how do i connect 8 small 1.5v rechargeable cells in both parallel and series so it can power a USB?

i recently got a load of solar garden lights from pound land (mainly for the rechargeable cells) how would i still charge them from the solar panels but have the output as USB instead of the little LED's and obviously i would need to increase the voltage so I was wondering if anyone new how i would connect 8x 1.5v batteries to get essential 2x 6v batteries by connecting four in series and then connecting them to another set of four in series to make the 2x 6v ones, and then how i would be able to have an input to charge form the solar panels and an output to USB, a diagram would be amazing, i am a total novice at electronics, i know the basics but past that i really need some precise guidance, thank you

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DoctorDv5 years ago
Lets just say the batteries are 500ma. If you put four in series then you would have 6v 500ma. Do that twice so you have two sets of 1.5v batteries. Wire both of the sets together in parralel so you have 6v 1000ma. Now run the panels through a 5v regulator (cost $2 at radioshack) and you should be done. If I were you I wouldn't mess around with charging devices using this method. I would buy a simple USB charging circuit that cost $3. You could just buy a Neewer emergency USB charger and have a solar panel charge the two AA's that run it. I hope this helps!

On The 3dge (author)  DoctorDv5 years ago
would this be a gd buy for the 5v regulator with usb female
I think the Neewer chargers are your best bet, but I say go for it for any other method, because you can only learn by experimenting! I hope your project works!

Now that you have the info you need to create the battery pack you want lets address the issue of trying to charge them with the solar cells that came with them. You can try to charge them from the solar cells but you will need to give them a couple of days of charge time. The battery and solar cell where meant to run a small LED. Which wouldn't run the battery all the way down. So all the solar cell had to do it top off the battery. So a full day of sun was plenty to top off the battery.
A better idea would to put 5 of the cells in series to get 7.5V, then drop it down to 5V with a 5V regulator. You can charge the 5 cell pack by putting 5 of the solar cells in series and putting them across the battery.