# New BMS acronym



## Russco (Dec 23, 2008)

jddcircuit said:


> I just read Jack Rickards EVTV.me blog.
> I thought the Battery Masturbation System was hilarious.
> 
> 
> ...


I believe behavior of this sort will cause the car to go blind.


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## Siwastaja (Aug 1, 2012)

It never stops amazing me how some people take this guy seriously.

Another thing I'm surprised at is how anyone has time to watch his 2-hour videos that mostly contain chit-chatting with a few minutes of actual data in the middle, hard to find without fully watching the show.


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## onegreenev (May 18, 2012)

Well then who do you suggest we listen to, you


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## onegreenev (May 18, 2012)

Who else has stepped up to the plate and put his money and time and expertise into hping others and motivating others to join in. He knows what he talks about.


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## EVfun (Mar 14, 2010)

Siwastaja said:


> It never stops amazing me how some people take this guy seriously.
> 
> Another thing I'm surprised at is how anyone has time to watch his 2-hour videos that mostly contain chit-chatting with a few minutes of actual data in the middle, hard to find without fully watching the show.


I agree, his videos are are bad as modern television. Perhaps 10 minutes per hour of actual new content. 

You can run with a BMS or without a BMS. Either way, the devil is in the details.


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## Siwastaja (Aug 1, 2012)

onegreenev said:


> his money and time


Well indeed - he's a good example that you can buy friends. Get banned from everywhere and laughed off by experts, then put a lot of effort and spend a lot of money to create your own universe - and you will have some followers. _Expertise_ has nothing to do with this equation. Or maybe it has; it's not technical expertise but expertise in social manipulation (or more nicely said, so called social skills).



> Well then who do you suggest we listen to


How about not listening to _anyone_ particularly, but to listen what they have (or don't have) to say, and think for yourself?

... of course, not everyone is technically competent enough to evaluate what others have to say. These people easily buy the ideas of other non-technical people (like Jack R.). Together they form a farm of non-technical people who do not have a freaking clue what they are talking about but think they do. Still, these people may hit the nail every now and then and regardless of my bad words here, what I do appreciate is the amount of data Jack and his followers produce and the fact that they [mostly] publish it openly so you can evaluate the data and just skip the [blatantly wrong] conclusions.

So, it's a good think that Jack R. has a lot of money and time to spend as it allows data to be created. For example, I do not have a lot of time nor money.


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## jddcircuit (Mar 18, 2010)

I think it was funny.
Jack is quite a character.
My hat is off to him putting himself out there.


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## onegreenev (May 18, 2012)

Well lets see. Yes, money helps but I can assure you that Jack does know and does DO and does put himself out there and he even tells all you skeptics to do your own testing. Reason he does that is because he wants you to know that he DOES know what he is doing. His testing is being done by many others who actually have very little money compared to him and those tests DO confirm the results. If a test is done and it is repeatable it is what it is no matter how much you want it to be something else. The problem I have learned is that many want to results to confirm their thinking but it usually does not. People get pissed when the truth is laid out in the open for all to see. It really does not take a millionaire to do any of this and quite frankly most who are doing these things are not. Many do however have plenty of money and have shops and educations to pursue this Electric Car thing. I have done plenty of testing and my tests confirm what Jack and others have said all along. 

His show is just that, a show. His way. Not yours. Testing goes on daily at his place. Ive been there. 

Sorry your sore that you don't have the money he does or the desire to do what you can with what you have. 

I trust him and yes, he does make mistakes. He is at least one that will admit where many others will not. 

There is no EASY way. No EASY Button. You need to deal with the issues on the terms of what IS. If the battery needs bottom balanced (truly they do) then just bottom balance them. No big deal. If you need a device between your DC DC so it does not blow then put it there. What ever is found you need then do it. Easy, hard or what ever. Too many try to make something too easy and totally screw it up. 

I think the biggest issue for most with Jack is his solid stand on bottom balancing. Mostly that is the issue. 

Others don't like his attitude. Oh well, no skin off his back. He could care less. Don't like HIS show? Do your own. Spread the word. Spread the knowledge. Show the work and show your knowledge. If someone is not really out there how the heck are you to know if what your getting is really RIGHT or TRUE. Test and test and test and test some more. Then put out the data no matter what that data says. 

Got something new, show it, test it test it and test it again then put the information out there. If it is good then others will snag on it and utilize it in their builds. That is how we grow and get better. If your testing shows it does not work or does not work good enough then let it be know so others don't waste there time or screw something up. 

Participate with video, photos, builds and testing. That is what JACK wants and that is what I see is NEEDED. Don't you want to participate? If you think something that Jack is doing is wrong then do your testing and let other follow the same test to prove it wrong. That is what you do. 

Pete


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## onegreenev (May 18, 2012)

My hat is off to anyone who puts them selves out there. Videos tests or what ever. I can say that watching his show is not much different than wasting hours here on the DIY.


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## onegreenev (May 18, 2012)

Love the show and love reading here on DIY. When the reading is worth reading.


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## Ampster (Oct 6, 2012)

Siwastaja said:


> It never stops amazing me how some people take this guy seriously.
> 
> Another thing I'm surprised at is how anyone has time to watch his 2-hour videos that mostly contain chit-chatting with a few minutes of actual data in the middle, hard to find without fully watching the show.


I watch in on youtube, then I can fast forward through the boring parts.


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## Siwastaja (Aug 1, 2012)

^^ Well, you may think that way, but in my perspective, Jack is repeating simple tests and doing the same mistakes we already perfectly know of. He is killing his cells over and over again on overdischarge, while we knew that would happen from the beginning. It's not a new data point. And he can only supply one solution (bottom balancing) to the problem, which we knew from the beginning -- and we also know other solutions to the problem that work better when done right and solve inherent problems of bottom balancing. If this option is mentioned, a flame war starts; in Jack's universe, there always is just one solution directly from the God. And his solution doesn't have flaws.

(By the way, if you are thinking what the inherent flaw of Jack-style bottom balancing is, it is the possibility of over_charge_ _or_ the need to sacrifice the pack energy. A proper BMS solves this and maximizes the energy. The flaw of the BMS is the price, and the possibility of an overengineered or poorly installed product.)

Jack, however, has _other_ interesting datapoints such as how different cells perform. This can only be obtained by testing as the manufacturers tend to supply too little data. And this kind of testing takes the most time and money.

Destroying the cells in the ways everyone know will destroy them, and then claiming something hilarious as a conclusion is just useless waste of money and time. But it's his money and time, agreed.

I once believed that his war on BMS could be based on reality, but it doesn't look much so. I've been trying to find reports of failing BMS's in _reality_ and they seem to work reliably, even the horrible, overengineered kludges that I'd never put in my car.

But, I have a saying here:

"You can always fail."


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## onegreenev (May 18, 2012)

Actually you can't maximize past the lowest capacity cell. Good luck doing that. It is well know from testing and charging and discharging that those extra little amps into the full cell will net you nearly nothing but will do more harm to the cell than good. So the object is to utilize the best of the charge/discharge cure and leave the top and bottom off and maximize the life yet know you have excellent power and range. It is far easier to add a couple extra cells and forgo the BMS garbage and yield an excellent range if that is what your after. 

Why make something so simple so complex. 

Pete 

Can I visit your current build online? I like to see how yours is coming along.


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## onegreenev (May 18, 2012)

Yup, you can always fail. Learn from failure. You can always learn and succeed too.


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## onegreenev (May 18, 2012)

Granted Jack is a bit of an edgy cheeky fellow but you know, he does a lot of good and investigates and at least promotes. If we did not have someone to follow, the movement would be in a bit of disarray. It needs some direction. No one else is giving that. He does not want to do it all and wants us to join in and participate and not have hundreds of waring factions thinking that their way is the only and best way.


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## Siwastaja (Aug 1, 2012)

onegreenev said:


> Actually you can't maximize past the lowest capacity cell.


You have misunderstood the point completely; you maximize _energy_ by maximizing _voltage_, which happens when the cells are at highest possible SoC, which means that every cell start from the same SoC (100%) when the discharging starts. I think Elithion has a video on Youtube which explains this clearly. It is true that higher SoC makes the deterioration process more quick, but at least one high-SoC cell also exists in a bottom balanced system. In _reality_, the difference in energy is small, however.

So, nobody is putting any extra amp hours into a full cell. BMS is exactly there to _prevent_ it. Top balancing allows to have maximal energy _without_ overcharging.

In _addition_, you can (and should) add some leeway on the top to slow down the deterioration. This is especially significant with LiCo chemistry.




> Can I visit your current build online? I like to see how yours is coming along.


Not much online as of yet, and we have two conversions going on at the same time, but you can take a look at:
http://www.youtube.com/watch?v=daYXNsyvWhg
http://www.youtube.com/watch?v=KaCTVe_FCYg

(DIY rewound industrial AC motor with DIY controller made from scratch, with DIY algorithm. Lead acid currently, but RC LIPO (with a BMS) will be installed soon. A digital BMS has been prototyped a little. The cell module component count is about ten components (including all resistors and capacitors) and the total component cost is about $2 per cell. Talk about complexity...)


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## EVfun (Mar 14, 2010)

onegreenev said:


> Granted Jack is a bit of an edgy cheeky fellow but you know, he does a lot of good and investigates and at least promotes. If we did not have someone to follow, the movement would be in a bit of disarray. It needs some direction. No one else is giving that. He does not want to do it all and wants us to join in and participate and not have hundreds of waring factions thinking that their way is the only and best way.


 "Thinking that their way is the only and best way" sounds like Jack!


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## onegreenev (May 18, 2012)

Actually I did not misunderstand at all. You CAN bottom balance at a static charge. Once. Then charge from there to 3.5 volts per cell average per pack. Guaranteed none will ever overcharge. If you do happen to have one or two that do happen to overcharge then those are cells that need to be removed and replaced. You do need a well balanced pack but its not hard to get with new cells. Once bottom balanced you charge to a specified voltage and terminate. Or you could even say I can put in lets say 100 ah into a 120 ah pack. Staying off the bottom results in using the portion of the charge that is above the steep curve and at the top your off the steep curve so you utilize the maximum best section of the charge. Top balancing puts all that at the top and not at the bottom but does not really give you much better power than if you bottom balanced. That TOP portion you talk about that is a bit higher energy burns off real fast and is actually of no use. If I bottom balance and stop at 3.5 volts per cell and don't even bother with the CV portion I will still not loose much. Some how you think that that tiny bit is really a big deal. Its not and you don't need a BMS to maintain that level of power and you still can't go further than the lowest capacity. Top balancing will require you to have some system in place to keep you from over discharging your pack below the lowest capacity cell to keep it from being destroyed in a heart beat. 

So to avoid the complexity of the BMS just bottom balance ONCE. Get an extra cell or two into your pack and go with it. You might try it and see for yourself. 

But since your going to use cells that DO require balancing because the cells will discharge on their own then a BMS is needed but you still the issues of the spaghetti wiring and connection issues that Will crop up. Be careful. Not all BMS systems are as fool proof as you might think. Not even OEM BMS systems. Ask me how I know. 

I am full in the camp of bottom balancing ONCE and then staying off the top. No need for a BMS to do that. I stay off the bottom and top and there is no BMS system involved. Well not a BMS system that folks would call a BMS system. I do have a smart charger and controller. I do bottom balance, ONCE. Once is all that is needed. And we are talking about the most common cells being used today? LiFePO4 cells and I'd pretty much wager that you could do this with other cells too. Bet other lithium cells don't really self discharge unless you have a system that causes a discharge. They are nothing like the old lead acid cells. 

Its your money. Go for it. 

I won't hate you for using a BMS. I'll go have a look at what you have going. Love seeing what others are doing.


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## onegreenev (May 18, 2012)

EVfun said:


> "Thinking that their way is the only and best way" sounds like Jack!


It is a GOOD way. I have never heard of a bad pack his way. EVER.


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## Siwastaja (Aug 1, 2012)

Haha, it's quite typical for human mind to try to find nice sides from someone like Jack, and try to explain the bad behavior as something which is actually good.

Like, you know, when the rape victims think their rapists actually were nice and just lonely and didn't mean any harm, what was this phenomenon called again?

Or, liking the oil, smell and noise from internal combustion engines and disliking the alternatives.

Don't take this post too seriously.


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## onegreenev (May 18, 2012)

I won't. But I do actually test things myself so I know I am not blindly following a leader. He has even said to do so. What voltage is that little car of yours? Self wound motor? Cool.


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## onegreenev (May 18, 2012)

Stockholm syndrome


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## Siwastaja (Aug 1, 2012)

onegreenev said:


> I won't. But I do actually test things myself so I know I am not blindly following a leader. He has even said to do so. What voltage is that little car of yours? Self wound motor? Cool.


96 volts (8 x 12V) for now, giving top speed of about 50 km/h on flat, but we designed the motor windings for 320VDC (designed to give nominal torque at 4500 rpm at that voltage). The "LIPO" pack will be 333 volts and hopefully gives proper highway speeds. The range will be only about 10 km though with the 1.5 kWh pack. The larger conversion (a small van) will have a proper LiFePO4 pack of about 12.8 kWh. We have a motor under the rewinding process for that car now.


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## Duncan (Dec 8, 2008)

EVfun said:


> "Thinking that their way is the only and best way" sounds like Jack!


Sounds like Swatstica or whatever his name is as well


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