Howto use USB to Recharge Lithium Battery (Li-Ion)

Short answer from article: Use a standard USB->battery charger IC. There are a bunch of them on the market.

Two extra tidbits:

1) Most (all?) of these ICs are surface mount only. Come to the 21st century you through hole barbarians.

2) The article implies that drawing more than 500mA will shut down a USB port. This would be nice, but consider that the people who designed your laptop/desktop/whatever can save $1/unit by leaving out the USB overcurrent protection. They probably did.

Interesting article, great the application/example Single Chip Battery CHARGER from USB

For an embedded system with USB that requires recharging of Lithium batteries there are many considerations to be made before you can safely, accurately and quickly recharge the batteries.