Probably easier and cheaper to build these sensors from fresh to optimize data gathering and energy use, maybe by having a large solar PV charger attached.
It is a good idea to add a solar charger to it, I recently found a solar panel for $1 from a Chineese store and it works great. By recycling and resuing old smartphones the cost of such a device can be significantly reduced. Also it is easy to connect IOT sensors to smartphones easily and connect the same with internet.
I would appreciate if you could support my proposal.
Thanks & regards