ECO-WORTHY 10W 12V Solar Trickle Charger Car Battery Maintainer, Portable Solar Panel Power Backup Kit with Alligator Clip Adapter for Car RV Boat Automobile Motorcycle

I got this as I've had a couple of batteries gradually die due to lack of use - I drive a classic car and as it's only used a couple of times a week, the battery drains over time.I fitted a 12v cigar lighter socket in the grove box and wired it directly to a circuit which stays live with the ignition off. I put a fuse in line, though given the tiny current, it's unlikely to be needed.At first it didn't seem to be having much effect, as although my multimeter showed a good output from the panel, the red LED in the charger seemed to be draining the battery once the sun set.Emboldened by other comments on here, I disassembled the charger socket (it unscrews easily), and simply snipped off the LED which is soldered across the metal prongs of the charger. Reassembled and refitted, it's a five minute job if that.After another day in the sunshine, and another night in the dark, I tried the car again. The battery was fully charged, and the starter motor turned over faster than ever!I now leave the panel plugged in whenever I'm parked up for more than a few hours, and the battery is in a much better condition as a result. It only takes a second to plug and unplug, and fits nicely in the map pocket on the back of the passenger seat. God knows why the charge sapping LED was included - but once removed, this is a great bit of kit.

Works well and stops the car battery from going flat even in winter.The only issue is the red led is very bright and is running from the battery in darkness so uses some of the electricity generated during the day.Perhaps it would be better without the light.

I've been using this for a while now, and part of me is a bit sceptical about how well it actually works, but another part of me thinks it's actually doing a reasonable job and I'm expecting too much from it.I got this as I do well under 4000 miles a year, and I have noticed that my stop-start system is very reluctant to work, which I put down to low battery charge. Sometimes I used to get into my car and I would get a "Low battery - Drive car" message, so clearly my car doesn't appreciate being sat around doing nothing.As I have no intention of driving around just to keep the car's battery happy, I bought myself a battery charger, but it's a nuisance to connect and disconnect, so I sought a better solution and came upon this.The panel itself is well-made and surprisingly sturdy, the solar panels being mounted onto a metal plate. I just leave mine on the dashboard when I'm not driving the car, and disconnect it and bung it in the passenger footwell when I am driving. I didn't fancy leaving sucker marks on my windscreen, though that might give the panel a better operating angle.One thing I don't like about this, is that the red LED on the 12v plug lights up at night, so there is clearly a power drain from this device when it's not supplying power to the car from the panel, but it's easy enough to unplug the 12v plug at night, though less convenient that it might be. I think left to its own devices, the panel is a definite net gain on battery voltage, particularly in summer.If you have a battery charge problem to solve, this might not be a complete solution, but it does help. I've not had my "Drive car" message come on for ages, and the stop-start system seems a little more inclined to kick in than it did previously.It's no substitute for a real battery charger, but then it doesn't claim to be. It's alright.

With my car located outside, this works really well. The car has an electrical fault somewhere and the newish battery quickly drains. This has solved the problem and I can start it, sometimes six weeks later, without issue. Suction pads great. It plugs in to the cigar lighter (car built 2000). Check if your car is compatible with this panel as there are two outcomes to charging from the solar panel due car technology moving forwards. See reviews or online.