Yes, solar car battery chargers do work, but their effectiveness depends on a few factors, including the quality of the charger, the size and condition of the battery, and the amount of sunlight available. That will depend on a number of factors, including budget, type of use (such as maintaining a charge versus recharging a depleted battery), the size of the car battery, and the. Theoretically, it is possible to overcharge a car battery with a solar charger if the charger does not have a built-in charge controller or overcharge protection. The majority of good. Think about what needs you have for your car. If you just want to keep it topped up then a simple trickle charger with a low wattage should be fine. If you have a car with a very large. If you're wanting to use a solar battery charger the first thing to remember is to turn your engine off before plugging the solar car battery charger in. If you're connecting your.