Boost Converter
Here is the design:
http://opencircuitinstitute.org/content/solar-battery-charger
Here is a recording (with commentary) of the entire design (I don't really go in to theory here, however):
Solar Battery Charger - Component Selection
Solar Battery Charger - Schematic Layout
Solar Battery Charger - Circuit Layout
I created a calculator page to automatically generate component values for the circuit based off of desired characteristics.
http://opencircuitinstitute.org/content/boost-converter-component-calculator
Just wanted to let you gents know that this exists now.