(http://lookpic.com/O/i2/572/Gatb5SgP.png)
ANNE_CAP
Based on the Analog Devices Quad SAB Mosfet balancing IC for supercaps up to 1,000F 3,000F.
This layout is for 35mm 2.7v 500F supercaps.
I chose the ALD810022SCI which will keep the caps balanced at 2.2v.
Datasheetwww.aldinc.com/pdf/ALD8100xxFamily.pdf (http://www.aldinc.com/pdf/ALD8100xxFamily.pdf)
Particular need for 8.8v to suit a 9.2v 4.7w cell for charging, i opted for an easier build
using ebay ams1117-5/3.3v three pin regulators for output.
On the layout i convert 6.6v to 5v & 4.4v to 3.3v since the 1117's require input to be at least 1v above required output.
And here are the gerbers for OSH Park :)