question

spinkb avatar image

1560Ah 48v lithium 3-phase quattro 48/15000/200 x3 battery config 82kWh

First, I've read countless articles trying to self resolve my issues. The vast majority seem to be people using very small systems...and my issues seem to be different. Or other people have bluetooth connectivity to their MPTT and I don't...so not sure if I need to get a USB cable and connect, or I can do things online.


Two issues I want to solve.

1.) Low battery alarms are useless. I want them off, but I can't seem to stop them. My battery is at about 44% (46v), and the alarms are configured for 25% and I continually am getting non stop notifications. VictronConnect on my BMV700 I don't think is related to this, and I have alarms disabled on the remote console...so what is sending these alarm emails so I can stop it? Or at least get it to somehow respect what 25% actually is instead of it having some other calculation its doing.


2.) I cannot get the battery settings correct in VictronConnect on my BMV700. I have to keep monitoring the percentage as it keeps getting off a little. Battery capacity is set at 1560Ah which I know to be correct. 13s13p packs with EIG 20aH cells = 260Ah...with 6 of these in parallel = 1560Ah. I've read for Peukert that its effectively close to 1.00 for Lithium...and especially considering how large my capacity is, my batteries never get any stress at all. So I am actually using "1.00" currently. I've been testing that at 1.00 to 1.09 with equally confusing results of not calculating the correct percentage based on voltage. I'm wondering if I need to toy with the capacity value to get one that helps make the SOC follow correctly...


Help or guidance on how to properly set the config so it follows reality on the batteries? Attaching screenshot of the config currently along with battery specs.


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Lithium Batterybattery chargingSOCalarm
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6 Answers
Paul B avatar image
Paul B answered ·

This is my opinion on SOC, Its a inaccurate flow meter - as every battery bank has its own parameters and most people just leave the default settings in the BMVs and thus the SOC needs resetting often.

you have to fine tune the battery settings to get it correct SOC and again it changes as the battery ages. VOLTAGE IS always correct (yes you may have to read it when there is NO load or charge for 30 min to 1 hr, for it to be very correct but its always close)


Re You Issue 1

WELL my suggestion is you FORGET SOC, ONLY USE voltage as the base referance - Voltage is the king of it all. it DOES not matter what the SOC says if the voltage drops then the battery is Discharged

so reconfigure to mainly use voltage with a reference to SOC.


Re Item 2

set the BMVs charged voltage setting to the normal fully charged voltage for the battery and then the SOC will reset to 100% when its reached.


Also look up the standard voltage charts to SOC will give you more of a idea as the voltage of the battery bank then tells you the SOC level this is the same for LA and lithium banks

So please always look at voltage and compare it to the charts then to your BMV SOC reading if its out all the time then slowly do adjustments on the BMV to the appropriate settings


you should always try to bring the bank upto the fully charged figure at least once a mth so the SOC reset is done and the batteries BMS has a chance to balance any out of balance cells

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spinkb avatar image
spinkb answered ·

I've not seen any config that allows me to change how it does that... And yes, I agree voltage is really all that matters. But nowhere allows me to set the min voltage...in my case, 39v. That is 15.6v of usage area between 39.0v and 54.6v. (3.0v to 4.2v as per the spec sheet.) So I calculate my own manual percentage based on that value...however, I need to ensure it never goes below 3.0v per "cell"...


This should be a simple calculation in my opinion...purely based on voltage, if its under load, the percentage could be offset a little due to the load, and if its under charge, the opposite adjustment of percentage, etc. The Ah of the battery is irrelevant, just the min and max voltage matters. Balancing the cells should be done at any point desired, not only at 100%, etc.

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The 3 volts per cell is ONLY controlled by you BMS as that monitors cell voltage then it should signal the quattro to turn loads OFF, but leave charging on,

some batterys have inbuilt BMS cutoffs and if thats the case then theres not much that the quattro can do

Paul B avatar image
Paul B answered ·

what assistants have you got installed

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Paul B avatar image
Paul B answered ·

there are three spots one in the ve config program under

The other is in the PV assiatnt or the ESS assistant these ess ones OVERRIDE the setting set in the Inverter section

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marekp avatar image
marekp answered ·

My suggestion.

Do not charge this battery to 4.2V per cell. This is the max that should never be reached if you want this battery to last.

Set your max cell voltage (absorption) lower (4.0V) and when battery gets there the SOC will be set to 100%.

Your battery will thank you for it with longer life span.

I would make this battery pack 14s12px6 because that will be closer to LFP battery voltage range.

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spinkb avatar image
spinkb answered ·

I can't redo the battery build...that its done.


I don't have a windows laptop to connect via USB...so my control over the system has only eben via the remote console, and via the BVM700 config using VictronConnect. nothing else is available for access. So I am guessing to do the config items you are referring to I will need a laptop and USB cable to get to those...

Gotta get a laptop I can use to run VE Config. :( I've got M1 MacBooks which can't run windows sicec they are ARM based. Might have an old laptop laying around that can still run windows... I guess that is a requirement for any other configuration. Nothing else can be done remotely...?

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If you have VRM set up, you can do remote VE config.

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