Smart Battery Charger, Mroinge 5.5A 6V/12V Automatic Battery Charger/Maintainer for Cars, Motorcycles, SUVs, Trucks and More, Suitable for Charging Lead-Acid & Lithium (LiFePO4) Batteries

I used this to maintain the battery on a motorcycle over the winter in temperatures as low a zero degrees Fahrenheit. It was much easier than removing the battery and bringing it in the house to prevent discharging and battery damage over the winter. It was easy to install and versatile. It works with both lithium and lead acid batteries.

Edit: It's been 3 years since I bought this and it's still going strong. I've used it for mostly AGM battries and never had an issue over the years. I switched to Lifepo4 for my main system this year so this charger has been on 24/7 for the past 8 months (not counting random power outages) keeping my 12v emergency lights, 100Ah battery alive and well. It's a great battery maintainer for standard 100Ah deep cycle AGMs and a solid charger for small lead acid battries. Increasing rating from 4 to 5 stars. Best value for money in my opinion. Oct 2017: Been using it for a couple months and it hasn't failed. When I first fired it up it got really hot while fast charging and I was worried but it has not warped or shown signs of heat damage. It's used almost every day to recharge a small bank off generator power. I was skeptical about buying something with so little reviews but my gamble paid off.

When my emergency backup generator didn't start during a recent power outage, I discovered the starter battery was dead, most likely of old age. I purchased and installed a new 12v battery and monitored its voltage. When the generator ran it's weekly 20 minute exercise cycle the voltage would increase to about 13.6v as it was being "charged" by the generator. Overnight (with temperatures dropping near freezing) the voltage dropped under 12, which isn't a good thing for trying to maintain a healthy battery. So I needed to come up with a better solution to keeping the battery topped-off, than the once-a-week boost from the generator. I settled on this unit because of it's variety of battery and charge settings, including ability to charge a lithium-ion battery which I have in my RV, and it's "smart" technology that I've learned is very important after ruining many batteries due to my negligence in maintaining properly. Loved that it came with optional connecting types and 'quick-connect' plug. TIP: set the battery type/charging mode after plugging unit in, but before connecting to battery. Just as the manual explains, the battery voltage reached and remained around 14.3v for a couple days (absorption stage) and has since been holding around 13.4v in the float stage. I may or may not leave the charger plugged in full-time as I monitor how well it will hold a full charge with a once-a-week charge from the generator during the summer when it is hotter and the battery looses less voltage overnight. EDIT (11/21/2025): Charger and battery still working great.

Great little charger. I keep this in the camper and use it to charge the camper batteries in a pinch.

Working good on my Harley

I purchased this a few years ago and it’s still working great! Simple design

In the beginning, I was a little bit confused for the battery connection wire doesn't come with fused but soon I realized the protective mechanism has already included in the main body of the charger, so it's fine. Now let's get to the good point - Because I have multiple bikes to charge - 1. The wire length is well designed, some other chargers are very bad at the length despite how well they advertised, but you are putting yourself into a corner where the AC source is over 3 feet far from your bike and you're about to return the product. I've got another charger with ONE feet length of the connection cable... 2. You can hang the charger, in somewhere you can see the status, which is an appreciated feature. 3. Last - excellent price, unlike over-sophisticated design or over-priced competitors, this charger is doing it right. I'll highly recommend this to my friends.

Excellent charger for the price works on many different types of batteries highly recommend. I will probably for just more

I have no issue with this charger, it works every time I plug it , it is easy to use and not finicky. plug it and let it charge your battery, no surprises.

الكهرباء 110v 👍🤨

I wanted a small auto battery charger I could throw in my tool box on my truck, this unit was small enough and it charges at the perfect rate to not boil a battery dry. I was impressed with its ability to bring an almost dead deep cycle battery back to a usable state overnight. For such a small unit it has a lot of automatic features that you would expect in a more expensive charger.

its small and great for a backup or tender charger

Not charging or charging so slowly that the battery is useless. It may be an okay charger to use at home to top up a car or bike battery but using it in off-grid setting with a gas generator is pointless. At 5.5A and 12V it takes about 10 hours to charge my 50Ah LiFePo4 battery. And non detachable cables that tangle up make it a frustrating device. Update Oct 2025 After using it a few times this fall, it looks like it's not charging at all. Even worse it reports the battery is fully charged after a short while. I do not recommend this charger.