Consumer marketplaces, including Amazon, eBay, and AliExpress, are absolutely inundated with sellers peddling fraudulent products. That’s especially true for batteries, because most consumers lack the knowledge and tools to test them. If you buy lithium batteries (or products that contain them), there is a very good chance you’re getting scammed and the batteries will have, at the very least, much lower capacities than specified. The result can be anything from an annoyance to a legitimate danger. To prevent that, Open Green Energy designed this DIY 18650 battery tester anyone can build.
The purpose of this device is to give makers the ability to easily test 18650 lithium batteries to verify their capacities. If a seller advertises their batteries as something like 9900mAh, you can use the tester to check that. It will give you a pretty accurate estimate of the actual capacity, such as 3500mAh. In this example scenario, you would…
