solar fan bodge up

[Rhylsailer99]

After just a few months my fan has failed . I've now joined all the wires together and it's spinning again. I've secured the exposed wires, but is there any risk of the batteries being overcharged on a sunny day, or does the small solar panel not really pump out enough volts to worry.

 

[Rhylsailer99]

Would it be better to just buy a 12v extractor fan pic inserted
below, and wire it straight to the load output on my solar panel controller.

 

[William_H]

As I understand the electronics board is dead. This would control charge of battery but also control discharge. ie switch off before battery is flattened. It seems you have bypassed control and paralleled solar panel battery and fan.
First question to ask OP is what kind of battery is in the fan. A niMh battery or series of cells each 1.2 volts should be no problem with over charging givn small solar panel. Lithium at 3.7v per cell can burst in to flames if over charged but then again small solar panel. lithium would not like to be completely discharged (at night) while NiMH don't mind if single cell. (not good in multiple cell strings) Perhaps just disconnect battery. ol'will