There are lots of batteries which uses a solar panel to it, but these panels are not useful because of the small surface, and The HeLi-on USB charger looks like have a good solution for this with its rollable solar panel. He-Li has a large solar panel, battery inside, its rollable design make the HeLi easy to carry, and He_li on will let you charge your device in 2-3 hours.
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With HeLi users can charge their external device in two ways; unroll the solar panel and charge directly from sunlight or use the internal battery.
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The He-Li on can be charged either with the solar panel or with any USB charger. The HeLi-on charger is compatible with any device charging through USB, including Smartphones, flashlights, cameras, portable game consoles, walkie-talkies.