I have a project in mind that will require solar power and standby battery.
This will largely be a charge from the sun device with occasional wake up and 100 ma power consumption.
My initial thought is LA would be ideal but i would like to keep both mass and volume small.
My understanding is that if not cycled, lipos should be periodically discharged.
For long time storage (float with occasional use ?) a charge level of 40 % is generally recommended.
So should i over size the battery and charge to 40% only or stick to LA.
Given the cost of lipo i would like best longevity, these batteries would have seasonal use but i would like them to last many years.
I thought it was 60% for optimal maintenance of capacity with LiPo. I don't think LiPo has a memory effect like NiCd's did, so you don't need to discharge them. They don't like being float charged at 100%, or stored like that for long periods of time (and they really hate being overcharged, even a little - I had a cheap charger for cell battery when the charging port failed, and I had to charge my phone battery outside the phone. Within a couple months of doing that for a week (and then installing the new connector and charging normally again), all the batteries it had touched had puffed up and were thrown out. Turns out the charger didn't actually have proper overcharge protection... )
4 Ah should be plenty for summer seasonal use , not much used overnight,
There are many thing i would like to monitor.
Reporting could be by many means but basically a hive sits on it's own in a radius of other hives dependant of food supply.
There will be a 0.5m squared solar cell or thereabouts per hive and a battery.
Performance yet to be determined as web results are profuse and unreliable.
I would like to work out the energy budget first to see what is possible to achieve.
DrAzzy:
I thought it was 60% for optimal maintenance of capacity with LiPo. I don't think LiPo has a memory effect like
For modelling use the figure seems to be 40 %
But these batteries are normally used as deep discharge not for float applications, lithium ion batteries used in power tools etc i think have more tolerance , they are more bulky though.
My application is more of a float charge type but i cannot find much on the suitability of these batteries for this application.