Solar Batteries

Recharging Batteries with Solar Cells
Rechargeable batteries are a boon to eco-enthusiasts who use portable electronics, however all too often they require additional peripherals in order to keep them charged. These devices generally take the form of a black box loaded with non-biodegradable plastics and heavy metals - not very earth-friendly.
Karlsen’s 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.
Karlsen plans to continue to tweak the batteries, adding capacitors to charge the batteries more efficiently and electronics to check when the batteries are full. We’re excited to see the results of his testing - finally, a justification for all those see-through gadgets with clear cases.

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