Another Lifepower4 balance issue, suggestions?

[watchdoc]

I have a single Lifepower4 battery hooked up to a Growatt 3000 LVM-ES with communication. Few months ago it started acting up overnight from self consumption where the SOC would drop below 5% and trigger a grid charge even though the inverter is set to OSO.

Email SS and their response was to update firmware and perform manual Top balance for several weeks which I did.

Still having the same issue where there battery drops to ZERO seemingly out of blue with anywhere from 5%-8% charge left which triggers a grid charge. Ive emailed SS a couple more times about this issue and gotten no response in 2 weeks.

Battery has been in service approx 10 months and gets cycled approx every other day while charging my Leaf.

I suppose its worth noting this occurs with the inverter off. I plan to leave it on overnight for a few days and see if anything is different. The Growatt's MPPT will charge the battery with the inverter off but exibits some wonky behavior when charging this way.

Any suggestions?

 

[sunshine_eggo]

What was the manual process, and what was the outcome? Were all 16 cells at or above 3.45V with 0A input after the process?

This appears to be classic imbalance coupled with heavy utilization. <10% charge means uncertainty even on a reasonably balanced battery. You may also have an actual weak cell.

 

[watchdoc]

I hooked up the laptop a couple dozen times during the manual balancing. SS sent a set of simple instructions but the main jist of it was 58v charging and let it top balance for hours at a time after its full. I watched various cells here and there and I would think one was weak and then it would balance and wouldn't appear weak anymore. Max cell voltage differential would vary from .00 after top balancing to .022 but I didn't watch it all the time. I'm not sure if I was getting to the full 3.45v so I'll do a couple manual charges and see. I've read several "balancing guides" here, from EG4, and from SS and none of them are exactly the same. Is there a "official" guide???

My SOH is 90.8% with 215 cycles.

 

[watchdoc]

What was the manual process, and what was the outcome? Were all 16 cells at or above 3.45V with 0A input after the process?

This appears to be classic imbalance coupled with heavy utilization. <10% charge means uncertainty even on a reasonably balanced battery. You may also have an actual weak cell.

So I went back to USER mode and set the charge voltage to 58.4v and did a full charge. Several cells reached 3.5v (and overvolted) while others lagged behind. I left balancing for hours and when I came back all the cells had settled around 3.36v. I guess that's as good as it's gonna get??

 

[Brucey]

Email SS and their response was to update firmware and perform manual Top balance for several weeks which I did.

Is this a common thing? I thought an advantage of buying a commercial off the shelf product was that they were ready to go?

 

[Brucey]

Or is this related to the use of passive balancing in the battery design?

 

[gotbeans]

Is this a common thing? I thought an advantage of buying a commercial off the shelf product was that they were ready to go?

right? I'm DIY my batteries currently. It seems just as easy as managing these off the shelf units. and easier since I know all the ins and outs of them.
I'm that "other" thread OP references in his title "Another"

lifepower4 stops charging at 94%

I see plenty of balancing posts etc but no info on this type of thing. I do have it connected to the inverter so it has communication. I assume it isn't going to 100% because it is unbalanced? One cell must be maxed out? Do they become unbalanced this easy? I've only had it on 3 months. It was...

diysolarforum.com

my new batteries will be about 12 times more storage total than the lifepower4. I might just get rid of the lifepower4

 

[watchdoc]

Is this a common thing? I thought an advantage of buying a commercial off the shelf product was that they were ready to go?

appears to be a bms software issue related to the top balancing routine of the batteries. my battery has never stopped working but the cells have gotten out of balance and I'm trying to manually get them back in balance to reclaim some capacity.

 

[gotbeans]

appears to be a bms software issue related to the top balancing routine of the batteries. my battery has never stopped working but the cells have gotten out of balance and I'm trying to manually get them back in balance to reclaim some capacity.

Did you update the firmware? I guess I have to do that now.. gotta carry some computer over to it and set it up lmao. Maybe I'll get some $30 laptop off craigslist to do it
I have mine doing 55 volts floating as said in the other thread

 

[watchdoc]

Did you update the firmware? I guess I have to do that now.. gotta carry some computer over to it and set it up lmao. Maybe I'll get some $30 laptop off craigslist to do it
I have mine doing 55 volts floating as said in the other thread

Yes, I updated to 3.32 about a month ago. I think 3.34 is out now. My issues haven't been fully resolved yet.

 

[gotbeans]

Yes, I updated to 3.32 about a month ago. I think 3.34 is out now. My issues haven't been fully resolved yet.

I'll be leaving mine in the USER config forever since my other ones have no comms with inverter
you may have to do the same =[

 

[watchdoc]

I'll be leaving mine in the USER config forever since my other ones have no comms with inverter
you may have to do the same =[

USE mode is just fine but you don't want to charge at 58.4v forever. You'll need to change it back to 56.2v after balancing IMO. I'm sure some others will chime in on the subject.

 

[gotbeans]

USE mode is just fine but you don't want to charge at 58.4v forever. You'll need to change it back to 56.2v after balancing IMO. I'm sure some others will chime in on the subject.

it's 55.2 volts in the other thread. You're the only one I've seen go as high as 58.4 which is 3.65 per cell

Recommended Charge Profile for DIY LiFePO4 Batteries *Sticky Post*

12V 4S LiFePO4 Battery w/ BMS: Absorption: 14.5V Float: 13.6V Inverter Cut-off: 10.7V-12V (depending on size of load and voltage drop etc) 24V 8S LiFePO4 Battery w/ BMS Absorption: 29V Float: 27.2V Inverter Cut-off: 21.4V-24V 48V 16S LiFePO4 Battery w/ BMS Absorption: 58V Float: 54.4V...

diysolarforum.com

I go with "long life"
float 54.4V
absorb 56.4V