Jan-24-2022 07:47 AM
Feb-14-2022 07:59 AM
Feb-14-2022 06:06 AM
3 tons wrote:
Had another good off-grid solar day today, with no meter monitoring, or intervention (100% passive)…
Stats:
200 a/hr LFP (actual load-tested at 215 a/hrs), 440w solar
Starting SOC @ 0700, 41% SOC
End of Day SOC @ 1900, 85% SOC
In approximate terms: A harvest recovery of about 44% of SOC (or 88 a/hrs) to arrive at 85% SOC…
3 tons
Feb-14-2022 05:55 AM
jaycocreek wrote:
Interesting and always nice to see individual reports..I have been reluctant to mount solar on my roof,one because of water intrusion and the other,less solar output than aiming at the sun but also there is less fuss mounted..
Yesterday I did the same with one 100 watt portable solar panel and one 100ah LFP..Started at 51% and ended at 83% moving it two times..Plus 30AH roughly...
Feb-13-2022 09:24 AM
Feb-13-2022 08:04 AM
Feb-13-2022 07:02 AM
jaycocreek wrote:3 tons wrote:
Had another good off-grid solar day today, with no meter monitoring, or intervention (100% passive)…
Stats:
200 a/hr LFP (actual load-tested at 215 a/hrs), 440w solar
Starting SOC @ 0700, 41% SOC
End of Day SOC @ 1900, 85% SOC
In approximate terms: A harvest recovery of about 44% of SOC (or 88 a/hrs) to arrive at 85% SOC…
3 tons
Interesting and always nice to see individual reports..I have been reluctant to mount solar on my roof,one because of water intrusion and the other,less solar output than aiming at the sun but also there is less fuss mounted..
Yesterday I did the same with one 100 watt portable solar panel and one 100ah LFP..Started at 51% and ended at 83% moving it two times..Plus 30AH roughly...
Feb-13-2022 06:00 AM
3 tons wrote:
Had another good off-grid solar day today, with no meter monitoring, or intervention (100% passive)…
Stats:
200 a/hr LFP (actual load-tested at 215 a/hrs), 440w solar
Starting SOC @ 0700, 41% SOC
End of Day SOC @ 1900, 85% SOC
In approximate terms: A harvest recovery of about 44% of SOC (or 88 a/hrs) to arrive at 85% SOC…
3 tons
Feb-12-2022 09:23 PM
Feb-11-2022 04:34 PM
otrfun wrote:
You mentioned "equalization" again. Why and how would you "equalize" a lifepo4?
Feb-11-2022 05:05 AM
StirCrazy wrote:I get the impression you may be talking about a passive balancer? I've used both passive and active balancers. Neither have worked quite as you describe.
cell ballancing won't happen untill you are full, so by setting equalization and float the same as charge voltage you will allow more time for top ballancing. Im not talking days but maybe an hour or two extra time for the top balancing process depending on your bank size.
StirCrazy wrote:I agree the whole overcharging thing is somewhat overblown. Until we've each had time to flush this out through personal experience, I guess we'll just to have trust companys like Battleborn. When I spoke to them last year, their only caution was not to float their 100ah lifepo4 at 14.6v for more than week or so. It's one small, but important gotcha. They also alluded to the fact that a single-stage lifepo4 14.6v converter/charger would probably not be their first choice for charging a lifepo4 battery. Without a float or absorption stage you run some risk of overcharging---especially if you're the set-it and forget-it type.
most people just charge them and as soon as they reach 100% they turn off the charger because so many people are scard of letting them sit at 100% becasue of myths propagatd that are intended for storage and maybe the issue is the definition of "storage" to me if you are camping you are never in a storage situation. and when I got home from a trip I would probably give it a day on the charger to make sure it was top ballanced then unplug it if I was going out again next week, and not worry about it being at 100%. or run somthing to bring it down to 90% then plug it in again the night before I am leaving to make sure its full for the trip. to me storage is realy when we are talking in terms of months. so lets say I am working a ton of OT at work for the next two months and I know I am not going camping. run the batteries down to 70 or 80% and unplug. but then before a trip I am charging them the night before to 100% again.
Feb-10-2022 08:31 PM
Feb-10-2022 04:32 PM
otrfun wrote:StirCrazy wrote:What do you define as "normal charge voltage" or "float voltage" for a lifepo4?
ya he also mentiond that people thing LFP is more finiky than it actual is with the capacity usage and charging. I learned about the float, and to set it for your normal charge voltage as most people don't let there LFP equalize long enough to actavate the cell balancing. never thought that would be an issue.
When you say "most people don't let their LFP equalize long enough to activate cell balancing", what you do mean exactly? As 3tons mentioned, lifep4's do not require equalizing. Are you saying there's a specific voltage necessary to activate cell balancing? And/or a specific amount of time is necessary to accomplish cell balancing?
Feb-10-2022 12:49 PM
...You can use a voltage range between 14.2-14.6 volts for the bulk and absorption charge stage, There is no problem using an absorption voltage of 14.6 volts. We use a set absorption time of at least 20 minutes per battery because our BMS uses a passive balancing at the top of the charge cycle. When the battery voltage exceeds 14.2 volts this balancing will occur and ensures that the cells remain at the same state of charge, which helps for pack longevity and performance. This preset time will allow and ensure that this balancing occurs. The controller should sense the voltage preset has been hit during its charge cycle which will allow it to move to a float voltage. If a 90 minute absorption does not fully restore the battery and achieve a full charge then it may indicate the battery is out of balance and needs an extended absorption charge to reach a balanced charge. If you have any questions, call us at...
Feb-10-2022 11:34 AM
StirCrazy wrote:What do you define as "normal charge voltage" or "float voltage" for a lifepo4?
ya he also mentiond that people thing LFP is more finiky than it actual is with the capacity usage and charging. I learned about the float, and to set it for your normal charge voltage as most people don't let there LFP equalize long enough to actavate the cell balancing. never thought that would be an issue.