Yes, it seems they all work well as conditioners, and many have AGM selectors. The only real difference
seems to be the available charging amps which really only affects the speed at which a discharged battery
will charge.

 

As Randy says, most, if not all, are AGM capable. I can tell you that if you have the brand Battery Tender and while not connected to the battery, it flashes quickly, its AGM capable, it has an auto detect. The use of these devices has more than just maintaining the battery condition, ...it will help the terminals stay clean of corrosion for better alternator function and start up reliability (the batteries real purpose).

The recharge of these units is a trickle charge in mill-amps, too much of a charge and it can burn out a cell because it cycles on and off. Initially, depending on the depletion of the battery, the charge can take upwards of 12 hrs before it goes into a cyclic charge, ...any longer could mean you have a going bad or bad battery. Inspect it for swelling and/or corrosion and take it to a parts store for a test. A corrosion free set of leads is important or these units are worthless. You'll be taxing the battery as well as the alternator and starter which can ruin all 3 and in these cars, create ghost problems.

There are direct terminal connectors for voltage readings, ...I'm not sure how reliable are the ones that plug into the cigarette lighter constant hot lead? If using a either one, I suggest getting a reading with a multi-meter directly off the battery as well to see if there is any difference ...and if so, there is a good possibility the unit isn't good for this (especially the plug in) or there is corrosion on or a poor circuit.

 

Just double checking, what model CTEK charger is the best to buy for an 2018 AGM battery?

 

The year of the battery is irrelevant, AGM or standard lead acid is the know. Go to CTEK's site and check out what they have and for what type. As I say in post #22, Battery Tender covers both in one product.

 

Thank you

 

https://www.ctek.com/uk/education/ca...tery%20charger.

https://baintech.com.au/product/ctek...ttery-charger/

Apparently all CTEKs can deal with AGM batteries. Not sure, if they recognize the AGM themselves, of if a different program needs to be selected - the manual will hopefully tell.

I have 3 CTEK chargers: 5A, 7A, 15A. I recommend the 7A for Jags. The second link is for such a 7A charger and it also mentions the AGM in the description, which is why I posted that link. The link should not suggest to buy it there. Check for specials both on the internet and in shops and compare.