Turn Used Phone Batteries From E-Waste Into E-Treasure
This hacker shows how to upcycle an old cell phone battery into a usable power source for your next project.
When you’re ready to make your next awesome electronics project, there are a plethora of great boards from which to choose. One little detail that often gets overlooked, however, is how to provide power? Sure, many boards have a built-in LiPo adapter, and a USB charger can be an excellent option, but what about recycling “gently” used cell phone batteries?
As seen in the video and project write-up by hacker “lonesoulsurfer,” doing so isn’t actually that hard. In fact, lonesoulsurfer, has a cell phone recycling box at his work that he often raids (with permission) for free cells. There is a very good chance that you have an unused and/or broken phone at home, or that you too could get this kind of access with a few nice words.
Once your battery is obtained, getting power to and from the cells is a matter of using a voltage regulator and battery charger. lonesoulsurfer’s model cuts off power to the battery once it hits around 4.2V, and can boost the output voltage to 30V if needed. In his case, he sets the output voltage to 5V in order to — what else? — charge a phone. He’s added an auxiliary Micro USB port to the end of the battery for easy access, along with a USB A port for discharge. A digital voltmeter and button is used to check the battery status.
The only thing that’s a little sketchy is that he’s soldering leads to the battery terminals, noting that the batteries don’t really like being heated up. So it seems there’s a bit of an “at your own risk” factor to this build, but one could argue that the same applies with any electronics project.