Saturday, November 12, 2011

Ooh, Ooh, It's Nearly Running

All wired up and no place to go
Battery pack with BMS chips installed
I spent a bunch of time over the last two weeks finishing up all the wiring for the battery packs, motor controller and the BMS (battery management system).  It's all up and running now.  I turned the whole system on--relays clicked, inverters hummed and nothing started burning--whew.  In spite of my careful checking and double checking of the wiring, I still was a bit worried when I flipped the breaker for my battery pack.

Brains of the BMS wired up
Theoretically, I could open the garage door, turn on the key and drive the truck out into the street today.  It would be slightly less than street legal since it currently has no hood, bed, tail lights, or license plates installed (minor little details).  However, that's not what's stopping from taking a quick emissions free spin around the block.  Before I actually power up the electric motor, I need to program the BMS, charge the batteries and make sure the system is working properly.  Failure to do this correctly could result in damaging the $8000 battery pack.  So I'm now working on programming the BMS. I was successful in getting the BMS powered up and connecting to it's computer via my laptop.  Unfortunately that was the limit of my success this last week.

We're engineers, let's be obtuse!

Snapshot of BMS data
I'm an engineer (civil engineer not electrical or mechanical) and I hate it when engineers write a technical document that can only be understood by the engineer who wrote it.  The BMS "manual" at the Elithion web site is just such a document.  I think most of the information I need is on this site, but it's not easy to find and when I find it it's often a very broad instruction that you can't complete without more information, or there's a ton of detailed information but no specific instructions on how to complete the task.  

Here's one of my favorite examples.  The setup page of the instruction manual tells you that "Many other parameters may be customized, but usually they are left to their default" with no further information on how to determine what you need to change and what you can leave at it's default setting.  One group of "other parameters" that you have to set are the information that the BMS uses to determine the state of charge, i.e. how full your batteries are at any point in time.  If you hunt around long enough you'll find two other pages, each tens of screens long, that I think may have the information I need to set these parameters.  It will take several hours of deciphering and a few phone calls to be sure.  

The Elithion BMS is definitely not a Mac.  It's a long way from plug-n-play and the company seems to like it that way. I've read a few posts by one of the Elithion engineers on several EV forums.  These guys are a lot like bad IT support folks.  They're way smarter than their customers about how their product works--duh--and they pride themselves in pointing out just how stupid their customers are--not a good way to get new customers.


  1. Hello WAK,

    I understand your frustration about the breath of information that one must understand in setting up a BMS of such flexibility and comprehensiveness. Indeed, about 20 % of our clients feel overwhelmed, exactly as you do. (Another 20 % are ecstatic about having access to all that info, and the rest seem not to have any opinion either way.)

    But, fear not: with your permission, we'll do the complete set-up for you, and you won't have to worry about a thing.
    Just contact us ( and our tech support engineer will access your BMS (with your permission) through the internet, and do the complete set-up for you. Easy!

    Looking forward to hearing from you,

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  3. Davide,
    I'm quite pleased with the Elithion BMS. Getting it setup has been more frustrating that I think it should be. I think the online manual is probably a good reference document, but it isn't a particularly good installation/setup document. I also think it would be helpful to have a good printable copy. I've read your comments about how the online version is better, but I disagree for a number of reasons. Mostly because I find it very difficult to try and work with my laptop in the shop. I've had to print out all the sections I need to use so I can easily read them while working. I can toss a piece of paper on top of the battery pack to look at while I'm wiring something up, but tough to do with a laptop.

    By the way, I'm an engineer (though not an electrical engineer) so I think I should be able to figure out how to install and setup your BMS by reading the manual without a bunch of hand holding and telephone calls. I am a novice to EV conversion, but I expect many of your customers are. I think you should be able to write a manual that intelligent novice can understand and still have all the details needed by an expert.

    I've been in contact with Robert and he's been quite willing to help get the system setup. He was going to help me yesterday but I needed to troubleshoot a problem with my load side current pickup. I fixed that tonight so I'll get with Robert next week and double check my setup. I appreciate this kind of service.