2V 160mA for each

SUNYIMA 10pcs Mini Monocrystalline Solar Cells Solar System Kit 50mm X 50mm/1.96" X 1.96" 2V 160MA for DIY Charge Solar Panels

• Operating voltage: 4.8-6V

Adafruit Universal USB / DC / Solar Lithium Ion/Polymer charger - bq24074

The Adafruit Universal USB / DC / Solar Lithium Ion/Polymer Charger  can use USB, DC or  Solar power, with a wide 5-10V input voltage range! The charger chip is super smart, and will reduce the current draw if the input voltage starts to dip under 4.5V, making it a perfect near-MPPT solar charger that you can use with a wide range of panels.

I broke this board because the batteries I bought have opposite polarity to the Adafruit one.

So I gave up using this board...

I connected 3 pieces of the solar panel as serial connection.

The open voltage was around 6.5V