LT3652 based MPPT solar charger for a single LiFePo4 cell
The LT3652 is a 2A multi chemistry MPPT charger controller from Linear Technology. You can charge other cells by simply changing the values for R1 - R4 (R1 and R2 actually are one resistor with 223k for LiFePo4) according to the datasheet. Set the trim potentiometer to 2.8V on pin VIN_REG at full sun on the solar panel.