AGM batterys

[jmagg]

Decided last year to go with a Duralast AGM battery for the pickup/plow truck, since I had been having trouble with batterys dying and or going dead prematurely. The truck sits for long periods of time these days. Winter is here and while the truck continues to start up, i thought i should top the battery off. I connected my oldish Schumacher charger (no AGM switch) and it showed on but did not act typically as with a standard battery.

On to the Goog, to see if a older charger will work with the AGM and most say it will, but dont over or undercharge, or it will damage the battery. I also couldnt find which setting to use on the AGM (SLI or Deep cycle) and if i should charge at 2a or 12a. I called the auto parts store that sold me the batt and I got 3 different answers from 5 of the store chains. I asked another store, and the clerk said he had talked to Johnson controls and the only way to charge a AGM battery with an school charger is to put a standard battery in between. I spent on an AGM charger, since the plow truck is essential to our winter life.
Thoughts pls and ty

 

[DaTT]

Is buying a new charger out of the question, for peace of mind?

 

[jmagg]

Yea, I bought before I posted, just trying to untangle the question and answers on charging AGM with older chargers.

 

[Torn Mind]

Absorbent Glass Mat (AGM) Battery Information - Battery University

Learn what differentiates Absorbent Glass Mat (AGM) batteries from other lead acid battery types

batteryuniversity.com

Any battery that sits for an extended period of time will experience premature wear, it is just slower with AGM.

SLI is just starting, lighting, ignition.

Getting a specific charger is indeed a must, preferably with temperature compensation.

 

[jmagg]

https://www.amazon.com/Schumacher-SC1304-Automatic-Battery-Charger/dp/B0756NVGHY

I see nothing about temp compensation, and I read not to charge a frozen battery so we'll see what transpires. It gets cold here with plenty days below 0.

 

[Torn Mind]

https://www.amazon.com/Schumacher-SC1304-Automatic-Battery-Charger/dp/B0756NVGHY

I see nothing about temp compensation, and I read not to charge a frozen battery so we'll see what transpires. It gets cold here with plenty days below 0.

The Noco Genius line has temperature compensation.
So does the BatteryMinder 2012-agm.
Ctek also makes some reputable chargers.

How were the flooded batteries treated with regards to charging?

 

[jmagg]

I charged them SLI 2A, and a jump in the cold when needed but that gets old real quick when its 10F.

I suspect it was an always on headlight control module causing the slow drain over the years which i've since removed. This year I plan to top the AGM battery off after every plow (which is my property only). The batt will be warm enough after cleaning up the driveway, Its an electric plow.

 

[echo4747]

Decided last year to go with a Duralast AGM battery for the pickup/plow truck, since I had been having trouble with batterys dying and or going dead prematurely. The truck sits for long periods of time these days. Winter is here and while the truck continues to start up, i thought i should top the battery off. I connected my oldish Schumacher charger (no AGM switch) and it showed on but did not act typically as with a standard battery.

On to the Goog, to see if a older charger will work with the AGM and most say it will, but dont over or undercharge, or it will damage the battery. I also couldnt find which setting to use on the AGM (SLI or Deep cycle) and if i should charge at 2a or 12a. I called the auto parts store that sold me the batt and I got 3 different answers from 5 of the store chains. I asked another store, and the clerk said he had talked to Johnson controls and the only way to charge a AGM battery with an school charger is to put a standard battery in between. I spent on an AGM charger, since the plow truck is essential to our winter life.
Thoughts pls and ty

I had a vehicle sit in storage for about 7 months with a 2-1/2 year old AGM battery that discharged to the point I thought it was completely dead ( had no response when i pressed the unlock button on my key fob.. I jump started the car drove it about 20 mins to my home and proceeded to charge it with and old fashioned (2& 10 amp) charger. I let charge for about 7 hrs. So far ( it been a little over 2 months) its been fine

 

[jmagg]

Bring on the snow

 

[BonzaiDuck]

I had a vehicle sit in storage for about 7 months with a 2-1/2 year old AGM battery that discharged to the point I thought it was completely dead ( had no response when i pressed the unlock button on my key fob.. I jump started the car drove it about 20 mins to my home and proceeded to charge it with and old fashioned (2& 10 amp) charger. I let charge for about 7 hrs. So far ( it been a little over 2 months) its been fine

Everyone has parallel yet varied concerns about these matters.

In So-Cal, we don't worry about freezing cold although some including me would welcome it. Instead, there's the summer heat. Someone told me that hot ambients will affect an AGM battery -- perhaps causing it to discharge faster. Not knowing the specifics on that issue, I'd noticed that all the times my AGM wouldn't crank the engine occurred in the July heat.

On the charger, those items which specially provide for AGM charging may cost a little over $200 -- more or less -- but that's the order of magnitude. Here's a top-end unit at Autozone. I have one made by Shumacher, which was probably less than $150. My most recent AGM battery -- a "deep-cycle" Optima Yellow Top -- cost me about $350 (as I recall). If one is convinced that AGM is "the way to go" (and I am . . . ), it is not a frivolous investment. It is worthwhile.

If you have an AGM that has discharged completely for any reason and needs to be recharged (it can take up to 24 hours), every complete discharge shortens the battery's expected life. (As . . I understand it . . ). You may actually surpass the warranty period or manufacturer's expectation, but if the battery has been discharged two or three times over that period, it's just as well to replace it with another.

That being said, a veteran mechanic I know who retired in 2018 had told me that it was just a good idea to throw the charger on the battery every so often -- a minor chore you could perform once a month, once every three months . . . twice a year.

 

[jmagg]

Well it started this morning at 11 degrees but a slow turn initially. Did I read that the initial CCA is somewhat less with AGM? Got it on the charger which shows 12.8 and 94%. Ill leave it on all day since we're expecting 12-16 but could be 2 feet.
Nor'easter tonight yeehaw.

 

[Torn Mind]

Well it started this morning at 11 degrees but a slow turn initially. Did I read that the initial CCA is somewhat less with AGM? Got it on the charger which shows 12.8 and 94%. Ill leave it on all day since we're expecting 12-16 but could be 2 feet.
Nor'easter tonight yeehaw.

Wiring corrosion and temperature affect cranking amps.

12.8 doesn't mean anything due to surface charge. You have to drain away the surface charge first to get the actual voltage reading, which should be 12.6 for a normal battery(2.1 volts for each cell, wired in series).

Batteries self-discharge. Therefore it is best practice to charge it frequently either by using the vehicle or periodic float charging.

 

[jmagg]

It started, plowed and is back on the charger. The charger says 96% but yesterday when charging it took about 4 hrs at 99% before it went into maintenance mode.

 

[thecoolnessrune]

It sounds like when you're using it for plowing, the Alternator isn't getting the battery fully charged up., which is fully expected under short duration, high power usage workloads. If it were me, I'd just consider installing an onboard charger like the Noco Gen5x1 and running the AC plug next to the Engine Block Heater power plug. Plug them both in when I'm done with it for the day, and call it good.

 

[jmagg]

It sounds like when you're using it for plowing, the Alternator isn't getting the battery fully charged up., which is fully expected under short duration, high power usage workloads. If it were me, I'd just consider installing an onboard charger like the Noco Gen5x1 and running the AC plug next to the Engine Block Heater power plug. Plug them both in when I'm done with it for the day, and call it good.

I do like this always attached solution ty. I may do this if the plug will reach out through the grill. If I need to open the hood to plug it in, may as well use the Schumacher I just bought.

 

[BonzaiDuck]

Here's a simple question about chargers and batteries. I'm seeking an opinion just in the event that I'm making bad assumptions or missing something.

The AGM charger instructions explain "charging with the battery out of the car" and "charging with battery in the car". I think one method involves a ground connection to the engine, while the former method involves simply connecting both charger leads to the battery terminals.

If I follow the instructions for "out of the car", do I have to lift the battery from the engine compartment? Why -- if charging "in the car" is the alternative method -- can I not simply connect the cables to neg and pos terminals -- without removing the battery from the car? Why would there be some safety issue that emerges from the way you connect the charger? I don't see a problem with leaving the battery in its engine-compartment tray . . . .

Whoops and oh . . . .I forget to be more specific. Using the "out of the car" method with the battery still in the vehicle, I would remove both of the vehicle leads from the pos and neg terminals before connecting the charger . . .

 

[Meghan54]

Seems AGM batteries can vent gas in some circumstances, ending up acting like a flooded lead acid battery, i.e. flooded batteries are known for off-gassing hydrogen during charge and discharge. An AGM can over-pressure and vent, setting up the same exact scenario you have with flooded lead-acid batteries...explosive hydrogen gas lingering, waiting for a spark. One way you can get this to happen is by charging too quickly. Doing that produces hydrogen faster than can be absorbed by the glass mat. Keep this up long enough and you can over-pressure the battery and force it to vent.

That'd be my guess as to why the charging instructions mirror flooded lead-acid batteries.

 

[BonzaiDuck]

Seems AGM batteries can vent gas in some circumstances, ending up acting like a flooded lead acid battery, i.e. flooded batteries are known for off-gassing hydrogen during charge and discharge. An AGM can over-pressure and vent, setting up the same exact scenario you have with flooded lead-acid batteries...explosive hydrogen gas lingering, waiting for a spark. One way you can get this to happen is by charging too quickly. Doing that produces hydrogen faster than can be absorbed by the glass mat. Keep this up long enough and you can over-pressure the battery and force it to vent.

That'd be my guess as to why the charging instructions mirror flooded lead-acid batteries.

So you would say "remove the battery from the car"? Then how or why is there a set of instructions for charging the battery in the car? How would that be any different?

 

[jmagg]

So you would say "remove the battery from the car"? Then how or why is there a set of instructions for charging the battery in the car? How would that be any different?

From what I gather, having accessories on in the vehicle ( Instructions stress having all accessories off before charging) ( some newer cars draw down with the car off) while connecting may cause a small spark, as compared to a batt with no draw at all. I believe this is why the "connect to block" instruction is called out in the instructions while in car to avoid any spark near the batt. If connecting in the car with the batt disconnected, there should be no spark, and the same as out of vehicle. I assume all of this.

 

[Meghan54]

So you would say "remove the battery from the car"? Then how or why is there a set of instructions for charging the battery in the car? How would that be any different?

No, wouldn't remove the battery from the car. Instead, be cognizant of the fact that it may build up a little hydrogen gas in the space it's sitting in and work appropriately. If the space would be prone to buildup of vapor, work differently than if the space is similar to working open air.

That's why the "put the negative clamp on a remote grounded spot from the battery" is the standard routine for charging in vehicle...and is not the routine when out of the vehicle.

 

[BonzaiDuck]

No, wouldn't remove the battery from the car. Instead, be cognizant of the fact that it may build up a little hydrogen gas in the space it's sitting in and work appropriately. If the space would be prone to buildup of vapor, work differently than if the space is similar to working open air.

That's why the "put the negative clamp on a remote grounded spot from the battery" is the standard routine for charging in vehicle...and is not the routine when out of the vehicle.

Electric motors generate sparks, or so I imagine. But if I put a Ryobi cannon fan at one garage door, blowing air out the main door, any hydrogen would get blasted out and away from the fan with other air . . .

I just want to make it an easy routine for charging our batteries on a monthly basis, without any "heavy lifting". . . . Taking batteries out and away from the vehicle is heavy lifting . . .