It is using the PowerFilm 6V 100ma flexible solar panel. These flexible solar modules can wrap around a 2" pole!
4 AA Includes Ni-MH (Nickel Metal Hydride) batteries, either 1700mAh AA. If completely discharged, the AA batteries would require about 17 hours of sun to fully charge.
Use this little charger for your own project or a homemade backpacking charger. Wires could be cut and lengthened as needed for your application.
from:
http://www.solarhome.org/flexiblesolarbatterychargerfor4aaswithbatteries6v100mapaneland4aani-mhbatteriesincludesblockingdiode.aspx
更新1:
「加多一個電路」的意思是什麼? (因為沒怎麼學過, 所以不清楚..)
更新2:
增加電壓以減少充電時間, 即是串聯多一至兩個solar panel? 這以嗎?
更新3:
"做一個電路"即是什麼? 要如何做一個電路,而不用兩塊solar panel也能加快充電速度?