Victron MP2 mit Pytes E-box 48100r-c Ladeverhalten

[Sudybua]

Servus,

Konfiguration:

-3 Mp2 3000

-4 Pytes E-Box 48100rc

Habe das Ladeverhalten meiner Pytes Batterien einige Tage beobachtet. Mir ist aufgefallen dass das Pytes Bms eine CVL von 55.5V schickt und dann solange lädt bis der Speicher komplett gebalanced und voll ist. (Soc bei 99%)

Danach geht der Mp2 in Entladung. Bei ca. 56V triggert das Pytes BMS die 100% soc. Die Batterie entlädt dann bis ca. 54,4V. (Soc 98%) und lädt dann wieder auf die 56.5V.

Wenn ein schöner Tag ist macht das System diesen Vorgang 3 mal.

Frage:

Ist dieses Verhalten normal? Warum komme ich nie in Float? Ist es besser die Batterie nur bis 55,2V zu laden und dann dort mehrere Stunden sitzen zu lassen?

Lg Daniel

[MikeD (Mike)]

For lithium batteries, float is not really necessary, except for those cells used in a UPS type application.
The charging characteristic is determined by the CVL and CCL provided by the BMS, so if you are seeing this cyclic behavior, then it would appear that your BMS is operating a type of float / recharge cycle, from 98 - 100%. It would be interesting to observe what the CVL and CCL limits sent by the BMS to the cerbo are during this cycle.

[MSl1]

Have a look at these values.

@Sudybua

Ist dieses Verhalten normal?

I think, YES. Here is an example (Home Assistant Logs incl. DVCC values) of my Pytes V5 stack. The batteries are similar.

The Pytes BMS does simply his job.

(Addendum: And think on it, the gx device takes 15-20W from the batteries, so the BMS start charging after a lower SoC threshold is reached.)

[Sudybua]

Thanks for your reply,

I think you are right. In my system the solar is connected to Ac-In.

My brother have his solar on the Dc side with victron mppts. In his system the battery goes into float and stays there until evening because the load needed on the Dc side comes from his mppt.

I thought its not good to charge that often in such a high soc.

Best regards Daniel