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Discussion Starter #1
Hello,

I'm starting a Factory Five 818 EV conversion! I originally was planning on building the car from scratch and had a deposit in with FFR, but a rolling chassis came up near me for sale about a month ago and I agreed to buy it. The seller is holding it for me for a few months, but hopefully I'll be picking it up shortly. I've attached a photo of the car as it was when I agreed to buy it.

In the meantime I've been getting everything together I'll need for the EV swap. I have a Tesla Model S LDU arriving from 057Tech tomorrow and have axles on order.

But now I sort of hit a brick wall - what else do I need?. I've been reading the forums, but besides batteries and a BMS, I'm a bit stumped on what else I'm going to need to wire everything up. I know I'm going to need to sort out mounting all the hardware, as well as cooling the motor and batteries.

I searched the forums and have read a lot of the wiki posts, but I'm guessing I'll need some other major components as well as things like shunts, cut-off switches, etc. I realize all of this is completely DIY and I need to do all the leg work, but feel like I'm missing some obvious "getting started" guide that everyone else has already read!

Thanks for any pointers, I am looking forward to posting more as I sort this all out!
 

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You gotta watch Damian Maguire's Tesla videos on youtube. His BMW is Legendary!!! Plus he has the Open inverter forum. He builds the logic Board so that it can be reprogrammed for your control.
 

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Hello,

I'm starting a Factory Five 818 EV conversion! I originally was planning on building the car from scratch and had a deposit in with FFR, but a rolling chassis came up near me for sale about a month ago and I agreed to buy it. The seller is holding it for me for a few months, but hopefully I'll be picking it up shortly. I've attached a photo of the car as it was when I agreed to buy it.

In the meantime I've been getting everything together I'll need for the EV swap. I have a Tesla Model S LDU arriving from 057Tech tomorrow and have axles on order.

But now I sort of hit a brick wall - what else do I need?. I've been reading the forums, but besides batteries and a BMS, I'm a bit stumped on what else I'm going to need to wire everything up. I know I'm going to need to sort out mounting all the hardware, as well as cooling the motor and batteries.

I searched the forums and have read a lot of the wiki posts, but I'm guessing I'll need some other major components as well as things like shunts, cut-off switches, etc. I realize all of this is completely DIY and I need to do all the leg work, but feel like I'm missing some obvious "getting started" guide that everyone else has already read!

Thanks for any pointers, I am looking forward to posting more as I sort this all out!
What I see missing from your list is a battery charger, DC-DC converter (to charge a 12V battery), and fuses and contactors (big relay that is how you'll turn on the car).

057 doesn't release manuals unless you buy the unit (at least the last time I checked) so I don't know what you'll need in terms of gauges and control wiring. You'll want to read the manual and instructions they give you about half a dozen times, let it sit for a week or two, and read it again, so that you're very familiar with what it needs, and give yourself time to digest all of the information.

Likely, what you'll need for contactors and fuses will be covered by 057's instructions

The Open Inverter/ EVBMW solution mentioned previously is great (its what I'm going to be using) but since you already have a unit coming from 057 it wouldn't be applicable here.

You'll still need a 12V wiring harness. I believe Ron Francis has some kits for Factory Five's products, and they have some great wiring diagrams. If you take some time with the Ron Francis diagram and the 057 diagram, you should be able to figure out which ICE wiring components you need, which you don't, and which you'll need to make do something else in your car. (example: in my build the alternator connection will go to the DC-DC converter, and the neutral safety switch will be eliminated)


To circle back to the charger, you'll need to decide what type of charging you'll need. Typically on board chargers can handle Type 1 and Type 2 (110V and 220V outlet/charging station) via the J1772 protocol. This means the car's plug sends AC current in, and the charger converts to DC and charges the battery. Some have control for J1772 built in, others you will need to add another box to handle that.

If you want to DC fast charge (Type 3) you'll need something that can communicate with a CHADEMO station (I haven't seen any DIY solutions for CCS). On a Type 3 charger, the charging station does the conversion to DC, and the plug in your car connects directly to the battery (via a set of contactors). The Orion2 BMS can handle CHADEMO and J1772, and the Open Inverter community (read: Damien) is working on an open source CHADEMO setup as well.
 
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Hi, thanks for all the advice, I definitely need to spend more time on YouTube watching other people's builds. I'll check out Damien Maguires!

The motor has arrived, and I was able to pick up the 818 chassis last week. My current project is to pull the fuel tank and motor and start getting the Tesla mounted. Photos are attached, I can't figure out how to embed them in the post.

I didn't find any technical information with the 057 motor, but I didn't have the chassis at the time so I should probably go back and look more closely.

I've started to research batteries, it looks like I'll be able to get the required amount of LG Chem batteries (of the kind EV West sells) to fit in the car, but I'm still looking into other options. The LG Chems would give me 46.8 kW, which seems a bit low. I like the capacity and density of the BMW i3 batteries, but a pack of them will end up being 1000lbs and 85kW which seems too much. I'm hoping to find something that splits the difference - 60kW and 400v would be great.

I would probably be happy with just Type 2 J1772 charging, but having the ability to do Type 3 would be good, so I'll look into that BMS.

Thanks for the advice about the 12v system, I'll look into that as well, and look up Ron Francis. I've also been thinking about how to do pre-charge.

After battery selection the next item on my list is how to handle battery cooling - I haven't found any good resources on how to design or buy chill plates, or how to do water cooling with them, but I've only been chipping away at that a bit.

My basic plan of action is:

1) Mount the motor and drive shaft
2) Battery selection
3) Battery cooling design
4) Battery mount engineering and installation
5) BMS and charging solution
6) 12 volt system and other electronics (pre-charge, instrumentation, etc)
7) brakes and overall finishing the car

Lots of hand-waving right here I know, but I'll keep chipping away at it in that order.
 

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After battery selection the next item on my list is how to handle battery cooling - I haven't found any good resources on how to design or buy chill plates, or how to do water cooling with them, but I've only been chipping away at that a bit.
Cooling will depend heavily on your battery selection. The LG Chem batteries EV west has are from a Chrysler Pacifica. They have a similar capacity and capability as the Chevy Volt batteries. The Pacifica ones are air cooled using a large heat sink I believe, and the Volt ones have liquid cooling built in. For some great battery info check out Kerry Manning's EVEngineering channel.

https://www.youtube.com/channel/UC1haWsGv-HcI10lapf4MBgg
 

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I've started to research batteries, it looks like I'll be able to get the required amount of LG Chem batteries (of the kind EV West sells) to fit in the car, but I'm still looking into other options. The LG Chems would give me 46.8 kW, which seems a bit low. I like the capacity and density of the BMW i3 batteries, but a pack of them will end up being 1000lbs and 85kW which seems too much. I'm hoping to find something that splits the difference - 60kW and 400v would be great.
To reduce confusion, it helps to use standard terminology. These are modules (permanently linked sets of cells), which are joined together to form the complete battery.

Each of your references to "kW" appears to be intended to mean kWh (kilowatt-hours) of energy, not kW (kilowatts) of power. Energy and power are related but very different concepts. If you use the correct unit (kWh in this case) your plans and questions will be much more clear.

The LG Chem modules sold by EV West are for the Chrysler Pacifica Hybrid, and are typical of plug-in hybrid modules: enough of them in series to reach the typical operating voltage of a modern EV or plug-in hybrid (about 360 V nominal) only have 16 kWh of energy capacity. To get three or more times that capacity without using a much higher battery voltage you would need to connect them in parallel. Parallel module connections have problems, and are never done in production EVs. It would make more sense to me to use modules appropriately configured for a EV of the target capacity and voltage, such as those from a Leaf, Bolt, or even the i3. There are at least three EVs in mass production with roughly 60 kWh @ 360/400 V (nominal/peak) batteries - the complete pack from any of them would meet your target.

Why do you think a battery composed of i3 modules would be 1000 lbs and 85 kWh? There are three different i3 battery configurations, strangely advertised by BMW by their amp-hour capacity, and all presumably running the same voltage (96 cell groups in series for 360 V nominal or about 400 V maximum). They are 60 Ah (~21 kWh usable), 94 Ah (~32 kWh usable), and 120 Ah (42.2 kWh usable). A 1000 pound and 85 kWh pack at 400 V (peak, 360 V nominal) would be two complete 120 Ah i3 packs in parallel... yes, that's a lot!
 

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Cooling will depend heavily on your battery selection. The LG Chem batteries EV west has are from a Chrysler Pacifica. They have a similar capacity and capability as the Chevy Volt batteries. The Pacifica ones are air cooled using a large heat sink I believe, and the Volt ones have liquid cooling built in.
The LG Chem modules in the Pacifica sit on a liquid-cooled chill plate, which is the thermal management design used by most current EVs. Tesla's internal coolant piping and the Leaf's lack of any active cooling are the notable exceptions. Plug-in hybrids are similar, with the Volt's liquid cooling fins between the cells and the Mitsubishi Outlander PHEV's air cooling being the notable exceptions.
 

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After battery selection the next item on my list is how to handle battery cooling - I haven't found any good resources on how to design or buy chill plates, or how to do water cooling with them...
If you group the modules the same way the original vehicle does (apparently two groups of three of those LG Chem modules in the Pacifica) you could use the chill plates and even the mounting brackets from that vehicle.

For an example of someone who has had custom chill plates built (for those LG Chem modules), see snowdog's Electric Supercar build thread... although all of the information is buried in YouTube videos.

Also keep in mind that if you want to use the vehicle in cold weather, you will want to use the thermal management system to heat the battery, not just to cool it.
 

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Discussion Starter #9
To reduce confusion, it helps to use standard terminology. These are modules (permanently linked sets of cells), which are joined together to form the complete battery.

Each of your references to "kW" appears to be intended to mean kWh (kilowatt-hours) of energy, not kW (kilowatts) of power. Energy and power are related but very different concepts. If you use the correct unit (kWh in this case) your plans and questions will be much more clear.
Ah yes, I knew this, I was being sloppy. Thanks for the reminder. I should know better, we have a Tesla M3 and a Pacifica Hybrid.

The LG Chem modules sold by EV West are for the Chrysler Pacifica Hybrid, and are typical of plug-in hybrid modules: enough of them in series to reach the typical operating voltage of a modern EV or plug-in hybrid (about 360 V nominal) only have 16 kWh of energy capacity. To get three or more times that capacity without using a much higher battery voltage you would need to connect them in parallel. Parallel module connections have problems, and are never done in production EVs.
This is interesting to me - I spoke with someone at EV West and that's exactly what they suggested doing - 3 sets of 6 modules wires together in parallel, for 360 volts nominal and 46.8kWh. I hadn't thought of the complexity of wiring them in parallel though, but it makes sense. Also given the available space I was thinking of physically arranging them in possibly uneven sets, so that would complicate things as well.

It would make more sense to me to use modules appropriately configured for a EV of the target capacity and voltage, such as those from a Leaf, Bolt, or even the i3. There are at least three EVs in mass production with roughly 60 kWh @ 360/400 V (nominal/peak) batteries - the complete pack from any of them would meet your target.
Why do you think a battery composed of i3 modules would be 1000 lbs and 85 kWh? There are three different i3 battery configurations, strangely advertised by BMW by their amp-hour capacity, and all presumably running the same nominal voltage. They are 60 Ah (~21 kWh usable), 94 Ah (~32 kWh usable), and 120 Ah (42.2 kWh usable). A 1000 pound and 85 kWh pack at 400 V (peak, 360 V nominal) would be two complete 120 Ah i3 packs in parallel... yes, that's a lot!
I was looking at these batteries (https://www.ebay.com/itm/5-3kWh-BMW-i3-battery-module-45V-120Ah/123919535208). If I read the specs correctly, I would need 8 to reach a nominal voltage of 364volts with a 42.4 kWh capacity. I had doubled that because I felt like 42.2 kWh was too low, but looking at it again thats just a touch under the capacity of 18 LG Chems and about 200lbs lighter, so maybe a better option.

To your point, sounds like one complete pack from an i3 might be enough. I am hoping this car will have enough range to do some track laps (I know the problems with the Model S motor), so I was hoping for something more in the range of 60 kWh, but this may be a good start.

I would like to liquid cool the batteries, but I haven't found a good source for chill plates. Do they need to be custom made?
 

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I would probably be happy with just Type 2 J1772 charging, but having the ability to do Type 3 would be good, so I'll look into that BMS.
240 volt AC charging is called Level 2 (rather than "Type 2"), and while some people call fast DC charging "Level 3", it's not... it's just fast DC charging. Fast DC charging is a challenge for DIY builds, and which standard you want to work with (CHAdeMO as used by most Japanese manufacturers, or CCS as used by almost everyone else) is important to the components that you need and ability to make the system work.
 

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Discussion Starter #11 (Edited)
240 volt AC charging is called Level 2 (rather than "Type 2"), and while some people call fast DC charging "Level 3", it's not... it's just fast DC charging. Fast DC charging is a challenge for DIY builds, and which standard you want to work with (CHAdeMO as used by most Japanese manufacturers, or CCS as used by almost everyone else) is important to the components that you need and ability to make the system work.
Again, I knew that, sorry. We have a Level 2 charger here at home. I will probably be fine sticking with Level 2 for now though I was hoping to be able to do quick charge someday. For now its a ways off anyway.

brian_ said:
If you group the modules the same way the original vehicle does (apparently two groups of three of those LG Chem modules in the Pacifica) you could use the chill plates and even the mounting brackets from that vehicle.
I think that might be a challenge given the space constraints on this chassis, but its something to consider. If the i3 pack can be split and used in pieces, that might work.

Seems like it might be tricky to source one of the newer 42 kWh i3 packs.
 

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This is interesting to me - I spoke with someone at EV West and that's exactly what they suggested doing - 3 sets of 6 modules wires together in parallel, for 360 volts nominal and 46.8kWh. I hadn't thought of the complexity of wiring them in parallel though, but it makes sense. Also given the available space I was thinking of physically arranging them in possibly uneven sets, so that would complicate things as well.
The complexity is not so much in the high-voltage wiring but in the BMS... ideally you would use three complete BMS systems for that, and have contactors for each of the three strings. I'm sure that EV West would be happy to sell you all of that hardware. ;)

I was looking at these batteries (https://www.ebay.com/itm/5-3kWh-BMW-i3-battery-module-45V-120Ah/123919535208). If I read the specs correctly, I would need 8 to reach a nominal voltage of 364volts with a 42.4 kWh capacity.
Those are the 120 Ah i3 modules, and yes, eight is a full battery pack for the i3.

I would like to liquid cool the batteries, but I haven't found a good source for chill plates. Do they need to be custom made?
I've never heard of a source of ready-to-use off-the-shelf chill plates, and I wouldn't expect to because there are so many possible modules and so many possible configurations. I think that one reason that there is so little experience with buying or building chill plates in this forum is that most people using liquid-cooled modules have used Tesla and Chevrolet Volt modules, which have the liquid cooling components built in. One successful project used Chevrolet Bolt modules (which require a chill plate), but in that case the entire battery pack was used intact, complete with cooling system.

The Volt is being discontinued, the Tesla Model S and X are nearly the end of their lives, and the Tesla Model 3 modules are very awkwardly sized to used in a conversion, so over the next few years I think we'll see a lot of builders forced to sort out this chill plate issue to use liquid-cooled modules salvaged from (or intended for) newer EVs.
 

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I think that might be a challenge given the space constraints on this chassis, but its something to consider. If the i3 pack can be split and used in pieces, that might work.
The eight modules can certainly be placed in some different arrangement, but I haven't seen enough detail to guess at how the chill plates might be designed.

Seems like it might be tricky to source one of the newer 42 kWh i3 packs.
The i3 was always a little obscure - at least in Canada - and the 42 kWh pack is relatively new... so yes, supply seems likely to be an issue.
 

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Chill plates

You are not moving a huge amount of energy from the batteries - the main loads appear to be when doing fast DC charging - even on the track the amount of energy to be shifted is not that large

The basic idea for a simple DIY chill plate would be a thick aluminium plate with liquid flowing through it - through drilled holes or through a gap between two plates

It's main function - and the reason the Leafs have battery degradation issues - is not so much cooling/heating as temperature equalisation
 

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The i3 was always a little obscure - at least in Canada - and the 42 kWh pack is relatively new... so yes, supply seems likely to be an issue.
Seems like sourcing any battery modules in the 40-60 kWh range in a usable form factor is a bit tricky. I don't see any i3 or Chevy Bolt batteries available, so the best options right now seem to be a pair of Volt packs or 18 LG Chem modules.
 

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Seems like sourcing any battery modules in the 40-60 kWh range in a usable form factor is a bit tricky.
True, compared to conventional vehicles any EV is rare, so parts are not plentiful.

I don't see any i3 or Chevy Bolt batteries available, so the best options right now seem to be a pair of Volt packs or 18 LG Chem modules.
You can probably buy a complete Bolt battery (from an authorized GM dealer, with online discount... part number 24285978 or 24289549) for about the same cost as buying 18 of those LG Chem modules from EV West 18 @ US$735 each).
 

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Yeah, it looks like an entire Bolt battery is a little over $12k, and 18 LG Chems would be $13k.

Bigbattery.com has the LG Chems a lot cheaper, but I'd still have the BMS issue: https://bigbattery.com/product/60v-lg-chem-battery-module/

Its not clear to me I can pull a lot of power (in terms of max amps) out of the Bolt batteries. I do like that the packs should be new and reasonably available for a while. I wonder what happens if you try and order one without owning a Bolt.
 

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The cheapest way of procuring batteries is to pull the complete pack out of an OEM wreck. You'll also get things like contactors, fuses, and wiring, which is nice...You might also be able to reuse other stuff, but it often involves hacking the CAN bus, and that scene is still pretty green.

Track time seems Hard. Even the Model S conks out after a lap or two, right?
 

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Track time seems Hard. Even the Model S cocks out after a lap or two, right?
Yeah, it seems to be the motor, which doesn't dissipate heat well. The Model 3 and next-gen S can handle the track better, but the DIY scene hasn't cracked those motors yet.
 
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