Solara has developed the DCsolar OBD-2 battery charger. This is used for trickle-charging the battery and thus prevents self-charging during longer downtimes. The solar module measures 35 x 25 centimetres, has an output of 13 Wp and is installed on or behind the windscreen using suction cups. It can be connected to the standardised OBD 2 connection in the vehicle without specialist knowledge. The integrated charge controller prevents the battery from overcharging. The monocrystalline high-tech solar cells generate solar power even in low light. Price: from 79.90 euros.