Batteries for Tesla motor in 1965 VW Karmann Ghia

1510 Views 17 Replies 7 Participants Last post by dlaroche1, 1 mo ago

TheRealAI

Discussion Starter · 2 mo ago

Hello,

I have a Tesla motor mounted in a 1965 VW Karmann Ghia. I am finally at the point where I am ready to design the battery pack(s) and BMS. I had assumed I could use 14 of the LG JH3 battery packs that EV West offers, but they are saying that I need at least 26 of them to support the Tesla. That is about 42kWH and seems like complete overkill (and insanely expensive for a fun project car!).

I may decide to upgrade the battery pack in the future, but I don't plan to need more than 50 miles of range per day in the foreseeable future.

While I've had positive experiences with EV West, I've been a lurker enough on this site to know that some people have had bad experiences with them and that they can be expensive.

Can anyone weigh in on the LG JH3 as an option? I've read the other articles on here, so I am only looking for any new information that has not been shared previously, which may be a positive counterpoint to the concerns re: the design that I have read.

Do I really need 26 JH3s to support the current requirements for the Tesla motor in such a tiny car? Could I use only 14?

What else should I consider for batteries to power a Tesla motor? I've looked through the forums a few times and haven't seen anything that is a clear-cut and recent battery recommendation for a Tesla motor on such a small and light car, so I apologize if I am asking a question where there is an obvious answer on the site that I missed.

Thanks!

1 - 18 of 18 Posts

remy_martian

· #2 · 2 mo ago

"Tesla motor"??

I assume you mean drive unit.

Which one?

What kind of continuous and peak power are you specifying?

Range expectation?

You can use Dewalt drill batteries to run that motor, so you need to provide a lot more info than you have.

TheRealAI

Discussion Starter · #3 · 2 mo ago (Edited)

Hi, Remy-

It's the Tesla small rear drive unit (I think it came from a mid-2010s Model S). I purchased it from EV West about a year and a half ago. I think the stated continuous and peak for the motor are 35kW and 220 kW, respectively. Although 220kW in a tiny KG (original engine created about 40hp) would be very unwise, so I don't think that will ever be reached.

For range, I am fine with 50-ish miles per day(charge). I would like to be able to increase the range in the future, if that matters.

Thank you very much.

remy_martian

· #4 · 2 mo ago

From what I can tell, that's a rescued residential storage battery.

It has no provisions that let you easily cool it or warm it for a vehicle application, so you're stuck at a low C-rate. That's probably why EVW wants you to run two strings in parallel.

Sounds like your nose is buried in your calculator and not in the applicability of the module.

I'd move on, but others may have a more positive outlook.

Reactions: 1

TheRealAI

Discussion Starter · #5 · 2 mo ago

Thank you for weighing in, Remy.

I think I am leaning toward other options. The cooling/ heating challenges you referenced (and no easy way to apply a chill plate to the case), combined with the cost seem a bit rough for a "fun" project car.

Is there another battery pack alternative that you would recommend? For example, the leaf, volt, or Pacifica modules? Or maybe the 60.8V/ 2.6 kWH LG (which I think is the same as the Pacficia and can accommodate a chill plate for active cooling)?

Any opinions/recommendations are appreciated. I used to be an aircraft electrician, but I am a bit out of practice, and everything I worked with in that world was lead acid.

Thanks again.

remy_martian

· #6 · 1 mo ago

It's a small car and I've not faced that tight of a packaging constraint, so others will need to weigh in on alternatives. You could redo a Bolt or Mach-E module to 2P maybe?

Reactions: 1

joekitch

· #7 · 1 mo ago

Re-soldering a mach-E module is doable but two problems
for one, it's pretty annoying to do, cracking open each module then cutting and re-soldering internally, for however many modules you want
this vid goes into some depth

for two, you probably wont even use that many modules, mach e packs are BIG

some upsides:
the price per kwh on them is really good, like $112 in the best case

Rectangle Font Pattern Horizon Cumulus

they're extremely new, less concerns about goofy modules
whatever modules you don't use can be kept aside to make a fantastic diy powerwall

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remy_martian

· #8 · 1 mo ago

They aren't "resoldered". The reconnection is mechanical.

joekitch

· #9 · 1 mo ago

oh dang, i saw the connections in a short and thought the riven gun was a spot welder
still, kind of a pain to do

remy_martian

· #10 · 1 mo ago

Spot welder or laser is the way to do it. Solder, never.

brian_

· #11 · 1 mo ago

TheRealAI said:
Or maybe the 60.8V/ 2.6 kWH LG (which I think is the same as the Pacficia and can accommodate a chill plate for active cooling)?

Yes, LG sold these modules, intended for the Chrysler Pacifica PHEV, as new product through some distributor(s) who sold them for aftermarket use. That wasn't the intent, so LG shut down the supply and there are now few if any available... but anyone who got them basically had new Pacifica modules, without going through Chrysler. EV West turned to their current LG JH3 modules as a replacement, but those modules are designed and built for stationary energy storage systems with low power requirements.

Reactions: 1

brian_

· #12 · 1 mo ago

TheRealAI said:
I have a Tesla motor mounted in a 1965 VW Karmann Ghia. I am finally at the point where I am ready to design the battery pack(s) and BMS. I had assumed I could use 14 of the LG JH3 battery packs that EV West offers, but they are saying that I need at least 26 of them to support the Tesla. That is about 42kWH and seems like complete overkill (and insanely expensive for a fun project car!).

...

Do I really need 26 JH3s to support the current requirements for the Tesla motor in such a tiny car? Could I use only 14?

The EV West recommendation is based on what they think is an acceptable discharge rate for the battery modules, and an assumption of the power that will be used by the Tesla drive unit. If you limit the drive unit to lower power, you can safely use less battery. But EV West's idea of acceptable discharge rate is probably as optimistic as one might expect of a company selling something and not providing any warranty.

Reactions: 2

MylesT

· #13 · 1 mo ago

Pre-lithium, common advice on batteries to EV DIYers was to buy used batteries because guaranteed "you will kill your first set of batteries" --- and most did---many, just due to buying new and letting them sit for months/years. These days, with lithium, this is not the primary worry. Still, going with good used batteries can offer a great get-your-feet-wet experience at a fraction of the cost of new batteries. This especially if you're not planning on a daily driver car. I mean, you can pick up entire packs of used batteries for a song in some cases. I'll be pulling modules from another used 23kwh lithium-ion pack in the next few days that will end up powering this ol' boy: www.evalbum.com/348 . These batteries have already seen 80kmiles (~1k full charge cycles), but they are likely still super-low resistance, low self-discharge, near zero maintenance, lighter than the PbA alternative and will probably still have 2-4x the charge cycle life of a new set of PbA batteries and at less cost. And for my application (definitely NOT a daily driver), with maybe 1000 miles per year usage, there will only be 14-20 charge cycles annually. Anyway, sorry for the pitch...if money is no object, please ignore.

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Reactions: 1

dlaroche1

· #14 · 1 mo ago

TheRealAI said:
Hello,

I have a Tesla motor mounted in a 1965 VW Karmann Ghia. I am finally at the point where I am ready to design the battery pack(s) and BMS. I had assumed I could use 14 of the LG JH3 battery packs that EV West offers, but they are saying that I need at least 26 of them to support the Tesla. That is about 42kWH and seems like complete overkill (and insanely expensive for a fun project car!).

I may decide to upgrade the battery pack in the future, but I don't plan to need more than 50 miles of range per day in the foreseeable future.

While I've had positive experiences with EV West, I've been a lurker enough on this site to know that some people have had bad experiences with them and that they can be expensive.

Can anyone weigh in on the LG JH3 as an option? I've read the other articles on here, so I am only looking for any new information that has not been shared previously, which may be a positive counterpoint to the concerns re: the design that I have read.

Do I really need 26 JH3s to support the current requirements for the Tesla motor in such a tiny car? Could I use only 14?

What else should I consider for batteries to power a Tesla motor? I've looked through the forums a few times and haven't seen anything that is a clear-cut and recent battery recommendation for a Tesla motor on such a small and light car, so I apologize if I am asking a question where there is an obvious answer on the site that I missed.

Thanks!

I’m running two packs of six Pacifica batteries in my Tesla swapped beetle. You could run six and get close to your 50 miles. I have not needed any heating and r cooling for the batteries.

remy_martian

· #15 · 1 mo ago

"I have not needed any heating and [o]r cooling for the batteries."

Where do you live?

What makes you conclude you don't need it?

dlaroche1

· #16 · 1 mo ago

remy_martian said:
"I have not needed any heating and [o]r cooling for the batteries."

Where do you live?

What makes you conclude you don't need it?

Charleston sc. even at the drag strip I’ve never even found them to be warm. I only charge at 4kw also.

Reactions: 2

DR Tinmax

· #17 · 1 mo ago

TheRealAI said:
Hello,

I have a Tesla motor mounted in a 1965 VW Karmann Ghia. I am finally at the point where I am ready to design the battery pack(s) and BMS. I had assumed I could use 14 of the LG JH3 battery packs that EV West offers, but they are saying that I need at least 26 of them to support the Tesla. That is about 42kWH and seems like complete overkill (and insanely expensive for a fun project car!).

I may decide to upgrade the battery pack in the future, but I don't plan to need more than 50 miles of range per day in the foreseeable future.

While I've had positive experiences with EV West, I've been a lurker enough on this site to know that some people have had bad experiences with them and that they can be expensive.

Can anyone weigh in on the LG JH3 as an option? I've read the other articles on here, so I am only looking for any new information that has not been shared previously, which may be a positive counterpoint to the concerns re: the design that I have read.

Do I really need 26 JH3s to support the current requirements for the Tesla motor in such a tiny car? Could I use only 14?

What else should I consider for batteries to power a Tesla motor? I've looked through the forums a few times and haven't seen anything that is a clear-cut and recent battery recommendation for a Tesla motor on such a small and light car, so I apologize if I am asking a question where there is an obvious answer on the site that I missed.

Thanks!

Hello
I converted a 1972 ghia to electric. Basically I replaced the engine with an AC drive motor and used 5 tesla packs mounted on edge behind the back seat. No cooling of batteries are needed. I get a range of approx 120 miles. 0-60 in 10 sec and top speed of 90+mph. Great setup for a daily driver.
Be happy to share details if interested.

dlaroche1

· #18 · 1 mo ago

I have 12 of the 63v lg batteries from Chrysler Pacifica in my Tesla beetle. 100 mile range and plenty of amps for my performance large drive unit. Technically you only need 6 but I think amps would be greatly lacking.

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