AGM Battery Question

Hey guys, I’ve been running an AGM battery the last 3.5 years. Never bothered to get a tune. Recently when leaving the mountains it took a couple more cranks than usual to start up, so I think it’s time to replace. I do not want to go back to acid, I have had leaks and corrosion issues in the past. I live where temps can reach above 120 in the summer and below freezing in the winter (hell).

I’ve read a lot of people without tunes will charge their AGM battery monthly to account for the lower voltage of the alternator. I have not done this. Would buying a charger now and charging my battery milk some more life out of it? Or is it just time to replace? Thanks

 

Im Curious as well, I have a AGM . I dont mind charging it every weekend or monthly. I have two trucks a car and a motorcycle, So the Tacoma can sit for a bit.

 

Used a yellow top optima age battery and only lasted 3 years when it started to crank really slow and heard that I had to top off the battery since the truck won’t charge up to 14.5 volts or something.

 

I lived in Alaska for 20 years, and never has issues with the regular flooded cell batteries. Now in GA (hot and humid 6 month a year), and still no problems with the regular batteries.
I put felt terminal protector washers on the battery (to block any acid fumes) and coat terminals in dielectric grease or battery spray. No corrosion of any kind.

 

If you have a buddy with a NOCO charger, run the repair mode and then do an AGM mode charge. Run that for a while, odds are the battery is okay but needs a little love.

 

I’ve been running an AGM battery for over 6 years, no tune, no separate charging, no issues yet. I will definitely replace it with another one when she goes.

 

I am new to Toyota and Tacomas... But I don't know what a "tune" involves... Please learn me.

The idea does make me scratch my head though.
If a normal alternator on nearly any car is expected to output between 13.5 and 14.45 Volts @ somewhere between 70 and 180 AMPs.
Manufacturers of trucks/SUVs issued standard alternators on all models with some kind of upgrade to higher output alternators for towing and/or off-road option packages.
Under normal conditions, the 12V battery would get enough juice to run engine and normal accessories and still heave enough juice to charge the battery and keep it charged up for you.

Why would an AGM need to charge weekly and why would original or even optional upgrade alternators require a "tune" in order to run the vehicle and charge the battery?

Not trying to be a wise guy here... I had Optima Red Top AGM in my TJ Rubicon for 2 years, then transferred to my 04 Tahoe for another 3 years. In 5 years, the battery was always charged adequately and was great for me.

I feel like I just don't get what would require a tune or extra charging every week to run an AGM battery.
Are we talking a second battery for high-powered accessories like a gigawatt amplifier or some kind of low-rider airbag wheel-hopping suspension?

 

The stock Taco charging is at about 13.6v or so. AGMs get full capacity at about 14.2v or more. That detail will be on the battery label.

Lead acid is 13.3v at full charge capacity.

As the charging is ECU controlled on the 3rd Gen, a tune can increase the charging into that range. This get folks to full capacity of the battery.

 

Many here will say that an AGM battery requires a special tune to properly charge. And many here will say that it does not matter one bit either way. Both sides will cite evidence for these claims. I personally have no clue, but I will always default to what benefits my wallet the most, which is a standard Wally World EverStart. It is the best value bar none when it comes to batteries for these Tacos.

But as always, what the hell do I know?

 

You could try to charge it and/or have it load tested. The worse that happens; your battery is in fact DOA and you have a charger/maintainer to maintain your new battery. A battery charger and jump pack is a must for me, it's like having a screwdriver and hammer.
My Tacoma doesn't get used much, so during the winter it sits on a NOCO

$50 GENIUS2 : 2A 6V/12V Smart Battery Charger – Automatic Maintainer, Trickle Charger & Desulfator with Overcharge Protection & Temperature Compensation – For Lead-Acid & Lithium Batteries

GENIUS2 and I sporadically put it on during the rest of the year. Thanks for the reminder, it's time! It's been a while and never hurts to pop-a-charge.
In the end, you got 3.5 years so it could just be time anyways.

GL

 

I’d say to replace it giving the fact that it started giving you issues when trying to start up. What AMG battery are you running on your truck?

 

Get a NOCO Genius 10. It will charge, maintain and boost your AGM battery. They are called Genius for a reason, the unit reads your AGM battery and adjusts to the perfect charge/re-charge, maintenance, float, de-sulfate setting for your battery. We've got the 2 amp and the 10 amp for our AGM's and have been using them for over 10 years. None of the AGM's have ever had issues.

 

Charging the AGM battery below its optimal charging voltage just means you don't get the full Wh capacity of the battery; it doesn't shorten the battery's life. The 120F summers tend to kill batteries sooner. Time for a replacement.

 

It's my understanding that AGM batteries benefit from the occasional battery tender overnight. Especially in older trucks that aren't really designed for them. I'd try that and if it brings it back do so at night once a week.

 

That's a lot of work to keep a battery. If AGM lasts 3.5 years, why not just get a regular flooded cell cheaper and get the same 3.5 years?

 

The older Tacos (2nd Gen and such) can do simple jumper (Gray Wire) and relay mods to increase the charge voltage.

 

I looked at Interstate wet and AGM at Costco. They don't sell any product without some serious testing before they add stuff to their shelves. It has been 5 years at least since I last bought batteries. When I went looking the other week, I was surprised to see everyone has 3 YR batteries now and that was the best class no matter which brand. No more 36/48/60 month batteries to be seen... 3 years is it.

Like I said, Costco has a solid reputation for product quality and product testing. While some people may not be Interstate Battery fans, the first one I bought was an Interstate 6V for my dad's Model A Ford. That same battery lasted more than 10 years.

I saw Costco has wet battery for about $149 and AGM for about $179. Both were 36 month guarantee batteries with full replacement. I may get a wet one from there before winter comes to New England.

 

Several years ago a last virgin lead refiner and smelter closed in the US. Now we have capacity only to reclaim lead from old batteries, not to refine lead from ore.
IIRC at one point I was told that better/longer lasting batteries need virgin, unused lead for their plates.

 

$40 SOLPERK Solar Panel Kit 20W 12V, Solar Battery Trickle Charger Maintainer + Upgrade Controller + Adjustable Mount Bracket for Boat Car RV Motorcycle Marine Automotive

https://www.amazon.com/SOLPERK-Main...prefix=solar+battery+tend,aps,148&sr=8-4&th=1

You can do it off of solar. You can top it up pretty easily here and there with a solar panel and MPPT controller of some sort.

I have a fridge running off of mine so I have a 100W panel mounted permanently to the roof rack, but you could do a fold out just as easy. Or even a little 20W with a controller will keep it topped up to the right voltage. Or, a tune can do the same thing. I knew I was going to have the fridge shenanigans and need a solar panel anyway so I didn't bother with a tune.

 

I have the same battery and it's now 8 yrs old. I do have the HKB voltage booster fuse which tricks the alternator to getting another 0.5 volts, so I usually see between 14.3 to 14.7 volts while driving. I've only once put it on my NOCO Genius charger and that was after the truck sat for 3 months. I stop in at O'Riellys occasionally for their free battery load test and every time they say good as new. Considering how much these batteries cost I'm hoping to get 10 years out of it.