MrWizard wrote:
your assuming, in storage, fully charged no use, only parasitic drains, and full charge everyday, replacing the tiny self discharge drain
Not assuming anything. It's documented by the trimetric and the data log of the controller. When the solar comes on in the morning it spends a period of time in MPPT, a few minutes in absorb and switches to float for the rest of the day.
Is there a DOD that defines a cycle? In my mind a period of charge followed by a period of discharge is a cycle. I'm not trying to defend the article, just trying to find out if there is merit to it.
Here's another quote from
Wind & Sun Deep Cycle Battery FAQ.
"This does NOT mean you cannot go to 80% once in a while. It's just that when designing a system when you have some idea of the loads, you should figure on an average DOD of around 50% for the best storage vs cost factor. Also, there is an upper limit -
a battery that is continually cycled 5% or less will usually not last as long as one cycled down 10%. This happens because at very shallow cycles, the Lead Dioxide tends to build up in clumps on the positive plates rather in an even film."
