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I have been looking for a project car (roller) to convert to an EV for a few months. I came across this car that had already been converted and was priced reasonably. I was told that the previous owner had let it sit and batteries were dead. It was powered by 40 CALB batteries and has a Warp11 motor. The photos below should give an idea of the rest of the system.

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I am looking at purchasing these for power:


My question is if this looks reasonable. I should end up taking less space with the newer batteries as well I think so will need to rebuild the cages for the batteries.

Also, I would like to "clean up" the cabling mess where the controller and charger are as well as put in a charger that would allow for fast charging. What would your recommendations be for this?

Thank you in advance for your time and consideration.

Arthur
 

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Have you thought about used OEM batteries? $3-4k gets you a full Leaf pack. 24kW in 48 easily-repurposed modules of 7.5V.
 

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Have you thought about used OEM batteries? $3-4k gets you a full Leaf pack. 24kW in 48 easily-repurposed modules of 7.5V.
Was I wrong in my calculations? I thought that the purchase above would give me 28kW right? I will look into OEM. How easy are they to reconfigure for space though?
 

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Hi,
I converted a 2000 Boxster S and was able to fit 32KWh of Chrysler Pacifica batteries (12 modules) into the engine bay alone. The battery cost was only $4500.

BMS cost is usually the biggest concern with OEM batteries; some cells (BMW hybrid, Volt) have reusable OEM BMS systems which should work well.

BMW hybrid packs are an excellent solution - 740e packs are ideal, and are often available for very good prices. 9KWh per pack, and easily reconfigured into a 32s3p system (120v 75Ah), or more can be paralleled for more capacity. And the BMS can be controlled and monitored by the SimpBMS system.
OpenInverter discussion

-Isaac

EDIT I'm also working for someone else and installing 72s of CA100 LiFe cells into his Boxster -- not my first choice but definitely possible, results in 230v nominal.
 

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You are maybe the first person I've heard of who bought someone else's DIY EV.

Good for you, you'll save a ton of time and effort.

There is really no world where buying CALB cells makes sense anymore. OEM EV is the way to go. Everyone who's used CALBs has had at least one issue, anyone who's used OEM EVs has not. It's almost complete opposite ends of the spectrum in terms of quality. Cost is better too.
 

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Discussion Starter #6
Recommendations for OEM? The car originally had 40 batteries, 20 batteries in the front and 20 hanging under in back. the wiring is set for that right now. If you want to send links to what you would recommend I would appreciate it.
 

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There is really no world where buying CALB cells makes sense anymore. OEM EV is the way to go. Everyone who's used CALBs has had at least one issue, anyone who's used OEM EVs has not. It's almost complete opposite ends of the spectrum in terms of quality. Cost is better too.
Agreed. OEM cells are worlds better especially in terms of power density and cost. The reliability is also amazing -- any batteries that find their way to the second hand market have already been tested in vehicles. Configurability is the only remaining issue, since usually OEM packs have at least 10 cells per module.

@wasexton -- DC fast charging is separate from regular AC charging. High power AC chargers are available (Elcon PFC5000, Valeo 6.6Kw). And these can also be paralleled to double or triple the power.
Fast charging, however (the use of CHAdeMO or CCS) is well nigh impossible at lower voltages, and is difficult to implement anyways. DIY fast charging is still on the bleeding edge.


I would also suggest moving the Zilla (though maybe not the Hairball) into the engine bay. It should fit well above the motor, which would shorten the cabling and reduce messiness.

You can put the charger into the gas tank, assuming it's waterproof. My conversion has a TSM2500 sitting in the bottom of the gas tank on top of a big hole, and the J1772 charging inlet is in the gas cap. Thus 120/240VAC has the shortest possible run.

-Isaac
 

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This was a center engine car so the motor is under the car. :) The controller will be about the same length from the motor if it is mounted front or back. I will put it up on jackstands tomorrow and take a few photos.
 

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This was a center engine car so the motor is under the car. :) The controller will be about the same length from the motor if it is mounted front or back. I will put it up on jackstands tomorrow and take a few photos.
Yup I know exactly what you mean ( just finished my 2000 Boxster conversion last week :) )
I mean putting the controller right on top of the motor. Also maybe consider some batteries on either side of the motor -- there is a lot of good space there, and it's ideal for weight distribution -- maybe you can free up the frunk and/or the trunk!

-Isaac

EDIT Didn't see your battery post... Pacifica or Bolt modules are great for energy density.
Thunderstruck Motors is the only source I know of for Bolt modules, which are 37v and 180Ah apiece. Thunderstruck batteries Their prices are fair to great.
 

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I will look at that! I have some rearranging to do anyway but I do like the "cage" that was under the back to hold batteries before. It was hanging a bit low but with lower profile batteries I could use the same mounts and just rebuild the cage. That would balance well with weight in the front. Looking for OEM batteries now (ebay) so would appreciate any suggestions and recommendations on configurations. Since cables are in place I will probably leave them in the same locations but just with them taking less space (half front and half back).
 

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Yup I know exactly what you mean ( just finished my 2000 Boxster conversion last week :) )
I mean putting the controller right on top of the motor. Also maybe consider some batteries on either side of the motor -- there is a lot of good space there, and it's ideal for weight distribution -- maybe you can free up the frunk and/or the trunk!

-Isaac

EDIT Didn't see your battery post... Pacifica or Bolt modules are great for energy density.
Thunderstruck Motors is the only source I know of for Bolt modules, which are 37v and 180Ah apiece. Thunderstruck batteries Their prices are fair to great.
I will look at that! I have some rearranging to do anyway but I do like the "cage" that was under the back to hold batteries before. It was hanging a bit low but with lower profile batteries I could use the same mounts and just rebuild the cage. That would balance well with weight in the front. Looking for OEM batteries now (ebay) so would appreciate any suggestions and recommendations on configurations. Since cables are in place I will probably leave them in the same locations but just with them taking less space (half front and half back).
Controller should be left where it can have no water intrusion. Keeping it where you have it is not going to be a big deal. If the controller is water proof then it does not matter if you put it on top of the motor. If you do put it on top of the motor be sure you isolate the controller so it can't get wet. Im dealing with a controller that has some serious corrosion issues and it looks like it was wet for a long time and maybe even sat in water. Don't let that nice controller be destroyed by corrosion.
 

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Controller should be left where it can have no water intrusion. Keeping it where you have it is not going to be a big deal. If the controller is water proof then it does not matter if you put it on top of the motor. If you do put it on top of the motor be sure you isolate the controller so it can't get wet. Im dealing with a controller that has some serious corrosion issues and it looks like it was wet for a long time and maybe even sat in water. Don't let that nice controller be destroyed by corrosion.
Right, my apologies for the misleading advice. Zilla manual says to avoid water spray altogether!!!

-Isaac
 

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Discussion Starter #13
Right, my apologies for the misleading advice. Zilla manual says to avoid water spray altogether!!!

-Isaac
No problem. One less thing to change. :) I think I am just going to focus on batteries for now. If you see anything on the market you would recommend I would appreciate a link.
 

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What would you think of 8 of these as OEM that have BMS?


As a FNG doing this, if I get something like these OEM, where do I get the connectors that could be used to join 4 of these in the front of the car to the existing 2 cables that route to the controller in the back? Terminal lugs? I would need to do the same in the back. 4 under the car.
 

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DO NOT get Leaf batteries from TechDirectClub. I got a set of 48 about 2 years ago and they only gave half capacity (30Ah instead of 66Ah).

You would need 2/0 lugs (or larger) to carry enough power.
EVWest link
Amazon link

Also you need a BMS which watches all the cells at once, not 1 BMS per 7 modules (unless you can make them communicate -- I have done this, not recommended. It's a huge pain).
Orion BMS is good, a bit expensive.
Thunderstruck BMS is a little cheaper, and easier to deal with separate front and rear packs.

Battery recommendations -- what capacity do you want, and what voltage?
Assuming 120V, think about some Pacifica modules, they are 60 volts apiece and 45 Ah. So you'd probably want to use 2 or 3 in series and 4 or so in parallel to get good range. (2 series, 4 parallel is 22Kwh, about 55-60 highway miles).

Bolt modules are also a good option, Thunderstruck again has a good deal (they got a special shipment of them from the factory). Bolt batteries
These are 36V and 180Ah, so maybe 4 in series for 144V and no paralleling. That would get you 25Kwh, so about 65-70 miles of range tops.

-Isaac

(note -- range estimates are very quick and dirty, test before suing anyone please).
 

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Thank you! That was information I was looking for. I will look at the batteries from Thunderstruck. I think I may be able to get 6 in the space judging by the dimensions listed.

What about this for BMS for each pack?


Any experience with these?
 

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I have seen a couple of reviews on these and seem to be good as well

 

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Those do look like good products. However, they are missing a crucial feature for EV use:
Individual cell monitoring and error outputs.

The primary job of a BMS in a car is not to balance the cells, though it can be used to do that. What is most important is constant monitoring of each cell's voltage, and reporting that voltage to where it can be read by the driver -- or shut off the charger or motor. For example, my BMS activates a buzzer when the voltage gets too low, alerting me to lay off the throttle and find a place to charge.
It also communicates with my charger to prevent overcharging.

So a AliBaba BMS of the E-bike variety is not quite good enough. Those systems protect batteries by disconnecting power once voltage gets too low or too high and by limiting discharge current.
But that requires the BMS to carry all the output power through MOSFETs, which must be able to carry all the power in and out of the battery. They will detonate when used at EV power levels.

If you could make the AliBaba BMS units communicate together and display voltage somewhere, they would be usable.
My car uses these BMS units: Smart Bluetooth BMS -- but ONLY because I was able to make them talk together and talk to my charger, because the BMS protocol is available.

If you can find the communication protocol for one of those units, I may be able help you with some code to tie them all together and make them suitable for EV use.
 

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Discussion Starter #19
The one you linked to would be fine as well. How would these be wired to the Bolt packs mentioned above?
 

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Discussion Starter #20
Ordered batteries from thunderStruck. 4 of these packs. Waiting for them to come in


 
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