1. tootoo

    Why is my Hoverboard Motherboard Making This Sound When Powering After Discharge?

    YouTube video with the sound What is this sound, and why does it happen? After discharging the motherboard (turning it on without a power source), and then powering it with a battery, it makes that high pitched noise (before the buzzer beep). Is it the capacitors charging? It makes the same...
  2. flasergames

    LiPo cell overdischarged (down to 0.7V) [charges just fine]

    Hello, I am currently re-purposing my old powerbank for a robotics project (BMS and LiPo will be integrated into a 3D printed case). The Powerbank (CellularLine FreePower Slim 5000) was unused for 7-8 months and while opening It, I measured the cell voltage, which turned out to be ~0.7 V...
  3. F

    Electric discharge from electric motor controller after unplugging battery.

    Hello! I was being a bit careless after unplugging a 48v electric bike battery and I dropped the power cord leading motor's controller, it hit the rim and shorted the remaining current from the motor's controller. (I assume the steel rim completed the connection between the prongs and shorted...