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Discussion Starter · #1 ·
I'm here because we'll. I drive a truck and gas prices are costing me 100$ a week to and from work primarily. I got a mini Cooper with a blown engine and I'm trying to go electric. My only prior experience would be making electric scooters, although that was fairly easy due to the plug and play nature of it. Im working on turning my side by side electric as well. I'd like to drive it around without bugging my neighbors with fart exhaust sounds while driving through the neighborhood. I've been on this forum to read for almost 3 months now but today is the day I decided to actually join and partake. I'm looking forward to being a part of the community and while my knowledge is extremely limited, if I can help, I will. Thanks for having me!
 

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Just a friendly heads-up; converting a car to save money is going to be really tough. If you want to save money on gas, buy a used EV. If you want a big, expensive, and exciting car project to fill up your garage for the next couple years, convert to electric :)

If you want a ballpark number for conversion costs: figure 1 kwh of battery will get you about 3 to 4 miles in a small car. Each kwh will cost you 150 to 300 dollars. So 100 miles of range at a minimum will run you $3750, and likely that is under-estimating.

On top of that, budget 2 to 10k for the motor and adapter, a few thousand more for the charger, BMS, wiring, contactors, battery boxes, misc fabrication supplies and you are looking at a project that will easily top 10k and more likely run to 15 or 20.
 

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Discussion Starter · #5 ·
Just a friendly heads-up; converting a car to save money is going to be really tough. If you want to save money on gas, buy a used EV. If you want a big, expensive, and exciting car project to fill up your garage for the next couple years, convert to electric :)

If you want a ballpark number for conversion costs: figure 1 kwh of battery will get you about 3 to 4 miles in a small car. Each kwh will cost you 150 to 300 dollars. So 100 miles of range at a minimum will run you $3750, and likely that is under-estimating.

On top of that, budget 2 to 10k for the motor and adapter, a few thousand more for the charger, BMS, wiring, contactors, battery boxes, misc fabrication supplies and you are looking at a project that will easily top 10k and more likely run to 15 or 20.
I have already obtained a warp 9 motor from someone here on the forums. It came with a car that has an adapter plate already mounted up and was actually previously running on the warp 9. It also has a battery box installed but those were made to fit lead acid batteries. I'm going to be pivoting to that as my first ev project. That's a lot of the hard work done. As for saving money, well....It seems I have to hemorage is first haha.
I already have batteries from a previous gig involving electric scooters. I'm just unsure yet as to whether or not I can use them. I'm worried that they can't output enough amps to fulfill the needs of the warp 9. I still have to pickup a controller but for right now I'm letting my wallet rest.
If you have any further advice to offer, I would absolutely love to hear it! I would first like to figure out the feasibility of the batteries before I move further on this. They're 48v at 700wh. I have no clue about amperage output though. I have at least 10 of them to throw into the car for now.
 

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Discussion Starter · #7 ·
14Ah 😬

Call it 50 amps for 20 minutes per battery.

500A @48V if you do 1s10p.
Are you saying I could pull 500 amps per battery? I'm not sure how they're laid out internally. They're weather proofed and I haven't cracked one open because of that.
Some do indeed list 14amp hours and I have others that are listed as 19.2ah.
If I could pull that much amperage from one battery pack, that would be insane! I do understand my battery life would suffer but I figure that would allow for some pretty crazy 0-60 times right?
I'm not looking for 0-60, I'm looking for "fuel economy" however it's nice to know I can get up and GO.
I'm Very intrigued and slightly overwhelmed by the absolute wealth of information that is available.
 

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No. I did not say that. Reread what I wrote.

You get 500amps for 20 minutes at 48V, in theory. For all ten modules hooked up as I said.

I wouldn't be getting a stiffy over performance...it's only about 32HP. My tractor has more power than that. So, you'll have the quickest golf cart in town...or pull a 2 furrow plow 😂
 

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No. I did not say that. Reread what I wrote.

You get 500amps for 20 minutes at 48V, in theory. For all ten modules hooked up as I said.

I wouldn't be getting a stiffy over performance...it's only about 32HP. My tractor has more power than that. So, you'll have the quickest golf cart in town...or pull a 2 furrow plow 😂
I see I see. I didn't know you were multiplying the ten batteries together.
I reread it multiple times and was still confused which is why I asked.
Speed is reliant on gearing. Would I not be trading the torque for speed? I can't say that I understand how the warp 9 is NOT plenty sufficient for road use. People are pulling insane speeds with this motor.
As I stated, I'm looking to make something to top out at 65mph and have decent range (80 miles or so).

I gotta ask, what the heck is your tractor running? Lol
 

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1s10p is short-hand for how the modules are wired. The "s" is series, and "p" for parallel. With 10 modules, you could put them all in parallel for 48v and 140ah, or all in series for 480v and 14ah - plus all the other configurations in between. I am going to guess that they have a BMS, and that they are probably not meant to be put in series - which would be a problem, as 48v is too low to achieve anything but scooter speeds.

7kwh is just not enough battery for a car. Even a very light one at modest speeds, you should figure 250wh/mile at least. So you would be looking at 28 miles of range. A battery can also only give so much power - research "C-rate" to get a basic understanding. For 80 miles of range, I would think you would need 20kwh at a minimum. A pack that size should also have no problem supplying the power you would need to maintain a reasonable speed.

Speed is reliant on gearing.
Yes, but your gearing is fixed by whatever the transmission and final reduction gear is in the car. If at 2000rpms you could select from a range of speeds between say 15 and 55mph, then at 200 rpms your car would only go 1.5 to 5.5 mph. Hence the joke about pulling a plow, as you would indeed have plenty of torque for field work. At 48v you will simply not be able to spin the motor fast enough to get a reasonable speed with the stock transmission.
 

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speed x torque = horsepower (I left out the constant to not confuse you and to give Brian something to nitpick 😂).

If your transmission turns one up by 3x (like torque) the speed gets turned down 3x.

In your case speed x torque (times that pesky constant) = 32HP

Crank the torque up 10x, speed goes down 10x -> tractor
 
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