SunCat: Solar Batteries Powered by Sunshine. Designer and inventor Knut Karlsen recently unveiled slick set of SunCat C-cells that are wrapped in flexible photovoltaic panels and will slowly recharge when left to bask in the sun. The SunCat batteries circumvent chargers completely by integrating solar cells within the batteries themselves. To make these prototypes he attached 1.8V flexible photovoltaic cells onto 1.5V NiMH rechargeable batteries and connected them with a conductive silver pen and a few flat wires. The effect is similar to a trickle charger, which slowly charges a battery and can be left attached indefinitely without overcharging.
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