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teddillard
17 June 2011, 0423
wooHOO! Gene ("Skeezmour"... and more importantly, his lovely wife Jen) came over last night for simply the best BBQ available in the Northeast (courtesy of my lovely wife, Teresa), and left (OK I kind of hid it, then plied him with some local brew to make him forget it here...) his demonstration kit of the Manzanita MK3 BMS. After messing with it a bit this morning, I've decided to do a full write-up over the next few days...

Here's what the 4-cell (surface-mount) module looks like.

http://evmc2.files.wordpress.com/2011/06/picture-31.png?w=640&h=423

Playing to my strong suit (basic lack of knowledge and experience with any BMS, other than reading about how they tend to melt with remarkable regularity), I'll be going through all the steps of setup from a basic noob perspective. Let me know if you have any questions, if I can answer them I will, if not, I'm sure Gene will chime in.

I'll update here as I can, but the main post is here:
http://evmc2.wordpress.com/2011/06/17/review-manzanita-mk3-bms-part-1/

Skeezmour
17 June 2011, 0614
I was wondering where that gear ran off to :)

Great BBQ BTW!

Allen_okc
17 June 2011, 0645
Ted you Dog - im jealous... congrats, and i definitely can use some educating on the bms system...

teddillard
19 June 2011, 0358
OK, got the Documentation section up this morning:
http://evmc2.wordpress.com/2011/06/19/review-manzanita-mk3-bms-part-2-intro-and-documentation/

Can I just say- all the manuals have, on the last page, no less than Rich Rudman's name, address and phone number. I don't think, of all the tech documentation I've read, I've ever seen that kind of personal commitment to a product like this. Rich deserves a big shoutout for that, alone... :D

teddillard
19 June 2011, 1551
aaaaannnd.... a rundown on the Display:

http://evmc2.wordpress.com/2011/06/19/review-manzanita-mk3-bms-part-3-the-display/

http://evmc2.files.wordpress.com/2011/06/regbusdisplay2.jpg?w=640&h=437

teddillard
20 June 2011, 0345
"The Board" is up:
http://evmc2.wordpress.com/2011/06/20/review-manzanita-mk3-bms-part-4-the-board/

teddillard
21 June 2011, 0402
Here's the bit on the SOC Head:
http://evmc2.wordpress.com/2011/06/21/review-manzanita-mk3-bms-part-5-the-soc-head/

This is really getting interesting... First, the SOC head is where you can get into some really specific programming using their software. You also get access to several relay circuits, so you can build in cutoffs and turn-ons at certain events. Using this, for example, Gene suggested you'd use a throttle cutoff to shut the pack down at a low-voltage point.

I bet you could set it to play "Ride of the Valkyrie" at high amp draw, huh?

Besides that, this is also where it dawned on me that the entire system is built on the idea of several components that can run in stand-alone mode, but when you plug 'em together you get huge leverage... I needs me a spreadsheet, think that's coming next.

Edit: quickie spreadsheet:
http://evmc2.wordpress.com/2011/06/21/review-manzanita-mk3-bms-part-6-component-matrix/

teddillard
22 June 2011, 0359
Wrapup: This thing ROCKS (short version).

Long version:

Somewhere along the way in this review it dawned on me I was working with simply the best BMS system available. There. That’s my conclusion. Please remember this is the first working BMS I’ve looked at, so it’s been a great learning process, and also note I said BMS system. The Manzanita is a complete system-based concept of not only battery management (including charge management), but cell, pack and overall data logging. I went back and looked at other products available, and there simply is nothing out there like it.

I’d love to be in a position to test the reliability and function of the system, but there’s just no way I can do it. However, you can take a quick look at who’s using it and judge for yourself. It’s a big list, but if you narrow it down to motorcycles, it’s a list with names you’ve heard before: Chip Yates. Killacycle. Motocycsz. I could go on, but I risk talking out of school… I’m not sure what the sponsorship/support arrangements are… They’ve cut their teeth building systems for cars, systems that are simply the highest performance packages out there. You can bet that, if you’re tapping the Elemental Forces to power your motorcycle, the Manzanita BMS system is going to be the most bulletproof system you can get. Yes, I’d love to get my hands on one and try to break it, but honestly, I can’t imagine doing anything to it that, say, Chip Yates hasn’t already tried to do…

It’s clearly a pricey system, but you can’t even say pricey compared to any real product. The closest package out there is the Elithion BMS, and it doesn’t have the same features or functionality. The other products available, probably the “Mini-BMS” is one of the more popular, may be great products, are a lot cheaper, but are simply not in the same class. To get similar features you have to combine them with other products, like the Cycle Analyst or CellLogger.

Besides being a great set of features, the MK3 is built in the US, and it’s built by the folks at Manzanita… not some off-shore manufacturer. I’ve been told they use all the highest-grade components, and I have little doubt that’s true. In electronics, price = reliability, period.

So, bottom line? I’m sold. When you consider the cost of your batteries, the fact that you may change out your battery systems and need some flexibility in this investment, and the cost of your whole effort (as in building and racing a competition bike), as well as the notoriously bad reputation the BMS has as a point of failure, it seems to me that a system like this is where you need to suck it up and put your money- hobby builder or not.

Stuff I learned.

OK, I’m going to show you this shot at the risk of freaking Gene and the boys at Manzanita out…

http://evmc2.files.wordpress.com/2011/06/picture-13.png?w=531&h=410

…but this, my friends, is just what a BMS is designed to alert you to, and keep you from doing to your cells. I set up a little drain test using my headlight and kept an eye on it for a while. I then went in to make a cup of coffee, and came back to this display. This shows a couple of things… first, it underscores the fact that voltage in a lithium cell is a bad indicator of SOC (state of charge). The cell was showing lower than the others when I went inside, it dropped of the cliff in about ten minutes.

Second, it demonstrates one key point you need to understand about a BMS, that I did not understand. There is no BMS out there that will shut off a cell if it gets dangerously low. It’s simply too hard to do, considering the current the cell is handling, but used properly, you can set the BMS up to cut out the throttle or controller if the alarms are triggered. I thought, mistakenly, that the thing would shut out that cell by itself.

It is, however, a great example of how the display works to show both the relative cell levels as well as their session history. (I only pray that Gene doesn’t look too close at the low voltage on that #1 cell… yes, my friends, you read that right. .739V. I may have bought my first Headway cell… )

Other stuff I learned? Basically, if you want a BMS, there are a lot of smaller, cheaper products out there that will simply balance cells. If you want an integrated BMS system, this is the only one, and a damn good one.

Conclusions?

Besides everything else, I want to underscore the support and accessibility that Manzanita has demonstrated. If you’re a race team using their products, you have about a 90% chance of seeing Gene Seymour show up at the pits to check in on you before the race. It’s a small company, and the literature doesn’t have the polish and glitz of a product from Apple or Sony, but you get the information you need in a good, concise package. If that’s not good enough for you, you get the phone number of the guy who runs the company. Game over.

In a landscape where you need a good, reliable and affordable BMS to protect your (huge) investment in lithium, it’s been a situation where there has simply been no complete, turnkey system available, until this. This system clearly sets the bar.

There’s talk of some increased functionality coming down the road- SmartPhone interfaces, enhanced programability, like that… but at this point I haven’t heard any rumblings about any lower-priced systems, and I don’t expect to. When the manufacturing scale ramps up, we may be seeing some price drops simply from production scale, but that’s just conjecture. …but my final word? A+, and worth every dime.

(original post here: http://evmc2.wordpress.com/2011/06/22/review-manzanita-mk3-bms-conclusions/)

Allen_okc
22 June 2011, 0643
Manzanita Rocks - i like the folks there...

DaveAK
22 June 2011, 0957
Glad you've finally caught up to the rest of us Ted. :D

A complete system is exactly what I'm trying to accomplish in my little corner of the world. Unfortunately I don't have the money, time or expertise of the guys at Manzanita so my efforts won't produce such a polished product, but it should do everything there's does and maybe more.

teddillard
22 June 2011, 1101
ooooo. You're so smAAARt. :p

It was a great chance to actually see the parts and pieces, and how they work together...

Basically, after reading post after post about BMS failures and associated BMS-related BS, and not really ever reading a post that started with the assumption that I didn't already know what a BMS was and did, I learned a whole lot by actually seeing the parts. (Hopefully someone else can, too.)

...and, THANKS Gene! (Even when I melted his battery, he patiently answered my dumb questions...)

BTW, it was also news to me that virtually all the "big boyz" are running the Manzanita...

DaveAK
22 June 2011, 1144
There's a lot to be said for seeing it all work together, and getting it all to work together seemlessly. I hope that my endeavours at least come close in functionality, if not in quality of product. This is the stuff that I'm in to EVs for.

teddillard
22 June 2011, 1155
Honestly, that one point I learned about the fact that a BMS cannot shut off a cell that is getting near the low voltage limit - was a very simple, and very basic point that had completely escaped me. When people say the BMS is there to protect the cells against low and high voltage, that's what I assumed it did. I saw the little mini-BMS video that showed all the cool lights while the thing was shunting a cell, I assumed it did the same thing somehow at low voltage.

For the record, Gene answered my question about that as if he'd answered it a million times before... leading me to believe it wasn't as dumb a question as I'd been afraid it was. Either that, or he was experiencing "Post Awesome BBQ Glow" :D

Looking forward to seeing your work with the project. Now that I have a clue what it's about. :cool:

DaveAK
22 June 2011, 1207
I think you raise a very good point. I've never understood the whole BMS arguments from either side. If people have limited understanding and they're relying on the likes of forum discussions then they're never really going to gain the knowledge they need. The fact that you learned a great deal from Gene highlights the educational problem and the lack of information or level of misinformation that's out there.

teddillard
22 June 2011, 1223
The other thing I've pretty much decided is, especially if I go with lipo, I'm gonna run the Manzanita. I figure for the small additional investment after everything is said and done (balancing charger, cell-logger, cycle analysts and stuff) I get one package with one (awesome) display, that will give me a lot more confidence that I can manage them touchy things correctly.

(Yep. Just saw the shots fat-tony posted of the Munch bike fire... :O)

DaveAK
22 June 2011, 1318
I've pretty much decided that if I win the lottery I'm gonna do the same. Making this stuff yourself is a fools game. :)

DRZ400
22 June 2011, 1615
looks very nice but also looks like it would cost more than my batterys....mini bms does everything required (lvc, hvc & balance) plus its well designed/made, probably why its so popular. Now if I was doing a car with 40 200ah cells the cost won't be such a factor.