as Teslinhiker points out, if the panel puts out the advertised 7 Watts.... divide by 12v and you get about .6A or 600mA...it would probably work as a float charger, but wouldn't be that practical for a 12v auto bank... you might take a look at the Powerfilm line for a flexible higher output panel

http://www.powerfilmsolar.com/products/portable-remote