Hi,
I need to create device that uses 10 mA and has long battery life- at least one year.
The device should be small and is for indoor use.
I calculated that if I use 2 3.7v 6000mah batteries I will have 2 months live.
I was planing to add solar cell and I tested them but all of them except one were not working at all on ambient light.
Do you have any ideas how I can power this device with battery and solar cells for more then year.
The consumation is 5-10 mA - I am planning to implement sleep mode to reduce the power consummation but I really need to reach at least one year battery life.I have space for max 6-8 AA batteries.The device will work with 2-3V.
Maybe I need solar cell for ambient light but all I have tested were not working on ambient light.
Any suggestions?
Thanks
10mA => 0.010 * 24 * 365 = a battery of 8700 mAh
Your 2 * 6000mAh should last a year. Or is this calculation wrong ?
EDIT: It is 87000mAh !
What's the device?
With careful programming the Arduino chips can use power in the microamp range. What else is in your device using power?
the calculation would be 1024365 = 87,600 mAh as we are talking about ma. That's 87.6 Ah, which is not a small battery.
What is the device? And can you not make it more efficient?
If it's to be used indoors, is there no AC power available??
Could you run a small cable out side for a small solar cell? It would not have to be that big.
Thanks for the replays.
I will have nrf24 wireless module + atmega8l + LCD without backlight.
I plan to use the nrf24 for 10 second every 1-2 minte to reduce the power consummation.
The amorphos solar cell that I tested is giving me 1/3 of its voltage on sun light.
It seems to me that the amorphos solar cells may do the job but if somebody has additional ideas it will be great.
Why can't the solar cell go outside?
If that is impossible, what about using 3 or 4 solar cells in series to increase the voltage?