3.50~15 Modification Pylontech

[nicolas.huillard]

So I guess that you were not happy with current non-beta Venus OS which does something like this (full-day graph, that’s 8h+ at 3.51V):

I now understand how this behaviour is not good for the longevity of the packs, and I’m eager to install the next stable version in this other system

[Dirk_S]

Yes, the voltage is fine for fully charge and also the cells are well balanced. But I will not keep them for 8h at this level. I charge them much slower and keep them for max 1h at 100% Soc. After that I disable the charger. This is my way and I balance only twice per month. My capacity is high enough. I need around 30 to 40% capacity during summer. If I would need more I would control the charger and batteries in a different way, of course.

[microcheese (Ernst Reiter)]

Hi,

since the Beta 15 my System shows as well a behavior I cannot find a explanation for it. The SoC (as metioned on posts above) gets to a maximum of 94% on the Victron display. Therefore mounted the Console Cable of my Pylontechs and tried to get the Values directly from the Pylontechs as well (2xUS5000). The result is as following:
Victor Shows 94%
According to the Pylontechs, the SoC is: 98.9 and 98.5
See graphs below. Is there any explanation for that? During the Day (Charging/Discharging) - the Values does differ as well (around 2%).

I added as well a picture of the cell voltages if that’s important for this question.

Ernst

[alexpescaru]

You have a quite “lazy” cell in the Pylontech 1. That red one…
Either defective or the pack is not well balanced for quite some time.
This may get the aggregated SOC out of sync.

Try to use the system only with Pylontech 2 for a day or two and see if the SOC is in sync.

Also see that the latest beta has an improved algorithm than the beta15
Use the current beta 25.