18650 Battery charger reverse polarity protection #Battery #Safety

Naive Diode

Vince blogs about the safe way to charge the standard 18650 battery.

Having many 18650 battery cells to charge, I bought a few dirt cheap TP4056 modules (0.22 EUR per piece) and discovered that they are “not designed for” reversed polarity cells. In other words, reversed battery = instant magic smoke.

As I know for sure I will insert more batteries in the wrong orientation again sooner or later, I wondered what the best reverse polarity protection would be. This thread addresses this very topic, but at the time of this writing, it ends with:

Q: “Has anyone actually tested this solution in real life?”

See the videos below (one, two, three, and four) and the blog post for details.

 


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1 Comment

  1. Jamie Flournoy

    Thanks for this! I bought a 10-pack of TP4056-based boards and am finding more and more probably-not-optional features of a good charger that aren’t included on the boards I got. :/ Putting a positive spin on it, it’s a good learning exercise, trying to decide what I absolutely need for given applications, and trying to figure out what a simple and reliable way to implement each of them is. This is a great help, especially with the “this seems like a good idea but isn’t and here’s why” options. 🙂

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