AGM Battery charging

[E150GT]

I recently bought a new X2 Power group 35 battery in the mazda. The OE battery only had 125 CCA according to the tester and it barely started my car.
I've had a few days off so I have been messing with it. I took a measurement of the battery yesterday around noon. It was 12.5v. I could see that as I had started it the night before just to move it into the garage. Later in the evening I went to clean the interior but I decided to hook up the charger. Its a NOCO Genius G3500. I took a voltage reading before hooking up the charger and it was 12.35V. Seemed kind of odd but I hooked up the charger and got to cleaning the interior. I checked after cleaning and it turns out if the interior lights are on the charger won't really do much. It was still flashing the 25% light and the voltage was around 12.5v. As soon as I closed the doors and the dome lights went out. The charger voltage started climbing. It rose up to 14.6V until the charger started to flash green 100%. It dropped down to 13.something and I left it over night. I checked just a moment ago and the green 100% light is solid. I turned on the voltmeter and its still pumping out 14.4V. Seems kind of odd. Should this be the case? I don't want to ruin the battery with a faulty charger.


20181125_120728 by JOHN, on Flickr


20181125_120604 by JOHN, on Flickr

 

[StevieC]

I had this very charger when I put the AGM in my Journey and it would never fully charge the AGM despite the charger showing full. I then purchased the Oddesey AGM charger and them after that a Ctek and had 0 issues there forward with charging the AGM. IMO those NOCO genius chargers aren't good for AGM's.

Did fine on a lead acid battery though.

 

[Onetor]

Beautiful K-9's by the way! Other pics are publicly available FYI.

 

[Pelican]

Originally Posted by E150GT
I recently bought a new X2 Power group 35 battery in the mazda. The OE battery only had 125 CCA according to the tester and it barely started my car.
I've had a few days off so I have been messing with it. I took a measurement of the battery yesterday around noon. It was 12.5v. I could see that as I had started it the night before just to move it into the garage. Later in the evening I went to clean the interior but I decided to hook up the charger. Its a NOCO Genius G3500. I took a voltage reading before hooking up the charger and it was 12.35V. Seemed kind of odd but I hooked up the charger and got to cleaning the interior. I checked after cleaning and it turns out if the interior lights are on the charger won't really do much. It was still flashing the 25% light and the voltage was around 12.5v. As soon as I closed the doors and the dome lights went out. The charger voltage started climbing. It rose up to 14.6V until the charger started to flash green 100%. It dropped down to 13.something and I left it over night. I checked just a moment ago and the green 100% light is solid. I turned on the voltmeter and its still pumping out 14.4V. Seems kind of odd. Should this be the case? I don't want to ruin the battery with a faulty charger.
20181125_120728 by JOHN, on Flickr
20181125_120604 by JOHN, on Flickr


There is a world of difference between the NOCO Genius and any CTek, which it copied, mainly in the quality of the internals. If you know of someone with a CTek try it or buy one you won't regret it.

 

[Bluestream]

Remember to take off the surface charge before checking voltage

 

[E150GT]

Sucks to hear the NOCO are crap. I don't need another charger. I should have checked out the reviews.

 

[Greggy_D]

I had a NOCO. Used it around 15 times over 5 years. I went to use it last month......nothing. Won't even power on.

 

[HowAboutThis]

Yeah, many people with AGMs don't use the proper chargers. It's great because you can buy refurb batteries that are fine, but people returned, because they don't know how to charge AGMs.

 

[Mainia]

My new Hyundai Kona turbo AWD comes factory with a AGM and researching chargers I found NOCO are not the most reliable, plus most are very low amp charging. I bought a MinnKota brick since it can charge 10 amps and has an AGM setting. When I need a charger 5 amps just doesn't do it . I bought their Precision version since it has the stabilize mode for lead acid batteries.

https://www.amazon.com/MINN-KOTA-18...ywords=minnkota+10+amp+charger&psc=1
.

 

[Wolf359]

I like this cheap $18 battery charger, also does AGM. Not sure if your old one does. Normally I charge it by disconnecting it from the car. Chargers can go up to 15 volts when charging the battery, normally in my car, the alternator goes up to 14.5 volts. A fully charged battery should be about 12.73 volts at 70 degrees after it's been sitting a while with no load connected. By charging it with the battery connected, you're also powering other items that draw power from the battery and hence you're not fully charging it. Doesn't really matter that much, but just an FYI.

https://www.amazon.com/Schumacher-SC1279-12V-Rapid-Charger/dp/B07DM22XTN

 

[E150GT]

Originally Posted by Onetor
Beautiful K-9's by the way! Other pics are publicly available FYI.

Thanks. That's Cooper. The luckiest/unluckiest dog in the world

 

[E150GT]

I'll probably get the Ctek MXS05 charger. Shouldn't need anything bigger. The largest batteries in my fleet are group 65 and 79.