Review on 🔆 Topsolar 20W 12V Solar Panel Trickle Charger - Portable Solar Battery Maintainer for Car, Motorcycle, Boat, Marine RV - Includes Cigarette Lighter Plug & Alligator Clip for Easy Charging by Kham Fisk

I used it on my regular lead acid car battery once and it died on me. For both vehicles. Luckily it was in my parking lot. I had to start with another spare battery. I think it would be good to charge a small cell phone battery? I wouldn't try that again on my car. Maybe I got a defective one, like someone else's review. Maybe it got hot because I kept it indoors on the dash but with the window ajar.