I have an APC Smart-UPS 3000 XL battery backup. In addition to the internal batteries, it has a connector for adding an external battery pack to it. While it's available on Newegg for WAY cheaper than ...

[GreatScott] has now joined the ranks of Electric Bike users. Or has he? We previously covered how he made his own lithium-ion battery pack to see if doing so would be cheaper than buying a ...