I've seen a few members discussing running fans from rechargeable USB batteries. Most fans are 12v and most USB rechargeable batteries are 5v. I was wondering if two USB cables could be spliced so that the ground from battery 1 is soldered to the positive from battery 2, and then the positive from battery 1 is connected to the red lead going to the fans, and the ground from battery 2 is connected to the black lead going to the fans?
If so, this should provide 10v for the fans. However, I'm not sure if this would affect the overall recharge life of the batteries or damage them in any way. I am just trying to find a uniform rechargeable power source for my helmet fans. Has anyone tried this or have any comments or suggestions as to its viability?
Thanks for any and all replies.