PLEASE HELP - EG4-LL (V1 with updated Victron Firmware) generating Cell Over Voltage at 100% SOC

[Brightside]

Thank you for replying. I have been reading on “Top Balance” and watching YouTube videos. Can you please point me to an article, one of your posts, or a video describing how to do the EG4-LL (V1) Top Balance? It appears that the Top Balance procedure requires one to open the EG4-LL case and attach some type of circuitry to individual EG4-LL battery cells, which can detect if one of the cell(s) starts to charge more than the others and prevent it.

Just float them while monitoring the BMS tools, or the the battery display. Hold the float so that the bad cell is just above 3.40V(ie 3.45-3.50V). This will allow the cells to top balance(no need to do anything external). The balance current is 100mA so it is going to take weeks to months before everything is normal, but it will eventually get there.

 

[Brightside]

Thanks so much for replying and providing information about your case. I started with Victron default MPPT absorption voltage of 56.8 volt (or 56.8/16=3.55 volt per cell) which is lower than where the EG4-LL BMS protection should start (i.e., Cell OV Warn (3.8 volt) & Cell OV Protect (3.9 volt)). As you mentioned and researching the Cell OV issue, I played with lowering the absorption voltage to 54 and now at 55 volts. However, according to the EG4 BMS_TOOLS software, I am (@ 100% SOC) still having cell voltages getting unbalanced by having at least one cell charging much more than the other cells (usually ~ @ 3.4 volts). Therefore, lowering the absorption voltage to 55 volts has prevented the individual cell from charging to 3.8/3.9 volt and the BMS protection from starting but has not really prevented that individual cell from over charging much more than the other cells.

I paid $10,500 for six EG4-LL (V1) batteries and there is no mention of "Top Balance" or "lowering absorption voltage" in any of the EG4 manuals sold by Signature Solar. I only discovered this issue after establishing battery communication by flashing three of my batteries with Victron HEX file, and it appears the Cell OV has nothing to do with the firmware “I had the issue both before and after flashing the firmware for sol-ark.”

These batteries do not have the smart BMS with auto individual voltage balancing and they should not have been sold by Signature Solar. As you said (see blow), why should they hit 3.90V and trigger OVP and BMS to disconnect, when the default MPPT absorption voltage is set to 56.8 volt (or 56.8/16=3.55 volt per cell). Most people don’t even know this is happening unless they are either using the EG4 BMS_TOOLS software to watch the individual cell voltages or have battery communication and getting alarms.

“The battery doesn't shut off until 3.90V high cell. If you hit 3.90V this will trigger OVP, this will in turn trigger the BMS to disconnect the output and set the SOC to 100%. The battery will not reconnect until the cell drops to 3.45V.”

You just have to go with lower absorbs for now. Like I said, just absorb to something around 54.5V and try to keep your high cell from going much above 3.65V during absorb. So monitor that cell while the voltage is rising during absorb, when the cell is around 3.65V, take note of the pack voltage and make that your absorb setpoint.

Don't bother waiting on SS, you will have your issues fixed before they will have even figured out what's going on.

 

[z_zk_z]

Deleted

 

[Brightside]

I'm not sure why you are using Equalize(used on lead acid batteries), but I'm not familiar with Victron. Just use absorb and set so you don't get OV warnings on the battery keep you high cell at or below 3.65V until you reach 100% SOC(if that's what you want).

You should have a setpoint labeled "Float" on your victron. Looks like your float is set too low to balance your cells. Your pictures show max cell voltage of 3.390V with a 53.600V pack voltage. You can also see no cells are balancing because there is no green square lit up in the lower right corner of your BMS tools.

Your Victron shows Float. So you are in Float with a voltage of 53.60V. You need to raise your Victron Float setpoint up to 54.somethingV to get your high cell/s above 3.40V so it will start balancing.

The battery in "standby" means there is not current going into or out of the battery, as it is in a steady state. If you raise the float slightly, current will be pushed into the battery and raise the voltage.

 

[shopman]

It helps to read the latest battery manual from the manufacturer. You should be charging to an absorption voltage of 56.2v and a float voltage of 54.0v. Do not use the default Victron settings. If you have anything related to equalizing turned on, turn it off as that's for lead acid only and will damage your Lifepo4 battery.

 

[MizzouMookie]

I have some eg4-ll v1 and some eg4-ll v2. The v2 are staying balanced as they should below 0.010mv even at a high soc. All of the v1 batteries have been horribly balanced from day one. Finally I noticed one day they are off by as much as .5v (yes 500mv) it is not possible for them to self balance as they will not start balancing unless the cell is above 3.4v and has greater than 40mv deviation. So I resorted to pulling the batteries outa the rack one at a time and connecting an active balancer to properly top balance them. I bring them up to 54.0v then turn on the balancer and charge with around 1.0amps for up to 56.4 volts which is where I want peak voltage to hit before going to absorbed volts of 54.2. The 4amp active balancer keeps them in check around .002mv deviation using this method. Hopefully this will solve the issues long term as I don’t believe the cells were ever balanced before the pack was assembled. If SS had the BMS password this would all be resolved as the settings could be adjusted to the same as the v2 and it would fix itself over time. But for now this is the quickest option to fix the issue.

 

[z_zk_z]

Deleted

 

[MizzouMookie]

@Brightside and @MizzouMookie thanks for replying and providing information. I want to ask two questions from both of you. When you say “they will not start balancing until cell voltage is above 3.4 volt”, are you really referring to SOC being close to 100%??? I am asking the question because all the individual battery cells in each EG4-LL V1 are balanced within 0.002 volt when the batteries are either charging or discharging AND SOC is less than 98%. 2nd question: Are you also saying that in the future, I could increase my Absorption voltage to higher than 54.8 volt (see below) because the cells are more balanced (behaving better) and they will not hopefully overcharge to 3.9 volt (62.4 volt=3.9*16) and activate the Cell OV alarms? Please keep reading…


@Brightside I followed your instructions and increased my float voltage to make the individual cell voltage to go above 3.4 volts.
Your Victron shows Float. So you are in Float with a voltage of 53.60V. You need to raise your Victron Float setpoint up to 54.somethingV to get your high cell/s above 3.40V so it will start balancing.
@Brightside I followed your instructions and the Absorption voltage of 54.8 volt would keep the cell voltage from going higher than 3.65 volt.
You just have to go with lower absorbs for now. Like I said, just absorb to something around 54.5V and try to keep your high cell from going much above 3.65V during absorb. So monitor that cell while the voltage is rising during absorb, when the cell is around 3.65V, take note of the pack voltage and make that your absorb setpoint.
@Brightside I noticed the squares in the lower right corner of BMS_TOOLS software would start turning green ONLY (in Stand By & Charging modes) when the SOC is approaching 100% (>98) AND if the individual cell voltage is > 3.40 volt. Note, the software cycles between all selected battery Packs, therefore it is recommended to have only one battery Pack selected in the upper left corner of the screen.
You can also see no cells are balancing because there is no green square lit up in the lower right corner of your BMS tools.


@Brightside and @MizzouMookie I really appreciate for your inputs and what you have said for me to do and what you have done yourself. I have been watching the BMS_TOOLS software over ten days, and if allowed, a single cell in battery Pack # 3 overcharges to 3.9 volt. If the balancing @ 100% SOC is not going to make this individual cell to behave and overcharging in the future, I hate to say that I may have a bad cell. I have come to this conclusion because as you can see from the posted BMS_TOOLS screen captured (see blow), I now see cell voltages above 3.4 and even 3.5 volt in other two battery Packs but I don’t see their cell voltages keep going up until the Cell OV is activated. In conclusion, I could keep my Absorption voltage at or below 54.8 volt and say enough wasting time, wait for a few months to see, if that cell starts to behave before increasing the Absorption voltage higher than 54.8, disconnect battery Pack # 3 and increase the Absorption voltage to confirm Cell OV alarm will not be activated by battery Packs 1 & 2, etc.

This BMS_TOOLS software screen capture shows battery Pack # 1 cells are balanced within 0.002 volt and the squares in the lower right corner are not green. This is what I normally see in each battery when the SOC is less than 98% and the batteries are either charging or discharging.

View attachment 142104
This BMS_TOOLS software screen capture shows battery Pack # 1 cells at 100% SOC and the GREEN squares in the lower right corner are for cells with voltage > 3.4 volt. The squares turn green (in Stand BY & Charging modes) when SOC is getting close to 100%. As you can see, the cells are behaving and they are not (overshooting) overcharging to 3.9 volt and activating the Cell OV alarm.

View attachment 142105

This BMS_TOOLS software screen capture shows battery Pack # 3. If Absorption voltage is set to higher than 55 volts, the cells # 03 will continue to overcharge all the way 3.9 volt and activate the Cell OV alarm. Again, GREEN squares in the lower right corner are for cells with voltage > 3.4 volt. The squares turn green (in Stand BY & Charging modes) when SOC is getting close to 100%. As you can see, the cells # 03 voltage is already higher than other cells at 3.64 with cell Pack voltage at 54.79 volt.

View attachment 142107

Having completed top balancing mine use a few different methods there is really two options. You have to open the battery up and install an active balancer. Programming it so it will start balancing at say 3.3v then charge battery up as high as you can get it safely not exceeding 3.65v then shut off the battery BMS and breaker and let the active balancer do it’s thing. Repeating till you can get all cells damn near 3.65 at the same time. This worked for mine and they have been fine for the last few days now. The only correct and permanent fix it to replace the BMS from one provided by SS as they need to replace all these BMS as they have no access to the passwords so that’s their solution. But even with that these cells will never balance with 200-300mv deviation. Something to note you can only tell if the cells are balanced when you’re dealing with a high SOC. As the voltage curves are so flat in the middle that one cell may be at 65 and another at 75. You have to top balance this is the balancer I used and it works well and quickly a few hours for the first balance and you can have the battery straightened out in around a day total.

4S-24S 4A Smart Active Equalizer Balancer 6S 8S 10S 12S 13S 14S 16S 17S 20S 21S 22S 24S Lifepo4 LFP/ Lipo Li-on/ LTO Lithium Battery Energy Transfer Equalization Board 1mv Precision Capacitor Balance https://a.co/d/apOEyOG

 

[629658]

I see this forum flooded with OV and balance issues with the EG4 batteries. Why is that? I bought Trophy brand started with 2 and now up to 8. Added in 3 different purchase times 6 months apart so I’ve received batteries from different manufacturing runs. I’ve never seen any of the issues seen with the EG4’s. All of my batteries have come in with balanced cells. I installed them and I have been done. No fuss no muss. Why is everyone buying this brand and it seems continually having to mess with them to keep them operational. Is it the pricing? I just don’t get it. Maybe I’m missing something.

 

[Zapper77]

I see this forum flooded with OV and balance issues with the EG4 batteries. Why is that? I bought Trophy brand started with 2 and now up to 8. Added in 3 different purchase times 6 months apart so I’ve received batteries from different manufacturing runs. I’ve never seen any of the issues seen with the EG4’s. All of my batteries have come in with balanced cells. I installed them and I have been done. No fuss no muss. Why is everyone buying this brand and it seems continually having to mess with them to keep them operational. Is it the pricing? I just don’t get it. Maybe I’m missing something.

1. Just a slow process with a "passive" balancing BMS,
2. the cells weren't balanced (very well) prior to assembly,
3. people fail to use the correct charging voltage,
4. EG4 BMS typically only actives balance when pack volts rise above 54v.
5. The EG4 OEM 18 amp charger voltage isn't adjustable so it pushes new batteries too high and BMS shuts off due to cell OV. EG4 battery type on my EG4 inverters does the same.

Note once the batteries are top balanced you can use the EG4 automatic settings. Prior to that you need to use "USE" Type and manually set the bulk, float to lower levels and gradually increase voltage as the lagging cells catchup.

*I havent fully tested this* I can also push 30 amps plus through my 50% SOC EG4 Lifepower4 Batteries and the BMS will activate balancing with in a few minutes. Doesn't matter what the pack or SOC is. (More testing needed) But having a battery that statts balancing during the lower SOC may enable a faster top balancing. It took months, maybe 40 cycles before my pack was able to reach 55v.

Now that I understand how the BMS works I was able to hit 58v (using EG4 mode) in a few days.

 

[629658]

1. Just a slow process with a "passive" balancing BMS,
2. the cells weren't balanced (very well) prior to assembly,
3. people fail to use the correct charging voltage,
4. EG4 BMS typically only actives balance when pack volts rise above 54v.
5. The EG4 OEM 18 amp charger voltage isn't adjustable so it pushes new batteries too high and BMS shuts off due to cell OV. EG4 battery type on my EG4 inverters does the same.

Note once the batteries are top balanced you can use the EG4 automatic settings. Prior to that you need to use "USE" Type and manually set the bulk, float to lower levels and gradually increase voltage as the lagging cells catchup.

*I havent fully tested this* I can also push 30 amps plus through my 50% SOC EG4 Lifepower4 Batteries and the BMS will activate balancing with in a few minutes. Doesn't matter what the pack or SOC is. (More testing needed) But having a battery that statts balancing during the lower SOC may enable a faster top balancing. It took months, maybe 40 cycles before my pack was able to reach 55v.

Now that I understand how the BMS works I was able to hit 58v (using EG4 mode) in a few days.

So wouldn’t it be preferable to buy a product that doesn’t require this level of attention? I get it for the most technically inclined but given the options for ESS out there why?

 

[Zapper77]

So wouldn’t it be preferable to buy a product that doesn’t require this level of attention? I get it for the most technically inclined but given the options for ESS out there why?

Price point.

 

[629658]

Price point.

So just a cursory look I see 200Ah of EG4 is $3498.00 ($17.49/ Ah) no shipping. 230Ah of Trophy is $3595.00 ($15.21/Ah) no shipping. Just curious why be would do that?

 

[Zapper77]

So just a cursory look I see 200Ah of EG4 is $3498.00 ($17.49/ Ah) no shipping. 230Ah of Trophy is $3595.00 ($15.21/Ah) no shipping. Just curious why be would do that?

$3K for 2 of the LifePower4 48v

 

[629658]

$3K for 2 of the LifePower4 48v

Ok $15.00 per Ah then so isn’t it worth $0.21 per Ah to buy a battery that works without all the issues? I mean from a time spent, size and wire connection expense still a significant savings with the Trophy’s. Just my opinion but if I had to go through the issues I consistently see with the EG4’s I’d move to something better suited to my needs.

 

[Zapper77]

Ok $15.00 per Ah then so isn’t it worth $0.21 per Ah to buy a battery that works without all the issues? I mean from a time spent, size and wire connection expense still a significant savings with the Trophy’s. Just my opinion but if I had to go through the issues I consistently see with the EG4’s I’d move to something better suited to my needs.

Another reason I didn't pick Trophy was the height of the batteries would have limited me to four batteries per rack vs 6 with EG4.

 

[629658]

Another reason I didn't pick Trophy was the height of the batteries would have limited me to four batteries per rack vs 6 with EG4.

Well to each his own but every connection is a potential issue not to mention the wire expense. At least the way I wire. I just installed 4 additional batteries and spent close to $400 for wire and supplies. So in my way of thinking less is more. You would require 18.5 of your batteries to my 8. Not even mentioning the potential for electronic issues 10 more BMS’s etc. I don’t count any of that as an advantage. I guarantee that 18.5 of your batteries take up much more room than my 8. I’m still curious to know why many of you wait on hold to SS for hours, have to mess with your new batteries for hours to get them operational line up in droves to buy them. Of all the different batteries available and in use out there this forum has 10 times the posts with problems with the EG4 batteries. I just don’t get it.

 

[629658]

If I were a newby and going through the EG4 problem posts it would be at the bottom of my list. I will admit they probably have more batteries out there in use but not enough to account for the number of problem posts.

 

[Zapper77]

If I were a newby and going through the EG4 problem posts it would be at the bottom of my list. I will admit they probably have more batteries out there in use but not enough to account for the number of problem posts.

I have no desire to encourage anybody to purchase from Signature Solar. You can view my negitive post/review on the EG4 6500EX-48 inverters. (BTW SS never published my review) I purchased my equipment July 2022 before the influx of new customers.

 

[Zapper77]

If I were a newby and going through the EG4 problem posts it would be at the bottom of my list. I will admit they probably have more batteries out there in use but not enough to account for the number of problem posts.

The original paper user manuals that were sent with equipment were garbage. They omitted details about correct dip switch settings, correct voltage charging, they had no clue that dip setting zero wouldn't work with BMS Test software, they failed to explain the need to top balance with a lower voltage and that the EG4 default charge settings would just pop the OV cell setting in the BMS before even reaching 54v...BTW the BMS typically wouldn't start balancing until the pack reached 54v. Don't get me started on the flicker issue with their inverters.