If you find yourself lost in the woods or adrift in the ocean, a GPS-enabled Personal Locator Beacon (PLB) is certainly a handy thing to have as it will pinpoint your location for rescuers. The one [Steve Jernigan] has is relatively affordable considering it might save your life one day, but it turns out that replacement batteries for the unit are extremely expensive and hard to come by because the manufacturer would rather you send the unit back to them for refurbishment. So naturally, he took it apart and figured out how to do it himself.

His DIY battery pack consists of a small custom PCB and pair of off-the-shelf 6 volt lithium manganese dioxide cells in a 3D printed enclosure that slots into the rear of the McMurdo PLB. In assembly video below, [Steve] shows how the pack goes together and demonstrates the use of a two-part potting compound in an effort to keep the elements at bay.

Before anyone says it — putting a homemade battery pack into a device which one day might be the only thing standing between you and death is probably not a great idea. [Steve] mentions in the description of this project that this is meant for backup purposes, and that you should really spring for a legitimate battery if there’s a chance you might actually need to be rescued at some point.

If you’re interested in battery pack hacking that doesn’t potentially risk life and limb, fixing the one that came with your cordless drill might be a better project to start with. Continue reading “Rescuing A Rescue Device With A DIY Battery Pack” →