Building a Massive Portable Power Bank
batteries | electricity | hacks | handy geng
If you search around on Amazon, you can find some pretty big portable power banks. But Handy Geng needs more milliamp hours of power, so he got to building this enormous power pack that has batteries totaling 27,000,000 mAh (or 27,000 amp-hours) of power output. And yes, it’s still portable, kinda.