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NeonHorizon / lipopi

Guide to setting up LiPo batteries on the Raspberry Pi
GNU General Public License v3.0
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How long does the battery last? #4

Closed oskarpearson closed 8 years ago

oskarpearson commented 8 years ago

Hi

Thanks for this - looks useful!

Would you be able to update this with details of how long the battery lasts with different capacity batteries, based on your experience with it?

Oskar

NeonHorizon commented 8 years ago

Hi Oskar, You can calculate this using the watt hours.

For example if you have a 2000mAh battery and we presume that its 3.7v on average this gives you 3.7v x 2000mAh which is 7400mWh

If we now look at the power consumption of a Raspberry Pi we can work out how many Watts it uses. I use Alex's RasPi.TV site as a reference: http://raspi.tv/2016/raspberry-pi-zero-1-3-power-usage-with-camera

So if we pick a PiZero shooting video thats 240mA @ 5v, which is 5v x 240mA = 1200mW

So we now know our battery has 7400mWh of capacity and the Pi uses 1200mW. So 7400mWh / 1200mW = 6.16 hours.

Therefore a PiZero recording video will last 6 hours on a 2000mAh battery :)