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

Great little 'trickle' charger, for any vehicles that have to sit around (in storage, etc.), or in challenging weather!! I have one, on my RV, stored in a chilly climate, and it keeps my battery in top condition! Bought another one, to use here at home, with another 'weekend' car, that has some minor issues with a slight battery drain. It is also very very adaptable, because it works with older, and newer battery types, and charges at appropriate intervals in order to not damage those newer type batteries.

I have a truck that mostly sits in the garage. Every time I need to back it out of the garage, the battery is dead. I know that just sitting isn't good for batteries, not to mention this battery is several years old. Now keep in mind, this is a large amp battery for a SUV, which was so dead, a turn of the key and I didn't even get lights on the dash. I stuck this little charger on it and it took a day and a half, but it charged completely. Ok, now I'm beginning to get a tad impressed. I have two of those old type chargers, you know the ones that after a while you can hear the acid boiling inside the battery, and the battery is getting really hot... you know the chargers that tell you not to leave it on your battery for any extended period of time as this might (will) damage the battery (possibly even start a fire). Well... no more. I'm a total convert now to using smart chargers, and this one seems especially good. I really hope I don't find some little something that breaks 6 months from now, cause I really like this charger! It seems very well designed and made and most of all, it works great. The only negative I can find, it has a single button to select one of several charging modes, and LED's to indicate which option you have chosen, and those LED's are pretty much self explanatory, as well as an advanced mode where you have to push and hold the single button to enter advanced charging mode. For example, if your battery is so bad, the charger cannot detect there is even a battery hooked up, you can tell it to go ahead and start charging anyway which is a really nice feature. As another reviewer mentioned, when you need to use some of the more advanced functions, if you've lost the booklet, well... good luck. The multi-language booklet briefly explains all of the options, what the LED's mean, and that's pretty much it, verbose it isn't.. It comes in a really nice packaging, like you're really getting something ( and you are), the unit itself seems well made and thought out, you would think a bit more of an effort would have been put into the manual. But, perhaps the product speaks for itself... and it does. And, after all most users will hook it up to their 12 volt car/boat/motorcyle battery, plug it in, select the regular 12v battery option, and that's all most will ever need. Once the battery is charged completely, the charger senses that, and switches automatically to just maintaining the battery. If you loose power while charging (or maintaining), this charger just picks up right where it left off, so there is no worries about pushing buttons or selecting modes, it knows what you were doing before, and starts right back up with doing it again. Am I glad I got it: Yes Would I buy it again: Yes.

Takes a while to fully charge my truck battery, about 3 days!! But it was easy to set up and understand. It's continued to work over the years I've had it and overall it does it's job and really does recharge the battery fully! Very nice little affordable product. Thank you!

I've had products that came with rather poor instructions. This device came with NO INSTRUCTIONS AT ALL! That said, once I found instructions elsewhere, it seems to work well and is reasonably easy to use. My car battery, in the car, went from pulsing red to solid green overnight. Hopefully it will prolong the life of my battery. If not I'll come back with an update.

I will try to be as honest as possible because I depend on other people's reviews and feel I want to help the best I can: Item arrived just as described. This appears to be a well-made and quality item. Every Winter I must totally disconnect my Riding Mower Battery to keep the Engine clock on the mower from wearing it down. In the spring I must hook the battery back up, cross my fingers and hope the battery has enough charge to fire the engine up. I decided enough is enough and invested into this little gizmo. WOW am I impressed. I got the 1 Amp because I do not need it for charging dead batteries but just to maintain the mower battery over the winter time. I also picked this one for the mower because it plugs in directly. I did not wish to have a smaller cord run across my shop floor all winter while I walk on it. SO, I got a 15' extension 12/3 Heavy Duty cord to run to the mower. I plugged this item into the cord and hung it on the back of my Zero Turn mower. Then I ran the battery clips to the battery posts. This way I'm walking on a thick heavy duty extension cord all winter, which will be fine. I can even roll my wheelbarrow on it without incident. My mower had been sitting about one month unused when I decided to purchase this item. Once plugged in, it did everything exactly as expected from me watching You-Tube videos and such. I saw it was charging and left it alone for a few hours. I came back and had a solid Green light on meaning it is now just maintaining. I have checked it daily and it's working great so far. Now I will not need to disconnect my mower battery ever again AND the battery is fully charged when I'm ready to start it up again this spring. I will NOT be using this item during the spring or summer months because I run my mower once or twice per week as a normal. I Recommend. Good Luck.

Haven't used it but e, cited to have and the quality looks far away better then the normal battery tender

Best trickle charger on tge market. Saved my S$$$piral AGM starter battery for one year on trickle. 100% CCA still available for my rebuilt vehicle !!! Worth every č̣ent !!!

Esto es una maravilla, me encanto y funciona perfecto, me rescato mi bateria y le da mantenimiento perfecto, gran producto. Ahora me arrepiento de no comprar una de mayor capacidad. Pero por lo pronto está esta perfecto

The Genius 1 looks and feels really solid. It doesn't look çheapo' like those from China. Yet to use as I am unable to plug it to a AC 230v wall socket. ( lives in a high rise apartment ) Hopping it will work

شحن البطاريات خاصة للدراجة سواء 6 فولت أو 12 فولت، ولا ننسى التيار الخاص للبطاريات يجب أن يكون أقول من 30 أمبير، فلو رغب بأعلى ينصح شراء شاحن نفس الموديل ولكن بتيار أعلى 5 أمبير أو أعلى ، ولك الخيار