[Feature]: When target is 98 or 99 then make target 100% and keep charging at CVL (and respect CCL) to allow for balancing

[SimonYoungtree]

Contact Details

siempoot@gmail.com

Description

When target is 98 or 99 then make target 100% and keep charging at CVL (and respect CCL) to allow for balancing.

I could inject the 100% myself (via Node Red) when the target is 98% or 99% to override things. However the charging will not keep pushing to the CVL the way things have been implemented at the moment. So currently this workaround does unfortunately not work.

Suggested Solution

When target is 98 or 99 then make target 100% and keep charging at CVL (and respect CCL) to allow for balancing.

Alternatives

Until solved: manual intervention (disable DESS and set schedule to 100% for a number of hours) once per month to do some balancing.

Additional Context

No response

[MichaKersloot]

Just a question, is your system only balancing on 100% SOC? My pylontechs seem to balance when one of the cells is over 3,45V independent of SOC. Furthermore there are settings about absorption, float and sustain in veconfig. Maybe that is the place you can finetune the settings to your need.

[SimonYoungtree]

My system currently starts balancing at 3,5 volt when any cell reaches this voltage. The bms moves to 100% when balancing is done. And that works perfectly when normal ESS tries to reach 100%, as it goes up to CVL. There is no guarantee that 99% will reach 16*3,45V either. 54V (3,375V per cell) is also 99%.

I have a rule on node red that moves CVL to 54V (on the GX device) after 2 hours having reached 100% for the first time. (And back to max CVL when 95% has been reached. To avoid unnecessary pushing the battery.)

About the settings in veconfig: they are ignored when using DVCC. Also the PV charger uses the DVCC settings.

[MichaKersloot]

If you want to control this yourself instead of the BMS (which sets the CVL, CCL and DCL, I presume). You are maybe better off not connecting the BMS to the victron and use a shunt for SOC monitoring?

[SimonYoungtree]

I just want the charger to do its work: charge up to CVL

Op wo 1 nov. 2023 15:05 schreef Micha Kersloot @.***>:

If you want to control this yourself instead of the BMS (which sets the CVL, CCL and DCL, I presume). You are maybe better off not connecting the BMS to the victron and use a shunt for SOC monitoring?

— Reply to this email directly, view it on GitHub https://github.com/victronenergy/dynamic-ess/issues/113#issuecomment-1789016304, or unsubscribe https://github.com/notifications/unsubscribe-auth/BBFKQDBKERVGWN4OJIYSJZDYCJJJFAVCNFSM6AAAAAA6WB46D6VHI2DSMVQWIX3LMV43OSLTON2WKQ3PNVWWK3TUHMYTOOBZGAYTMMZQGQ . You are receiving this because you authored the thread.Message ID: @.***>

[SimonYoungtree]

I will build a workaround with node red: every hour I will check: when DESS has a target of 98% or 99%, I will turn off DESS and switch back to ESS for 55 minutes (or so) while injecting a charge schedule for one hour to 100%. After 55 minutes, I will turn DESS on again to allow it to refresh its calculation. And then it repeats itself.

Or maybe easier: I will setup continues charge schedules in ESS to 100%. They are ignored when turning on DESS and become active again when switching to ESS. --> No need to inject a schedule for an hour each time.

[dirkjanfaber]

You could also add a function in just before the 'split schedule 0' function that contains:

if (msg.soc >= 98) {
    msg.soc = 100
}
return msg;

[software-testing-professional]

Hi guys,

I'm a bit late and just found this issue closed.

@dirkjanfaber Can you please reconsider this issue, and maybe reopen it?

I have a ESS with 3x MultiPlus2 and an AutarcTech 11.2kWh battery. This battery has an active balancer (AutarcTech Joulie-16) - and it's always balancing, and not only at 100%. And I'm currently using the DESS via VRM Portal (no Node-Red). Also DVCC is used (via Node-Red).

BUT: My BMS calibrates the 100% SoC only when:

• at 54.8V and
• at no charge for at least 5min

So if my battery never reaches 100% SoC for quite a while, it's not good for calibration.

Could you please add some logic to have the battery fully charged at least once a week or so? Maybe I'm not the only one with a need for 100% SoC from time to time...

Thank you, Michael