Car Battery Trickle Charger & Maintainer 12Volt 8W Solar Panel Power Charger kit Portable Waterproof for Automotive RV Marine Boat Truck Motorcycle Trailer Tractor Powersports Snowmobile

I put this in an older 2005 car. You need a cigarette lighter that stays powered when the car is off to use the trickle‑charger plug. If yours doesn’t, it comes with battery clips and plenty of wire to hook it straight to the battery. Very easy to install. I own two — one for my ’99 F250 and one for my ’05 Cherokee — and both work great.

My husband purchased this for our older cars and truck recently. He doesn't use his truck every day, so he keeps it on the dashboard. It works really well, as our driveway is in a location which gets a bit of sun every day. He will move it from vehicle to vehicle, as he needs it and it has not failed to charge yet!

Works well, however does not have indicator to show if unit is charging.

Purchased this to keep the battery charged on my car trailer and so far no complaints.

I bought this to maintain my Ford pickup with 2 batteries between uses. I hooked it up to my Son-in-Laws Nissan pickup that had a battery down to less than 3 volts but was setting about 200' from the nearest power supply. After 3 days I checked and the battery is up to full power.This will take care of my needs and keeps me from running extension cords to hook up my commercial charger to maintain.

I got about 3.7W max power with the cell sitting flat on the driveway in Oct in Dallas around 2pm. I did not tilt it to get the optimum angle. Initially the power was about 1W higher but after 30-60 min in the sun the efficiency drops. The panel is rated for 8W if I can get 1/3 to 1/2 of that, I'm happy.I also put it in my van on the dash (again not angled toward the sun). The power dropped again (glass is blocking some of the light, see curves). I guess it could overcharge my battery (lead acid) since my parasitic drain is about 70mA and the cell voltage drops to 15.3V at that current (orange curve), but I doubt it since my new van sometimes will charge at 15.5V for 30-60min, then down to 14.4V for most for the time and sometimes as low as 12-13V. Unlike my older cars where lead acid charging was always around 14.4V. When the cell was on the driveway (blue curve) the cell resistance was about 12ohms in the 100mA to 200mA range if that helps.

These have to be in exactly the right position to work, which means you have to have a meter to check and move it with the sun. I had a 4watt, and it worked flawlessly. I returned two of these, and bought another 4w. However, I was only credited for one, even though two were in the return box.Buy at your own risk, and return with even more risk.

Pros:+purchased the 8 watt panel and it had decent output. It was able to charge my battery on my spare car and keep it topped off+Plenty of cable for my use even when the battery isn't IN my car to be charged. I was able to place the panel on my carport roof and it still could reach my battery on the ground with cable to spare.Cons:-this is a big one. After less than a month in the sun the plastic housing popped open. I don't think it's waterproof at this point. Upon inspection it popped open because the plastic housing has warped and curved preventing it from being able to stay together. If it can't handle being in the sun then I think a redesign is in order. I can't exactly keep my panel out of the sun to prolong the lifespan of the materials.-the connector fills with water when it rains. The panel was on my daily driver and the connector between the panel and the clips filled with water. I shook it out and everything still works but I can see this becoming an issue after a while.All things considered I'm gonna have to say this isn't worth the money. If it can't handle being in the sun then it's of no real use to anyone. What good is a solar panel that can't handle sunlight?