Dear Habtamu,

welcome,

Your curves represent an illuminated i-v characteristics drawn in the first quadrant by reversing the direction of the current. So, it is okay. The current in the first figure can not reach zero because you could not reach the open circuit condition which requires a very large load resistance practically open circuit. In the lower you could approach the open circuit point. Therefore you could use it to determine the open circuit voltage.

However you could extrapolate the I-V curve in the upper figure to get an estimation of the open circuit voltage.

I would like to add that your cells have large series resistance and thereby your fill factor will be relatively low.

You have also slight short circuit of your cell.

Best wishes

thanks alot