How can I check the voltage output of my solar panel

[gdawgtuk]

I have 12 small solar powered outdoor lights that I bought from Walmart but they absolutely sucked. I want to use them for other projects but I don't know their output. It had a 1.2v Rechargable battery with it, but it also appeared to have a resister on the board. Can anyone tell me the easiest way to see what it outputs?

Also, do they follow the same rules as batteries? If its output is 4v can I use 3 with a resister to achieve lets say, 8v?

 

[ShockSlayer]

Multimeter is your best option.

Dunno if you can wire them in series like that or not.

 

[Spoleyo]

I made a small stupid solar panel as a fun project. They were weak so yes, i wired a few in a series to up the voltage.