So a long show this week. Some say long and boring. I would be wounded to think this is so. Is not the entire world hanging breath abated for the next few minutes of every episode? That is of course my fantasy. Were reality to intrude I might be crushed.
This week, we flew into a flurry of work. Some battery stuff, reassembled the pieces of Netgain Warp 9 we had been using as a visual aid. It turns.
But of course, the lion’s share of this weeks work revolved around finally installing the Siamese 11 inch motors in the Escalade and connected to the 6L80E transmission and torque converter.
In the end, I’m just terribly pleased with how this all came out.
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The two motors are of course painted gloss black and have shiny aluminum end bells – perfectly color coordinated with the vehicle. But even better, the overall LENGTH worked out so well it looks like it was all done on purpose. We have about 1.5 inches between the reluctor ring and the front crossmember of the vehicle.
By shaving the stock engine mounts about a 1/4 inch each, the motor and mounting plates drop right in place. And our adapter plate mounts perfectly to the transmission.
We DID have to add a spacer to the mounting plate to pull the torque converter out of the recess for it enough to not bind. And actually when we did finally put it all in place, it DID bind. We loosened the bolts around the transmission, jacked the motor UP and then jacked it back down, and heard a distinct “thunk”. Retightened the transmission bolts and the shaft turned like a dream.
We then went to our tiny access hole to insert our torque converter bolts. We could see both the flex plate and torque converter easily and line up the holes in seconds. But we could NOT get a bolt to start.
Brain wheeled out his air driven burr grinder and “expanded” the access hole a bit. And finally we were able to bolt it together.
This week we’ll add tranny fluid to the thing, and idle it with a 12v battery. We’ll let it sit for awhile and then add more tranny fluid. It takes a bit to get it pumped into the new empty torque converter.
We had ordered a 6L80E torque converter from Professional Torque Converters with a lowered 1400 rpm stall speed. This should more closely match the torque curve of our electric motors, and make our system more efficient at lower speeds. It will also reduce the heat (and thus losses) generated by the drive train.
The concept of using a torque converter at all is largely to provide a hydraulic buffer between the
electric motor and the AWD drive train. Torque “lockup” apparently occurs in 2nd gear above 22 mph. By having the “stall” speed – at which basically the two turbines are turning at the same speed anyway, somewhat below that, we hope to get a smoother transition to lockup whether we are accelerating briskly, or slowly.
The replacement torque converter arrived Friday morning – just in time. We actually worked most of the day and shot the intro sequences quite late – finishing at 6:30PM. Yes, I was late for the ballet.
In the end, the motor is very securely mounted in the truck. Looks like it was born to be there. We’ve got a good line along the transmission and drive shaft. The rubber mounts should minimize vibration. It’s almost the perfect length. And of course it looks gorgeous in the vehicle.
With the motor mounted and the battery box in, balanced, and charged, we are actually moving into the area I like the most. Wiring up the controllers and the instrumentation.
We also have to do the environmentals – largely our water heater – along with a cooling system for the controllers. So we will have two separate glycol systems – a bit complicated with two separate pumps of course.
So while much work remains, our past projects would indicate that we are actually 2/3 done with this project. We should be rolling rather shortly.
No matter how many of these we do, I never quite get over it. That this will be the largest passenger car I’ve ever seen done is no help there. But truly, I always loved this vehicle anyway. For me, at 280 lbs with knees and hips that aren’t as young and pretty as they once were, it is very comfortable to enter and exit. Onboard, I sit up quite high with superb visibility in all directions. The seats are very wide and plush with air conditioning vented up through tiny holes in the leather and resistive electric heat available as well.
The GPS and entertainment are actually a bit sorry. The GM GPS is actually good for a laugh, we used to enter a destination and howl over the route it provided. There is no USB or iPhone connection. So we may do some work on the console and replace the existing unit with a more advanced one – perhaps with a carputer interface and iPhone connections. But this will all happen AFTER we have it fully functional with electric drive.
In the end, we should have reasonably comfortable seating for four adults, five in a pinch. I think we’ll have the usual 80-100 mile range in town. But there is potential for some blue sky on the highway.
We noted on the Ford Edge a staggering 4.5 Amp hours at 250 volts or 1125 wH per mile. The transmission has never been right on this car and so with 200Ah at 250 volts we hardly had a 45 mile range.
Incredibly, at 70 mph on the freeway this drops to 2.0 Ah or 500wH per mile – less than half. The vehicle weighs 5000 lbs. This is the REVERSE of our experience with the Speedsters and Spyder and Cobra. How can this be?
A couple of things come to mind. Mass is intractable. It just is. And it takes a definitive amount of energy to accelerate a mass – more mass, more energy. The edge has 2.5 x the mass of the Speedsters. But it is UNLIKELY that it has 2.5 x the frontal area.
And so while air resistance is a square function, the energy use profile does indeed invert – not because the vehicle is particularly good at rolling down the freeway at 70 mph – 500wH and 5000 lbs is almost exactly the 10:1 rule of thumb we use to estimate energy usage.
No, the issue is how very BAD it is at accelerating 5000 lbs from dead still to 35 mph.
I’m hopeful that the six speed 6L80E with a kind of extreme overdrive 6th gear coupled with our two 11 inch motors will give us an even better profile at highway speeds. And so I would look for something like 70-80 miles per charge in town, but potentially 120 or even 130 mile range on the freeway. This puts us in range of St. Louis – 110 miles away, with this truck.
We’ll see.
Jack Rickard
Greetings from the old world
You are stealing my oven trick, and point it out like Brians idea….very funny, boys…)
So everything that missed on the Mayflower can be catched up on YouTube in these days.
Ahoy
Mathieu Rech
P.S. My wife said that you probably wouldn’t talk to me anymore, but I think you’re smart enough to see the humor in this post also.
Ohne,
Every little boy knows things shrink when it gets cold.
I’ve done loads with the oven and liquid nitrogen thing. One place I worked considered the “gases” that came off Liquid nitrogen like a poison. “So where should I do this job then?”. “Do it out of harms way, under those stairs”.
I tried telling them “it’s not poisonous but an asphyxiant”. They thought I was taking the Mick because it did not smell like bum gas.
And they say the UK is a good place for an education.
====================================
Hey what a good show! I bet Brian would of been happier to fit the clutch and gearbox on the bench then lowered the car over it, then bolted it in.
====================================
The guy with the 125(?) mile brush life.. Was he running the motor backwards? That will do it through excessive arcing because the timing will be out.
I’lll talk to you all you like Mathieu. And yes, I stole your idea outright. That assumes of course, that you INVENTED heating a bearing to a shaft?????
Jack Rickard
Got me. No, I only have the patent on gravity…
Jack, you know that you are doing a great job. As you said: “it’s your show, and you talk about what you want to take about…”
My only point would be: Don’t get too patriotic. WE are all over this planet.
cheers
Mathieu
Gravity? Great. Now if I drop a washer on the floor, I not only have to buy a new one since I can’t REACH the floor, but I suppose I’m going to have to pay you a royalty on the event too?
Patriotic? More like disgusted. Our government has devolved to a race/gender riot under the influence of bathtub gin…
Jack
The oven trick works, but playing with Dry Ice is a lot more fun and does the same thing without having to worry about cooking the lube out of the bearings….
Hi Jack,
When bottom balancing, how close do you like to be in voltage: 0.1 Volts? 0.01?
It’s a question with no answer. On 180Ah cells, or 4 Ah cells?
I LIKE +/- 0.05. But often it is like herding cats with a five iron in a lightning storm. They move over time as you walk away from them. THis is not “drift” but “recovery” and can take up to 24 hours to settle. I don’t have 24 hours. So hit it with an exactly similar load or charge from cell to cell, hit a number, and move on.
Jack Rickard
Many thanks Jack – yes I should have said: 10 A-h nominal Headway 38120S. I’ve sent you an email with links to some of the data.
I suppose you could get them close then finish them off by connecting them in parallel for a couple of days?
Gee, I can’t imagine why there’d be a shorted cell in that A123 pack, having two “Battery Murdering Systems” on board.
While replacing the bad cells may be out of the question, can you scavenge the good cells out of the brick (and have enough tab to work with)?
Great show Jack and Brian it is refreshing to see real reality TV. Oh the excitement I felt when Brian finally found his ratchet, I can’t tell you how many times I personally have felt that triumph! The real excitement of course is, the twin 11 incher’s are securely mounted in the Elescalade… congratulations guys… Jack how was the ballet?
I made the second half. Moscow Ballet – Don Quixote.
Jack Rickard
Jack,
As I have been saying all along I want you to succeed with your Escalade project, because like you I am replacing the LS2 in my C6 Corvette with an electric motor.
Last August you had your machine shop..Cape.. machine and install a reluctor ring to the front serpentine belt assembly on the front of Jim Husted built dual-11″ motor.
What I was told then by my ECM re-flasher business that the that the Crankcase position sensor and the camshaft position sensor worked in tandem, one needed to work with the other. He suggested in reflashing the ECM that they just turn them both off.
Indeed, from this last video you explained the the Engine Control Module was simplifier then we thought, and that the Throttle Body controlled the input into the ECM so that one has cruise control. That was brilliant you took advantage of the two hall effect sensors already provided in the Throttle Body.
So if I understand correctly the information that I passed on from the ECM reflashing business was correct and the reluctor ring was not needed.
Regards,
Mark Yormark
No Mark. Off by 300 yards again. But now I understand your interest.
There is no crankcase sensor of any kind.
The crankshaft has the reflector ring mounted on it inside the engine. A sensor reads this 58 pulse ring to obtain RPM and crankshaft position which is actually QUITE necessary for the ECU to function at all. IN fact, as we point out in this week’s video, it’s really the PRIMARY heartbeat needed by the ECU. And if a lll else, it is the input for your tachometer.
The camshaft position sensor really doesn’t work with the crankshaft position at all. It works with some anti-knock sensors and a camshaft actuator and the ECU apparently has the ability to modify valve timing slightly to minimize knock noted by the anti-knock sensors., As I mentioned weeks ago You can unplug this entirely and the engine starts and runs fine.
The throttle positon sensor in the throttle body provides two scaled signals to the ECU providing feedback for throttle body position. The ECU actually positions this throttle body as the result of a number of inputs, including accelerator position and engine coolant temperature and rpm from the crankshaft reflector ring.
Using the TPS signal rather than the accelerator position allows us to use the sum of this, including for example, cruise control, to run our electric motor.
It would appear that the mass air flow sensor and manifold pressure sensor are much LESS important to shift points, and more about fuel use and emissions controlled by injector pulse width from the ECU. I’m still unclear whether MAF contributes at all to shift points and Royce Wood seems to be a little conflicted their as well. Maybe.
The book implies that MAF and MAP are inputs for transmission shifting. Mr. WOod implies they are not very important if so.
We aren’t really “ref lashing” the ECU but rather using HPTuners to modify specific variables, like the rpm and mph of each shift point up and down, for feel.
This will leave a LOT of error codes and an always on engine light. If I knew how to ref lash the entire eeprom and simply ignore signals, this would be much easier. I haven’t’ heard anywhere how to do that.
My theory from the beginning was that we always had manual shifting as a backup on this transmission. I’m convinced at this point that we WILL have automatic shifting, though I am intensely curious as to what that will feel like and what we can do to make it feel better. But at the end of the day, it’s very likely I’ll simply use manual shifting. This will allow me to lift from the throttle pedal in coordination with pressing the arrow and I’m sure it will be very smooth.
Thanks for all your best wishes. I see it remains more important to you to be right than to be successful.
Jack Rickard
Absolutely correct again, Celso,
I’d of automatically assumed the cam sensor set ignition start pulse timing (Fires once every two turns)/cylinders. Fine adjustment of the timing comes from the rpm/load ignition map via reluctor ring. Simples. Remove the cam sensor and it fires twice as often, like a motorcycle does….. and??
My last car threw an engine light for a year. It did not consume more fuel, lost no performance (what there was). In fact no issues whatsoever.
I couldn’t even be bothered to calibrate the indicator light as mentioned before.
Technology is only magic to people who don’t understand it. It’s not meant as a dig at you Mark but everything has a reason and the reasons are not complex when there is no reason to be.
Jack and Andy,
It was getting late when I wrote the above comment. I apologize. I should have said,”CRANKSHAFT POSITION SENSOR”, Not crankcase position sensor. Also, I am guilty of not watching the rest of the video that explained the reluctor rings function for the Engine Control Module.
But it still begs the question. You disconnected the cam position sensor and the I.C.E. ran. What happen when the crankshaft position sensor was disconnected? Or do you know?
I want to be absolutely certain before I purchase and design/build the attachment for the reluctor ring on the front of my motor.
Jack you originally mentioned just using the throttle body/TPS for the idling function, but discounted that idea once you discovered that the engine had a idling system by pass, so you decided you were going to use the idling feature of the Soliton.
What I am curious about is if the throttle plate was opened up slightly, would it send a signal that could generate an idle speed for the motor?
If that was the case a screw adjustment could be mounted to press against the throttle plate, therefore for others with controllers that did not have an internal idle functions a means to idle their motors.
I guess we are all a little guilty of “Having the need to be right”, which is different from “Having a need to be correct in accomplishing ones goals”
Regards,
Mark Yormark
It would of course. The theory is that the procedure the ECU uses is to close the throttle plate and idle using the bypass solenoid. The “slightly open” or what I referred to in the video as “resting” is the default failure mode. If you lose accelerator position or anything else impotent, that is the position to goes to for “limp mode” and the proper idle is with the throttle position closed.
I think you do need the reflector ring for rpm. On the Mini Cooper, we just didn’t have a heartbeat from the DME without it. With it, suddenly everything woke up. I think this is the base signal that the ECU will use to detect that the engine has started.
I plan on using the normal START signal to the starter to start the Soliton1, and it will go away once the reflector sensor detects an idle speed. Or that’s my thinking.
I’m hoping this new software release will make that 7 second startup delay on the Soliton go away. As thesis a recharge sequence for the internal contractors, there is no possibility of that. But I hope.
Jack RIckard
Hmm, lateral thinking needed if that 7 secs does not go away …
I could suggest after all is working, re-link the Soliton start to the door remote with a timer to release if door stays open too long. Cabin light timer?
The “ignition” key then by-passes. Using a diode so it does not affect the doors etc.
Will need to think about it because it could be dangerous or break stuff for all I know.
Well, the penalty is you go to IGNITION, wait 7 seconds, and then go to START on the ignition key. The problem with that is that it is at variance to how people normally start their car.
I do not like having “special procedures” to explain to people who drive our cars. They should operate as closely as possible to what is expected.
Similarly, given the current and power involved here, I’m very uncomfortable depending on the contractors in the Solitons. I would like to add two BUBBA size Kilovacs with a good bit of copper plate for dissipation to the link. But you have to energize that BEFORE you try to energize the Soliton. If you do it simultaneously, the Soliton faults out.
Jack Rickard
Ahh! I got you now. It’s the pre-charge circuit for 7+ seconds, then the ignition key?
It’s all fun 🙂
Hello Jack
I´m converting a Smart car , and that thing is full os electronics and CAN bus all over, I big problem is the gearbox that is controled by can bus.
He decided to simplify , and we left the RPM sensor of the engine, the collant fluid sensor that we are going to use also for the temperature of the Curtis, also left the mass air flow sensor but I think we dont need it.
All the other stuff we left disconnected
So far so good we are able to shift to 1st but no more because we dont have the motor mouted so no RPM readings , once we have the motor in I think we are going to be just fine.
It turns out to be very simple indeed
best regards
Soldering stainless steel: Decades ago I bought an All-State Dyna-Grip Soldering Kit No. 430 which was great for soldering stainless steel. The magic was really the flux which contained Zinc Chloride and will work fine with common electrical solder.
The soldering kit is currently sold as “430 Dynagrip Kit”
Has anyone out there documented the wiring they have added to their conversion vehicle? If you have documented the wiring, what software did you use? Or was it just pencil and paper for your own reference? My conversion vehicle has no existing 12 volt wiring so I must start from scratch and wanted to be a little professional about it.
Thanks
Al Gajda
Someone posted a link to these guys last week http://www.isispower.com/index.html they have a wiring system that looks perfect for a vehicle with no 12v wiring at the moment. The video interview (with v8tv) on their site is quite informative.
Hey Jack & Brian,
I am a week behind on EVTV so I have not seen this weeks show yet so I guess I will see the spacer ring you needed for the torque converter. I wish I had a chance to read all the post before hand. Years ago I had a similar problem with the snub on the torque converter being too long or the countersink in the crankshaft not deep enough on a 350 Chevy with a Turbo 350. I carried the torque converter over to the local converter rebuild shop and they chucked it up in the lathe and cut down the snub just a bit for me. I’m not real sure how I got the miss match, though the engine and the trans were not a pair to start with so they were never together before but this solved my problem. We had looked at making a spacer and when I called the converter shop they were the ones that suggested cutting down the snub. Just something for future reference since you already have it handled.
There used to be a Corvette guy here in Florence, Al, Paul Adams, a retired Ford engineer, that we all knew because a lot of us have had Corvettes in the past and he had once told me one of the original possible uses for the cam sensor was to get exact crankshaft/camshaft positioning for future engine starting without a starter. With the 2 sensors the PCM could determine which piston was where in their strokes and it could fire the right injectors and the right spark plugs and start the engine spinning without the use of a starter. After he told a us this he also said at that time they had not been able to make it work continually. My guess was due to the lack of compression on the mixture but I really don’t know. This was back i the late ’80’s when he was at the shop one day getting me to rebuild and old 4GC Carb for him and I got to asking him about some of the sensors for the computers on cars. At that time computers were all still fairly new to cars. Just a tidbit of info that is absolutely useless but interesting to know.
David
The transmission shaft goes into the torque converter quite a ways. Some quick measurements indicated that the snubber part might not be so solid. We didn’t know what we could take off and get away with it.
In any event, we actually DID bind even with the new spacer and the proper flex plate. But a little wiggling and it must have seated because suddenly we could turn the motor freely.
Jack Rickard
It’s been close to 20 years since I installed an automatic transmission so I could be wrong but anyway when I saw Brian installing the torque converter I was like that seemed awfully easy. When I would do one if I remember correctly that you had to have it make two thud sounds not just one. the first one was usually easy but the second one you would have to wiggle it a bit more before it would seat all the way. My point is you probably didn’t need to go through the added expenses and wasted time. But at least you got it working.
Chris
P.S. On documenting the wiring.
At the moment I am trying out a software package called “SmartDraw 2012”. They give you a 7 day free trial, and then you have to pay to continue to use it. It cost $200.00 but, besides electrical it will do about 25 other engineering disciplines. ie (hydraulics, Mechanical, Networks, Project management, Floor Plans, just to name a few) I think it is a good buy even at $200.00, but wanted to check to see if any one had found cheaper (free) electrical cad software. You can link to it at: http://www.smartdraw.com/specials/electrical.asp
Al Gajda.
Jack, considering your knee’s ‘n hips. Are you considering if you can move your model S deposit to a model X?
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David dbc105, you made good points. The cam sensor is also used to set the injectors at the right point against the firing stroke too. My bad.
Turning the spigot must of occurred to some. I thought it must be a hollow tube or the 1400rpm clutch could come with a short spigot. We live ‘n learn :-S
Not really. I really like the looks of that Aston Martin Rapide. I think Tesla is on the mark when they say they are going to produce the best sedan every built of ANY drive train.
And after a few drives, I”ll probably let my wife drive that oct of the time. I’m assuming the Escalade is actually running before the Tesla delivery.
Jack Rickard
Hi Jack,
Thanks for looking in to that A123 Module.
It’s a real bummer it’s not more robust and easily adaptable to DIY conversions. In my dreams it certainly was the quick, easy answer to utilizing the 20ah A123 cells in my car.
I’ll continue with my own sysphean tab combiner & let you know if I stumble into a worthy system.
Hey Water, I’ve bought 180 cells to run at 6P. Two of these batteries would of been great for me! Jack needs to find a way to cut out the bad cells and creatively fit anew.
Any suggestions anyone?
If they were so cheap per cell, a fix will create value added. 😉
As it is, its an overweight/sized 2P pack.
Any quality suggestions would come from getting a good look at how much tab is salvageable. I would hope for at least half the tab remaining.
——————
Jack, Is the going price for that pack still 2500 with the shorted cell? at 83 cells we’re approaching the price you have for individual cells. 😉
The topic of price is all over the place guys, that’s why I avoid talking about it. Yes, it was $10 per cell, about $840. Only it cost $1640. We are doubling the price with these guys with their DHL shipping. But we’ve had some difficulties with customs and so forth even on some little stuff recently. THis company simply refuses to ship another way, and I think they kind of know what they’re doing.
They also surcharge Paypal a right smartly. So the final pricing gets to be a problem.
Yes, I would come off the $2500 a right smart. I probably need to find out how to have an “auction” like eBay on our web site. Some stuff we need to just get rid of. It would be nice to just put some things up and let everybody bid on them for a week or so.
I’ll have to think about that with Christopher Fisher.
Jack Rickard
http://www.wpauctions.com/download/
This comment has been removed by a blog administrator.
It is possible to solder to aluminum, especially thin or small sections that don’t carry away the heat to fast. If you get a pool of rosin core electrical solder going around the tip of the soldering iron and lightly scrub the aluminum with the tip, with the pool around it, in the area where you want the solder to stick it eventually will. The molten solder and flux seal the aluminum exposed by scrubbing from oxygen so that it doesn’t have a chance to oxidize, allowing the solder to stick. I’m not sure how well this would work on the A123 tabs but it might be worth a shot.
Yeah, it eventually will. That won’t carry any current. The problem is we have multiple tabs of BATTERY wicking away the heat. I had a little copper bar fashioned to solder to it. If I apply heat to the copper bar, now the bar is wicking heat, the OTHER set of tabs is wicking heat, and my little 850C Weller just can’t quite make the numbers.
Jack Rickard
Solder paste and a heat gun perhaps?
I was musing on a way to get the bad cell out of the A123 pack and replace it. I’ve come up with something, but it’s a flawed and half baked idea. I thought I’d post it in case it sparked ideas from anyone else.
Here’s a picture of the idea:
http://imageshack.us/photo/my-images/21/cellchanging.jpg/
so the idea is to..
0.1) Tie an adjustable strap around the middle of the battery to hold it together.
0.2) Put the battery on it’s side, then cut the metal bands. You might need to replace them with an adjustable strap as you cut each one so that when you come to put it back together your compressing it in the right places.
1) Cut the aluminium connector that connects the cell tabs as shown in the diagram. No doubt this would be tremendously difficult. I’m hazy on the next bit because I don’t know quite how the battery is put together (particularly how the black plastic strips at the top work), but I’m hoping there is some way to then cut the cell tab off of the bad cell.
2a) For every 2 cells there is what I’m going to call a “plate”. The many plates form the sides and bottom of the battery. Cut the plate at the bottom edges so you can fold open the bottom of the plate where the bad cell is.
2b) slide out the bad cell.
3) slide in a new cell.
4) Cut a piece of aluminium to fill in the gap. Drill and tap 4 holes into it and the connector. Screw it down so that it’s connecting where the connector was cut and scrunching down the new cell tab. It’s a very small gap so I’m not sure how possible this is.
-Nick
I like it Nick. Untile the end. The crimps are barely 3/16 of an inch high. Any hardware we would add would preclude reinstalling the top cover. No clearance at all.
Further, I’m not sure what shape we would leave the adjoining cell tabs in after we pry off the connecting material. It IS spot welded.
Jack
Yes. 🙂
…Well I did say it was half baked.
Before you responded I went away to make another drawing. Here it is:
http://imageshack.us/photo/my-images/542/changingcell2.jpg/
In this one you drill 2 holes though the tabs, then cut and grind away at the connector until you basically have a load of blocks. Then you add a few more spacing blocks and connect the whole thing with a couple of screws and nuts.
I also don’t claim that this one is easy, possible or even a good idea.
-Nick.
Nick,
I read with interest your above posts because I have considered doing the same to the 84 each A123 20ah pack
I “copy” and “paste and search” your links with no luck.
Oh well, lets all have a go. hehe.
I suggest milling out the tabs on one side so the cell can be removed. just a minimal area to retain strength. Then insert a fresh cell after cleaning the metal out in the groove.
Then you can jam/screw in a metal strip in that top groove to reconnect.
OK, well, its a fix. Sort of.
Just had a really good look on the A123 video.
Repairing is very bad, awful news.
There seems to be a double hump in the bus bars? The tallest for the tabs and a lower, wider part I reckon centres over those plastic spacers?
If only those plastic blocks under the bus bars were deep and substantial enough to take a thread. 😉
It might be interesting to do a short segment on how to properly import from China, and the rules, fees, and other “gotchas” involved in doing so.
Yes, I could do with something like that. When will you release it?
Jack
Jack:
I gotta believe that A123 has a way to rebuild a module because it is not a molded device; Perhaps they are willing to share that process.
Given they won’t and I don’t have the module to inspect, how about an aggressive approach by cutting out the bad cell at the tabs and piggyback a new cell by spot welding it to the clip holding the cells. It doesn’t make a difference if it is laser welded or spot welded as long as you affix the tab to the clip before you weld it in place. I think I read an article on the net about making a spot welder from large caps.
It’s a welded device m’Lad.
I believe ya’; however, would you ever design a battery with expensive cells you couldn’t rebuild? As a fact, from my reading off the internet even Nissan intends to repair batteries by replacing cell modules. It’s designed that way so their batteries can be swapped out and replaced with a rebuild battery pack to meet their eight year commitment.
Err, this IS a cell module…
Jack
Nissan cell modules only have 4 cells in there,an a battery as 48 modules, that is a battery that can be mantained.
http://www.youtube.com/watch?v=1iXj0zroMhs
“And therein lies a tale!” And, it’s all about a different design decision leading to expensive scrap.
How to make a pack out of A123 20 ah cells and protect the tabs from corrosion, vibrations/metal fatigue and still be able to take it apart for possible cell replacement??
I wish I had a means of illustrating this, but see if I now can communicate the following with words…
Basic concept..two half plastic shell strapped together with polyester strapping material….
http://www.youtube.com/watch?v=Ui9YzEod50c&feature=related
The tabs would be joined together with the designed aluminum clamps that Jack is now using.
A simple mold would be created that had two 90 degree bends, ( a “U” shape) that would create an adaptable length plastic part. Two of these opposing “U” shaped parts would be used on each end of the battery pack so they can be strapped together.
The size of this male mold for the A123 20 ah cells would be 162mm wide @ the base by 260 mm to accommodate the 253mm length of the cell. Basically, a “quick and dirty” male mold would be a wood box measuring 162mm x 260mm x half of the length of the biggest string of cell that you want to lash together.
Of course other configurations and box molds dimensions could be made, even for something like for Jack’s “Flatenum Series”
Once this is all strapped together a release could be sprayed on the top ,(tab side), with Poly vinyl alcohol,PVA. Once dried, Silicone resin like the pink material that Jack used in his casting process can be poured on the top of the battery bonding and sealing everything together.
Mark Yormark
Similar idea: http://www.photobucket.com/batterypics1
(design incomplete, I didn’t detail it down to the screw. Simply a layout pictoral)
Chad, good method. Very similar to mine. Looks tough to make/assemble. But I see nothing substantial to clamp up with, yet. 😉
My method:-
I used 2 off, 10mm high, 3mm thick 160 long PVC insulator per cell (drilled with 4x 1/4″ holes), solvent glue together around the tabs. “n” shape fold the tabs opposite ways. Each following cell has to have the tabs folded opposite ways for connection.
Parallel or series:-
Depends which way you drop the next cell onto the last.
Connection:-
I’ve only 4 studs and assure clamping makes the pips squeak. The ends have stiff blocks to spread the compression. One side is threaded for the studs and the connection side has nuts. Heat is a product of resistance. We need VERY clean, smooth and tight!
Thickness:-
The 2 off 3mm thick PVC per cell.
Plus a 1.4x12x45m thick Alclad** piece between connections. (Can be more than 12mm to wick heat).
Plus the double tab fold of 0.6mm.
Gives me the 8mm cell spacing.
**Alclad is a Dural skinned aluminium sandwich (aeroplane skin). It’s alloyed with copper so improves corrosion & dissimilar metal issues. A non metallic replacement could be fibre/circuit board but will need inserting where the Sun doesn’t shine, (Under each tab).
Why the 1.4mm spacer between tabs:-
The cells GRIP my 4mm Correx boxes by sliding into its alternate channels I’ve cut out. the 7.33mm cells fits in slots 8mm apart.
Servicing:-
The Alclad part is an ok test point but to “pull” a cell these must not drop in when loosening/withdrawing the studs. Suggest holes with nylon fishing line fed through. Cell swapping is painless.
Warnings & Issues:-
It is important to understand the unfolded edges of ALL pouch cells carry current!
My pack design carries stray current through the studs because I used conducting blocks on connection ends. Therefore mine “as is” must result in an odd number of cells per pack. Thick Paxolin should work for packs with an even cell count.
AndyJ..How did you find Chad’s picture?
I was sent to the following…
New Mr.Lite AA = J4 now @ Lightake.com | BudgetLightForum.com
budgetlightforum.com/node/698
AndyJ I like Jack’s method better for clamping together the cells at the top of the aluminum taps of theA123 20ah cells, my concern is when the tabs are folded over it would cause stress to the delicate pouches. So if the cells are clamped @ the top we should all take your warning that edges of ALL pouch cells carry current! Therefore all surfaces carrying current should be insulated.
How??
I suggest in the above posting pouring the whole top of the battery tab side with CASTABLE SILICONE RESIN.
I realise that now is overkill and still would make it hard to disassemble the pack.
A simpilar solution is to only “pot” with SiO2 the individual connections.
A simple mold could be made out of cardboard. I essence you end up creating a SiO2 insulative cap.
Regarding your use of individually space cell in slots you cut in the Correx.
My understanding is that these cells need some form of compression. That is why I suggested the polyester banding the pack together.
And finally, I was not clear before on what type of plastic to use form over the “quick and dirty” wooden male box mold. My choice would be glass reinforced polyester resin, “fiberglass” because mounting flanges could easily adapted for indiviual mounting locations.
Mark Yormark
..
Mark, a direct link is inside the parentheses.
(http://s158.photobucket.com/albums/t103/caolivieri/Battery%20Pics/)
It is a 1P7S battery. But the molds would lend themselves to any configuration. I have a list of things I want to add to the drawing and I think one change will be making the side and bottom removable. The tabs and clamping plates are housed in the top mold. I did not intend to fold the tabs because the total height would still be shorter than CALB130’s.
Me, using cast-able silicone resin? No chance. Sorry folks 🙂
You worry about vibration but allow movement with the resin, Mark.
My efforts are rock solid and seal 100%
Hi Jack,
When you get your flat pack done are you planning on charging the two battery packs in parallel? Are there any potential problems to look out for with parallel packs joined only at the ends?
Hey Zak,
Jack said every individual cell is packed from hundreds of leaves of cells all in parallel…. And the Voltage is similar across differing packs. So what is there to worry care about?
Only future action packed episodes of EVTV will reveal the truth!
Yes, of course we will charge and discharge in parallel. Actually, I will have a switch to cut in the second pack and cut it out, and indeed, we can turn off the existing pack and run only on this new auxiliary pack.
The heart of your question is will they effectively parallel. The answer is a qualified yes. Intrinsically, all batteries are parallel already. An individual cell is actually made up of hundreds of paralleled cells. They work it out.
In this case, we have an interesting anomaly. The A123 pack can put out much more power than the CALB cells, conceivably 1400 amperes for A123 and 1000 amps for the CALB. On the other hand, the CALB cells have a higher energy content than the A123, with 180-190Ah in the CALB and 55 in the A123.
The net effect is a bit of a hybrid. THe A123 should provide instantaneous power, while the CALB should provide range. I’m hoping for the best of both worlds.
We have experimented in the lab a bit by paralleling a CALB battery with an A123 battery with an AH and AMP meter on both while charging and discharging. Substantial inequities occur and we wind up with corrective flows between the batteries.
My sense is the driving cycle is forgiving enough to accommodate this. The cells do equalize, but it does take a few minutes.
Hopefully we can answer some of these questions more definitively with some test drives. I’m kind of confident the answer is that it is just no problem no matter how you drive or charge it.
Jack Rickard
Watching the “to & fro'” of the relative current between CALB’s & A123’s through different driving ranges might be fascinating. Love stuff like this.
An analog ammeter showing this while driving would be a hoot!
Jack,
At this point I think some calculations may be in order.
If the two packs have the exact same nominal voltage then the A123 pack, since it has a much lower IR, will provide most of the current and therefore drain first until it hits the knee and its voltage is enough lower than the CALBS to allow significant charging from them. This would mean the A123 pack could bounce along the bottom and only slowly charge from the CALBS.
If, on the other hand, the CALB pack had a slightly higher nominal voltage (add one or two cells), then it would charge the A123 pack as soon as the A123s came off of the top of their charge and at a much higher rate. Crunching the numbers on this should be fairly easy if you know the IR numbers and expected discharge currents.
Just typing myself smart here.
David Seabury
You sure are David. But you didn’t show your work.
It’s an analog and continuous process.
Jack
OK,
In a vain attempt to justify my earlier post, and provide some numbers, I looked up the IR values for the CALB 180AH ~.7mOhm vs. A123 20AH ~1.1mOhm. Now I am more confused than ever! The A123s actually have a higher value, yet in your testing you find them stiffer. Can you explain this?
I know the values given are typically AC impedance values at 1Khz. How does this compare to simple DC values given by looking at the voltage drop at say 1C and calculating by V/I. Sorry if am ignorant on the subject I really just want to understand.
Thanks.
David Seabury
This is why I don’t like discussions of internal resistance. THERE IS NO internal resistance. There is an “equivalent series resistance” apparently. It’s actually a chemical process and the difference in teh cells is a matter of diffusion delay.
But in explaining it, and one of the reasons I don’t like talking about it, is we are in a little past my paygrade here.
In any event, they will certainly put out power unequally, and also store energy unequally. But as they are connected they work it all out over time. And it is very little time. So my sense is it won’t be a problem.
In actually practice you can parallel lead acid, AGM, lithium and all sorts of cells and get quite away with it. I recommend none of that, but I’ve seen it done in most horrible ways.
Jack
Hi Jack,
It’s battery circuitry all over the place!
I see semiconductor fuses on ebay, what’s the difference between a “semiconductor” fuse and a “regular” fuse?
Fuse mid pack, pros/cons?
Metallic fuses have a currnet carrier that melts at a certain current level.
Semiconductor fuses are P/N doped silicon and more gradually deteriorate from high currents until they basically develop heat and blow. THink of it is a time delay or “soft” current limits.
They can quite exceed their ratings for brief periods but continued use over the limit will cause them to blow.
Jack
Do they have a polarity?
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Jack I thought semiconductor fuses tend to blow quickly.
Ah crud, then I see Jack’s post! I don’t see how to delete my post, please feel free to delete this post and my previous one.
Hello
Semiconductor fuses “blow” faster in case of short circuit , so they are made to protect power electronics, like an inverter and/or controllers in electric vehicles.
Semiconductor fuse is the name for the application of the fuse, I found a good document about this
http://www.europowercomponents.com/media//s/e/semiconductor_fuse_application_guide_1_.pdf
I stand corrected all around. Great document. I’ve been trying to find more information on fuses. What method do you use for sizing these new Q fuses Celso?
Jack Rickard
Jack and Brian,
Just wanted to comment that you guys are getting much better at this shipping thing. Got my J1772 plug in connector. Very nice piece of work. Well worth the price. Now you can say you are officially in the EV business. Glad to do business with you. Wish all businesses in the US worked like you guys.
Pete 🙂
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I quite remember that WE ALL GAVE YOU the SAME SUGGESTION but you do not do the same and feel it is a moronic idea. Hell not only that, we gave you a few business plans that any one can do and GAVE it to you and you threw it away as a moronic idea. How does it feel that someone else is doing what you so much can’t do.
Indicating that we got one piece of kit in the right box and delivered to the right guy the first time – ONE TIME IN A ROW. Well we’re improving then. Gotta love it.
Yes, they are very nice. Kerzel does a great job with them, but each is kind of hand crafted. What you have is a collectible piece of artwork. We sold out in one day – hit output for the month.
Hopefully another 20 by the end of May. I think it dresses upl the connector a right smart. I wholeheartedly think everyone should adopt J1772. I know you already have a charge station for your Leaf.
But this is destined to be a distinctive bit of jewelry for your bold because the guy just can’t make enough of them for it to be anything but a rarity.
Rod Holshouser mounted one behind the fuel door on the Escalade that I would put up against any OEM car installation. Obviously we have a black and chrome thing going on with the vehicle already so it isn’t hard to imagine this thing fitting in.
But we are publishers and already hopelessly inept at shipping components. Brian and I stumble around the shop with these orders hardly knowing what to do with them. We are learning where to buy BOXES and TAPE and that sort of thing. It is comical.
Jack
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Jack,
A traditional Finnish sauna is a good place to think about the meaning of life and batteries. This time while throwing water on the hot rocks and waiting for the thermometer to go up to 80 degreess Celsius I wondered about how one would go about knowing when a battery pack had lost some of its capacity when one was using the bottom balancing method you’ve made us believers of. Let’s say you have a 55Ah pack and you keep using it for years and always topping it at a certain voltage. Then one day you end up using the whole 55Ah, but the batteries won’t keep up. Do you oversize the battery and actually not use all of it (55Ah really had 65Ah capacity thus giving you 10Ah to loose over time) or do you have to keep checking the voltage of the empty pack or individual cells and then adjust your fuel gauge to less Amps?
Jarkko Santala, Finland
It’s actually a good question. And it comes up rather sooner than when the batteries wear out. You get dramatically less AH during cold weather below 32F/0C than you do in warm weather.
On the Escalade, we are going to heat our batteries because we specifically want to use this truck during the bad months of winter. But our other cars do not have heated batteries.
We monitor voltage as well as AH. If our static voltage, that is our voltage at the stoplight after 15 or 20 seconds with no load, has reached 3v x N cells we know we have a couple of blocks of battery left. In cold weather, we learn that this occurs 10-15% sooner than in warm weather. And so on the Speedster for example, we start out at 120v. But if we get to 114 volts static, we know things are going bad quickly. And at about 110 volts, we are looking for a plug. 3 x 36 is 108v. We do NOT want our car to go below 108v static.
It will sag much beneath that under acceleration. We are mostly concerned with static. When I say 108v, I would note that the distance from 114 down to 108 isn’t very far – a few miles.
So you learn this over time.
Bottom line is we use a combination of odometer, AH, and pack voltage to monitor the state of our pack. ANd it doesn’t take very long for us to work this out.
As a matter of allowing others (daughters) to use our car, we normally have a limp mode set for 80-% discharge. This leaves a pretty good pad even in cold weather.
So these are our survival strategies. By the way, I don’t think they would vary very much if we top balanced instead. We would just be MORE likely to damage cells at the bottom.
Jack
We regularly have around -25°C/-13°F in the winter so it’s definitely an issue here as well. What I’m hoping to convert is a motorcycle so it shouldn’t be a problem for me. Having said that I did set out on a trip that ended in 3°C/37°F, but I’m trying not to make a habit of this.
The JLD404 seems quite a capable device for controlling a lot of things including cutoff at dangerously low voltage, but it probably wouldn’t withstand motorcycle conditions would it?
Jarkko
Jarkko
The jld404 is great but cant discriminate between voltage static vs under load (or they are hiding this in those chinese menus). So it wont really do as a limp-mode starter.. The soliton controllers do allow dual low-voltage settings from firmware 1.4 onward. Not sure if the jr. fits your bike though…
Not to mention that would be a fly vs. bazooka scenario… Way too much controller for a motorcycle conversion.
IIRC to use the JLD404 for limp mode, set the cut-off voltage to empty minus load, then set it to turn back on above the empty static voltage.
In the case of an Alltrax or Curtis controller (cheaper and more appropriate voltage ranges for motorcycles), employ the old resistor to the throttle input trick used on previous EVTV conversions.
Jack,
Not sure why you need a diode on the Mega pack if it already has a bridge rectifier on it? Should do the same thing.
Good point. Proably would not apply to the CHennic’s but yes, we do have a rectifier in the Megapac. Oddly, we also have a bit of a coil. The electric fan is driven by the AC input before it is rectified.
Jack Rickard
How does the AC fan like DC?
A non rotating core. 😉
Hi Jack,
With the twin controllers in the escalade are you running the throttle inputs in parallel by splitting the output of the throttle logic to both controls or are the controllers setup in a master/slave arrangement where only one controller is fed the information?
If needed is there a device that can take the output from a hall effect throttle and output two isolated outputs that are equal?
Jack,
For your throttle control op amp (741?) voltage follower you may want to add a 100K or so to ground just incase your input floats. Not sure where this would float to if left open and I am not sure you would want to find out the hard way.
A floating input to 450 horsepooer of rampant Escapade. Jack and Jim clambering through the back window for the isolator. That’ll be fun!
Good advise…. I would also make sure it is a Rail to Rail OP Amp…
The LM741 is a poor choice. It does not have rail to rail inputs or outputs. You have to provide a negative power supply to get the 741 operate linearly in the 0 to 5 volt range.
Did anyone notice that 100 ah pouch cells are now available from Shenzhen Victpower Technology Co., Ltd.?
http://victpower.en.alibaba.com/product/450940161-210447990/3_2V_100Ah_LiFePO4_battery_cell_for_EV.html?tracelog=cgsotherproduct1
They quoted me $195 ea. for 100 pieces, not a winner.
Worse, it appears to be 1.5C continuous and 3.0 C peak. And they are of course gynormous.
Jack
Jack,
How many amp is Kerzal’s J-1772 piece of jewelry?
And also they are the same height as the prismatics, no win there also
40 Amps. http://modularevpower.com/J1772_connectors.htm
He told me the aluminum billet version was good up to 50 amps.
We’re using it on the Elescalade with a 75 amp charger. But we terminate the wires on a block after about a foot and use 4Awg from there to the charger.
J1772 typically comes in 32 or 70 amp. The limitation is usually in the wiring of the plug, not the inlet. All J1772 pins are the same size of course.
Jack RIckard
Jack Rickard