DIY Dummy Battery Emulator Adapter AA by Inversion

Last crawled date: 3 years, 1 month ago

This is a great way to power your battery powered device from an AC power source or from a DC / USB power source as I have in this project. The idea was to retro fit some dummy batteries into my portable speaker, so that I could use a 15000 mAh dual USB port power bank to power the speaker (and the mobile / cell phone) for longer duration's whilst out and about.
Just by chance, a friend was moving out and he had lost the AC power adapter for his iPhone / iPod docking station and he said that I could have it. Great! However, I quickly found out that it would only last for a few hours before the batteries needed changing again. I thought about it and decided to make some solder free dummy batteries to emulate the batteries. I wasn't sure at first if the 5V delivered over USB was enough so I did a quick test and it worked fine. 4 x 1.5 Volt batteries would be 6 V and not 5 V, so I measured the state of some old batteries that I used in the device before it failed and they fell to about 1.1 Volt each, giving you a combined 4.4 V. Seems its might run along the bottom line at times, but it sounds great, even at high volumes :)
Now I have wired it up to the USB battery and all the four LEDs on the USB battery are still active after 6 hours of music! Seems that the average, decent battery is about 1000 mAh, so this is the equivalent of 15, instead of 4 ;)
Works a treat. Hope this helps someone as it did for me.
3D Printed on a Ultimaker 3D Printer