BMS for open revolt

[Grimm]

Thought I'd pass this along - Power line DC-BUS communication applications...
Look on the bottom left under "DC-BUS in Renewal Energy"

[bennelson]

It isn't a BMS, but lately, I have been using a simple battery monitor a friend designed.



It's an LED bar graph that shows the voltage of each of four batteries. (This one is a double, it will do up to eight 12V batteries.)

Using it, I was able to spot that one battery always started dropping voltage faster than the others. I replaced it and the car seems to be performing better since then.

[sawickm]

Originally Posted by bennelson

It isn't a BMS, but lately, I have been using a simple battery monitor a friend designed.

Ben,

Any more info or documentation that you can share on that battery monitor ?

-Mark

[bennelson]

I'll post some more info on that project soon.

I haven't actually been one to do the soldering on one of those yet, but I have some video about it that I need to edit and post.

[The Toecutter]

Any idea when this is going to be available for sale?

Is there anything I can do to help with its design to speed it along?

I'm currently planning a crude system that will use zener diodes and lightbulbs to bleed off excess charge current, but it will do nothing for discharge. No BMS will kill AGMs in a few thousand miles.

[bennelson]

I think we are in the testing stage right now for these battery monitors.

Next time I see Tom, I will ask how close he thinks we are to being able to sell a version of it.

He's an EE, so he knows what he's doing for making them. It's more a matter of features on it and getting some EV miles of testing on them.

[1-ev.com]

What do you guys think about this BMS:

minibms.mybigcommerceDOTcom/pages/Product-Support.html

Prices are here:

cleanpowerautoDOTcom/MiniBMS.html

minibms.mybigcommerceDOTcom

[Tired2]

Paul,

Just a thought on CAN... OBD-II is a CAN system if I remember correctly. I'm not sure what all information is there other than stuff related to the old engine, but if most converters of newer (OBD-II) cars keep the ECU, you can pull speed sensor value and probably 12v battery voltage from there at least, maybe more. Just something to think about.

[isaac_alaska]

those mini bms seem pretty expensive if you're planning a very big pack... i don't know a whole lot about bms yet but i would think that a scalable circuit could be designed for maybe a dollar or two per cell, rather than 12 dollars per cell plus master boards at 230 dollars per 16 cells. again, i might be wrong, or maybe i'm missing something.

[sawickm]

Originally Posted by isaac_alaska

those mini bms seem pretty expensive if you're planning a very big pack... i don't know a whole lot about bms yet but i would think that a scalable circuit could be designed for maybe a dollar or two per cell, rather than 12 dollars per cell plus master boards at 230 dollars per 16 cells. again, i might be wrong, or maybe i'm missing something.

The MiniBMS started as an open source project. This is the link to the development of MiniBMS: MiniBMS Project

Regards,

-Mark