Just replaced Flooded battery with AGM, was that a mistake?

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My 2013 stock battery was starting to struggle on cold mornings after the car mostly sits on the weekends. Got it measured around 240CCA and decided that it was time for a new one. Got a JC made Champion AGM at PepBoys for $90 after I get the $50 rebate.

Car is already noticeably starting better. I'm reading conflicting evidence online about whether an AGM is a drop in replacement for the Flooded. Someone ease my mind because I could have bought a flooded Interstate at Costco for $80 with no rebate nonsense.
 
AGM are good long lasting batteries. I just replaced the original battery in my 2011 Jetta this past spring at 150k miles
 
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Any remotely modern vehicle has a charging system tightly enough regulated that it can safely charge AGM designed for vehicle use such as that one is. Really old vehicles that may get up closer to 15V charge voltage should not use an AGM unless you put a regulation/drop circuit between them.
 
Originally Posted by PowerSurge
AGM's are better for cold climates. Wet cells are better for hot climates.


AGMs are better in cold and hot climates.
 
I've used AGMs in two vehicles not explicitly designed for AGM use and I didn't see much if any benefit. I have a 2008 BMW that allows me to change the charging profile to accommodate the needs of an AGM...I took advantage of Pepboy's black friday sale and bought an AGM and I expect this battery to do better than my two other vehicles that did not allow me change the charging profile did with AGMs.
 
So bottomline: your car will be fine but it's unlikely you'll see double the life out of the battery or anything like that. I didn't when I used AGM batteries in my vehicles that originally came with FLAs.
 
Originally Posted by CharlieBauer
Originally Posted by wymi516
https://www.youtube.com/watch?v=h7rTcBanpMk


Whole test was flawed by not topping them up correctly at the beginning.



yup

agm typically require 14.7 vs 14.4 volts and his charger did not differentiate - therefore the AGMs never got fully charged.

UD
 
I picked up a Pro-Logix 2310 which has different logic for AGM and FLA, plus does 6V, 12V, and power supply modes. This has charge rates of 2-6-10A... they also make the 2320 which has 2-10-20A. You can now find the 20A version for the same price I paid for the 10A. Since it's a "smart" charger, you can also use it as a maintainer and leave it connected long-term if you have a stored battery without worrying about frying the plates.
 
Originally Posted by CharlieBauer
Originally Posted by PowerSurge
AGM's are better for cold climates. Wet cells are better for hot climates.


AGMs are better in cold and hot climates.


Negative ghost rider.
 
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Pennsylvania so no extreme heat other than a few days in July and A few days in January in single digits. On the other hand, can someone decode the manufacture date from this battery. I took several pics...

https://imgur.com/a/ovJIFwQ
 
Originally Posted by jayjr1105
Pennsylvania so no extreme heat other than a few days in July and A few days in January in single digits. On the other hand, can someone decode the manufacture date from this battery. I took several pics...

https://imgur.com/a/ovJIFwQ


October 2019
 
Originally Posted by PowerSurge
https://www.consumerreports.org/car...ts-your-car-battery-what-to-do-about-it/

"But even AGM batteries face challenges. "AGM batteries will perform well in the heat, but the life span will be hampered due to loss of water from the high temperatures,"

FLA's last longer in hot climates.


This makes zero sense unless they are essentially abusively charged.

AGMs, which are also valve regulated lead acid batteries, are designed to fully recombine the formed hydrogen and oxygen inside. The "valve" prevents escape.

They can overpressurize on charging and lose gas. Recall that coulombs and amperes relay numbers of electrons. Electrochemical reactions are reliant upon mass - quantity of reactant to create those numbers of electrons in the circuit. If charged too fast, ie too many amperes, the overpotential (voltage) must be higher. This gives a one-two punch. Higher voltage which drives the electrolysis reaction, and more current which means more electrolysis can happen. Too much happening (faster splitting than recombination) will create pressure. Simple concept. Then the burped has, which should have recombined to water, is lost forever, impossible to add back.

So it is possible. But I'd suspect it needs to be a very fast charge on a very high impedance battery. In normal use, they should not lose appreciable water.
 
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