Sometimes I need a camera in some places where there is no easy power supply, so I have to run with a battery. I usually use a UPS, like the one we use for ower computers, but this machine converts from a 12v battery to 220v output, and then, the Yi Home Camera transformer convert from 220v to 5v.
So I thought using a power bank (those which we use to recharge our mobile in a emergency) to avoid even the transformer. I bought the bigger I found, Xiaomi Power Bank 2C 20.000mAh.
The power supply of the Yi Camera is 5v 2.0A. In the Yi Home Camera 2 is noted 4.0W(MAX).
If the camera consumes 4 watts for 24h it involve 96Wh
The battery is rated at 20.000 mAh and 5v, that is 100Wh.
With these data, and assuming that the camera is always at max consumption, (4W) it should last: 100/96 = 25h, a bit more than a day. That assuming:
- The battery could be fully discharged. False, Li-polymer battery can be discharged 80% as much
- The camera consumes 4W all the time. False, I have tested the camera with a consumption-meter for a full week and it consumes 2.4W in average.
So now the calculations are: (80%100Wh)/(2.5w24h) = 80/60 = 32h
Now my test. I full charged the power bank, set it to low current output mode (according to power bank user guide this funcion is for small devices, fitness bands, watches, bluetooth headsets and other small gadgets), and place the camera in my cottage. I set it up recording continiously (not only when motion is detected) at 1080p @25fps (max quality) and disabled all other stuff like gesture recognition o baby crying recognition. The camera was with no WiFi connection (perhaps it was searching for WiFi all the time and that is a battery consuming operation). It started recording August 19, 2018 at 20:56h, and the last slice of recording was at August 21, 2018 at 06:37h.
So, my Yi Home Camera 2 connected to a Xiaomi Power Bank 2C as power supply continuosly recording last 33 hours and 41 minutes.
Wow!!! Only a 4,3% of deviation between theory and reality.
- With WiFi connection linked, not always searching.
- With motion detection only recording. I suposse it will increase autonomy because of not writing continiously to the sd card. On the other hand motion detector is a CPU consuming operation…
Anyway if you got here, perhaps you have to have a look to Blink cameras and this Blink cameras with AA batteries but be aware of region lock before purchasing one.