OptiMate have released a new solar kit designed to keep batteries topped up. Perfect for bikes kept in sheds or outside under covers, the OptiMate adapts based on the amount of sun and can even keep batteries topped up on cloudy days. The Solar Kits are safe for use with all lead acid and gel-based 12v batteries and are pre-drilled for mounting on walls and roofs. There are five kits available starting from £104.99. There is a three-year warranty.