AGM battery maintainer.

Joined
Feb 25, 2009
Messages
326
Location
TX
Should a regular off the shelf pocket sized trickle charger work on these batteries without issue?

I just got a warranty exchange through an Interstate Battery distributor for their ECONO line of refurbished ones and they pulled out an AGM instead of a FLA.
 
Should a regular off the shelf pocket sized trickle charger work on these batteries without issue?

I just got a warranty exchange through an Interstate Battery distributor for their ECONO line of refurbished ones and they pulled out an AGM instead of a FLA.
I hope when you say "trickle charger" that it actually is microprocessor controlled to prevent overcharging and goes into a float charging mode once the battery is fully charged. Old school trickle chargers should be avoided.

If it is a more modern "wall wart" battery tender with a float mode, but designed for flooded batteries, it will work okay. AGM algorithms will charge to a slightly higher voltage and float a bit higher as well. Not a huge deal for occasional use. I mostly have dedicated battery tenders with for AGMs, or have a specific AGM setting. You will be fine with one for flooded batteries.
 
Should a regular off the shelf pocket sized trickle charger work on these batteries without issue?

I just got a warranty exchange through an Interstate Battery distributor for their ECONO line of refurbished ones and they pulled out an AGM instead of a FLA.
Which charger(s) are you considering? As said, it will depend on the type of charger/maintainer. What is the battery going into that you may need a "trickle" charger for it?
 
To fully charge and AGM battery you need a minimum of 14.5 volts and to float charge no more than 13.5 volts.

The issue with under charging AGM's is that in the normal course of a battery discharging, soft lead sulphate crystals are deposited on the plates. When the battery is fully charged again these crystals are removed. However should the battery be left partially discharged or not be fully charged due to insufficient charging voltage then some of the soft crystals turn to hard crystals that are difficult to remove. The battery is said to be sulphated which reduces its life.

In summary you need to apply 14.5 volts to fully charge an AGM. It's not that it won't work if you apply less but it's life will be compromised. It's all down to looking at the specification of the charger.
 
I’ve used a Schumacher microprocessor controlled SC1355 2 amp maintainer for 3 plus years on my Harley Superglide AGM battery and it’s worked fine. The instructions state it’s OK for AGM batteries. It’s hooked up 90% of the time but now I’m wondering if it’s the right maintainer for the job:unsure:.
 
To fully charge and AGM battery you need a minimum of 14.5 volts and to float charge no more than 13.5 volts.

The issue with under charging AGM's is that in the normal course of a battery discharging, soft lead sulphate crystals are deposited on the plates. When the battery is fully charged again these crystals are removed. However should the battery be left partially discharged or not be fully charged due to insufficient charging voltage then some of the soft crystals turn to hard crystals that are difficult to remove. The battery is said to be sulphated which reduces its life.

In summary you need to apply 14.5 volts to fully charge an AGM. It's not that it won't work if you apply less but it's life will be compromised. It's all down to looking at the specification of the charger.
In my '12 Sienna van the last AGM lasted almost 8 years, It still passed testing but I replaced it just in case. My wife's AGM (Suzuki Kizashi) lasted 6 years and started to fail testing so it was replaced. Neither vehicle is AGM specified. Just the other day on Mechman dotcom I saw alternator harness with the diode built in for higher charging voltages, Installed in both vehicles and now have the higher charging voltages and batteries went from 83-85% charged to 92-96% charged according to my Chicom battery tester. At the 83-85% level it cranked fine and voltage drop cranking was fine, Now the voltage drop is a little better with the higher charging level.

Mechman also has a even higher voltage harness for lithium battery charging available.

This harness fit both my sienna and the kizashi: https://www.mechman.com/h113-l-2-vo...-batteries/?searchid=296127&search_query=h113
 
Should a regular off the shelf pocket sized trickle charger work on these batteries without issue?

I just got a warranty exchange through an Interstate Battery distributor for their ECONO line of refurbished ones and they pulled out an AGM instead of a FLA.
What does the manual for the trickle charger say?
 
i have a noco 10amp mounted in my amp rack on my truck. stays plugged in 100% of the time my truck is parked. maintains 3 AGM batteries, oldest of which is now 5 years old.
 
I use a conventional LAB(lead acid battery) charger/maintainer to keep 2 AGM batteries charged up when parked. It may not be the most optimal charging for AGM batteries however it does work very well. I’ve been doing this for several years.
 
I use a AGM battery in all the motorcycles I've owned for the last 20 or so years. I also use a Battery Tender brand charger. It's about the size of a older phone charger. It does what it's advertised to do, and that is to extend the life of your battery. It was frustrating getting 2 years out of a battery that cost $150 from the dealer. I've gotten over 6 years out of a MC battery. by using the tender. Every time I put the bike away, it gets plugged into the tender. It's main purpose is for keeping a battery hot, during extended periods of inactivity. They will also work for people with classic cars, race cars, boats, and RV's that sit for months. They make different models for bigger batteries, and have a bank type setup if you have more then one to keep charged. Just plug it in and forget it.,,
 
Should a regular off the shelf pocket sized trickle charger work on these batteries without issue?

I just got a warranty exchange through an Interstate Battery distributor for their ECONO line of refurbished ones and they pulled out an AGM instead of a FLA.
Many of them have an AGM mode, even the less expensive ones.
 
I use a AGM battery in all the motorcycles I've owned for the last 20 or so years. I also use a Battery Tender brand charger. It's about the size of a older phone charger. It does what it's advertised to do, and that is to extend the life of your battery. It was frustrating getting 2 years out of a battery that cost $150 from the dealer. I've gotten over 6 years out of a MC battery. by using the tender. Every time I put the bike away, it gets plugged into the tender. It's main purpose is for keeping a battery hot, during extended periods of inactivity. They will also work for people with classic cars, race cars, boats, and RV's that sit for months. They make different models for bigger batteries, and have a bank type setup if you have more then one to keep charged. Just plug it in and forget it.,,

The AGM in my motorcycle just failed this week after 11.5 years. I keep it charged but I'm not a fan of having it permanently hooked up to a float charger. AGM's don't need it as one of the great benefits of AGM over a wet cell is they have very low self discharge rate. The spec on my last battery was it would retain 91% charge after 3 months. If I've not used the bike for weeks on end I just pop it on the charger and it reaches full charge in a few minutes. I believe that's kinder to the battery than permanent float charging particularly if the the float charge voltage is not exactly right for the particular battery.
 
The AGM in my motorcycle just failed this week after 11.5 years. I keep it charged but I'm not a fan of having it permanently hooked up to a float charger. AGM's don't need it as one of the great benefits of AGM over a wet cell is they have very low self discharge rate. The spec on my last battery was it would retain 91% charge after 3 months. If I've not used the bike for weeks on end I just pop it on the charger and it reaches full charge in a few minutes. I believe that's kinder to the battery than permanent float charging particularly if the the float charge voltage is not exactly right for the particular battery.
Modern cars and motorcycles have a considerable parasitic draw due to the various ECUs and modules. AGMs cannot overcome that, and will require periodic charging or a continous float charge to remain ready for use. This is particulary the case for cars rarely driven or "short tripped" never leaving their immediate neighborhood. If the car or motorcycle is daily used, this is not a concern.
 
The AGM in my motorcycle just failed this week after 11.5 years. I keep it charged but I'm not a fan of having it permanently hooked up to a float charger. AGM's don't need it as one of the great benefits of AGM over a wet cell is they have very low self discharge rate. The spec on my last battery was it would retain 91% charge after 3 months. If I've not used the bike for weeks on end I just pop it on the charger and it reaches full charge in a few minutes. I believe that's kinder to the battery than permanent float charging particularly if the the float charge voltage is not exactly right for the particular battery.
To clear things up for you, the tender doesn't keep a constant charge going into your battery. When it senses your battery is fully charged, it turns the charger off. It then monitors the state of charge in your battery. And when it feels the charge is below it's set point, it turns itself back on until it senses the battery is fully charged. It use of electricity is super minimal when it's not charging. The beauty is you don't have to remember to hook it back up when you want to use your bike. 11.5 years is pretty good for any type of battery. My best was a little over 6 years. Best I ever got out of a Harley brand new battery was a hair over 2 years. I'm sold on using battery tenders.,,,
 
To clear things up for you, the tender doesn't keep a constant charge going into your battery. When it senses your battery is fully charged, it turns the charger off. It then monitors the state of charge in your battery. And when it feels the charge is below it's set point, it turns itself back on until it senses the battery is fully charged.
True, they are not continously giving an absorbtion or bulk charge, but after that, it will depend on the algorithm.

Most will continue to give a float charge of somewhere between 13.2 to 13.6 vt (depends on the brand and if it has temperature compensation)...this is done at a very low amperage, so it should not be stressful to the battery. Only a few brands actually turn off and monitor, then begin charging once the voltage drops below the set point. I think Pulse Tech and Clore Pro-Logix are two that do this.
 
Back
Top Bottom