be due to build quality and material quality. The latest Costco battery I have in my 2009 F150 in FL has held up well at 4 years now, that truck kills batteries, often 1.5-2 years. Each cycle was different...

AGM's are said to have twice the lifespan. However, it's good to remember that while they still work and are not as likely to suddenly fail (due to construction) , AGM battery capacity degrades just like any lead acid battery. An old AGM won't have a lot of reserve power.

Our 2 year old Concorde AGM's on our PC-12 aircraft, just tested at 94% and 91% of rated AH capacity. But remember those batteries tested at 130% or more when new. (last year they tested over 100%) So they sandbag, to make the batteries seem to last longer. Degradation over 2 years is over 30%. Next year, they will test below 80% (the limit) and will be discarded.


Let's put that another way, after 3 years, each of those $4000 super high quality AGM's will have 62% of original capacity. That's the reality of lead acid batteries. It's also good to note that chinese flooded lead acid car batteries are known to have very short lives.
 
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It depends on a couple of things. A lead acid battery needs to be fully charged at least once a year. Otherwise it will degrade quickly. It can't be fully charged at 14.4 volts what most cars have. An AGM battery can be fully charged at 14.4 volts. It just takes long time. Another factor to consider - the voltage your alternator provides. If it is 14.0 V or lower than a lead acid battery won't last long. 3-4 years max. You need to charge them manually at least twice a year to keep them alive. So if you can recharge the batteries regularly than a lead acid battery is your choice. If you want to buy and forget for a number of years than an AGM battery may outlast 2 or even 3 lead acid batteries.
 
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AGM is more resitant to vibration, is leakproof, can deliver higher CCA, lower discharge rate and no gasing. But the charging voltage is higher otherwise, you never fully charge the battery. And you can mount them in any orientation.

It is also more expensive.

Either typre needs charging once a month when in storage unless they have not been activated
 
All lead acid batteries degrade over time. As most of us know, properly cared for conventional batteries may have wildly varying lifespans. Some of that may be due to build quality and material quality. The latest Costco battery I have in my 2009 F150 in FL has held up well at 4 years now, that truck kills batteries, often 1.5-2 years. Each cycle was different...

AGM's are said to have twice the lifespan. However, it's good to remember that while they still work and are not as likely to suddenly fail (due to construction) , AGM battery capacity degrades just like any lead acid battery. An old AGM won't have a lot of reserve power.

Our 2 year old Concorde AGM's on our PC-12 aircraft, just tested at 94% and 91% of rated AH capacity. But remember those batteries tested at 130% or more when new. (last year they tested over 100%) So they sandbag, to make the batteries seem to last longer. Degradation over 2 years is over 30%. Next year, they will test below 80% (the limit) and will be discarded.


Let's put that another way, after 3 years, each of those $4000 super high quality AGM's will have 62% of original capacity. That's the reality of lead acid batteries. It's also good to note that chinese flooded lead acid car batteries are known to have very short lives.
I’m researching AGM vs lead acid right now and am finding most independent battery experts are claiming lead acid outlast AGM. I was all about getting AGM because I don’t want any chance of leakage rusting my rust free van but if they are not going to outlast a lead acid I’m not paying double the price. The only ones I’m finding claiming agm outlast lead acid are companies that only make agm like optima.
mid love to here some info on what really last longer.
 
AGM is more resitant to vibration, is leakproof, can deliver higher CCA, lower discharge rate and no gasing. But the charging voltage is higher otherwise, you never fully charge the battery. And you can mount them in any orientation.

It is also more expensive.

Either typre needs charging once a month when in storage unless they have not been activated
My research is showing that the agm delivers less cranking amps than lead acid. I’m comparing group 65 best lead acid vs group 65 agm the lead acid 850cca while the AGM is 750. I’ve found the same differences comparing the 2 at 3 different places with their group 65 vs their best group 65 lead acid. At all 3 places the lead acid has 3 choices, good better and best. The best outperforms the agm and the mid grade lead acid is equal to there AGM.
I’m finding it very hard to spend double the price for AGM when before I started researching I thought agm were far superior.
 
I’m researching AGM vs lead acid right now and am finding most independent battery experts are claiming lead acid outlast AGM. I was all about getting AGM because I don’t want any chance of leakage rusting my rust free van but if they are not going to outlast a lead acid I’m not paying double the price. The only ones I’m finding claiming agm outlast lead acid are companies that only make agm like optima.
mid love to here some info on what really last longer.

I have two AGM batteries. One is 13 years old and the other is 10. One is an H8 and the other is an H6. They're both Varta batteries which was made by JCI. You'd be hard pressed to find lead acid lasting that long. Main issue these days is that alternators don't fully charge up batteries anymore and that leads to an early death. They do that on purpose for better CAFE numbers. Less charging means better gas mileage.
 
I’ve bought several agms. they are not infallible. The only one which failed, I knowingly bought at 8 months old off the shelf. I figured it would quit under warranty, which it did. The others have been solid. I just bought a deep cycle for the travel trailer, and at batteries+ (east penn batteries!) the agm gets a 3 yr warranty over the standard 1 yr. pricey, but I’m trying the agm. It gets used.

i really don’t know if they will hold much advantage in the current charging strategies which tend to leave them undercharged.

there’s less risk for the OP to buy the lead acid, but you might enjoy the knowledge from trying something different.

m
 
I’m researching AGM vs lead acid right now and am finding most independent battery experts are claiming lead acid outlast AGM. I was all about getting AGM because I don’t want any chance of leakage rusting my rust free van but if they are not going to outlast a lead acid I’m not paying double the price. The only ones I’m finding claiming agm outlast lead acid are companies that only make agm like optima.
mid love to here some info on what really last longer.
My AGM batteries lasted 7+ years except for the Autozone ones.
 
Agm batteries, are lead acid batteries.

Call standard batteries wet, or flooded.

Agm can be superior.....if they are truly fully charged often.
No lead acid battery is immune to living life chonically undercharged.

Defects aside. The worst battery kept fully charged or nearly so will greatly outlast one kept chronically undercharged.

It takes no less than 3.5 hours to charge an 80% charged battery to 100%. That is when it is newer and still healthy and the charging source can hold mid 14v the enture 3.5 hours. Older less healthy and lower voltage. Time to full can take 10x as long.

If you want any lead acid battery to last a long time. Insure they are fully charged often, and immediately after any deeper discharge.

How well or poorly a vehicle takes care of its battery has far too many variables for any blanket sttement to have any grain of truth/repeatability.

Agms have been cheapened as much as possible to be attractive for starter battery duty. The cheapest agms have neither the lower resistance /higher cca, or super low self.discharge of higher dollar agms.

Also CCA tests assume a 30 second load. When engine starting takes 2 seconds or less. The cca figure becomes misleading. The pulse cranking amp figure is often touted by high $ agms as more representative as an agm with a lower cca figure than a strter flooded battery, can easily spin a starter faster and maintain higher voltage during that 140+ amp sub 3 second load.

Don't lump a rebranded deka intimidator .or.similar low. $$ agm or any 50% more expensive ( than same group size flooded) agm, with an Odyssey lifeline or Northstar, and do not Mistake Optima with Odyssey, as while long ago Optima were built quite well and were very resilient... That ship has sailed.

The latter 3 are 2x the price and are mil-spec build quality. But they are not immune to a living their life chronically undercharged..In deep cycle duty they require high amperage recharges from their most depleted state or they lose capacity and performance quickly, and are not worth their premium price.

If one's charging system is subpar and they can wont dont apply.other charging sources to insure a true full charge somewhat regularly... They are better off with the cheapest battery with best warranty
 
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