I bought a $5 usb charger that I am using to power my Raspberry Pi. The charger works decently but I am noticing that every once in while the raspberry pi will reboot. I have read that some chargers that supply 5v often drop under 5volts. Does this mean I need a battery that supplies a little over 5volts? I also read that any voltage over 5 will fry the pi? Can someone explain how to properly select a battery to buy for the Raspberry Pi B?

  • Is the issue with the amount of current the charger provides?
    – sirshakir
    Commented Feb 4, 2019 at 22:24
  • yes, the pi needs anywhere up to 2.5A depending on which model pi, and what you're doing with it - I've easily gotten away with 2.1A on a headless pi3 with some tweaks, even with a SDR dongle attached Commented Feb 4, 2019 at 22:32
  • You also need to think about the quality of the usb cable - the official power supply uses 18AWG cable.
    – CoderMike
    Commented Feb 4, 2019 at 22:51

1 Answer 1


The best answer would come from the system designer, in this case the Raspberry Pi foundation. You don't say which Raspberry Pi you have. The 3 is notorious for being finicky about voltage drops, the 3b less so in my experience.

The Foundation says "The Raspberry Pi 3 is powered by a +5.1V micro USB supply. Exactly how much current (mA) the Raspberry Pi requires is dependent on what you connect to it. We have found that purchasing a 2.5A power supply from a reputable retailer will provide you with ample power to run your Raspberry Pi."

Note they said 5.1V, not 5V.


  • The 3 is notorious for being finicky about voltage drops, the 3b less so which models exactly are you talking about? There is no '3'. There's a 3B, 3B+ and 3A+
    – Dirk
    Commented Feb 5, 2019 at 7:12

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