Charging current of cubecell development board

#1

Hi, I am working with cube cell development board to collect data from remote place where power is not available. I have to use solar panel with reasonable battery capacity. I am thinking of using 2600 mAh lithium ion battery with 10 w solar panel. I need to know the charging current of the onboard battery charger to find out the duration for charging the battery. I couldn’t find this information in the technical specification. This place is away from my present location so I cant go frequently if the module not working properly.
I need to collect the data for every minute and sensor consumes approximately 100 mA for every reading. The entire system should run for 15 days without sun shine (considering worst monsoon season). The place where I am going to install the sensor is getting average sun shine except monsoon season.

I am also thinking of LoRa kit from heltech instead of cube cell series which is newly released and having some issues.

suggest me the suitable battery capacity, rating of solar panel and others if any

Thanks in advance

#2

Hi Saravanan,

welcome!

You should do the math first. Calculate the worst case. OK. Your worst case is 15 days without sunlight, so charging current is not in the formula (for now).
15 days, 24 hours, 60 minutes sum up to (d*h*m) 21600 readings. You assume 100mA per reading, so you need a 21600*100mAminute battery. Thats makes it to a 36000mAh battery just for the worst case.
Not included self-discharge in this time-frame. I hope I did the math right :wink:
Tell us more about this sensor, why is it soo power hungry?
(You might already have seen that the above calculation is rubbish. I suppose that your sensor will not draw 100mA for a complete minute, but you didn’t mention how much power, for how much time the sensor “eats” :slight_smile: )

BR
Marc

#3

thanks tuxscreen for the reply
Sorry I just forgot to mentioned the duration. it operates at 3.3 v and draws approximately 100 mA for 100 ms.

#4

You can do the math now, right? Or do you still need help?

BR
Marc

#5

In the case of sufficient charging power, the charging current of the CubeCell to the battery is 70mA.