charge controller settings for 10% to 90%

RandyP

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After a full charge to 14.2-14.6v, where do BattleBorn's settle in an hour?

Would this be with absolutely no load on the batteries ? Main Battery disconnect open, VBM battery voltage fuse pulled ?
 
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MisterSandals

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Would this be with absolutely no load on the batteries ? Main Battery disconnect open, VBM battery voltage fuse pulled ?
Yes thats settling. With a load its discharge.
Mostly curious where the BB's settle because the are supposed to be charged so high. This is what you should base YOUR float value upon to prevent micro-cycling.
 

RandyP

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Yes thats settling. With a load its discharge.
Mostly curious where the BB's settle because the are supposed to be charged so high. This is what you should base YOUR float value upon to prevent micro-cycling.
OK, I'll have to wait a few days to do that. There will be a small load, the BMS for the B/B LiFePO4 battery.
 

Gould

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Based on these popular charts:

90% charge is about 13.5v. So knock down your 14.x charging to here.
I would set your float to .05v below where your battery settles in an hour (this prevents micro-cycling).

I would put low voltage warning around 12.8v (20%) and disconnect at 12.6 (10%).

See how this works with YOUR batteries and anxiety levels (this is conservative so should be stress free). If you need more out of your batteries while traveling, charge higher, like to 13.8v (my 95% for MY battery).

FWIW, when my RV sits in my driveway, I turn off charging (solar cutoff breaker) and let batteries sit around 13.2v. A couple days before a trip I will turn on charging to 13.8v so fully charged.
Facing the same questions as I powered up my SCC for the first time last night. Not sure what I’m missing with the SOC table referenced 90% is 13.40 not 13.50. 13.50 is 99%?
 

MisterSandals

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Facing the same questions as I powered up my SCC for the first time last night. Not sure what I’m missing with the SOC table referenced 90% is 13.40 not 13.50. 13.50 is 99%?
Yea, looking closer, following the 90% hash up it looks between the wording of 13.45 and 13.40.

The point being that most of the charge is MUCH lower than people believe they need to achieve (14V to even 14.4V). There's not a lot of extra storage up there. I am a conservative charger and there are more folks aligning this way all the time. I charge to 13.8V and it quickly settles to 13.4V which i consider 100% full.

I've tried charging at quite a few different lower levels and didn't think it charged sufficiently.

All this being said, my cell settle point is 3.35V. Every single one of my 40+ cells settle here. Some folks have cells that settle to 3.5V so i dunno what to say for them. Similarly, i think its important to set the float below the settle point otherwise it will continually micro-cycle. My float is around 3.32V and that works really well for me; you should base YOUR float point on your cells' settle point.
 

Gould

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That clarifies things for me thanks. Makes perfect sense to me and for my setup loosing a little off the top won’t effect anything.

Regarding the float setting, is this the point that the charge cycle kicks off again, jumping to bulk and then to absorbsion?
 

MisterSandals

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Regarding the float setting, is this the point that the charge cycle kicks off again, jumping to bulk and then to absorbsion?
Normally the float value is where it will maintain the charge. There is some point below the float value that will kick it into bulk and this varies between brands. I think this is configurable on some.
 
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