5W 12V Solar Battery Trickle Charger Maintiner, Built-in Smart MPPT Charge Cntroller, Waterproof 5 Watt 12 Volt Solar Panel Charging Kits for Car Auto Boat Marine RV Trailer Motorcycle, etc

Reliable fast charger but not ideal for Lithium Iron Phosphate batteries
 I am reviewing the 15 watt MPPT Solar Powered Trickle Charger from Gropow. I have a 2015 Tahoe that I infrequently drive and because it has so many circuits that use battery power even though the engine is off, there have been times when the Tahoe would not start because the battery discharged too much.An external charging source like this would allow me the convenience of not having to run an electrical cord to power a battery charger.Three different means of attaching the battery to the trickle charger are available. Each method is easily attached to the charge cord that comes off the charger with a Plug and Play SAE connection.I could not use the cigarette lighter adapter method because once you turn off the engine on the 2015 Tahoe and open the driver’s side door, electricity stops flowing to the cigarette lighter receptacle. As a result, even if the solar charger is working and one uses this method to charge the battery, no current would flow to the battery.Therefore I chose the alligator clip method. Both the negative and positive clips are fully insulated with a plastic covering which would help to prevent accidental shorts. The third method is for a custom installation to the battery. It is a SAE connection to bare wires.The durable plastic covering of the charger is well made and since it is plastic, it cannot scratch the surface of a vehicle. If you want to mount the charger to the window of the vehicle, four suction cups are provided. Glass covers the solar array.The charger worked flawlessly and once the battery was fully charged, the green LED remains on without blinking. The next morning the LED was blinking red indicating the battery had dischargedsomewhat overnight. However, within a few minutes in full sun, the LED was solid green again.Since the description states that this charger also charges Lithium batteries, I decided to see howit did to top off my 12 volt 50AH Lithium Iron Phosphate battery. I discharged this battery to 13.2 volts andconnected it to see what would happen. It took the Lithium battery up to 13.3 volts but no higher. However, when I connected the battery to a 75 watt solar panel and a MPPT charge controller that is programed to charge a Lithium Iron Phosphate battery, it took the charge all the way to 14.4volts. This means that this charger will not fully charge a Lithium Iron Phosphate battery even though it indicates it does. Otherwise it is a fast reliable charger for all other types of batteries.The video shows the Gropow charger connected to a 50AH Lithium Iron Phosphate battery charging the battery to 13.3 volts as indicated by the flashing LED light. The first photo shows the battery charging at 2.7 amps at 13.3 volts using a different MPPT charge controller that is programed to charge Lithium batteries. The next photo shows that this charge controller took the Lithium Iron Phosphate battery to its true full charge of 14.4 volts. The next photo shows the solid green light on the Gropow charger indicating that the battery is fully charged at 13.3 volts. The next photo shows a 75 watt solar panel connected to the MPPT controller and battery. Sorry, these photos appeared in a different order than I posted for the review so I wrote an explanation for each photo.

Don’t Waste Your Time or Money
Purchased as an on-board charger for a vehicle that sits a lot. After about six months it has zero voltage output in full sun, the green LED flashes “okay” but there is no output. It will not move the needle on my multimeter. I have other brands of solar chargers that are gong on five years old and still kick out the voltage to maintain a full charge.chineseum junk. Caveat Emptor!

The cigarette lighter attachment works better for me than connecting directly to the battery.
Not too keen on the suction cup setup. I’d prefer that they were permanently attached and not adjustable. But once it’s setup it’s been charging perfectly.

I wish I had this years ago!
I bought this solar charger because I live in my van (down by the river 😭) and as a result, my car battery dies often because I use it to charge my phone, laptop, lights, etc. so my current lifestyle is a HUGE burden on my battery. I got this solar charger and I am not kidding when I tell you that I noticed a difference on the very first day! The van starts right up, the dashboard lights are brighter and the power windows actually go up and down faster! Of course, I live in Southern California and it’s the middle of summer so I don’t know how it would work in places that don’t get as much sun but it works incredibly well here. If I had this a couple years ago, it would’ve saved me a dozen or so jumps. Now I keep it permanently on my dash and plugged into the cigarette lighter. The only advice I can give is that it slides around on my dash when driving so I bought a rubber dish mat at the dollar store to put underneath and it solved the problem. Money well spent!