Raymond711

Hello all. Late to the party on this conversation but having a Sunsynk 5KW and some lithium batteries means that we often discover things as we go along.
@bernardf posted his time of use settings. 
My unit is basically set to 100% from 8am to 6pm. So the batteries only charge during the day when there is sufficient sun. Then discharge in stages from 6pm to the following 8am all the way down to 30% SOC. I have ticked the load priority checkbox so when load is high during the day, it stops charging the batteries for a period of time to attend to the load and blend with grid if necessary. So on a good sunny day my 7kw of batteries are usually charged by 1pm. Thereafter the PV attends to the load for the rest of the day.
Not really concerned whether @Bernardf's settings are good or bad, i am more interested about the way the batteries work. So in his setup, theoretically, the battery could be charged and partially discharged multiple times in the day. If the load at any point in the day demands more than what PV can supply and if the the battery has the required SOC for that time of day, the system could engage the use of the battery to power the load in tandem with PV and maybe even grid. When load demand drops, PV may get back to charging the battery.
MY QUESTION IS: When the battery charges up to maybe 80% then allowed to discharge to perhaps 65% and then charge up again, is this not using up a charging cycle of the battery???
If this is true, then does it mean that multiple charge cycles are used up each day, and therefore reducing the lifespan of the battery???
With lithium batteries quoting in excess of 6000 cycles (based on DOD), the above scenario, if true, could mean that the batteries state of health (SOH) could deteriorate well before the claimed 10 years that most lithium vendors make. 
Any comments on the above???!!! Not sure if this has been discussed in another thread before.