Powering Arduino With a Battery




Introduction: Powering Arduino With a Battery

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Make your Arduino projects portable by using a battery for power. From the Uno and Mega documentation pages:

"The board can operate on an external supply of 6 to 20 volts. If supplied with less than 7V, however, the 5V pin may supply less than five volts and the board may be unstable. If using more than 12V, the voltage regulator may overheat and damage the board. The recommended range is 7 to 12 volts."

I've found that using 9V works well. You can simply connect the + end of your battery to Arduino Vin and the - end to Arduino ground (fig 1). You should see the green light on the Arduino turn on to indicate that it is powered.

It's also a good idea to attach a toggle switch in series with this battery so that you can turn your Arduino off and on. As shown in the images above, solder a toggle switch to the red lead from the 9V battery connector. Connect the black lead from the battery connector to one of the Arduino's ground pins, and connect the lead from the toggle switch to Arduino's Vin pin. Snap a battery to the connector. Now your Arduino will turn on when the switch is closed and turn off when it is open (figs 5 and 6).

Parts List:

(1x) Arduino Uno Amazon

(1x) 9V Battery Amazon

(1x) 9V Battery snap connector Amazon

(1x) toggle switch Amazon (this one is a little different that that pictured, but it will work the same)

Alternatively, you can find these 9V snap connectors with the same n-tye barrel plug as the Arduino and plug into the barrel socket on the Arduino directly:

(1x) 9V battery snap connector to barrel plug Amazon

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65 Discussions

Hello sir.I have a question.When Arduino is off draw current?Please answer.Thank you

1 reply

If you use a switch like on here, then the circuit will become physically disconnected when turned off, so no it won't.

Worked for me with a 4 AA battery pack

So you program your arduino using a computer and then disconnect and run that program off of a battery? correct? I am assuming you can only run one program then ? To switch to another program you would have to start over with a computer?

1 reply

Yes that has to be necessary, as new code has to be loaded using the loader

i want to use a Lipo battery for my RC car project,what should i do and dont?

1 reply

mine works only if connected.why is it so?

i am using 12v 8000mah battery for robowars

can i connect it directly to arduino?

How shall i make it work

If this was a rocker with an led where would you wire the led in

Looks like that is turning into a real product: https://bitbucket.org/talk2/whisper-node-avr/overview

The chip is rated at max 5.5V, I dont know if the Vin passes through regulator. are you about this?

1 reply

ok so googling says

If you use the VIN pin, you bypass the diode, but you still have the dropout voltage of the regulator,

But regulator will eat your battery

Do you know for how long the Arduino will operate if we never turn off the supply?

1 reply

I found out the hard way that this is not a good way to power an arduino! Read this article:


I bought a whole bunch of rechargeable 9V batteries thinking it would be a good system. They generally can't power the my nano for more than a day. The article above describes why.

can i use external 5v 6A power supply to power the arduino?

i bought this power supply for my ws2812b led strip which works on 5v.

will it burn the arduino, will it be safe?