1.  

The PV panel is made of 100 identical PV cells in series. Each cell has the reverse saturation current 0.7 nA at 25C, the short-circuit current of 5 A, and the open-circuit voltage of 0.60 V. The parallel and series resistances are not considered when the panel feeds a 48V 200Ah battery with an internal resistance of 0.09 2. First draw the V-I curve of this panel, then sketch the battery V-I linear characteristic. Do they cross each other? If yes, calculate the time needed to charge the battery from 30% to 90%, assuming the charging process is linear over this range.