That internal Li battery is about the size of motorcycle battery, I could build one those units at a 1/4 or 1/3 of cost they charge, of course I need somewhere to buy time...
Pure Capitalism at its best. Take a bunch of components, do some R&D, put them together, test them, market them, then sell baby sell.
Pretty good write up about them with videos and comparison charts here:
► WARNING! READ BEFORE YOU BUY | Kodiak Solar Generator Vs...
I'm done with lead acid batteries for anything but vehicles. Also stopped buying AA, AAA, C, D, 9volt throw away's years ago. Going full retard on rechargeable batteries, but not rechargeable gear. Some of my friends are going 100% rechargeable devices, but I like being able to use standard sized batteries for ease of finding another power source if my rechargeables take a crap in an apocalyptic type setting. Only things I have that are rechargeable are a radio, cell phones, and a small power bank for camping that charges my cell phones and radio

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