HOW TO – USB Li-ion battery charger
I love neelandan’s electronics they’re gritty – “This is a charger for lithium ion batteries which takes its power from the USB port of a computer. It uses the MCP73861 or MCP73863 Li-ion battery charger chip manufactured by Microchip.” – Link. Related: HOW TO – Vehicular 5V power – Link. Minty Boost kit – Link.