Batrium With Mixed Chemistry Banks

[12ax7]

Hey everyone! I've been doing extensive research and watched pretty much every youtube video you guys have posted.
All great stuff!

I was considering building my own BMS system and came across Batrium.

Here is my question.

I'm going to be running a mixed chemistry environment using 18650 Li-Ion cellsthat I acquire over time in a 40p 14s string to net me 51.8v nominal.
As well I'm going to have another battery bank that will consist of 32650 LiFePo4 cells arranged in a 20p 16s string to net me 51.2v nominal.

The idea is I would just run the Li-Ion bank at 51.2v nominal as well to keep the banks someone in sync with each other feeding a Sigineer 12kw split phase inverter (US)
I can imagine if I don't line the overall capacity with each other I'll need to somehow diode these banks from each other so one doesn't back feed to other after some extensive load.

I suppose thatis for another topic.

But using Batrium can I individually specify the voltage of each cell? Or is it global?
I'd prefer not to have two individual Batrium systems.

Hopefully I'm making sense here, and look forward to me showcasing my project as I go. :blush:

Attached is my initial rough draft for a 14s Li-Ion battery

 

[daromer]

Check out my install. I run LiIon and LiFePo4 connected to each other. What you are doing are exactly what i have been running for quite some time now.

I run 1 batrium for each system. The reason for this is that its actually 2 banks and i want easily to be able to controll them booth on each own terms.

Batrium only have support to set 1 set of longmons at a time even though you could potentially have different configs. Also 1 watchmon can only handle 1 shunt.






No worries about current going back and forth. They will balance as they want.

Also note that you never will be able to utilize full DOD on the Liion bank due to the longer voltage range compare to the rather short voltage range on the LiFePo4 bank.


LifePo4 goes between 20-100% meanwhile the LiIon goes between 30 and 70 at most.

 

[12ax7]

Thank you for the prompt reply Daromer!I've watched a majority of your videos.

That was what I was afraid of with running two different battery chemistries, but $600ish for another setup I suppose isn't that bad.
Regarding your software that runs on the Raspberry Pi that is polling information from Batrium correct?
And from there you are using that dashboard to display data from both Batrium units onto a single dashboard?

I still have some substantial studying up to do.
I've already decided to revise my battery packs into a single row consisting of 14cells in series with 80 18650 in parallel per cell string. This will enable me topiggyback additional cell strings in parallel later on. However I'm not certain having 160 batteries per cell is a good idea.

But that is a topic for another thread.

Thank you!

 

[daromer]

You should not have to big packs in terms of capacity if you want to be able to keep them balanced without issues. In long term its wise to keep them down if you can. 200-400Ah is generally a good max for many systems per pack.

The ISO that i put together is what I use. There is a big update on its way for that one that contains autostarting software among some things.