I have many AA NiMH rechargable batteries that I wanted to use to recharge various mobile devices. My goal was to fully charge multiple devices if possible. After searching eBay for electronic parts, I came up with the idea of using a 10 AA battery holder wired to a DC12V car socket. I could then use any USB car charger to recharge my devices using the AA batteries.
Step 1: Parts Required
Acquire the following parts:
- DC12V Car Charger Cigarette Lighter Female Socket Outlet with Wire Leads
- 10 AA Battery Clip Holder Case with Wire Leads
- USB Car Charger with 1 or 2 ports and total current draw <= 3A
- Digital Multi Meter (DMM)
- The 10 AA Battery Holder connects the AA batteries in series
- The wire leads on the DC12V Car Charger Socket have a higher gauge compared to the 10 AA Battery Holder.
- I purchased my parts from eBay
Step 2: Assembly Steps
- Desolder and remove the red & black wire leads from the 10 AA Battery Holder
- Solder the DC12V Car Charger Socket red & black wire leads to the respective terminals on the 10 AA Battery Holder
- Use the DMM to check that the DC12V Car Charger Socket is wired properly
Step 3: Usage
To charge a USB device:
- Insert 10 AA batteries. Note: 2000mAh NiMH AA batteries will give the equivalent of 24Wh.
- Insert USB Car Charger into socket. For testing, use a USB Car Charger with LED light. The LED light should turn on if the Socket is soldered properly.
- Plug in USB device to charge.