Open BMS for high voltage LiFeP04
 

Hi all,

I have been reading Ecomodder for quite a long time, however never posted here.

I am converting a car to electric and I am using a DC BUS Voltage of 600VDC.

I will have a string of 192 LifePo4 Cells and I am looking into a decent BMS that allows me to check the status of the batteries, like lower and higer voltage cells, etc.

I am happy with 4 arrays of 154V.

I have looked into the Open Revolt BMS project but I cant find a lot of information on where to get the PCB´s. They are also made to fit large 100Amps batteries. As I plan to use 10 or 20Amp Cells I would like a central BMS, instead of a battery attached one.

Can anyone give me some advice on this?
Thanks, Carlos

Mini BMS does have a centralized design. However, I'm not sure it can handle a 600V pack.

MiniBMS

Paul & Sabrina greatings! & Thoughts to the thread's topic.
 

Hey all,

this is my first post here (still reading through the open revolt threads from beginning to end ...) :snail:. Currently I'm still reading Paul & Sabrina's Open Revolt Controller thread. And, yes, I love it :rolleyes:, the style, the detail, the quest they follow -- I have to say, I'm very impressed. I feel very tiny next to you big kings and queens of green power tech. :)


Okay, so now - let's dive into it - you talked of a string of 192 single cells - each 3.2 V as of LiPO4, isn't it? That was indeed 192 * 3.2 V = 614.2 V.

Now, do you, utilizing as you said 4 arrays - each 153.55 - really split them up such that there would result 4 * 20 Ah = 80 Ah in total?
This was not even equal to one of Paul & Sabrina's 100 Ah battery management system ratings, thus you could use their distributed design for your centralised one. Though I doubt, 80 Ah would be enough to drive a distance big enough to me.

Assuming a continuous current draw of 240 A, you would not even get 1/3 h = 33 min of driving time. Not that it is not enough to reach the next city. But to be more flexible? I would be afraid not to find any chance to charge and surely I (or at least my bones) will not like carrying a bunch of solar panels with adequate specifications for a proper recharge of the EV "on the field" with me all the time, when driving.

I'm not sure about what you mean with bus voltage - but is it really 600 V? 4 arrays, 154 V each, in parallel will not heighten the voltage, but the capacity. Thus there was a resulting voltage of 154 V for the BMS to handle, wouldn't it?
And that's why I think the Open BMS of Paul & Sabrina would do it.


Tell me if I'm wrong. Perhaps I misunderstood the count of cells you want to utilize.


Regards to all you ecomodders,
Jon Ardaron :rolleyes:

(I will go on reading ... :snail:)