NOCO GENIUS1: 1A 6V/12V Smart Battery Charger – Automatic Maintainer, Trickle Charger & Desulfator with Overcharge Protection & Temperature Compensation – For Lead-Acid & Lithium Batteries

Okay, I did NOT expect this little thing to work, but it did and might for you IF you have patience.My Grandfather who was MoAT (Mechanic of All Things) owned back in the day what I thought were REAL chargers, they were so big and heavy they had to be put on wheels and rolled around, they had giant switches that'd illuminate and while I'm probably purely imagining this they were plugged into 220-volt outlets. This thing fits in the palm of my hand, just as pictured, smaller than most mobile phones. "Huh," I said, "this should be comical."I hooked it up and, as others have said, figuring this thing out is NOT straight forward, the instruction manual is weak to say the least, the good news is, as I found, there are many intrepid experimenters who, like me, bought it on a whim and did some trial and error which it'd seem 99% of them got the thing to work to their needs, just like me hence, I'm taking the time to write this review. What this lacks in coherent features or instructions it makes up for it in the end by eventually (boy I mean eventually) getting the job done, for that honestly I'm giving it a generous five stars, because it did what I wanted it do against all odds, just like the Phil Collins song. ("Just take a look at my car now, 'cause it's finally starting here.")To get the to point, this took TWO WEEKS to charge a completely dead battery in a completely dead system. If it'll help anyone I own a 2000 Lexus RX300 that is, in fact, drinking age, if I could find a small ute-friendly bar to have a couple with me of which, in terms of trusty old friends, this boring beige over beige has been one of my best now with over 270,000 miles with no reason, per the Lexus dealer, to give up the ghost before 300,000. Toyota quality and then some with only wearables and maintenance needed BTW, the car has only had one issue, eating car batteries every four or so years. Being a cheap bastard and Lexus parts are pricy I've chosen battery over a slightly-off generator which brings us to the recent hullabaloo and the need to be the Noco Genius, though it'd prove not straightforward as I hoped.Hooking up the Noco Genius you get a slowly blinking light, like a heartbeat, that will tell you nothing really. Also there's a force-charge setting where you hold the button (there's only one button on the whole thing, this thing is basic) it supposedly will force a charge into a battery... this doesn't work, at all. After some digging it supposedly only does this if a battery is below some arbitrary limit which, my battery was completely dead, kaput, nada, force charge only made the 6V light go on which, apparently, is what others experienced. Point being, don't hold you breathe.I kept trying to charge the battery but it didn't budge, didn't budge, didn't budge, then I had a thought and said to myself "self, what if I unhook the battery, THEN charge it?" As in, is it because it's also hooked to my car hence current is going other places? Mind you, this thing is only one (1) amp, that's very little, if you're looking for a quick charger or something to charge and jump your car, this ain't it, have you seen the size of this thing? Ha no, no, but it will trickle, very slowly, a charge into your battery... if it's not hooked to the car.Listen, some people this may work when the battery is not hooked up and, in fact, I hooked my battery back up AFTER this thing actually worked and then hooked up the Noco to it and it did, in fact, go from red blinking to green, sooo, yeah, that happened. But I'm burying the lede here:The Noco charger worked for me but ONLY after it was hooked to the battery without being connected to the car. Total time to charge the battery not hooked to the car? About 36 hours. Great? Eh, there's a pandemic, I'm not really going out much so had time on my hands, not to mention my wife's car.In summation, IF you have even a completely dead battery or run down battery and IF you don't have to go anywhere in the next two days and IF you're comfortable unhooking the leads from your car to your battery so that it'll only be charging the battery itself this Noco Genius is, er, uh, genius! It really works! It works and for the cheap cheap cheap money its worth every penny. If this thing cost even 50% more I'd be taking down stars but this thing cost less than a steak dinner (back when I ate steak) so suffice to say it got my battery charged all the way up, hooked up to my car and after the computer was all "what the... ??? Was I in a coma" my car fired right up and ran, I even drove it around a bit.This would be a good thing to own for just-in-case as its just in case money. If you have any situation close to mine, get this trickle charger, if you need the big guns, well, open up your wallet and say ah. Luckily most of us, probably 99% of us, if your battery is run down, this will do the trick.Best of luck!

The NOCO GENIUS1 is a compact, reliable, and versatile battery charger that really delivers on performance. Despite its small size, it packs plenty of power and works flawlessly with both 6V and 12V batteries, including lead-acid and lithium. I love the smart charging features — the built-in thermal sensor adjusts automatically to prevent overcharging or undercharging, and the ability to revive deeply discharged batteries is a lifesaver. It’s super easy to use, safe to leave connected for maintenance, and compatible with just about anything from cars and motorcycles to lawn mowers and boats. If you want a dependable all-in-one charger and maintainer, this one’s hard to beat.

I recently picked up the NOCO Genius 1, and I have to say, this thing is a breath of fresh air. It was so easy to use, it reminded me of how things used to be, you plug it in, and it just works. And for what it costs, around $30, it's a real steal. You're getting a ton of value for a very fair price.Right out of the box, it was a breeze to get going. The instructions were clear, and I had my battery hooked up and charging in minutes. You don't have to be an expert to figure this one out. It just does its job, quietly and efficiently.If you're looking for a battery charger that's simple, reliable, and won't cost you an arm and a leg, this is it. It’s a great piece of equipment that handles the task without any fuss. Highly recommended.

Works as expected, easy to set mode or battery type. I use the charger/maintainer to keep my lawnmower battery charged, which is an AGM type. One feature you need to be aware of is the clamp connector is NOCO proprietary meaning non traditional so not compatible with Battery Tender and other brands that use that type. So if you have ring connector say on motorcycle or something else, the NOCO won’t connect to it, although you can buy adapter to connect. Overall I like the tender charger, for my use works perfect. Gave 4 stars only because of connector being non traditional.