Sport EV & delivery EV

[liveforphysics]

Are you sure that this is possible? What if I pull 2000Amps out of that pack? I assume that the TS cells would sag below 1V and be permanently damaged.

Btw. People think that TS cells are worse than there really are. They are just fine for the price. Cars are different than bike, most of them don't need over 3C since they are used as commuters. A car needs a lot of batteries so the price is very important. I have to add +50% of the purchasing price for duties and shipping!

Each 20Ah A123 cell you add in parallel with your pack will increase your current ability by 600amps continuously. They only weight 480grams per cell. If you want to pull 2000amps continously, you would need to run 2-3 A123 20Ah pouch cells in parallel with your pack.

The beauty of connecting them in parallel with your existing cells is that your TS cells wont have damaging voltage drop and heat going to them anymore. The voltages between the A123 cell and the TS cells will be linked, so the low Ri of the A123 cell protects the TS cell, and in return, the TS cell is constantly charging up the A123 cell. Cheap energy storage from TS, and high power output from the A123 cells.

Aviability of A123 cells? Are you speaking about these Chinese ebay sellers?

Nope, we're talking factory sealed boxes of new 20Ah A123 cells right from the manufacture. There are zero manufactures in the states using these cells, and they are made in Korea. This means it's very difficult to obtain them in the states, as A123 has no commercial reason to even have them in North America.

The only OEM using (and only large volume use) of these fantastic cells is the Shanghai electric car company in China. This is the best country they can be in as far as the cells making there way into the hands of the grass-roots EV community.

All rotating parts have to be balanced right on the shaft since the motor is not perfect. I even had to mount "only" one motor for now since the motors vibrate at high RPMs if coupled together. I will rebuild all the "non-electric" parts of the motor (housing, shaft...) later and then build in both motors.

When I saw the parts layout, I wondered if that wasn't going to happen. You were smart to use the clutch, and it functions as a torsional and axial alignment issue fix between the motors and tranny. To couple a motor to a generator, they always use a flex-plate setup, or those little laminated bolt-on torque strips like you see holding the friction plate in place in a pressure plate. Those are the space-saving thin methods. Other methods include a hundred varieties of off-axis coupler designs, but these all take up at least 6" of space for fitment, which would suck for this application. I've never seen direct-direct work-out in real life without destroying bearings. It always looks the best on paper... but paper is easy to fool.

 

[CroDriver]

http://www.youtube.com/watch?v=XqBXQ1lq0PE

 

[CroDriver]

Ooops, I just saw your post Luke, didn't noticed it before

Each 20Ah A123 cell you add in parallel with your pack will increase your current ability by 600amps continuously. They only weight 480grams per cell. If you want to pull 2000amps continously, you would need to run 2-3 A123 20Ah pouch cells in parallel with your pack.

The beauty of connecting them in parallel with your existing cells is that your TS cells wont have damaging voltage drop and heat going to them anymore. The voltages between the A123 cell and the TS cells will be linked, so the low Ri of the A123 cell protects the TS cell, and in return, the TS cell is constantly charging up the A123 cell. Cheap energy storage from TS, and high power output from the A123 cells.

Are yo aware of someone who actually made such a pack? Sounds great, I have to get a few of this new, large-format A123 cells and test them paralleled to a TS cell.

Nope, we're talking factory sealed boxes of new 20Ah A123 cells right from the manufacture. There are zero manufactures in the states using these cells, and they are made in Korea. This means it's very difficult to obtain them in the states, as A123 has no commercial reason to even have them in North America.

The only OEM using (and only large volume use) of these fantastic cells is the Shanghai electric car company in China. This is the best country they can be in as far as the cells making there way into the hands of the grass-roots EV community.

I'll hope that some of them will find their way to me for a reasonable price. Such a shame that there is no EV activity in Europe so I can't make bulk orders

When I saw the parts layout, I wondered if that wasn't going to happen. You were smart to use the clutch, and it functions as a torsional and axial alignment issue fix between the motors and tranny. To couple a motor to a generator, they always use a flex-plate setup, or those little laminated bolt-on torque strips like you see holding the friction plate in place in a pressure plate. Those are the space-saving thin methods. Other methods include a hundred varieties of off-axis coupler designs, but these all take up at least 6" of space for fitment, which would suck for this application. I've never seen direct-direct work-out in real life without destroying bearings. It always looks the best on paper... but paper is easy to fool.

This bolt-on setup could work but the flanges of both motors would have to be perfect. And the motors would need a very solid housing since two 11" DC motors are not very light (160 kilos).

I still haven't decided what I will do to couple those two motors together. I will leave this one motor as it is for now since the TS cells can't kill it anyway

Thanks for the very good information Luke

 

[CroDriver]

I had some cool stuff lying around so I thought I'll just take some photos:

A brand new Zilla Z2K EHV is in the box

I have tons of other stuff in the shop but this just looked so nice on the table

 

[jorhyne1]

Are those the new cells that Liveforphysics recommended to you? If so are you going to try to parallel them with the Thunderskys? I'd be very interested to hear about your results.

 

[CroDriver]

Are those the new cells that Liveforphysics recommended to you? If so are you going to try to parallel them with the Thunderskys? I'd be very interested to hear about your results.

No, this are cell_man's 30C capable cells. They will get into a new car. The BMW will probably get Headways by the end of the year

EDIT: Yup, Liveforshysics recommended these cell. He talked also about some Li-po cell so I got a little confused

 

[vanilla ice]

Somebody needs to run some high load tests on one TS cell paralleled to one of those. That would be a pretty damn affordable way to get big cap and big C together. If it works well.

 

[CroDriver]

Somebody needs to run some high load tests on one TS cell paralleled to one of those. That would be a pretty damn affordable way to get big cap and big C together. If it works well.

You guys really think that this could work?

I can try it... I mean, I WILL try it.

But I will have to build new copper bars for the TS cells. The current copper bars are too thin.

EDIT:

ONE of "those" won't be enough. I need at least 1600 Amps, so I would need 3 paralleled 20Ah cells = 120 kg additional weight

 

[vanilla ice]

The only possible issue I can think of is if you dump the 30c pouch cell down to the bottom very quickly, what will the TS cell do? The big sag should (I think) prevent it from over working itself trying to dump current into the pouch. Any case Phys seemed to think this would work fine.

 

[CroDriver]

The only possible issue I can think of is if you dump the 30c pouch cell down to the bottom very quickly, what will the TS cell do? The big sag should (I think) prevent it from over working itself trying to dump current into the pouch. Any case Phys seemed to think this would work fine.

That means that the pouch cell would experience one discharge/charge cycle every time I hit the throttle...

I can try it but I think it's not worth the effort. Maybe it would be worth a shot in another application or if I would build another car but I already have a custom BMS, custom battery rack etc. I would have a lot extra work...

 

[lutach]

You have a very nice project there. I'll be following this.

 

[oatnet]

Wow.

I love the dual-motor setup!

-JD

 

[lutach]

The dual motor set up is very nice. Do you have plans for a dual induction or brushless motor set up?

 

[CroDriver]

The dual motor set up is very nice. Do you have plans for a dual induction or brushless motor set up?

Thanks.

I wanted a dual AC motor from AC Propulsion or UQM first but they are hard to get so I choose DC

Do you have some more info about that setup you posted?

I'm defiantly planing a AC powered car but it has to wait for now.

 

[lutach]

Hope that helps. I'm actually planning to build a race car. I'll post more info as I go along.

 

[CroDriver]

Hope that helps. I'm actually planning to build a race car. I'll post more info as I go along.

Looks good.

Is this a motor + inverter system or just the motors?

Who is selling those?

 

[lutach]

Hope that helps. I'm actually planning to build a race car. I'll post more info as I go along.

Looks good.

Is this a motor + inverter system or just the motors?

Who is selling those?

I'll get more info for you. I do know of a place that can do the inverter if that system doesn't include it. The only problem will be the MOQ, so let me talk to the manufacturer of that system to see if one can be bought for testing before I mention who sells it.

My plan is to revive a early 90's project that if it was still going, we would be looking at some very high tech electric drive system. The company that made that system said a more powerful unit can be made. My main goal is to make a few vehicles to showcase various set ups and hopefully in the process set some records.

 

[lutach]

As you can see from that file, the inverter is capable of 1700HP. Now the reason they only posted HP rating is due to the fact that a lot of people still don't get the Kw rating to compare against the HP and in the early 90's they said it was very true, so they used the HP rating instead .

 

[lutach]

CroDriver,

How reliable are the motors you have?

 

[CroDriver]

http://www.youtube.com/watch?v=0eBw8I_4jtE&feature=player_embedded

 

[lutach]

Nice. I can't wait to see the full potential of the set up.

 

[CroDriver]

CroDriver,

How reliable are the motors you have?

Hi lutach

I have no idea since I don't have them long enough. They should be very reliable since there is nothing that could break

John Wayland raced one Kostov 11" (old, low voltage model) for one year in his White Zombie and was very satisfied with the motor until it blew up because he was burning the tires over 20 sec. standing still

 

[BMI]

The dual motor set up is very nice. Do you have plans for a dual induction or brushless motor set up?

Thanks.

I wanted a dual AC motor from AC Propulsion or UQM first but they are hard to get so I choose DC

Do you have some more info about that setup you posted?

I'm defiantly planing a AC powered car but it has to wait for now.

CroDriver, if you want an AC motor I can suggest a possible option which you might like to look into. It is made by a very specialised motor company which you probably know nothing about. The motors are custom made here in Brisbane, Australia. These motors are rated at 200kW and is much lighter in weight than a UQM motor since it is an ironless motor. Like the UQM motor it is also liquid cooled and you need to use the Tritium Wavesculptor controller/inverter supplied with the motor. This controller is specially manufactured by a separate company to work with this electric motor.
One of these motors was fitted to a Honda Civic which travelled across Australia last year as part of the World Solar Challenge from Darwin in the north to Adelaide in the south (more than 3000km).
I personally saw this motor test running in the companies workshop recently and it is as smooth as silk. Below are a couple of photos of the Honda Civic and a view of the motor and controller inside the engine bay.
I will be working with this motor manufacturer and supplying our high power LiFePO4 batteries (up to 35C discharge) for a few projects so hopefully you will see a few cars with this motor on the road before the end of the year.
I can put you in touch with the motor and controller manufacturers as well as the owner of the Honda Civic running the motor if you are interested in more information

 

[voicecoils]

CroDriver, if you want an AC motor I can suggest a possible option which you might like to look into. It is made by a very specialised motor company which you probably know nothing about. The motors are custom made here in Brisbane, Australia. These motors are rated at 200kW and is much lighter in weight than a UQM motor since it is an ironless motor. Like the UQM motor it is also liquid cooled and you need to use the Tritium Wavesculptor controller/inverter supplied with the motor. This controller is specially manufactured by a separate company to work with this electric motor.

Relevant details:

Ultramotive: http://www.ultramotive.com.au/

Tritium: http://www.tritium.com.au/

In 1995, a group of undergraduate
engineering students at the University of
Queensland formed a team with the aim
of building Australia’s fastest solar car.
With minimal budget, no industry or
academic supervision, the team designed
and built a car run entirely on the energy
from the sun, and entered it in the world’s
premier vehicle race – the World Solar
challenge in 1996. Several Brisbane
companies have emerged due to this
success - Tritium Pty Ltd (high power
electronics) & Ultramotive Pty Ltd
(efficient motor design).

Source: http://ausinnovation.org/SiteCollectionDocuments/2009 AIF Report - 17909.pdf

And, since you're on AEVA too, Tritium_James is someone to look out for.

 

[CroDriver]

Thanks for the input guys!

I'm already in contact with a few companies that are building/developing high power AC motors/inverters but this looks best so far.

I will definitely contact them