Basic noob question

[dwmollett]

I'm a bit overwhelmed with all the information here but... it's awesome!

My question: Is it possible to use the community edition Tesla SDU board (with Tesla SDU of course) but utilize Leaf batteries? Any builds where people have done this I can check out?

[johu]

yes but they are officially limited to 110kW so not quite for race cars but for normal road use with occasional bursts I'd say they suffice

[dwmollett]

Thanks for your reply.

How is charging of the Leaf batteries typically handled in this situation? Or more basically, what are the generalized connections to the various components of a Tesla Nissan combo?

[Boxster EV]

Thanks for your reply.

How is charging of the Leaf batteries typically handled in this situation? Or more basically, what are the generalized connections to the various components of a Tesla Nissan combo?

Welcome.

You have to consider that DC current to charge high voltage batteries isn't specific to a brand, rather the performance characteristics of the components in question. In most cases there will be a solution for overcoming any connectivity challenges between different brands of chargers and/or batteries.

Worth having a look through the project section to see what others have been doing on their conversion journey.

[P.S.Mangelsdorf]

Thanks for your reply.

How is charging of the Leaf batteries typically handled in this situation? Or more basically, what are the generalized connections to the various components of a Tesla Nissan combo?

Similar to Boxster's response, the project pages is a good place to start.

I find it useful to analogize an EV set up to a gas set up.
- A Tesla drive unit is your engine, transmission, differential, ECU, and fuel pressure regulator rolled into one
-the power cables are your fuel lines
-the battery is the fuel tank and fuel pump
-contactors and fuses are fuel shutoffs

Now, there are a lot of different fuel tank and engine combinations that will work. Some better than others, and in some cases you can push too little fuel, limiting power to an unusable level. But provided it gets the fuel, an ICE engine doesn't care if its a stock gas tank, a fuel cell, or a 5-gallon bucket. It doesn't care if it is a stock fuel pump or an aftermarket one.

Similarly with an EV, the Tesla drive unit doesn't care if the power is coming from Kia, Chevrolet, Tesla, Nissan, etc. All the drive unit cares about is:
-Is the voltage in an acceptable range
-Is there enough available current to generate enough power to move the car

A great resource on various batteries is Kerry Manning's Youtube channel EVEngineering. He has a spreadsheet comparing a variety of OEM batteries.


Regarding charging, the battery also doesn't care where the charge is coming from, provided the charger has been configured to the batteries' voltage and amperage needs. There are a wide variety of aftermarket and OEM options.

[dwmollett]

Great stuff, thanks to all of you for your posts. I'll certainly check out the resources each of you mentioned.

Is it safe to say that it's not a matter of "if" but "when" will the Model 3 be controllable via an open source Tesla board?

[P.S.Mangelsdorf]

Is it safe to say that it's not a matter of "if" but "when" will the Model 3 be controllable via an open source Tesla board?

It appears Damien is testing the newest version of the M3 drive unit Mod-board. So yes, it appears to be "when".

Now I just need to make some time to fit and test the new modboard....

[dwmollett]

I find it useful to analogize an EV set up to a gas set up.
- A Tesla drive unit is your engine, transmission, differential, ECU, and fuel pressure regulator rolled into one
-the power cables are your fuel lines
-the battery is the fuel tank and fuel pump
-contactors and fuses are fuel shutoffs

These are very helpful analogies. Let's assume I have a Tesla Model 3 rear motor (yup, I understand that Damien is not yet done with his magic) and a complete Nissan Leaf battery with the BMS, contactors, fuses, etc.

Wouldn't I also need the charger out of the Leaf motor stack?

Then the Leaf battery could be charged either by a level 2 charger (or DC fast charger) designed for the Leaf via the original charging ports?

Is it then correct to say that the Tesla inverter, with an appropriate Damien brain board, would communicate with the battery, hall effect throttle, brakes etc. to ultimately tell the Tesla M3 motor to take the watts required to move the car from the Leaf battery?

Thanks again for any information.

Kind regards

[arber333]

These are very helpful analogies. Let's assume I have a Tesla Model 3 rear motor (yup, I understand that Damien is not yet done with his magic) and a complete Nissan Leaf battery with the BMS, contactors, fuses, etc.

Wouldn't I also need the charger out of the Leaf motor stack?

Then the Leaf battery could be charged either by a level 2 charger (or DC fast charger) designed for the Leaf via the original charging ports?

Is it then correct to say that the Tesla inverter, with an appropriate Damien brain board, would communicate with the battery, hall effect throttle, brakes etc. to ultimately tell the Tesla M3 motor to take the watts required to move the car from the Leaf battery?

Thanks again for any information.

Kind regards

All by itself it wont communicate anything. It will depend what interface YOU prepare to join everything together. I think Toms SimpBMS goes a long way towards integration. But there is other stuff out there too, like JBs Chademo/Leaf/SAM32X control VCU unit...

[P.S.Mangelsdorf]

These are very helpful analogies. Let's assume I have a Tesla Model 3 rear motor (yup, I understand that Damien is not yet done with his magic) and a complete Nissan Leaf battery with the BMS, contactors, fuses, etc.

Wouldn't I also need the charger out of the Leaf motor stack?

Then the Leaf battery could be charged either by a level 2 charger (or DC fast charger) designed for the Leaf via the original charging ports?

Is it then correct to say that the Tesla inverter, with an appropriate Damien brain board, would communicate with the battery, hall effect throttle, brakes etc. to ultimately tell the Tesla M3 motor to take the watts required to move the car from the Leaf battery?

I'm not terrible familiar with the Leaf components, so I'm not sure what is required to use each component in a conversion. Typically, OEM components start to be unhappy when they aren't in the original car, hence the replacement boards.

The inverter doesn't necessarily communicate with the battery. The inverter doesn't need to tell the battery anything, the power is just there. The inverter would open or close the contactors, which are large relays to control the HV power. Think of the contactors like a fuel shutoff valve right after the tank, but electrically controlled. In an ideal setup, the BMS will communicate to the inverter, typically telling the inverter to stop if it is pulling too much power from the battery.

There are several charging options, if you are parting out the Leaf yourself you can probably find a way to control that charger (again, I'm not familiar with Leaf stuff) but you can also use a charger from another vehicle if you can get a controller that allows you to configure the charge parameters to match the battery. There are several aftermarket chargers available as well, Thunderstruck seems to have the most ability to change parameters.

[dwmollett]

Thanks to you both for your responses. I think I'm getting a better understanding and as such it may be a good time for me to ask more targeted questions under a different topic. I'm sure everyone here is all aquiver!

[VVektor93]

Can the tesla SDU be mounted backward?

The problem is because:
Mass center of rear SDU is on back-left side, also in some European countries driver is sitting on a left side. So the car mass center is on the left side.

[sfk]

Can the tesla SDU be mounted backward?

Electric motors themselves don't usually care about mounting orientation or direction of rotation. The problems arise when lubrication and cooling systems are in effect. Case in point: the Nissan Leaf motor and housing uses the gears to "fling" lubricant into a reservoir. This only works when the motor is in the original horizontal arrangement and the motor is spinning in the original forward direction.

Using the Leaf motor in a different mounting orientation or direction of rotation may require modifying the cooling and lubrication systems to work. I'm not sure about the Tesla SDU but should be easy to find out.

[P.S.Mangelsdorf]

Can the tesla SDU be mounted backward?

Electric motors themselves don't usually care about mounting orientation or direction of rotation. The problems arise when lubrication and cooling systems are in effect. Case in point: the Nissan Leaf motor and housing uses the gears to "fling" lubricant into a reservoir. This only works when the motor is in the original horizontal arrangement and the motor is spinning in the original forward direction.

Using the Leaf motor in a different mounting orientation or direction of rotation may require modifying the cooling and lubrication systems to work. I'm not sure about the Tesla SDU but should be easy to find out.

The LDU requires a different oil pump, not sure on SDU.

[Toddy]

Can the tesla SDU be mounted backward?

Electric motors themselves don't usually care about mounting orientation or direction of rotation. The problems arise when lubrication and cooling systems are in effect. Case in point: the Nissan Leaf motor and housing uses the gears to "fling" lubricant into a reservoir. This only works when the motor is in the original horizontal arrangement and the motor is spinning in the original forward direction.

Using the Leaf motor in a different mounting orientation or direction of rotation may require modifying the cooling and lubrication systems to work. I'm not sure about the Tesla SDU but should be easy to find out.

The LDU requires a different oil pump, not sure on SDU.

Hi there,

I am also in the process of fitting a (Front) SDU into my '96 VW T4 Multivan. I do this toghether with a mate who did the same (into a T5). He runs the SDU in "backward" direction (and almost upright position) since 30.000km and has not experienced any trouble. Power and max speed are limited of course (to c. 100kw and 140km/h max) I had the question about sufficient lubrication myself (viewtopic.php?f=10&t=1048#p17188) but after some research and discussion it appears to be no problem even to build the SDU fully into upright position. I have posted a photo in the thread. The SDU has a cooling system in place (which I will not use as my conversion is not about speed) and no oil pump to my knowledge.

I intend to use the openinverter drop-in board for SDUs and from the discussion here I take it that the board can handle either roation direction.

Best, Toddy

[P.S.Mangelsdorf]

The SDU has a cooling system in place (which I will not use as my conversion is not about speed)

I would be very wary about running without coolant.

As I understand it the cooling is primarily for the inverter, and I'd expect the electronics would still need to be cooled regardless of speed.

[Isaac96]

Apparently the inverter has very low thermal mass, and will overheat very quickly even at no load without coolant. I hope you at least monitor your temperature.

[Toddy]

Good to know! Thanks for the hint.

As I myself do not have a sense of how hot the inverter can get: do you think a small and simple cooling loop, e.g. with a small watercooler from a motorbike would be required or sufficient. Or would even a bigger one with a cooler fan be necessary?

[SKB123]

yes but they are officially limited to 110kW so not quite for race cars but for normal road use with occasional bursts I'd say they suffice

OK another question, is it a waste to put this motor and battery together ❤
If only 110kw limit for a 211kw motor? Or is current/limiting
Do you mind explaining the limits please as I was thinking of doing this also.