[highamperage]

Hello! I'm eager to get my feet wet in the EV conversion world. Been running numbers for a while, but am getting closer to actually doing it. I love trucks, and EVs.. so I was looking at converting a 2008 Silverado Extended Cab I see which has no engine and is available at a good price.

I need some advice. I was looking at going with either a
-Warp13 with Warpdrive 160v 1400a controller
or
-Warp11HV with warpdrive 260v 1600a controller.

I'm not sure which to choose. I see the Warp13 has a lot better torque numbers and since this a heavy truck that would be nice. But the Warp11 HV combo would have more total power due to the higher voltage capability. (Or can I run a Warp13 higher than 170volts?)

What do you guys think? This is not a dragster, however I do want pretty good performance - it should easily blow the doors off the ICE that was in there. Any thoughts are appreciated!

 

[LithiumaniacsEVRacing]

Your truck is very heavy, you need the torque. Go with the Warp13" with a Zilla 2k or Soliton 1 controller. If the Warpdrive 1400amp controllers are available they would work.

Hello! I'm eager to get my feet wet in the EV conversion world. Been running numbers for a while, but am getting closer to actually doing it. I love trucks, and EVs.. so I was looking at converting a 2008 Silverado Extended Cab I see which has no engine and is available at a good price.

I need some advice. I was looking at going with either a
-Warp13 with Warpdrive 160v 1400a controller
or
-Warp11HV with warpdrive 260v 1600a controller.

I'm not sure which to choose. I see the Warp13 has a lot better torque numbers and since this a heavy truck that would be nice. But the Warp11 HV combo would have more total power due to the higher voltage capability. (Or can I run a Warp13 higher than 170volts?)

What do you guys think? This is not a dragster, however I do want pretty good performance - it should easily blow the doors off the ICE that was in there. Any thoughts are appreciated!

 

[Yabert]

Check the number:
W13 = 170v x 1400A / 746 * 0.85 = 271 hp
W11HV = 260v x 1400A / 746 * 0.85 = 414 hp

HP it's the way to go because you can select a lower gear to have more torque at wheel whit a W11HV compare with a W13 at higher gear.
W13 probably have his peak torque a low RPM compare to W11HV they have peak torque at higher RPM.
HP = Torque x RPM / 5252.... So, torque over a wide RPM = more overall power!


To have this HP number, don't forget to buy a 25000$ battery pack!!!..

 

[highamperage]

Thanks for the feedback.

What's the. 85 in your math for? To take into account for inefficientcies?

Also can the warp 13 be run at a higher voltage? I was reading on here and heard of a kostov 13" motor but am not familiar with them...anyone know of a place that sells them?

I was looking at going with a 29kwh battery pack. Good thing is prices seem to be getting better all the time on this tech

 

[Yabert]

What's the. 85 in your math for? To take into account for inefficientcies

Yes.... those motors have around 80-90% efficiency.

The Kostov 13" 250v is a good choise if it can take 1400A. Especially if you think abuse often or work hard with your truck.
That will reduce the stess generate on smaller motor.
http://kostov-motors.com/tractionmo...ts/seriesdcmotorsforelectricvehicles/k13250v/

Rebirthauto.com seem a supplier of kostov motor.

Compared to Kostov 13" 250v or Warp 11" 288v the Warp 13 can't take high voltage because it don't have interpoles.

 

[tomofreno]

I was looking at going with a 29kwh battery pack.

You will need to size the pack not only for the range you desire, but also for the max power desired, since cells are limited in the current they can supply. If you use the large format or prismatic cells they usually are sized at a capacity of around 1/3 the magnitude of the current you plan to regularly use during acceleration for rated cell lifetime, so for example 1400A would indicate about 460Ah cells. Some size to 1/5 rather than 1/3, with unknown effect on cell life (unknown includes maybe no effect).

Some, like in the thread at the link below, use smaller cylindrical cells like Headway which tolerate much higher "momentary" discharge rate, like 20C. These are much smaller Ah capacity, so the pack is built of a large number of cells with x in parallel, and y of these x-size groups in series. The x variable is typically chosen as at least 1/20 the planned max momentary discharge current during acceleration since these cells are rated at around 20C max momentary discharge current (depending on manufacturer). Cells are typically about 3.2V nominal voltage, so a 260V pack would require about 260/3.2 = 81 prismatic cells in series, or 81 of the groups of x smaller cylindrical cells in series. Max current of 1400A would require x to be at least 1400/(20*C), where C is the cell capacity in Ah, and cells rated at 20C max current. If C is 10Ah, x is at least 7, so a pack of such cells would require at least 81*7 = 567 cells. Each group of x = 7 cells is 70Ah so the pack would be about 70*3.2*81 = 18kWh, which won't get such a heavy vehicle very far, so you would need to increase x considerably (which would also likely increase cell life). On the other hand, if you use 460 Ah prismatic cells for C = 1/3 max current, the pack would be 81*3.2*460 = 119kWh, and cost a fortune! If you size the pack for C = 1/5 max current, or about 280Ah, the pack would be around 72kWh and cost a smaller fortune but give good range for such a large vehicle (if you can find room for that many large cells, another consideration). You are also limited by exactly what Ah capacity cells are available. This shows some of the considerations.

Look at the "garage" here, and at www.evalbum to get an idea of what energy/mile larger vehicles require to get an idea of what energy pack you will require. Also Look at this thread to get an idea of what is required for a higher power, higher current battery pack using cylindrical cells:
http://www.diyelectriccar.com/forums/showthread.php/bmw-bi-moto-ev-project-28287.html

What you want to do can be done, but it will require lots of $.

 

[Yabert]

Ha! ha!...

Like tomofreno said, a 25000$ battery pack can give to you the possibility to have 400 hp / 400 lbs-ft, but with 35 miles range.... or far less if you abuse!

 

[highamperage]

I understand the battery pack issues mentioned, and I have yet to solidly determine which batteries I will use, but was looking at TS Lithium Batteries. I was under the impression these had a impulse (10 seconds) rating of 10C which would put my 30kw pack upto 300kw, enough for the quick off the stop light speed up. You're right I'm going to have to decided specifically which battery capacity to choose.

That said, 99.99% of the time I'd be driving around stress free on the pack at 25-60mph. Ha! How often in this city traffic nightmare can I get above 30? Anyway, I was expecting this vehicle to use about 500 watts/hour/mile when driving rationally (at 60mph). Do you think that is possible?

I was looking at the EV calucators available (Which seem to put it better than that?) (http://www.evconvert.com/tools/evcalc/) and doing my own math based on drag coefficient, frontal area, and rolling resistance. (Got the formula for that from a EV book), also seems to come out better than 500. It seems 500 would be a safe estimate.. but I really don't know. I just looked on the EValbum site and see a wide range of stuff. ONe large truck used 1040kwh/mile but, another seemed to use only about 350. All use lead batteries which will waste more power due to perkuet effect than lithium, and weight more. (Am I right?) Again, hoping 500... haha

 

[highamperage]

Ok guys how about this...

• Warp 13 Motor @ 170 volts
• Warpdrive 1400 amp controller (upgraded to 1600 amps)
• Thundersky 200AH batteries

According to currentEV tech (sponsor at the right) the Thundersky batteries can handle 20C burst rate. If I used 54 of those, I'd have a 34kw capacity, at 172 volts. At a 20C max rate, that is 680kw/4000amps. That should do the trick I think, as my setup above should not go about 272kW/1600amps due to controller limitations.

I don't think I can afford a Zilla2K for now, but could always upgrade later. We'll see anyway, maybe I can rob a bank, get a promotion or save a bit longer or something.

At 1400 amps, the Warp 13 should produce 614 ft/lbs torque, which is more than the ICE at any RPM.

What do you guys think? Am I missing something important? It sounds like this setup should be fun to drive as well, but I am new here -any input is appreciated!

 

[DavidDymaxion]

I've heard they can only do high current rates for a couple of seconds.

Also, don't forget voltage sag -- even if you could maintain 4000 Amps for a usable amount of time you are only going to get about 1/2 that power.

Jack Rickard is converting an Escalade http://evtv.me .

Ok guys how about this...

• Warp 13 Motor @ 170 volts
• Warpdrive 1400 amp controller (upgraded to 1600 amps)
• Thundersky 200AH batteries

According to currentEV tech (sponsor at the right) the Thundersky batteries can handle 20C burst rate. If I used 54 of those, I'd have a 34kw capacity, at 172 volts. At a 20C max rate, that is 680kw/4000amps. That should do the trick I think, as my setup above should not go about 272kW/1600amps due to controller limitations.

I don't think I can afford a Zilla2K for now, but could always upgrade later. We'll see anyway, maybe I can rob a bank, get a promotion or save a bit longer or something.

At 1400 amps, the Warp 13 should produce 614 ft/lbs torque, which is more than the ICE at any RPM.

What do you guys think? Am I missing something important? It sounds like this setup should be fun to drive as well, but I am new here -any input is appreciated!

 

[Duncan]

Hi High

Remember the controller is a power in - power out device and will drop the voltage to what the motor needs

So if you have a controller that can take 300v - use a 300v battery pack

When you are taking off the motor will only need ~30v so 1000 motor amps will only be 100 battery amps

As your motor speed increases the motor voltage increases - but you can't keep increasing the motor speed indefinitely (the comm explodes)

At 3000 - 4000 rpm your motor will need ~150v - so 1000 motor amps would be 500 battery amps

Don't worry about over-volting the motor - you can't.
You can only over-speed or over-current or a combination

 

[Yabert]

At 1400 amps, the Warp 13 should produce 614 ft/lbs torque, which is more than the ICE at any RPM

Why do you stick at Warp 13 motor?? Lets compare:

Warp 13: 4825$, 367 lbs, 101 lbs-ft @ 300A, HP (170v, 1000A) = around 190 hp.

Kostov 13: 3800$, 308 lbs, 103 lbs-ft @ 315A, HP (240v, 1000A) = 270 hp.


Thundersky are rated at 20C for fraction of second only!!!!!!!
The Calb 180Ah or 130Ah can give 1000A for less than 10 sec continue. http://www.evolveelectrics.com/CALB.html

So you can set the controller at 1400A to the motor to have massive torque and set the batteries at 800A or 1000A to have great hp without burn the cells.

Here some number:

100 x Calb 180Ah = 320v nominal and 57.6 Kwh for 24300$
Internal impedance 0.0006 ohm x 1000A = 0.6v drop - 3.2 = 2.6v x 100 = 260v x 1000A / 746 x 0.85 = 296 hp

Well, massive start torque of 400-500 lbs-ft (from 0 rpm) and 296 peak hp seem good to me.
And like you said, 99.9% of time, you don't need more than 30-40 hp to move your truck.

 

[highamperage]

Hi High

Remember the controller is a power in - power out device and will drop the voltage to what the motor needs

So if you have a controller that can take 300v - use a 300v battery pack

When you are taking off the motor will only need ~30v so 1000 motor amps will only be 100 battery amps

As your motor speed increases the motor voltage increases - but you can't keep increasing the motor speed indefinitely (the comm explodes)

At 3000 - 4000 rpm your motor will need ~150v - so 1000 motor amps would be 500 battery amps

Don't worry about over-volting the motor - you can't.
You can only over-speed or over-current or a combination

Thanks for this! That is good to know.

That should help reduce the issue of voltage sag, right? If I am using a 320volt battery pack, but my motor maxes out at 250- even if the battery pack sags by 70 volts, I'll still will be able to achieve the 250? And.. I can put a parameter in the controller that will prevent over-revving/excessive voltage?

Regarding the NetGain vs Kostov issue, I was under the impression the Kostov wasn't as good of a motor... and can't handle large currents as well as a Warp13? The price different and voltage rating is very attractive though.

Thanks for all the comments. This is good stuff.

 

[Yabert]

Indeed, Kostov motors are lighter and probably contain less copper than the Warp motor because that must preserve the space between the stator coil to accommodate the interpole. But those one allow to use more voltage and less amps to create the same amount of HP.

My understanding of the warp 13 is that it's a large pile of copper and steel that can take LOTS of ampere continuously. That is exellent for a forklift operating 8h, but maybe less for an EV it running for 1 hour.

But because you prefer Warp motor, I have another motor choise to compare:
Many drag racer use two 9" motor in direct drive application.

2x Warp 9: 3500$, 300 lbs, 118 lbs-ft @ 300A, HP (340v x 1000A) = around 380 hp

From Evsource.com: Warp 9 @ 1400A can give 340 lbs-ft x 2 = 680 lbs-ft.


All this is too much theorical.....
Good luck with your project.

 

[Woodman]

Re: Motor Selection for Truck Converison

Would a forklift motor be suitable with a Chevy S10?

 

[highamperage]

Hi High

Remember the controller is a power in - power out device and will drop the voltage to what the motor needs

So if you have a controller that can take 300v - use a 300v battery pack

When you are taking off the motor will only need ~30v so 1000 motor amps will only be 100 battery amps

As your motor speed increases the motor voltage increases - but you can't keep increasing the motor speed indefinitely (the comm explodes)

At 3000 - 4000 rpm your motor will need ~150v - so 1000 motor amps would be 500 battery amps

Don't worry about over-volting the motor - you can't.
You can only over-speed or over-current or a combination

When controllers are being rated, do they use motor amps or battery amps? I assume motor?