Deye Battery Type: Bat% Mode

[drakejest]

I installed a solar system for a client and i have given them access to the app. They do not like how that the battery SOC is represented as voltage, i had always done it this way because it gives me full control of the batteries. But my client does not like this, understandably so as they are not technical people. They would rather see it in SOC percentage form.

The Deye inverters has 3 battery modes: Voltage mod, percentage mode, and Lithium mode (inverter talks to the BMS).

Voltage mode is already out of the question, the ideal case would be lithium mode, but the BMS of the battery is very weird, the batteries would suddenly start charging from the grid in the middle of the night at around 20% even though grid charge is explicitly disabled on the inverters.Client and me doesnt want this, we never want the batteries to be charging from the grid.

Now all thats left is the percentage mode. In this mode i cant find a reference on how this works, how does it calculated the %. I tried it and it does not properly track the SOC for example inverter say 50% but the battery display says 65%, quite far in my opinion. Can anyone please explain to me how deye Battery% mode works?

 

[timselectric]

I installed a solar system for a client and i have given them access to the app. They do not like how that the battery SOC is represented as voltage, i had always done it this way because it gives me full control of the batteries. But my client does not like this, understandably so as they are not technical people. They would rather see it in SOC percentage form.

The Deye inverters has 3 battery modes: Voltage mod, percentage mode, and Lithium mode (inverter talks to the BMS).

Voltage mode is already out of the question, the ideal case would be lithium mode, but the BMS of the battery is very weird, the batteries would suddenly start charging from the grid in the middle of the night at around 20% even though grid charge is explicitly disabled on the inverters.Client and me doesnt want this, we never want the batteries to be charging from the grid.

Now all thats left is the percentage mode. In this mode i cant find a reference on how this works, how does it calculated the %. I tried it and it does not properly track the SOC for example inverter say 50% but the battery display says 65%, quite far in my opinion. Can anyone please explain to me how deye Battery% mode works?

It just calculates it based on voltage.
And displays it as a %.
It will improve with cycling, but it's never going to be perfectly correct.

 

[drakejest]

It just calculates it based on voltage.
And displays it as a %.
It will improve with cycling, but it's never going to be perfectly correct.

Im fine with maybe 5% error but 15% is a bit much. If i let it run for a while around how many % is the average error rate do you think it will have? just for reference so to set expectation if the accuracy gets better or not

 

[timselectric]

Im fine with maybe 5% error but 15% is a bit much. If i let it run for a while around how many % is the average error rate do you think it will have? just for reference so to set expectation if the accuracy gets better or not

Nothing exact. Just have to see how it goes.

 

[timselectric]

It will be more accurate, if it reaches 100% daily.

 

[drakejest]

Nothing exact. Just have to see how it goes.

Okay thanks ill observe it for a couple of days, hopefully it turns out to be accurate enough.

Thank you so much for your advice

 

[drakejest]

It just calculates it based on voltage.
And displays it as a %.
It will improve with cycling, but it's never going to be perfectly correct.

Is the Battery Empty Voltage setting taken into consideration in the calculation of the % ?

 

[timselectric]

Is the Battery Empty Voltage setting taken into consideration in the calculation of the % ? View attachment 320643

I believe it would be.