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Battery talk (A place to discuss any and all battery technologies where the discussion may not fit into other topic areas) => Lithium => Topic started by: SoilGuy on November 27, 2018, 04:56:32 PM

Poll
Question: Does anyone have experience charging LFP batteries with a wind/solar hybrid system
Option 1: yes votes: 0
Option 2: no votes: 2
Title: Hybrid LiFePO4 charging system
Post by: SoilGuy on November 27, 2018, 04:56:32 PM
I am looking into upgrading my power generating system for remote research sites in NE Indiana. I currently am using solar to wet cell batteries. We have been happy with this setup until the past 3-4 years. Winter in NE indiana is killing us with its cloudy periods lasting well into weeks on end.  I would like to upgrade to a LFP chemistry (100 Amp Battle Born) and add a Primus 40 Air 40 to the sites. All components at each site are 12V. I am concerned about the charging profile required for the battery since the turbine doesn't do a whole lot of controlling. Any thoughts??
Title: Re: Hybrid LiFePO4 charging system
Post by: ClassicCrazy on November 27, 2018, 07:01:29 PM
What are your loads ? And how high would you be planning to put up the wind generator ?
For all the expense and maintenance a wind generator needs , have you analyzed any way to make your loads more efficient and increasing battery storage capacity and PV ?
Is your battery going to be in a warm place ? Lithiums usually can't be charged below freezing.

Larry
Title: Re: Hybrid LiFePO4 charging system
Post by: RossW on November 28, 2018, 04:22:12 AM
Quote from: ClassicCrazy on November 27, 2018, 07:01:29 PM
increasing battery storage capacity and PV ?

This. 1000x this.

For 13 years I was offgrid with AGM and PV. Even with what seemed to be "plenty" of capacity (1000AH @ 48V) of battery, I was averaging 1000 hours generator run per year.

A few years ago, I changed out all the AGM for LFP. With 900AH of LFP, (more "usable capacity" than the AGMs), and adding more PV than I can use, that has dropped to about 6hrs/year of generator run time, and most of that is a half-hour run every couple of months!

Over-paneling means even on crappy days, we generally get enough to hold our head above water, and with PV being as cheap as it is now, why wouldn't you?!
Title: Re: Hybrid LiFePO4 charging system
Post by: ClassicCrazy on November 28, 2018, 11:11:20 AM
Yes Ross  - I just almost doubled my PV input and it already has noticeable effects on getting the batteries full on overcast days and cutting down generator run time - especially up here in the frozen north short days of winter.

Larry 
Title: Re: Hybrid LiFePO4 charging system
Post by: SoilGuy on November 29, 2018, 08:45:27 AM
Thanks everyone for the advice. I wasn't too excited about putting up 50 30' towers. The batteries will be in heated space. I guess I'm going to reassess the wiring/charge controllers and PV capacity at my sites and probably try a couple of the Battle Borns to get one right before a heavy investment.