I have taken a rechargeable cell for the RTC of Rock PI 4B. Does Rock PI 4B will automatically recharge it or I need to build another rechargeable circuit for it?
Does Rock PI 4B RTC Circuit takes care of recharging the RTC cell?
Do we really need RTC battery rechargeable? Check the rk808 datasheet, the RTC Supply Current is 5uA. You can calculate how long the battery works.
Ok, I am using 235 mAh Button Cell (Maxell LR44 Alkaline Button Coin Cell Battery),
and then
Number of hours = 0.235/0.000005 = 47000 Hours = 5.36 years
Are these calculation correct? 
If yes, Works for me 
Thanks
I suspect a rechargeable option would be preferrable as these devices mind end up in installations that might not see the light of day for more than 5 years.
Guess i’ll skip the battery for those installs