LiFePo4 battery users

[tx2sturgis]

But...what is a cycle?

Does every dip below 100% and back up count as one cycle?

A 'cycle' is a fuzzy term, and can be confusing.

Lithium batteries are also rated in 'lifetime amp hours', which you rarely see for lead acid batteries.

A typical 100 ah lead acid battery might have a lifetime amp hour rating of 30,000. Maybe 50,000.

Meaning you can draw (then recharge) 30 (or 50) amp hours, 1000 times. (in theory, ideal conditions)

A typical 100 ah lithium battery will have a lifetime amp hour rating of around 300,000.

Meaning you can draw the same, for 10,000 times. (again, in theory).

At the end of those lifetime amp hours, the lead acid battery will be near the end of its usable life, where the lithium battery might have lots of usable life left. 

The way you are using your lithium batteries sounds fine to me, and the reason they recharge quickly on your system is because that's exactly one of their primary advantages: quick recharge time. 

In other words, if it aint broke, dont fix it!