Battery charging with salt water
Bumped into this recently. It might be useful for a go pack or some other emergency situation. http://www.greenivative.com makes a device which is capable of charging AA, AAA, C, D batteries using salt water over magnesium anodes. Also has a USB adapter to charge any device with that interface. Price is about $55. The downside is that it can only be used about 15+ times before the magnesium is consumed and apparently there is no replacement available. Not very practical for day to day use, but if you have money burning a hole in your pocket and see this as a viable alternative during a true emergency, it might be something to add to the bag.
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