[sifawangiaEV]

Hey DIY Community!

I just purchased the donor vehicle for my conversion: a 2006 MINI Cooper S. I've started taking out the engine and plan to finish that by the end of this week. I'm completely new to the automotive and electrical field but I'm completely willing to learn and grow. My budget for this build is $5000 but I'm realizing that I might end up spending $7000 for everything.

This conversion will be using a Netgain Warp9 DC motor, a Zilla 2K controller, and 4 Tesla battery modules wired in series stuffed in the trunk, if I can get my hands on some. My system voltage will be about 96V and will have 250 amp hours. I want to get at least 60 miles of range and be able to safely cruise on the highway, so a top speed of about 75 mph. I'm hoping to get the Tesla batteries either off eBay or from a Copart auction near me. I'm hoping that Copart is reliable enough because I've come across some pretty sweet deals on there.

I'll continue to give updates on this thread but I'm also going to be creating a blog, so I'll post updates here for that as well.

 

[NewbieEV]

Hey DIY Community!

I just purchased the donor vehicle for my conversion: a 2006 MINI Cooper S. I've started taking out the engine and plan to finish that by the end of this week. I'm completely new to the automotive and electrical field but I'm completely willing to learn and grow. My budget for this build is $5000 but I'm realizing that I might end up spending $7000 for everything.
View attachment 122818
This conversion will be using a Netgain Warp9 DC motor, a Zilla 2K controller, and 4 Tesla battery modules wired in series stuffed in the trunk, if I can get my hands on some. My system voltage will be about 96V and will have 250 amp hours. I want to get at least 60 miles of range and be able to safely cruise on the highway, so a top speed of about 75 mph. I'm hoping to get the Tesla batteries either off eBay or from a Copart auction near me. I'm hoping that Copart is reliable enough because I've come across some pretty sweet deals on there.

I'll continue to give updates on this thread but I'm also going to be creating a blog, so I'll post updates here for that as well.

Nice looking car for EV!!!!. By the way, may I ask?
How did you choose the motor and the battery in cluding the controller to satify your performance need?
I am in the planning stage of doing the conversion to meet quite similar performance

 

[sifawangiaEV]

How did you choose the motor and the battery in cluding the controller to satify your performance need?

First, I looked for a motor that had a good horsepower rating, good rpm, had a large enough diameter, and weighed roughly 150 lbs. This motor has a hp rating of 32, a max rpm of 5000, a 9 inch diamter, and weighs 165 lbs. The rpm ensures that the car can reach a good top speed and the hp rating, diameter, and weight ensures that the motor can actually move the car, so the larger these three factors are, the larger the car the motor is able to handle.

After deciding the motor, I had to find a controller that can handle the voltage and amp ratings of this motor, which, for this motor, is 72 - 156 V and 400 amps, respectively. The Zilla controller I picked can handle this perfectly; its max amp rating is 2000A and voltage capacity is 72 - 300 V. This controller can also HAS to be able to handle the type of motor you choose, so for me, it needs to be a DC controller because my motor is a DC motor.

Hope that helps : )

 

[DansEVhobby]

sounds awesome!
why did you decide on the 2k amp controller? I'm just starting to learn about this stuff, but it seemed to me like the 1k controller had plenty of capacity for your battery/motor setup.

 

[sifawangiaEV]

why did you decide on the 2k amp controller? I'm just starting to learn about this stuff, but it seemed to me like the 1k controller had plenty of capacity for your battery/motor setup.

Yes so a 1k amp controller would be plenty enough but I came across a good deal for the 2k and I couldn't pass it up. The 2k controller would also give me room to grow and upgrade to better higher amp/voltage parts in the future.

 

[sifawangiaEV]

Hey everyone,

I am happy to announce that the engine is out of the car!! I took me some time, but I'm just overwhelmed with relief that I was able to get it out. I learned a lot about the car in this long process and I feel more able to take on the giant task of this electric vehicle conversion.

Check out my blog about the engine removal process if you want a more detailed look on how I took the engine and all of its parts and accessories out: DIY Electric Vehicle Diaries #1.

My next step is to attach my Warp9 DC motor to the transmission. I'll send updates on how I'm crafting an adapter plate, what coupling I'm using, and how I'm going to align everything so there's no shaking/scratching when the motor turns. I'm also going to install the vacuum pump next week and I need some help on its placement in relation to the pressure switch and reservoir. Here's a diagram of what I'm planning to do (please tell me if there's anything I should do differently):

I've heard some people mention check valves but my pump didn't come with one. Should I get one or will everything work fine without it?

I'm also doing some bench testing this week on all of the electrical components used for my Z2K controller. I'm running all of these tests using a 12V battery but, looking into the future, I'm wondering how my ECPC404 digital meter (knock off JLD404) is going to tap off of my 96V load. In the image below it shows a wire going directly from the high voltage wiring to the digital meter but I'm scared that's going to blow my meter. The manual for the JLD404 says "It should be apparent from the drawing that your high-current load does not go through the meter. Instead it is sensed via the shunt at 9 and 10." I'm a bit confused as to what I'm supposed to do here with (what seemed like) a HUGE contradiction so help is greatly appreciated.

 

[DansEVhobby]

So the plan is to go with a separate 12v bat to run accessories and lights or going to be running a dcdc converter?

 

[schelle63]

Shunt (electrical) - Wikipedia

en.wikipedia.org

12V:
All controllers (and DC-DCs) that I know need a power supply in order to start, which is usually provided by the car's 12V system. With a battery only, you will need to (manually) charge it regularily, which is ok for temporary test or building phase.
But I am sure You don't want to do this in a car you are using every day, or for a longer period; the DC-DC will do that automatically, like the alternator does in an ICE-car.

 

[sifawangiaEV]

Shunt (electrical) - Wikipedia

en.wikipedia.org

View attachment 123037

12V:

I understand the purpose of the shunt and its placement in my circuit but I'm confused about the line that goes from the high voltage wiring to pin 6 on my meter. Do I just need to wire a line from one of the contacts on the contactor to pin 6 on my meter? Will this be safe?

 

[schelle63]

Assuming that the thick black line from the battery pack is "minus" and the red line from battery pack is "plus" (and further assuming that the wiring diagram is correct!), everything is clear:

- Pin6 is not connected to "one of the contacts" but to "battery pack plus". A small cable diameter will be sufficient. If it makes You feel better, you can even insert a tiny fuse (start with 100mA).

The JLD404 wants to know the battery voltage, that makes sense.

 

[EVTJ]

Subscribed

 

[reiderM]

I have some potentially good news for you. You can push out a lot more than 32 hp with that motor for short periods of time. The controller you have is rated for 2000 amps, so hypothetically you could run 2000 amps thru the motor. Of course this would probably cause some issues, but it could work in theory. More realistically, you could run 1000 amps for short bursts of acceleration.

The biggest limiting factor for these type of DC motors is heat, since pushing more current thru them generates more wasted energy in the form of heat. If you force airflow thru the motor to keep it cool, you can get quite a bit more power out of the motor than what it's officially rated for. A neat perk of brushed DC motors.

 

[sifawangiaEV]

I have some potentially good news for you. You can push out a lot more than 32 hp with that motor for short periods of time. The controller you have is rated for 2000 amps, so hypothetically you could run 2000 amps thru the motor. Of course this would probably cause some issues, but it could work in theory. More realistically, you could run 1000 amps for short bursts of acceleration.

The biggest limiting factor for these type of DC motors is heat, since pushing more current thru them generates more wasted energy in the form of heat. If you force airflow thru the motor to keep it cool, you can get quite a bit more power out of the motor than what it's officially rated for. A neat perk of brushed DC motors.

That sounds good but I'm wondering if my potential 4/0 cables (I'm having some trouble choosing the right cables) will do for that current (ie. not blow up). Also the motor is rated for 500A and I'll probably set my zilla to limit the top current to 450A to protect the motor but I'll look more into that and motor cooling for higher performance.

 

[reiderM]

That sounds good but I'm wondering if my potential 4/0 cables (I'm having some trouble choosing the right cables) will do for that current (ie. not blow up). Also the motor is rated for 500A and I'll probably set my zilla to limit the top current to 450A to protect the motor but I'll look more into that and motor cooling for higher performance.

If anything, 4/0 cables are overkill. 4/0 cables have a cross-sectional area of 107 mm2. To put that in perspective, Tesla uses 50 mm2 cables for everything high voltage. 2/0 cables would likely be more than enough, and with 4/0 I'd say you have absolutely nothing to worry about. I haven't heard of anyone using 4/0. 2/0 welding wire, or 2/0 shielded wire are what almost everyone uses it seems.

Keep in mind that the super high currents you may push through them are only for short bursts. There isn't really a scenario where you would sustain >1000a through the cables for more than about 10 seconds.

Don't limit to 450A. Configure a thermistor to only limit amperage when operating temperature exceeds some set threshold.

Motor cooling is essential if you want to get insane performance out of DC motors. Here is a great thread I found about the topic that has all the info you will need.

 

[sifawangiaEV]

Small update: currently having trouble with the HEPI input with my Z2K controller.
Link to thread: Zilla 1233 HEPI and 1231 Error

I've also received 4 tesla battery modules, and an orion BMS. I was ready to hook everything up when a flex cable on one of the modules torn, which had all of the voltage taps of the 6 cells in that battery module. Currently working on fixing the flex cable DIY so I can hook up the BMS to all of the cells and get everything ready to put in the car.

Also received a tesla coolant pump and reservoir. Just need to buy some 3/8 inch coolant pipes to connect it to all of the batteries.

 

[brian_]

I just skimmed through the whole thread to date, and didn't see any discussion of the mismatch in voltages in the original description...
a Tesla Model S/X module is 6S, for a nominal 22 volts. Four of them will run (nominally) 88 V; 96 V is at the high end of charging, not what is going to be available in operation.

 

[sifawangiaEV]

I just skimmed through the whole thread to date, and didn't see any discussion of the mismatch in voltages in the original description...
a Tesla Model S/X module is 6S, for a nominal 22 volts. Four of them will run (nominally) 88 V; 96 V is at the high end of charging, not what is going to be available in operation.

Oh yeah that makes sense. I did realize this but I'm okay with that since I'm not that worried about top speed all that much, only want enough to go on highways which I believe I can do with such a light weight car. The cells have a good range from 22 to 24 volts, so I'm hoping to have the use of the full 96 volts sometimes, if that makes sense. As of now the cells read 23.1V each which I'm totally fine with.

 

[sifawangiaEV]

The cells have a minimum of 18V so would I program my can-enabled charger for 72V, 88V, or 96V? I was thinking 96 since that's the max. Is that correct?

 

[brian_]

The cells have a minimum of 18V so would I program my can-enabled charger for 72V, 88V, or 96V? I was thinking 96 since that's the max. Is that correct?

That depends on what "96V" means to the charger.

• If it means that the charger will not exceed 96 V, that might be suitable.
• If it means that the charger will run to voltages suitable for a nominally 96 V lead-acid battery, it will go far too high in voltage for a 24S lithium-ion battery; a charger programmed for a nominally 96 V lead-acid battery (48S of nominally 2V cells) will typically reach a maximum charging voltage of 104 to 112 volts.

If the charging settings are for nominal lead-acid battery voltages, the "88V" setting might be suitable.

 

[cricketo]

Yup, what Brian said. Need to understand the terminology/specs of the charger first - it may be referencing the nominal voltages, or the max voltages.