Lifepower V2’s

Charging and discharging by voltage for a long period of time shouldn't be an issue. When you installed the new V2 batteries, were they within 0.5V of the other batteries?

@eric  yes they were around .2 volts difference so well below .5 volts. 

So if the batteries are in lithium mode should or we shouldn’t run in voltage mode? SS said they would only cycle properly in lead acid mode. When I’m done cycling them in lead acid mode 7 or more times and switch back to lithium does EG4 recommend using SOC? Thanks 

Yes, charging by voltage in lead acid mode would be the best approach. I’ve attached a document that explains how to properly top balance the batteries.

Switching back to SOC control should be fine as long as everything is communicating properly.

Is the inverter reading all the batteries?

As long as you're charging them to 100% and discharging to around 20% a few times per month, you shouldn’t experience these issues again.

EG4-LL-Recalibration-Guide.pdf

I’ve been in lead acid mode trying to deep cycle them so it doesn’t show them. I’ll get the BMS test done tonight and look at them. Phillip and I will probably talk this week. He is curious about what is going on. 

my whole problem with SOC is when I deep cycled the original 6 batteries 7-8 times the showed 0% at 47 volts. I thought they should’ve read 20% at 47 volts. That’s why I left them on volts. I was afraid to use SOC but I should have and told the generator to start at 0 or 1% I guess in lithium mode

47V is definitely not 0%, but it is considered below 20%. Voltage is a more accurate reading because the inverter measures it directly from the battery. SOC, however, is estimated by the battery’s BMS and can sometimes be less precise.

The reason people choose SOC, is because it does communicate with the inverter and if something is wrong with the battery, the inverter will let you know. Instead of having to be checking on the battery every time through the BMS Tools software.

@eric , so is SS right when they say Do not run lithium mode by volts?? Will that damage the batteries or inverter?  I know a few guys that need to know the answer. Thanks

It will not cause any damage. When I mentioned running by voltage, I was referring to using Lead Acid mode on the inverter. However, I haven’t heard of anyone experiencing issues running the inverter in Lithium mode while using voltage-based charging and discharging.

@eric thanks

@eric I’m still get a difference in charge and discharge on the new V2’s compared to the 9 older ones. I’m going to put a picture up and show you how I have them wired and see if you think I should do something different.

How do you have the batteries connected? 
Are you using external bus bars?

@eric 

2 EG4 battery racks connected to 18k with 2, 3/0 cables for positive and 2, 3/0 negative. The 2 racks are connected by a 4/0 positive and a 4/0 negative cable. Here is how it looks

@pawnee If I remember your OP correctly, the three new V2's are just filling out your second rack?

The original setup was charging all batteries correctly and it wasn't until you added the new V2's to the second rack that batteries started charging and discharging strangely?  And only the new batteries?

@joel-brodeur Yes last 3 of the 12. It's pretty strange. When PV or discharge is low, they all pull the same amps. When PV or discharge is high the newest batteries pull around half the amps. It usually goes like this.

Charging from 47 volts to 54 volts or so most batteries are pulling 10 amps and the new ones 5 amps. Around 54 volts the older batteries BMS start slowing down charge amps to say 1.5-2 amps and the new batteries start pulling 10-11 amps until they hit 56.4 where I have the 18K charge limit set. I'm still in lead acid mode cycling them so I'm hoping after a few more cycles they even out. If the age difference in the batteries was a couple years apart. I would expect some difference. The oldest batteries have around 250 cycles on them so I can't image that being the problem. I still can't get BMS test to work so I'm in the dark. I'll try to hook up to them again today or tomorrow and see what's going on.

Do you see anything wrong with the way I have the racks wired?? I can't think of a better way to do it, so I don't think it's a current sharing problem.

@pawnee I don't see anything wrong with the wiring.  It was working fine 9 batteries?

Just curious, have you tried an amp clamp to see if it actually charging/discharging differently and not just reading incorrectly on the monitor?

Offhand it almost seems as if the BMS is limiting higher charges and discharges.

That is a strange one.