AGM vs traditional batteries. Are AGM better?

[Linda]

Having seen that RockAuto now offers batteries, I am wondering if the AGM batteries are better. Any experience?

[Alvin]

Having seen that RockAuto now offers batteries, I am wondering if the AGM batteries are better. Any experience?

Great question Linda! I'm curious too. I've had the same Optima yellow top battery in my roadster for 15 years now. I want to know what to replace it with.

[RCMike]

Don't replace it Alvin. The new ones only last about 3-4 years.. They moved the factory and the new are junk..

[Cyclewrks]

Big advantage to them is weight and size, they are lighter and smaller. They also are sealed so they don't leak (which means you can mount them in any position, mine is mounted on its side in the trunk) nor do they weep sulfuric vapor (helps cut down on corrosion in trunk mounts). For cars that aren't driven regularly they are said to hold a static charge longer. Not sure if it is true or not but it seems that they hold up to vibration better, back when I raced I had occasional issues with the internal connections between the cells coming loose in standard flooded cell batteries and have never seen it in an AGM.

[Linda]

All sounds good so far. How long do they last? Can you jump start them like a traditional battery?
Battery prices sure went up in the last few years .
Linda

[JohnnyMac]

I had an Optima in my daily driver for about 5 years. Stopped to get gas, and it was dead. No slow cranking, dimming lights, or any warning, just dead. And it could not be jump started. I haven't gone back to them since. However, if mine had lasted 14 years, I would get another, except I wouldn't need to because it would still be working.

[Cyclewrks]

Jump starting is the same, charging them is similar though certain brands are more finicky than others, they do NOT do well if they are overcharged. That is the quickest way to kill one. Most of the stuff I have seen put the cycle life of an AGM battery at 2+ times that of a conventional battery.

[Alvin]

This is my yellow top Optima:

It has been dead twice from leaving lights on. Other than that no problems for 15 years. I started using a cut-off switch about 5-years ago. Maybe that helped. Recently noticed weaker starts in winter.

Don't replace it Alvin. The new ones only last about 3-4 years.. They moved the factory and the new are junk..

That's unfortunate! Started browsing Braille, Lithium and regular batteries. Also considered hydrogen:

[Toptech360]

comparing agm vs flooded batteries is very similar to comparing synthetic oil to conventional oil...agm is premium technology with improved performance qualities that may or may not be of any real benefit when considering the premium price.

I run a large (group 31) agm battery in my Toyota truck. Its got a winch and other accessories and I rely on the truck in severe weather and in remote areas so I wanted the best. All my other vehicles have premium regular flooded cell batteries.

Optima batteries have been made by Johnson controls for several years now. The people that sold optima still make premium top end batteries under the name odyssey batteries. Premium battery premium price!

Most battery brands are made by a few different manufacturers. They are all rebadged mostly. These days 3-5 years is average life though I still see batteries 8-14 years old that still work. like most things the worse thing for a battery is to let it sit...

[mlwebb]

Batteries age(die) from sitting with a partial charge. Keep them fully charged between uses and they last a long time. Typically an alternator does a good job of this (on a daily driver). I think agm batteries are more reliable for vehicles that aren't driven daily, or at least weekly. If your looking for something lightweight, any of the big road bike batteries would work. The smaller the battery, the more useful a BatteryTender, or smart charger to keep an eye on it is. I have an on board charger on my boat, so I can just plug it in, considering one for the roadster (:
Michael

[SLOroadster]

I've had a little Odyssey PC680 in my car for a good 15 years. I'm now on my second one, but I think the first one is still good. (I'm going to give it a try in my '59 Alfa when the time comes) I've never had an issue with either battery. I thought the battery was done 10 years ago, but it was the starter that was done. (Replaced the battery and the car still didn't start until I put a new starter in.) A friend of mine has one in his Alfa that sits most of the time. (It might see 50 miles a year) The car always starts and doesn't get run that much.

I'll never run a normal lead acid battery again. There is no point. They are expensive to buy, but they last a LONG time.

Will

[pebbles]

Alvin, I had a red top optima in my sand rail for ten years. Fabbed the tray specific. Sadly the new optima didnt fit by about 5mm. So I went with the slightly smaller odyssey.
I also purchased a NOCO genius G3500 charger/tender. Has multiple charge modes, 6v/12v, standard, AGM and Lithium.

[pebbles]

Having seen that RockAuto now offers batteries, I am wondering if the AGM batteries are better. Any experience?

No leakage

[Linda]

I also purchased a NOCO genius G3500 charger/tender. Has multiple charge modes, 6v/12v, standard, AGM and Lithium.

So AGM batteries require a different charging mode?
Linda

[Toptech360]

Using a "smart" charger like the noco genius is preffered for charging an agm out of the car. Otherwise in the car the alternator doesn't know or care what kind of battery its charging.