I have always had good luck with a BatteryMINDer such as this one:
Probably more than you need, and I'm sure there are cheaper versions that are just as good. I also own a NOCO Genius which is cheaper and probably just as good.
The BatteryMINDer is not waterproof or rainproof, so be careful. Found that out the hard way.
But for batteries, I only use two types. For some things, I will use the old style lead-acid wet cell. But for a boat, my tractor, and all my off-road equipment, I will only use an Odyssey AGM.
AGM, because its stupid to replace terminals and battery boxes every so often due to corrosion, and Odyssey, because that seems to be the best brand out there now.
I hear that they make batteries for other companies for maybe a lower price. I have heard that the top of the line NAPA AGM is an Odyssey, but not sure. And maybe one of the Diehards.
Of course they are very expensive, but if you take care of them, they will usually outlast a regular battery 3 or 4 to one. And they don't spill, leak, or emit corrosive vapors.
I used to have to work on my steel battery box in my F-250 almost every hunting season. I would clean it, paint it, and coat it with grease. And still it would rust out in a couple of seasons. I tend to drive my truck hard and fast through the swamps.
Put in a new box and filled it with an Odyssey about 6 years ago, and both are doing fine. Battery cranks good, and the box is rust free.
When I bought my new tractor, I was taking off covers and looking things over after I had had it about two weeks. Noticed there was already rust in the battery box.
Tractors have no suspension and bounce around a lot driving over plowed fields and things.
Immediately ordered an Odyssey for it, and gave the brand new wet cell to my friend for his big riding mower. My tractor is doing fine on that battery, and he just bought a new battery this mowing season to replace the one I gave him.
J.