Drew Fustini's Simple Coin-Cell Battery Tester Is a Curving Single Board of OSH Park Flex PCB
Clever cut-outs let the flexible PCB bend a full 180 degrees, coming into contact with both battery terminals to light an LED.
OSH Park's Drew Fustini has shared an open source design for a simple battery tester, made out of a single board of OSH Park's flexible PCB substrate and designed to fold over the positive and negative terminals of a coin-cell battery.
"This flexible PCB is designed to a test battery like a CR2032 coin cell," Fustini writes of the project. "The board has cut-outs to allow it to fold over the positive and negative terminals and, if the battery has a enough voltage, turn on a LED."
A single 0603 surface-mount LED with matching resistor sites at the middle of the board's design, in an island created by the clever cut-out sections. Two cog logos sit at either side of the board, exposing the copper and providing contact points: Simply place the negative terminal of the battery on one and bend the flexible PCB 180 degrees to bring the other end in contact with the other terminal.
Introduced two years ago, OSH Park's flexible PCBs are based on a polyimide substrate and can be produced single or double-sided. It's proven popular for a variety of projects, ranging from an ultra-tiny implementation of the Annoy-A-Tron to a flexible handheld console.
Fustini has shared the board's design files on GitHub under the permissive Apache 2.0 license, as well as offering them for sale on OSH Park for $6.40.
