5-Star Review:

⭐⭐⭐⭐⭐
Best Solar Battery Maintainer I’ve Ever Used – Truly Set It and Forget It!

I picked up this SUNER POWER 12V solar charger maintainer for my car battery here in Pennsylvania, and it has been outstanding. The plug-and-play setup was ridiculously easy — multiple connectors included, suction cups for quick mounting, and it started charging the moment I hooked it up. No complicated wiring or settings required.

The Ultra-Smart MPPT technology really delivers. Even on our cloudy and rainy days it keeps producing power, and it charges year-round without any issues. The 3-stage charging (Bulk, Absorption, Float) is smart — it tops the batteries off perfectly and then switches to maintenance mode so there’s zero risk of overcharging. My batteries have stayed at full voltage for months now with basically no effort on my part.

Tips I’ve learned for maximum effectiveness:

• I mounted mine south-facing with a slight tilt (around 35-45 degrees) and it gets great sun exposure. I wipe it clean every couple of weeks to keep the high-efficiency solar cells performing at their best.

• Connecting directly to the battery terminals gives the strongest charge. I leave it on my boat and RV all season — rain, snow, or shine — and it just works.

• For winter storage or vehicles that sit a lot, this thing is perfect. It automatically stops when the battery is full and resumes when needed. True maintenance-free operation.

How I test it with my multimeter (super easy): I check it every few weeks to confirm it’s working great. Set my multimeter to DC Volts and measure across the battery terminals — a healthy battery sits at 12.6–12.8V when fully charged. After the maintainer has been on for a bit in the sun, I see it climb and then stabilize nicely in the 13.2–13.8V range on float.

For current, I switch to DC Amps (10A setting), put the meter in-line on the negative side, and in good sunlight I usually see 0.2+ amps flowing in. Even on overcast days I still get a useful trickle. If you’re getting near zero in bright sun, just double-check your connections and panel angle.

This maintainer works with everything — flooded, AGM, gel, and LiFePO4 batteries. The build quality is solid, the safety protections are comprehensive, and it’s survived everything Pennsylvania weather has thrown at it so far.

If you hate dealing with dead batteries or constantly dragging out a charger, get this. It’s been one of the smartest and most useful purchases I’ve made for my vehicle. Worth every penny — highly recommended!

I have a late

model 5th gen 4Runner, purchased new. It isn't driven very often: after two years, it has amassed a whopping 3000 miles :) Great vehicle for me, but unfortunately, the telematics on this vehicle (SOS button, auto dial in the event of a serious crash, etc.) pre-dispose it to parasitic battery drain. This is a common problem for these vehicles if driven infrequently, a Toyota problem; my 15 yr old Ford P/U has similar telematic features but cranks without fail, even though it gets the same intermittent use.

After replacing the battery twice on a virtually new car, I tried this solar charger. I've had it going on three months now. I leave it connected to the terminals and disconnect it quickly, using the quick disconnect lead included by the manufacturer. It stores easily in the seat pocket behind the driver seat. Compact, weatherproof and durable with nothing to switch on/off, it comes with an led indicator to show what it's doing once connected.

Blinking green shows 'ready' and blinking red indicates current is flowing to the battery. Circuitry prevents over charging. As simple as that to use.

I monitor the charging performance and battery state using an Ancel BM300 Bluetooth Battery Monitor ($35 on Amazon) which sends info to my cell phone at designated intervals or on demand. The battery is always topped off and ready to go. Problem solved.

The Amazon listing shows suction cups that permit sticking the panel to a suitable surface while in use. I didn't receive suction cups with my charger (an omission, I believe) but that's not a problem. I affixed four coin-sized magnets to the reverse side which secures it to the hood or roof when in my driveway. If using it in a less secure location, I would keep it inside the vehicle, flat on the dash. The harness has a generous length, making routing to different spots simple.

Would I purchase this again? Yes. 5 stars for simplicity, performance and ease of use.

*** update*** one of my best purchases! Changed it from four stars to five because I had not had it very long. This thing is fantastic! I have an older 2000 4 Runner where if I don't have a stronger battery like an AMD or EFG the battery is dead in three days without driving. There's a constant known drain on these Toyota's. The stronger batteries last about three weeks before they start to slowly disintegrate in charging. After having to get a second EFG battery the mechanic down the street told me to get a solar charger. I read lots of reviews and this is the one that I decided on. I had my portable jumper with me today prepared for the battery to not be working because I literally have not driven it in at least three months! I thought no way!?? But yes, it started up like a perfect brand new battery. I brought the charger on my errands because I thought maybe when I stopped it will discharge but no, it started right up again! I love this thing! Remember if you're gonna let your car sit to have a full tank of gas for the Health of the tank*****I like that the size is not overly obtrusive, and it's got plenty of length in the cords which is a huge plus for me as it doesn't limit where and how I decide to connect the solar panel to my battery. That being said, I have an older 2000 Toyota 4Runner and it's one of the models that does not work with the cigarette lighter which my sister said to use. Her husband used to have a collection of cars including Ferraris and $400,000 Porsches etc. all on trickle chargers but unfortunately I tried that mode and it will only connect while the engine is running which defeats the purpose! The small clamps are covered in cheap plastic and just barely fit around my battery terminals but they seem to work and send a signal. The third option doesn't look like it goes with my traditional type of (EFB) battery even if I unscrew the bolts and put it underneath. I'm not sure so I'm going to have to ask my mechanic because the kind that could just attach to your terminals without clamps. I could leave on and just disconnect and connect at will. The photos show a different type of battery for that straight wire connection so it looks like I am stuck with the clamps. I bought a 4 pack of round Dyi...?(you can find it by searching rubber coated magnets ) that won't rust or hurt my car and actually attach strongly to car. I read a lot of reviews on a lot of different magnets and many of these magnets won't even stick to stainless steel. You can't really attach them to this all on their own so what I did was I glued two of the magnets that are the exact size of the suction cups and added them to one end/side of the back of the board. This magnetized the board very strongly to the top of my roof and I was able to put up an angle on my roof rack. (See pictures ) It's not going anywhere! I don't know if I would want to attach it to my window as I'm not a big believer in suction cups holding in extreme circumstances like the magnets would . I have every confidence that these magnets will work through my car cover when I put that on. I sure wish I could've used the cigarette lighter but cannot so don't expect it to necessarily work on your car or think that it's defective because it doesn't light up on your model. It's charging right now so I will get back in a week or two to see if it stays fully charged. I know some people are recommending that you buy a battery status contraption for another 40+ dollars that if you get Bluetooth and you stand within 30 feet of your car it will give you the status of your battery health. I don't know if I need to go to that extreme. It's for a car that I don't drive that often, either of them that often, so I always have to worry about the battery. I sure hope for the price that this last for a while and from some reviews it seems to kind of be hit or miss so check the status light fairly frequently.

So, I have the 12W/12V one. First, it comes with plenty of connection styles. So that is a plus. I have a battery on my utility trailer which runs the electric jack. I use this so I do not have to hook it to truck all the time. Love it. It charged the battery from dead dead and it now keeps it sustained. I did not permanently mount it so I can take it down easily

Now the bad. The battery has the SAE connector for ease of connections. (to avoid reading the rest I will put a note here and tell you the connectors on the solar panel wires are reversed.. read on if you need an explanation)... As does this solar charger. So, there is no way to hook it up wrong. And the battery is hooked up correctly (red to positive/black to ground) . Having said that I hooked the solar panel (supplied with the panel) SAE connector and the LED light on the solar panel LED blinked weird. So I looked up the code on the Solar panel instructions and it says it was reverse polarity. Again, I can not hook it up wrong. So, I had to use the alligator clips (and reverse the clips on battery) to get it to charge. Works great now but I cannot use the SAE connectors as it is backwards. Weird. Minor inconvenience but it should be mentioned.

Works perfectly- easy set up. Charges sitting on dash. Jump started totally dead. After getting it running, put charger on. Plugged into 12V in switched outlet. Went to 14+ volts & has stayed there. Ordered another for my boat - will return it as I reordered the higher end model. This is still awesome!

Great performance! Does what it supposed to and keeps my motorcycle charged and my electric reel motor !

Think I might get 2 more!

Don't freak if the lights stop blinking it just means there is not enough light it will resume in the morning!

husband loves it works great this is the second one i bought he forgot to unplug the first after several months of use and broke so had to reorder asap.

The power is wired backwards. You can't measure the voltage open circuit but you can check with an amp-meter the power flowing from the panel. Glad I checked it before putting it to use. I did show a small current flow but in the wrong direction, it was discharging the battery. I could have cut the wires and reversed the leads to see how it performed but refused to do that and void the return or warranty if it did not work well. I sent it back and bought a more powerful panel at a much cheaper price. DO NOT BUY unless you're willing to cut and splice wires to make it work.

IMPORTANT UPDATE::: After the above review and a one star rating, the vendor reached out to me to make things right. They supplied me with a new panel that works great. It was late in the day and had heavy overcast but I thought I would try it out anyway, not really expecting anything until I could try it in the next afternoon. I was surprised that even though it looked like it could rain at any minute the panel performed well under the stated conditions. This is the only panel I could find that had a built in MPPT controller built in. The MPPT is important to provide maximum charge under all lighting conditions. I believe that a panel without an MPPT controller would not have worked as well especially under the very adverse conditions that I tested this panel at.

I've had it for 2 years and its saved dead batterys and brought many things back to life lol I want another its been sitting in the snow and rain and sun and still works great

Using to keep our generator battery charged. Working well as needing to run the generator at the moment.

We bought this for our boat batteries. Works as it should, small compact unit fits where we wanted to put it.

Bateau sans « shorepower ». Super 👍👍👍

Even though the flashing green lights indicates it’s charging I didn’t verify output when installed. I went to start my boat the the battery was dead. After putting a meter on it was reading -5 to + 6 resulting in draining my battery. Unfortunately I can’t return.