Board Heat from LiPo

I recently bought a 650mAh, 3.7v lipo from amazon with a JST-PH connector for my notecarrier-af. Upon inserting it, I felt it the surrounding board heat up almost immediately, prompting me to pull it out. The battery has a 50C discharge rating, which I assumed was not necessarily a problem if the device didn’t pull that much power. So far the only other way I’ve powered the AF is with the micro-USB connector, utilizing a direct connection to my PC and to a USB Battery which has a max output 5v 1.5A (The kind you can use to charge your phone). So, did I make a mistake purchasing this particular battery? Thanks in advance!

Hey @dave, thanks for the question and welcome to the community!

Unfortunately, it looks like you have a battery with its polarity reversed, which is common among LiPo batteries used in the RC industry. You can confirm this by looking at the top of the JST plug with the wires facing towards you and the notch or key facing down. In this orientation, the Red wire should be on the right, which is common in LiPos from Adafruit, SparkFun or AliExpress. Many RC batteries, especially those on Amazon, use a reverse polarity arrangement and the red wire will be on the left.

I hope that helps!



Thank you, Brandon. You are indeed correct. Hooray for loose standards! I suppose they make crossover cables as well, which would fix this.

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