Real World Exp with DOD/cycle life of lifepo4 over 10yrs old? 15? 20?

[Athens Jim]

Hey Guys..
as stated in the subject, who has lifepo4 systems older than projected life expectancy??

aside of coarse from every batt mfg that states their DOD/CYCLE expectancy as an estimate.. im mostly curious if the batteries cycle expectancy of 5000 is at 50% DOD, will it last longer than projected if DOD is 10% - 20%, say 8000 cycles? if maintained at that same 10-20% ofcoarse..

1) will it take an unexpected dive at some point or gradually lose capacity?
2) inability to reach full charge?
3) abnormally rapid discharge?

and...
based on your personal experience, is it better to keep the system at 95% or let it go to 100% SOC?...

 

[hwy17]

We don't really know because hardly anyone has got there. It should be a loss of capacity, not a loss of ability to get to full charge voltage. Loss of capacity will result in an abnormally rapid discharge.

The batteries are better off sitting at 30-70%, but they need to be taken to 100% once in a while in order to balance them. 95 is better than 100 too, but can't be balanced at 95 either.

 

[Athens Jim]

We don't really know because hardly anyone has got there. It should be a loss of capacity, not a loss of ability to get to full charge voltage. Loss of capacity will result in an abnormally rapid discharge.

The batteries are better off sitting at 30-70%, but they need to be taken to 100% once in a while in order to balance them. 95 is better than 100 too, but can't be balanced at 95 either.

thanks for quick reply hwy17..

ive been reading up and cant seem to come to a conclusion so i figured ide ask here if anyone has hands on

i did however find an abundance of info thats pretty much 50/50..

suggestions have been to keep DOD low to prolong cycle life, but no real world stats on if it actually does, and for how much longer..
others say leave as is and buy new batts every 10-12 yrs..

but i havent found anyone that has typed " i have" or "mine are".. but then again, i havent found anyone actually asking what im asking either..

so here i am


as far as 95% vs 100%.. i asked that cause ive seen some BMS and inverter charge parameters have the option to charge based on elapsed time, i.e., charge to 100% for 30-720 minutes, then drop to 50%-100% maintain/float..