LIFePo4 lifecycle with ~60% of discharge per cyle

[rkts]

Hi,
Sorry if this been covered elsewhere but I could not find this info...

Just took stats from CA for last year with MP3 and MP4 for my 48V 10AH LiFePo4 battery - 160 cycles, 900AH.
Doing simple math it gives around 5.6AH per charging cycle that is a bit less than 60% of battery capacity.
I cycle all year round. My comfort riding temp varies from up to +30*C at summer to -12*C in winter. Actually temp drops time to time below -25+*C here in winter but after few rides below -15*C I decided that -12*C is that minimum temp that I'm comfortable with. When garage temp is below +5*C I charge battery at home with timer delay (to let it warm up to ambient temp).
My usual route is home to work and back in total of 26km (16miles). Due terrain it takes me around 1.5-2Ah to go to work and around 3-4AH to return. I'm pedaling all the time. As for speed it's around 32kph (20mph) half of journey and much lowers speeds later.

Definitely I have too small battery to do two days per charge so I'm charging it every day.
Any thoughts how it will influence a total lifecycle of battery? To avoid discussions regards LiFePo4 lifecycle let's just assume that LiFePo4 battery lifecycle with 100% capacity is that promo 2000 cycles.
I'm not sure how they rate this - on 100% discharge, 90% discharge X discharge or it doesn't matter?

I'm thinking is it worth to change charging plan and charge at work as this is a bit more complicated than to do at home. In that case I could change charging pattern to something like this - work->home(2ah), home->work(2ah) -> work->home(4ah) and then charge. This is a bit risky as due voltage drop I will most likely consume more AH on last ride to work before charge but might work with some special battery saving techniques. And It's even more risky in winter...

[Flipseth]

Check out this info, I have found it helpful.

http://batteryuniversity.com/learn/article/how_to_prolong_lithium_based_batteries

Thanks Phill

[Bikemad]

Definitely I have too small battery to do two days per charge so I'm charging it every day.
Any thoughts how it will influence a total lifecycle of battery? To avoid discussions regards LiFePo4 lifecycle let's just assume that LiFePo4 battery lifecycle with 100% capacity is that promo 2000 cycles.
I'm not sure how they rate this - on 100% discharge, 90% discharge X discharge or it doesn't matter?

Even if your battery was big enough to last for two days it is better for the battery to only be partially discharged to 50% and recharged every day than it is for it to be completely discharged over two consecutive days and then recharged.

If you're only using 6Ah out of the actual 10Ah it would probably be better for the battery's longevity to only charge to about 80-90% instead of charging 100% each time. This would allow you to use 6Ah (60%) every day and still have plenty in reserve (30-40%) making it less likely that you would discharge the battery too far.

You would need to study the voltage reading on the Cycle Analyst to try and ascertain what the typical battery voltage is after 1.5Ah has been used from the fully charged pack. This would give you a rough indication of where you battery voltage should be after it is charged to 85% capacity.

If you measure the used capacity each day (eg. 6Ah) you should be able to set a timer for the correct amount of time to put just the right amount of charge back into the battery (2 hours charging at 3 Amp charge rate = 6Ah capacity replaced) to bring it back to the original 85% capacity again.

If it works correctly, the battery voltage should be pretty close to the typical battery voltage observed after 1.5Ah had been used from the fully charged pack.
After a bit of trial and error, you should be able to eventually work out how much longer (or perhaps shorter) the charge time needs to be set for in relation to the amount of capacity used.

Unfortunately, there is no way of confirming whether all the fiddling around with partial charging and not fully discharging will actually extend your battery's life, but theoretically it should. 

Alan