Jack Rickard No BMS

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offgridQLD
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Jack Rickard No BMS

Post by offgridQLD » Tue, 10 Nov 2015, 01:57

Looks like Jack Rickard is having great success with his bottom balancing and no BMS Image

Poor bugger.




https://www.youtube.com/watch?v=O-PaSSTA2YE

Kurt

[ Edit Coulomb: it turns out that bottom balancing had nothing to do with this, see 3 posts down. ]
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Post by Adverse Effects » Tue, 10 Nov 2015, 06:51

if you listen he says someone / one of his workers drained a battery to much and when he went to charge it it blew
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Post by offgridQLD » Tue, 10 Nov 2015, 12:41

I just don't get it. Why he can't just run at least a simple cell level LVD. Instead of just relying on bottom ballancing. It had to happen one day.

I wonder what cells it was A block of his Nissan leaf cells, calbs or perhaps somthing different.


I have never trusted any cell again that has been taken down to low.


I guess on the positive side somthing might be learned from it.

Kurt

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Post by offgridQLD » Tue, 10 Nov 2015, 13:53

Turns out after reading the blog it was one of his Better Place battery packs from the Renaults. (Nissan leaf cells) that they had on a test bench. So wasn't a bottom balanced pack. Though over discharged and then attempted to fully charge, some what untended by the sound of it.

The fireball to the roof sounds impressive.

description of event in blog
http://evtv.me/2015/11/a-dark-and-sunny-sunday/

Kurt
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Post by 7circle » Tue, 10 Nov 2015, 19:38

What frustrates me and I think others is these guys have all these resources available to themn and this is the best they come up with ... ???

They tinker around and don't consider the reality and physics of the hardware and system design.

OI think a car powered by a few cows on a tread mill might be a better option ...

Sorry guys not having a good day.

7C

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Post by galderdi » Tue, 10 Nov 2015, 22:41

If those are A2 cows count me in. So long as its rear engined (wouldn't want the cows in my face)
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Post by Adverse Effects » Wed, 11 Nov 2015, 00:27

ahh i know the pack he is talking about it was unopened and strate out of the shipping crate

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Post by Vectrix150V » Wed, 11 Nov 2015, 17:32

That blinding belief in bottom balancing, and a mistrust (hatred?) of all things BMS led to this.

Funny that he actually he had no success in bottom balancing leaf cells, and admitted they probably need a BMS.

No, really Jack?

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Post by offgridQLD » Wed, 11 Nov 2015, 18:29

Hang on as mentioned later on. This was a stock better place pack that was untouched.

I'm not sure if the BMS was a external part of this better place pack (as in they were just using the pack raw without the BMS, cell level monitoring, balancing.

In fact I'm not sure at all how they were determining SOC and what criteria they were using to charge this pack.

Though considering his staff where able to drain the pack completely. I guess we can assume he had no LVD at cell or pack level.

I don't think any bottom balancing nonsense was performed on the pack as it wasn't opened.

The interesting part for me anyhow is the reaction that unfolded from the event. A huge flame ball to the cieling of a industrial work shop sounds dramatic.

Given a cell level BMS failure isn't totally out of the question even on any pack that has a functioning BMS the outcome is something I am interested in know more about.

Personally no lithium batterys (or any chemestry) other than what is installed in big name OEM consumer goods. So that I have a company to fall back on if there is a issue. End up in (as in stored in) my house. Even small lithium cells from toys (from lesser known brands) all go in a steel box in the shed for storage.

Even lifepo4 cells. Same for the house lithium cells. Fire rated room away from the house. It Might sound over the top but fires are serious things and if it's something I have build myself and I have no one to turn to if for some odd reason something bad happens I want to eliminate or at least minimize that risk.

Probably something we all should think about when playing around with batterys. Minimize the risk for the .000001% chance something unexpected happens.

Kurt
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Post by Johny » Wed, 11 Nov 2015, 18:53

offgridQLD wrote:Probably something we all should think about when playing around with batterys. Minimize the risk for the .000001% chance something unexpected happens.

Kurt
Yes, I don't like Jack or his ideas much but..."There but for the grace of God go I.".

I'm afraid I do expect better of someone who has set themselves up as such an expert though.

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Post by T1 Terry » Wed, 11 Nov 2015, 21:17

A lesson for all who thought any lithium battery other than LiFeP04 was safe these days. Some were suggesting that it was only the older tech LiPo etc that went up in flames and the manufacture process is far more refined these days..... Jack has just proven that concept wrong.
Now, that electric vehicle with the repurposed proprietary battery pack is maybe not such a great idea if you plan to recharge it under the house or similar. If the factory BMS drops its bundle and goes up in flames you have some recourse, they aren't going to back someone who is tinkering with their battery pack though.
For all their faults, I'll be staying with LiFeP04 for the near future.... and I was seriously thinking of moving to one of the other chemistry cells up until now, so thankyou Jack
Keep in mind, Jack is starting to loose his marbles, he will be the first to tell you that, Jack has lost a lot of the skilled staff from his workshop and has apparently replaced them with not so skilled staff. Jack has a history of putting LiFeP04 cells on charge and forgetting them, they will just die, the other chemistry is not so forgiving. His blog suggests he had forgotten he put the pack on charge as he was wandering around looking for the source of the noise, with all the marbles rolling the same way the first thing that would come to mind is that battery pack you put on charge

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Post by offgridQLD » Wed, 11 Nov 2015, 22:34

I think some of his methods make (Him) the BMS so he increase the risk of something going wrong due to human error no matter what the chemistry.He just got to relaxed about it all, I'm sure he will respect the operational criteria of the cells a little more now.

I treat all batterys as you would any other stored energy , can of fuel, BBQ bottle of gas. Like it has the potential to burn given the correct situation.

Plenty of story's of people pulling into there garage (attached to there house) and there gas car has caught fire. Dry grass on the the exhaust or some rubber part gets to hot.

One of our rental property's had a fire where the tenant packed a jet ski away on a trailer in the garage under the house and some how it caught fire on it's own. Lucky they were able to push it out of the house befor it did any damage.

Put the stuff out in the garden shed even a garden shed. Or build a fire proof box for it. Treat it like any other fuel.

Kurt


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Post by offgridQLD » Wed, 11 Nov 2015, 22:58

He has a video up now about what happen with pics of whats remaining.

Starts about 40min into his video.

[ Edit Coulomb: I make it about 21:30 into the video. ]

Kurt
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Jack Rickard No BMS

Post by evric » Wed, 11 Nov 2015, 23:01

offgridQLD wrote: He has a video up now about what happen with pics of whats remaining.

Starts about 40min into his video.

Kurt


Hey Kurt, please you give us the URL of the video.

Thanks
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Post by offgridQLD » Wed, 11 Nov 2015, 23:17

Video front center dated Monday 9th November. Plays on the webpage.
Type this in your browser..couldn't get a working link

http://evtv.me/

Damage wasn't to bad. Though he explains how it spewed it's guts out 10 feet in front of it then shot a fire ball to the roof. That mushroomed out to the walls sounds impressive.

As for the lifepo4 vs leaf cells and the like. I think it's just a bit like diesel and petrol. Sure petrol is a lot more reactive if you play with a match near it. Though everyone isn't shying away from it just because diesel is safer. You just work with it and respect it's property's.

They over discharged a 360v pack down to under 100v with no LVD. Then tried charging it several times to 100%. Most people would no that's not smart. Just like leaving a open can of petrol in a small hot room then investigating it with a zipo lighter.

Kurt

[ edited by Webmaster to make active link (one benefit of the edit function Image ) ]
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Post by jonescg » Thu, 12 Nov 2015, 02:23

Yeah, I have about 21 kWh of LiPo (lithium cobalt) battery packs and spare cells in my shed and it's never been a problem. They have never been drained lower than 2.8 V and never charged more than 4.2 V. Keep a cell in its happy range and it will serve you well. Only cell fires I've had are ones I intentionally started myself.

As for battery/fuel comparisons, it's a bit like hydropower too. If the dam is at record lows, or so full its about to burst its banks, we're all in trouble! Fortunately the stored energy is so vast you have a good buffer.
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Post by weber » Wed, 09 Dec 2015, 06:03

In the immediate aftermath of Jack Rickard's recent battery fire, I thought "Now's not the time to say I told you so". But now, some weeks down the track, I just went looking for more detail from Jack on what exactly the battery discharging and charging setup was, what exactly went wrong, and what lessons he learned about how to prevent it happening again. I knew not to expect any admission that he personally (rather than some unnamed "assclowns") was to blame.

It appears the sum total of information is pretty much still only that contained in this quote:
Jack Rickard wrote:POP. BANG.

What was that? Sounded like somebody banging on one of the closed garage doors. BANG POP POP. What the hell?

I went into the next room to see who was banging on the door, but as I reached to open the door, the POP POP BANG sounded again but BEHIND me. I walked over to the Better Place battery pack from the Renault Influenza that we use on the OEM components test bench. BANG POP POP. These are actually pretty loud. What the……?????

This pack was right out of the cargo container and we never even attempted a bottom balance. We were only going to use it for testing chargers and DC-DC converters and the UQM test bench. But as the result of one of our assclowns playing around with the bench while I wasn’t in the shop, it had drained down very slowly overnight to a very low level.

It seemed to charge back up ok. But never quite got to full charge. So I had hooked it up earlier in the afternoon to bring it up some more.

I quickly shut off the charger and cut off the contactors. But it continued to BANG and POP irregularly. I can’t leave to go to bridge with it like this I’m thinking. As there had been several of these “no show” moments in the past few weeks where I threw my wife under the bus with regards to one plan or another, this was not really good. I can’t believe I’m doing this again.

Suddenly the pack begins to issue the familiar white smoke – just a bit at first, then more. The pack weighs 450 lbs, and the fork lift is at the other end of the building. I went over to the wall water spigot, glad I had a couple hundred feet of hose there to water our grass. No hose. Assclown somewhere had made command level decision to move it down to the basement in the other building apparently. There was a hose, but it was four feet long.

By this time the white smoke was coming out pretty good. I don’t know why, but I was curious what the temps were. So I grabbed an infrared gun and shot all the cells. Most were warmish in the 35-40C range but there were two sitting at 95C. Not good.

Suddenly the pack spewed a spear of sparks and flame about six feet straight out the front – right where I had been a moment before. And then it exploded into a massive fireball shooting flames up to the ceiling with such velocity that they splashed laterally from there.
His two recent blogs give no further information about the fire. They consist almost entirely of right-wing homophobic political and religious rants having no relevance whatsoever to batteries or EVs.

The only additional info in the video referred to above, is in effect: "It's all cleaned up now but this is where it happened."

One thing we can be absolutely certain of: There was no BMS even connected to that pack. Because if there was, Jack would have blamed it for the fire. And of course if there had been a BMS that was actually in operation, and in control of the battery contactor (or even just raising an audible alarm), neither the deep discharge, nor any overcharge, could have happened.

I guess I shouldn't be surprised that there has been no further discussion of the causes of the fire, since that would challenge the central dogma of the Rickardist Church of Dangerous Misinformation (TM), that BMS are unnecessary, and indeed harmful.

While it's sad to hear that that Jack is "losing his marbles", I hope that, if true, it is becoming apparent even to the faithful. And one has to wonder whether perhaps he might already have been a few tom-bowlers short of a bag, back when he first converted the sensible observation that a badly designed BMS is worse than no BMS, into the fallacy that no one ever needs a BMS (by which I mean, at a minimum, cell-level under and over voltage monitoring).

The Renault Fluence battery is a 400 V battery containing a series string of 96 cells (or rather pairs-of-cells-in-parallel). I'm pretty sure their chemistry is NMC, also called NCM.

Here are two hypotheses based on the limited information I have.

1. It may have been due to failing to stop charging when the first cell reached 4.2 V. This wouldn't have been a problem if they had recently been top balanced. The deep discharge plays no part in this hypothesis.

The pack may have been sitting uncharged for many months or years before being shipped to EVTV, and particularly if it was a used pack, it may have had different rates of self-discharge (low though it is) for different cells, leading to an imbalance in states of charge between cells. Jack says they never bottom balanced it, which, coming from Jack, means they never balanced it in any way.

A clue is: "It seemed to charge back up ok. But never quite got to full charge. So I had hooked it up earlier in the afternoon to bring it up some more."

Since charge termination would only have been based on overall battery voltage, and current, it may well have been that many cells had leveled off just beyond the 4.3 V level, where the damaging reactions take place, namely breaking down the electrolyte, generating gas pressure, plating metallic lithium onto the anode, and generating heat, while many other cells were still well below 4.0 V and thereby keeping the total voltage low.

And maybe, eventually, one of those overcharged cells formed an internal short due to a lithium dendrite.

2. It may have been due to recharging after that deep discharge.

When discharged below about 2 volts, copper from the anode current collector dissolves in the electrolyte. On recharging, the copper plates out and forms copper dendrites which eventually cause an internal short.

But then I'm probably just trying to "type myself smart". Image

By the way, did you know Jack "received a special dispensation from the Pope at age eight, [so he] can’t actually be physically harmed". Watch out if you're standing next to him though. Search for "Pope" on this page. http://evtv.me/2015/11/a-dark-and-sunny-sunday/

A special Papal decree also gives him "the unique permission to make sh*t up and it be pretty close to how it works".
See https://www.youtube.com/watch?v=Ce-KFHjDsYc 3:47 to 4:53. Almost a 2 hour talk with the same powerpoint slide. Jay Whitacre he aint.
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Post by T1 Terry » Wed, 09 Dec 2015, 10:24

Try to keep in mind the Jack formed his philosophy of no BMS and bottom balancing using LiFeP04 cells, they don't burst into flame, just "let the smoke out" I think in the first video after the fire he says that these chemistry batteries probably can't be used without a BMS.
Probably the best non BMS protection would be the method used by Jehu Garcia in his used computer battery cell packs by adding solder links between the cells and the bus bar, a cell overheat results in the solder link fusing and dropping that cell from the pack.
Sure these other chemistry lithium batteries give more punch per lb, but they also add a major fire risk. I'm still not convinced you can use the full capacity of these cells without taking serious risks, at 80% capacity are they that much lighter than the equivalent capacity LiFeP04 battery?

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Post by T1 Terry » Wed, 09 Dec 2015, 10:40

While reading a Wiki article Renault Fluence on the battery pack they say "Renault will have to buy batteries from a joint venture between Nissan Motor and NEC, and from LG Chem of South Korea.[8]" Does this mean the Leaf battery pack could go the same way? Let's face it, the vehicle BMS is not much more than staying well away from the top and bottom areas as far as battery capacity and temp monitoring. Tesla have active cell temp control but does the Nissan Leaf?

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Post by offgridQLD » Wed, 09 Dec 2015, 14:04

Good analysis Weber.

I agree Jacks personality - attitude is not one I warm to. I only find myself sifting through his videos as I find anything EV or battery related interesting. His non EV related rants and drawn out presentations with questionable facts. Receive the fast forward treatment on you tube.

Though some times you can learn something from the guys mistakes and at times he has guests on his show with something interesting to say or show.

The funny thing is if you watch his latest show you will find out that he has had battery issues with almost every EV he has build.In his latest show you see his yellow VW thing had the battery bank completely drained down (again he blamed it on another person) A few of the cells where damaged beyond recovery. His Cadillac Escalade 4wd was also drained all the way down and he lost several 400ah cells beyond recovery from that.

So his EV projects have the ability to drain the battery completely if something simple is overlooked. Like the key in the ignition or interior light on and he keeps killing his battery banks because of this lack of LVD. I think he knows he needs one but to save face he doesn't want to admit it. It's just a shame he has the money reserves to keep replacing cells all the time.

Yes Weber, he is loosing his marbles. Whats that saying again....

"The definition of insanity is doing the same thing over and over again and expecting different results"

Kurt





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Post by T1 Terry » Wed, 09 Dec 2015, 14:34

Besides the devoted, I think most watch Jack's offerings to either cure insomnia or what not to do if you don't have the $$ to keep replacing cells. Once he moved from scratch builds to repurposing junked parts from other EV's I lost interest in watching. What happened to the guy who was the co host in the early days? I think he kept Jack a little more on track but without him there I just can't stay awake long enough to listen to prattle I'm afraid.

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Post by weber » Wed, 09 Dec 2015, 18:37

T1 Terry wrote: Try to keep in mind the Jack formed his philosophy of no BMS and bottom balancing using LiFeP04 cells, they don't burst into flame, just "let the smoke out"
Yes. But we don't want to "let the smoke out" either, since it means the cell is destroyed. And that "smoke" is possibly blinding and lung-corroding, and definitely highly flammable and with a very low flashpoint, and so it is quite likely to turn to flame. And yes, a poorly designed BMS could well be the ignition source. But a well designed BMS will prevent it from happening in the first place.
I think in the first video after the fire he says that these chemistry batteries probably can't be used without a BMS.
That would be quite an admission. So I went looking. It wasn't in the video, but buried in the comments after it. Thanks for correcting me on that, Terry.

So Jack Rickard, who would have succeeded in burning down his building, and god knows what else, if he had already left for his bridge game before the first cell popped, makes the understatement of the year. In http://evtv.me/2015/11/a-dark-and-sunny-sunday/
Jack Rickard wrote:I guess I think a BMS is probably in order with these.
Ya think?

And this is immediately followed by
I’ve had little luck bottom balancing them.
Which seems to imply, "If it was possible to bottom balance them, no one would need a BMS, even with this chemistry", which is a complete non-sequitur.

At the end of his latest papal encyclical, Jack exhorts us to get down on our knees and pray to God, to bless America and solve our problems. And then (this part I have no objection to) go out and perform some random act of kindness.

However Jack himself could prevent untold suffering by simply admitting he was wrong and telling his followers to use a good BMS whenever they have more than about 4 cells in series, of any Lithium chemistry. At the very least a BMS that provides low voltage and high voltage cutout, based on monitoring every cell individually. He could even do some great testing to figure out which BMSs are the least likely to cause imbalance and the least likely to be an ignition source in the event of catastrophic failure, and which ones can compensate for sag under load so as not to cause false alarms, etc.
T1 Terry wrote:Does this mean the Leaf battery pack could go the same way? Let's face it, the vehicle BMS is not much more than staying well away from the top and bottom areas as far as battery capacity and temp monitoring. Tesla have active cell temp control but does the Nissan Leaf?
Yes a Nissan Leaf pack would go in exactly the same way if used without a BMS and abused in the same way. Why do you say "not much more than" when that's all you need in a BMS, to prevent catastrophe. There is no active temperature control of the battery in a Leaf.

Here's an example of where "mak[ing] sh*t up and it be pretty close to how it works" is nowhere near good enough.

From http://evtv.me/2012/08/a-bit-of-this-a-dash-of-that/
Jack Rickard wrote:What happens when we over discharge our cells? Well, we are moving lithium ions from their cozy location in the graphite on the anode, through the electrolyte and into the cathode. If we continue past a certain level, a couple of things happen AGAIN. First, we again go into oxidation and produce CO2 and our batteries swell. Second, we start to emerge copper from the copper foil the anode rests on through the carbon in a streamer we will refer to as a shunt. It penetrates the separator and connects to the next “cell” that is, between two foils inside the cell. ANd it shorts them out. The more of them that are shorted, the less cell you have active. And they cause heat. The most common cause of death is over discharge. You cannot make the shunts go away. A little swelling is telling. But the shunts are death.
So where did he go wrong? He thinks the copper shunts (dendrites) form during the over-discharge. They do not. They form when you recharge after an over-discharge. So presumably he thought that since the cells hadn't got hot immediately after the deep discharge, there must be no copper shunts, so it must be perfectly safe to recharge them. Wrong!
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Post by T1 Terry » Wed, 09 Dec 2015, 21:38

The not much more than refers to not monitoring individual cell voltages to determine end of capacity or end of charge, nor do they monitor or control cell temp as you have pointed out.
As far as the recharge after deep discharge, gently gently does it to avoid the voltage and temp spikes seems to be the trick after recovering a few LiFe cells that were under 1v, no idea about the leaf chemistry cells though.

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Post by weber » Wed, 09 Dec 2015, 22:06

T1 Terry wrote: The not much more than refers to not monitoring individual cell voltages to determine end of capacity or end of charge, nor do they monitor or control cell temp as you have pointed out.
Thanks for clarifying. We have misunderstood each other.

The Leaf most certainly does monitor voltage of individual cells (or parallel pairs to be precise). Coulomb and I have partly traced the circuit of the BMS. And I'm pretty sure it will reduce charge or driving current as required to keep any single cell within the safe operating region, irrespective of what it thinks the overall SoC of the battery is (based on coulomb counting).

And it certainly monitors cell temperatures. Not of every cell, but of a significant fraction of them (maybe every third "sardine can"), since it can rely on heat conduction between them.

It can also perform cell balancing, with a maximum 10 mA bypass, at any state of charge.
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