I have a 48 volt 200 amp hour battery pack it seems to be degrading

[Buick39]

Then you have the option of setting the bulk and float values in the MPPT. Find the highest bulk voltage that doesn't trigger over-voltage protection. Set float to 0.1V below bulk. hold it there for 24 hours. You should see the high cell voltage come down and at least 1 of the others increase.

I will try that tommorow thanks

 

[Buick39]

I will try that tommorow thanks

Well I had discharged it down to 70% via EQ really had all the voltages within a 10th of a volt but not exceptionally very high average voltage per cell was 3.25 area I will post some pictures of the cells after the charge downside I just lost another part of my amp hours it was at 180.5 prior to charging

 

[Buick39]

Well I had discharged it down to 70% via EQ really had all the voltages within a 10th of a volt but not exceptionally very high average voltage per cell was 3.25 area I will post some pictures of the cells after the charge downside I just lost another part of my amp hours it was at 180.5 prior to charging

I can't remember what video it was don't think it was on this equalizer might have been a balancer that it would take and look for the highest voltage and try to match all the other batteries to it I'm thinking that I'm going to have to get this voltage up to gain some of my amp hours back. What voltages is everybody else seeing on their cells?

 

[Buick39]

I can't remember what video it was don't think it was on this equalizer might have been a balancer that it would take and look for the highest voltage and try to match all the other batteries to it I'm thinking that I'm going to have to get this voltage up to gain some of my amp hours back. What voltages is everybody else seeing on their cells?

Little more information I did pull the equalizer out and took a few more pictures this might be a pace BMS although I can't quite see all the numbers you get exact match I'm currently running a discharge on it with a space heater and going to let it charge back up again thanks for all the help

 

[400bird]

From roughly 3.2-3.4 volts which is something like 20-80% SOC, the voltage will be incredibly flat, but the actual SOC for each cell can be wildly differing. You need to get the cells up above 3.5 volts, then look at and try to balance the cells. In the middle, flat part of the voltage curve, they will always be equal.

Remember the SOC and capacity are guesses, or as the programmers want you to call them, algorithms. Until you get the underlying assumptions met, both SOC and capacity will be inaccurate. Garbage in, garbage out.

I can't remember what video it was don't think it was on this equalizer might have been a balancer that it would take and look for the highest voltage and try to match all the other batteries to it I'm thinking that I'm going to have to get this voltage up to gain some of my amp hours back.

Please remove and stop trying with the lead acid equalizer. It's like try to trying to fix a roof leak with latex paint. It just isn't close to the right product for the job.
Yes, your equalizer does what you say, try to match the four 12 volt batteries it is connected to, but you have 16 3.2 volt cells.

What voltages is everybody else seeing on their cells?

Lifepo4 voltage range is 2.0-3.65
Outside of about 3.0-3.5 volts there is very little useful capacity in the cells.

 

[Buick39]

From roughly 3.2-3.4 volts which is something like 20-80% SOC, the voltage will be incredibly flat, but the actual SOC for each cell can be wildly differing. You need to get the cells up above 3.5 volts, then look at and try to balance the cells. In the middle, flat part of the voltage curve, they will always be equal.

Remember the SOC and capacity are guesses, or as the programmers want you to call them, algorithms. Until you get the underlying assumptions met, both SOC and capacity will be inaccurate. Garbage in, garbage out.


Please remove and stop trying with the lead acid equalizer. It's like try to trying to fix a roof leak with latex paint. It just isn't close to the right product for the job.
Yes, your equalizer does what you say, try to match the four 12 volt batteries it is connected to, but you have 16 3.2 volt cells.


Lifepo4 voltage range is 2.0-3.65
Outside of about 3.0-3.5 volts there is very little useful capacity in the cells.

Yeah I guess the plan right now is the discharge it down a ways which I'm doing right now and recharge it check the voltages on all the batteries probably is going to a assortment of voltages and as I said the eqs taken out even though it was recommended for lithium batteries as well in the description. I guess my best step will probably buy a variable power supply 5 or 10 amp.

 

[SparkyJJO]

Remember the equalizer is to balance BATTERIES to each other. Each battery is made up of individual CELLS. That is a battery level balancer, not a cell level balancer. The BMS should have some type of cell balancing built in, but you HAVE to be at the upper range of charge for it to work because, as mentioned, the voltage of each cell is pretty flat across the majority of the state of charge. You cannot tell cell state of charge (balance) at 70%.

 

[Buick39]

Remember the equalizer is to balance BATTERIES to each other. Each battery is made up of individual CELLS. That is a battery level balancer, not a cell level balancer. The BMS should have some type of cell balancing built in, but you HAVE to be at the upper range of charge for it to work because, as mentioned, the voltage of each cell is pretty flat across the majority of the state of charge. You cannot tell cell state of charge (balance) at 70%.

I agree and currently running a space heater on the system and do another discharge then recharge and take a look cell voltages and see if they get up over 3.32 area. I keep thinking I watched a video on a balancer and it would take the high voltage batterys and bring the lower ones up to them but I could be wrong? If that is the case and by discharging and charging brings some of the voltages up then might be better in the long run to put one of the balancers in as recommended earlier in the conversation https://www.amazon.com/Equalizer-Ba...cing/dp/B096NMJW12/ref=asc_df_B096NMJW12?th=1

 

[400bird]

That is how it works, brings down high batteries.
The description also shows it is for 4 (or 8) 12-volt batteries.
For lithium batteries those would be the drop in 12 volt replacements that look like a standard 12 volt car battery.

 

[400bird]

as recommended earlier in the conversation https://www.amazon.com/Equalizer-Ba...cing/dp/B096NMJW12/ref=asc_df_B096NMJW12?th=1

Please don't take my link as a recommendation for that product. That one might be junk.
I was just trying to provide a reference so you'd know what you're looking for.

Search the forum here, there will be plenty of recommendations.

 

[Buick39]

Please don't take my link as a recommendation for that product. That one might be junk.
I was just trying to provide a reference so you'd know what you're looking for.

Search the forum here, there will be plenty of recommendations.

Understand

 

[Buick39]

So this last test was to drain it down to about 78% took equalizer off recharged and here's the current battery voltage is now if you notice the FCC screen used to say 199.9 amp hour recently it said 180.5 amp hour it drops seems like every time I charge and discharge in a course of 6 to 8 months. I went ahead and ordered a variable power supply cuz I thought about building a battery Bank down the road and I think this is leaving me no option but to individually charge the batteries up to maybe gain some my amp hours back

 

[SparkyJJO]

Cell 6 and 10 are the highest ones. If it is held at float charge for a few hours the BMS should be bleeding them off while charging the others still.

 

[Buick39]

I

Cell 6 and 10 are the highest ones. If it is held at float charge for a few hours the BMS should be bleeding them off while charging the others still.

left everything on for the night to see if the BMS might raise voltage and balance out some. I took another picture of the bms model number and trying to see if I could find the spec's on it ..... I tried to reset the unit a couple of times but didn't seem to change anything ..
The number I can see on the bms is P16S100A-DL0641-20A doing a little searching on this BMS looks alot like this one dont see any software to access it http://www.pacebms.com/en/index.php/shows/32/11.html

 

[augiedoggy]

Please don't take my link as a recommendation for that product. That one might be junk.
I was just trying to provide a reference so you'd know what you're looking for.

Search the forum here, there will be plenty of recommendations.

I use that one and have had good luck with it. (I did buy mine from aliexpress for $44 though and I bought the 12-16s version) Keep in mind these are only intended to be plugged in temprarily to either top balance or bottom balance when something like this occurs. You can leave the wires all connected and just unplug the connectors after using it to balance. If you leave these connected they can actually throw your cells out of balance but it does depend on the size of the cells and how well they match each other in performance and current draw use.

Most bms units have very small low amp passive balancing that can take a long time with no use on the battery to balance... more and more bms units are starting to come with active balancing now which takes voltage from the higher cells and redistributed it to the lower voltage cells. many of these bms units only turn the active balancing on for a certain voltage range when the cells are at a certain level of charge.

 

[Buick39]

I use that one and have had good luck with it. (I did buy mine from aliexpress for $44 though and I bought the 12-16s version) Keep in mind these are only intended to be plugged in temprarily to either top balance or bottom balance when something like this occurs. You can leave the wires all connected and just unplug the connectors after using it to balance. If you leave these connected they can actually throw your cells out of balance but it does depend on the size of the cells and how well they match each other in performance and current draw use.

Most bms units have very small low amp passive balancing that can take a long time with no use on the battery to balance... more and more bms units are starting to come with active balancing now which takes voltage from the higher cells and redistributed it to the lower voltage cells. many of these bms units only turn the active balancing on for a certain voltage range when the cells are at a certain level of charge.

I really appreciate the information I just a msg back this morning from the guy I purchased it from and he reached out to another guy that responded back and said he put a active balancer on his unit and says it works great now But my guess he has left it wired in all the time.. thanks for sharing about not leaving pluged in all the time had no idea. I think I have found the BMS in my system but dont see any spec other that it is a 100amp http://www.pacebms.com/en/index.php/shows/32/11.html Will have to look to see how hard it would be to remove if I was to consider a BMS change instead may not be worth while. Thanks again for your input

 

[augiedoggy]

I really appreciate the information I just a msg back this morning from the guy I purchased it from and he reached out to another guy that responded back and said he put a active balancer on his unit and says it works great now But my guess he has left it wired in all the time.. thanks for sharing about not leaving pluged in all the time had no idea. I think I have found the BMS in my system but dont see any spec other that it is a 100amp http://www.pacebms.com/en/index.php/shows/32/11.html Will have to look to see how hard it would be to remove if I was to consider a BMS change instead may not be worth while. Thanks again for your input

be sure to watch he followup videos that go into what he found when he left it connected all the time and why.