Victron Multiplus 3000 and EG4 Lifepower Battery Compatibility Issues?

[SoCalKevin]

But, he's got the 12 volt version, not the 48 volt version.

So he's pulling something like 450+ amps surge from packs that are rated at 200 peak amps each?

With some luck that might work, but if one pack has slightly lower internal resistance, that one is going to trip for over current, then the load all falls to the second pack and it obviously trips over current.


OP, your old batteries probably don't have a protection circuit (BMS) built in, so yes they do fine.
In my opinion you didn't do enough research and bought batteries that need to run at 120% or more of their rated current to work. Or you need a third.
But, Richard from signature is right, try full charging them a couple times. You might get that extra bit you need.

Thanks for the informative reply @400bird

But if that surge is only .5 second or so, is it really that big of an issue in the grand scheme of the battery life? Once that quick surge fires up the compressor, the draw goes way down.

Yes, i will fully admit i am newer to this and my detailed research may have lacked for sure. I saw 200a max discharge and assumed (we know that never goes well) that 2 of them would have me at 400a and id be fine. Ooops. I most definitely dont have room for a third,

As for fully charging them...

Theyve definitely both been fully charged via the charger from Signature Solar before i installed them.

But for cycling. Do you mean drain them down as low as possible and charge them again?

Thanks

 

[rmaddy]

But, he's got the 12 volt version, not the 48 volt version.

Whoops. Sorry I missed that. That's a big difference.

So the 5000W inverter surge would be 5500W at the batteries. At 13.5V that is 407A or about 204A per battery.

If the batteries were nearly drained and at 12V then it would be about 230A per battery. So the higher the battery voltage the lower the surge amps.

 

[SoCalKevin]

Thanks for all the advice and info guys!

It’s appreciated!

Back to work tomorrow so not sure when I’ll get to try to troubleshoot this again, but I’ll post updates here when i do, in case others have the same issues.

 

[400bird]

So the 5000W inverter surge would be 5500W at the batteries. At 13.5V that is 407A or about 204A per battery.

If the batteries were nearly drained and at 12V then it would be about 230A per battery. So the higher the battery voltage the lower the surge amps.

Yeah, I did my math at 12 volts.

I hadn't included what Richard from Signature mentioned, if he had any base load before the AC kicked on. Any base or already running loads are going to make it much worse.

Thanks for the informative reply @400bird

But if that surge is only .5 second or so, is it really that big of an issue in the grand scheme of the battery life? Once that quick surge fires up the compressor, the draw goes way down.

You're probably right there. No big impact, but the BMS is going to do what it's programmed to do. If the programmer said trip at 200 amps and you hit 201, it's going to trip.

Yes, i will fully admit i am newer to this and my detailed research may have lacked for sure. I saw 200a max discharge and assumed (we know that never goes well) that 2 of them would have me at 400a and id be fine. Ooops. I most definitely dont have room for a third,

Sorry, I shouldn't have called you out. But there's been multiple threads recently where everyone throws signature solar under the bus and from my perspective it's not always been their product at fault.

As for fully charging them...

Theyve definitely both been fully charged via the charger from Signature Solar before i installed them.

But for cycling. Do you mean drain them down as low as possible and charge them again?

Thanks

We'd need to leave that to signature solar to get definitive answers, but the BMS's I've worked with only needed to fully charge once and the SOC resets. But he said try it a couple times. I'd guess taking them down to 70% would do it.

 

[SoCalKevin]

Sorry, I shouldn't have called you out. But there's been multiple threads recently where everyone throws signature solar under the bus and from my perspective it's not always been their product at fault.

Oh, i have zero issues with that whatsoever and you're 100% correct.

@RichardfromSignatureSolar replied to my post on a SUNDAY on a non work day...

Signature has been great through all of this.

For me, its one big learning process.

 

[SoCalKevin]

Ok, so here is an update...

NOTE: Both @RichardfromSignatureSolar and everyone i have talked to at @Signature Solar has been amazingly helpful trying to troubleshoot this and have even offered a full refund if i couldnt get it to work. Top notch customer service!!! This is NOT a rant against them!

NOTE #2: There was zero issues with these batteries and the Victron Multiplus drawing even much higher loads with the water heater and coffee maker running. This is an isolated issue with the air conditioner.

I went through every single connection on my system and made sure it was tight and secure, and then did more testing, even had an electrical engineering buddy supervise to make sure i was doing everything right...

The highest draw we saw was 186a (at 12v) when the compressor kicked on. We did 2 tests and the average was about 184a.

We tested these both as 2 separate batteries, and with them wired in parallel. All same results.

Every single spec listed for these batteries says this should not be an issue and the BMS should handle it fine, even as single units.

Before proceeding, i contacted Victron 2x and researched the issue on the Victron forum. Everything pointed to battery BMS issue.

I disassembled one of the batteries, which was MUCH nicer quality and durability than i expected, and was pleasantly surprised to see the BMS was very simple to bypass.

Bypassed the BMS on one of the batteries, reconnected it, started Air Conditioner, and it started up and ran flawlessly for an hour. Spike at start up was around 170a and no issues.

Bypassed the second BMS, tested that one separately and also performed perfectly.

Connected batteries in parallel and put everything back together with both BMS bypassed. Everything A-Ok

The BMS software is password protected so its more of a battery MONITORING software, and NOT a battery MANAGEMENT software.

Going through the BMS software on my laptop shows some weird stuff.

Other than the random mispelled words, on both batteries, it is listing the capacity as 100ah and a SOC of 386% on one of the screens, not 400ah.

But on another screen it lists it properly. This is not a changeable setting, weird. I will attach pics below.

Soooo.. At the end of the day and a lot of testing and troubleshooting, i am still happy and satisfied with these batteries, but i will be replacing the BMS on both of them ASAP with a better, more programmable BMS unit with more stable and user friendly software.

Yeah, i am aware i just voided my warranty, etc, but it is what it is... I only have so much free time i have to make what i got work

For now, there are enough settings in the Victron stuff, i can protect it from over/under charge, etc...

Hopefully i dont end up having to post in the UP IN SMOKE section of this forum. HAHAHAHAHA.

Here are some photos:

 

[John Frum]

Those under voltage and over voltage trip values are too low and too high respectively.

I would like to see the datasheet from the cell manufacturer but for all the big blue aluminum case prismatics that I have seen the range is 2.5-3.65 volts.
@RichardfromSignatureSolar

 

[SoCalKevin]

Those under voltage and over voltage trip values are too low and too high respectively.

I would like to see the datasheet from the cell manufacturer but for all the big blue aluminum case prismatics that I have seen the range is 2.5-3.65 volts.
@RichardfromSignatureSolar

I’m also a bit confused the specs say the absorption and float are both 14.1 ??‍

 

[John Frum]

I’m also a bit confused the specs say the absorption and float are both 14.1 ??‍

I would love to hear the reasoning behind that.
Its not what I would do.

 

[400bird]

Great testing, glad you've got a plan for the replacement. I'd agree with others, those BMS settings are not what I would have chosen...

Have you picked up out your replacement BMS brand?

The highest draw we saw was 186a (at 12v) when the compressor kicked on. We did 2 tests and the average was about 184a.

Were you using an amp meter with in-rush function?

The BMS software is password protected so its more of a battery MONITORING software, and NOT a battery MANAGEMENT software.

I'm not sure that's the distinction.
This BMS still does cell balancing and has the ability to disconnect the pack when it "thinks" it needs to protect the cells.

 

[SoCalKevin]

Great testing, glad you've got a plan for the replacement. I'd agree with others, those BMS settings are not what I would have chosen...

Have you picked up out your replacement BMS brand?

Havent chosen a replacement BMS yet. I have to do a lot more research first. Preferably one that communicates with Victron products

If not mentioned, this setup is in an off grid RV. I have a trip coming up that i just had to delay a week to fix these issues.

Once i get back from the trip i will take it all apart and redo it with a different BMS, etc....

Any suggestions?

Were you using an amp meter with in-rush function?

Yes sir

I'm not sure that's the distinction.
This BMS still does cell balancing and has the ability to disconnect the pack when it "thinks" it needs to protect the cells.

Gotcha. makes sense. Thank you

 

[houseofancients]

if you indeed want a different bms, with similar capabilities, the only one i can think of would be a seplos.

i would however, first discuss with @RichardfromSignatureSolar about getting a bms from a ll version.
in other cases these seem to be able to handle the inrush better

 

[Solar Guy Richard]

Thanks for the update! I'll talk to my tech bench if it's possible to manually swap out the battery BMS between the 2. Not sure if they ever did it, but I can't imagine why it wouldn't work.

Edit: Only worry I have is the LCD screen and if the formfactor would match.

 

[SoCalKevin]

Thank you very much for all your help @RichardfromSignatureSolar

I am currently doing as much research as possible regarding which BMS intergrates best with the Victron VE Bus system and will go from there.

Thanks

 

[SoCalKevin]

i would however, first discuss with @RichardfromSignatureSolar about getting a bms from a ll version.
in other cases these seem to be able to handle the inrush better

Thanks, i am not aware for a II version. I thought these were the latest/newest

 

[Solar Guy Richard]

Thanks for the update! I'll talk to my tech bench if it's possible to manually swap out the battery BMS between the 2. Not sure if they ever did it, but I can't imagine why it wouldn't work.

Edit: Only worry I have is the LCD screen and if the formfactor would match.

I just checked - although we haven't ever actually done this test in house, we don't see any reason it wouldn't work. I'll see if I can find a few batteries to frankenstein together.

 

[SoCalKevin]

SUCCESS AND PROBLEM SOLVED!!!

So I wasn’t sure if this would work or not, but I figured I’d give it a go.

Ordered the 120a BMS from Overkill Solar and a 200a breaker from Blue Sea.

Took one of the batteries apart this AM to swap out the BMS.

Much to my surprise the plug with the lead wires and such was identical between the EG4 BMS and the Overkill Solar BMS. I tripled checked that they were all the same labels and functions and they were. Sweet.

Removed the EG4 BMS, replaced it with the Overkill unit, added the 200a breaker for extra measure, plugged it in and boom, bluetooth worked and confirmed everything was done correctly and the cells were balancing.

Big test, I started up my air conditioner and even though it spiked as usual, it started up and ran the inverter fine. Super happy about this!

It was wayyyyy easier to swap the BMS than I expected and I’ll snap some pics when I do the other battery next week!

So if anyone else is having issues with their EG4s, this is an option.

The overkill bluetooth BMS software is night and day better in my opinion and the phone app integration is great and very user friendly

I’ll post photos when the other BMS and breaker show up and i convert the other battery

The breaker doubles as an on off switch should I ever need to shut the battery off

Thanks for all the advice

 

[Horsefly]

SUCCESS AND PROBLEM SOLVED!!!

So I wasn’t sure if this would work or not, but I figured I’d give it a go.

Ordered the 120a BMS from Overkill Solar and a 200a breaker from Blue Sea.

Took one of the batteries apart this AM to swap out the BMS.

Much to my surprise the plug with the lead wires and such was identical between the EG4 BMS and the Overkill Solar BMS. I tripled checked that they were all the same labels and functions and they were. Sweet.

Removed the EG4 BMS, replaced it with the Overkill unit, added the 200a breaker for extra measure, plugged it in and boom, bluetooth worked and confirmed everything was done correctly and the cells were balancing.

Big test, I started up my air conditioner and even though it spiked as usual, it started up and ran the inverter fine. Super happy about this!

It was wayyyyy easier to swap the BMS than I expected and I’ll snap some pics when I do the other battery next week!

So if anyone else is having issues with their EG4s, this is an option.

The overkill bluetooth BMS software is night and day better in my opinion and the phone app is great.
I’ll post photos when the other BMS and breaker show up and i convert the other battery

Thanks for all the advice

I know you said earlier you were using integration with Victron as a primary criteria. If you are using the JBD BMS and the Bluetooth, aren't you giving up on Victron integration?

 

[SoCalKevin]

I know you said earlier you were using integration with Victron as a primary criteria. If you are using the JBD BMS and the Bluetooth, aren't you giving up on Victron integration?

Yeah, that was my initial plan.

But the more research I did, the more and more people I found that were happy with the Overkill / JBD bluetooth units so i figured that was my safest bet.

 

[Horsefly]

Yeah, that was my initial plan.

But the more research I did, the more and more people I found that were happy with the Overkill / JBD bluetooth units so i figured that was my safest bet.

Yeah, I get where you are coming from. I built a couple of 4S batteries with JBD BMS's for a friend that was upgrading from lead acid and almost all Victron. A few people here tried to convince me to go with a REC BMS ($$$$) but I just put a Victron Smart Shunt on the battery bank and it has all been working well, with the shunt reporting the SoC to the Cerbo GX just fine.