Gem car lithium batteries?

So what is the maximum range you can achieve with lithium batteries in a gem electric car? What batteries have a good amount of power for a reasonable price and some sort of explanation of how to wire it up with a bms and charge controller and whatever available? I never dealt with something like this is far as scale, just messing with an electric scooter and computers and stuff. Would it also be possible to swap the brushed motor for a brushless one to get some more speed and range?

I use about 200wh per mile.
100 mile range is doable.
Use the search tool to find examples of pmac and induction motor swaps and kits.
A reasonable cost for a high performance new battery with 30 mile + range is about $3k.
Build your own for 1/2, but be aware of a long learning curve.

What’s the most powerful kind of motor available? And what kind of battery would give me 100 miles or more driving aggressively? How do I look up the specs for the original batteries and compare it to lithium batteries? Which cells work the best? What bms/charge controller will work the best with them? What would you recommend so I can just Google that thing?

Is there a particular model or type of electric motor that fits? Or Is there a particular like number of splines on the connector and particular bolt pattern or something I can Google? I figure I would have to go from there. Get the motor, a controller for the motor, batteries for the controller and bms for the batteries. Then figure out how I’m gonna make it fit.

At 200wh per mile, only valid with good efficiency, a 20kwh battery like a Tesla3 module will do it.
However it’s a tough fit mechanically. @MikeKC
I have 80 volt 7.6kw battery modules that fit most classic Gems.
Start with one for mileage test and add one or two later if needed. One is enough for most users.
$2500 each. Includes bms.

Google your batteries. I find a two to one advantage with lithium.

Lots of opinions on that. If you need to ask, best to have help with the first one.
I have a J1772 charger that will add >10 miles per hour range.

Standard 19 spline motor if there is space for larger motor. I have 8kw cont 35 p-hp motors that will do what you need.
A kit with controller, harness, and support. $1700.

Do the measuring first. IMO. A forum search will show tested solutions.

Umm ok. Whered you get your motor? Is it a 72 or 80v motor? What do you mean p-hp?

Also how far does 7.6 kw get u?

I had a truck load of the motors from a defunct start up ev company.
Down to the last 6 pcs.
Name plate data doesn’t mean much. These were designed for use in 72v car.
38 miles in theory. Steady 25 mph level ground. I have one second person report of 60 miles, but can’t confirm it. @AssyRequired

Oh cool. What company? And what kind of motors, just a standard brushed motor?
Would this work for a motor? How many hp could it out out with a 100ah battery pack? And where could I find the cells and bms to make it cheap? And where would you get a pedal and stuff to make it work?

You would be better off using tested parts.
We make a Gem kit for $1700. Includes 8kw induction motor and Sevcon controller, ready to run.
If you buy something else, I can still help, but it took me two years to get the kit together. So good luck starting over. :slight_smile:

youtube - Bing video grantwest gem&shtp=GetUrl&shid=4c2eadec-fb46-4842-9d95-9173951125ff&shtk=S2VucyBHRU0gY2FyIEFDIENvbnZlcnNpb24%3D&shdk=MjAwOCBFNCBnb2I%3D&shhk=R55LSGH4tujwOJZmJ7F5v2wb8sNpOHVdEI4Y6XGVluQ%3D&form=VDSHOT&shth=OVP.jm5QRh_En9FO6ViAsYWgnQHgFo

What year is your car?

Grant’s 2017
youtube - Bing video grantwest gem&shtp=GetUrl&shid=ca9a9d3a-2c7c-4d90-a747-f7e61c8ad15a&shtk=NTAgTXBoIEdFTSBjYXIgMjAxNw%3D%3D&shdk=R2VtIENhciA1MCBNUEggMjAxNyBHZW0%3D&shhk=X25wOcTuAEf2LLAD0FrzeYDZmmGvGU7OPk8D1QyeCeA%3D&form=VDSHOT&shth=OVP.FV03SXifRT1dpN6u6DyMQgEsDh

Is there any way to get this to top out at 55mph , what kind of motor could do that and fit? And how many volts would it take in power?

Would it need a custom, erm, transmission or whatever?

Start over. What are you starting with?
Something that can stop from 55mph.

I’m sure it’ll slow down enough :man_shrugging:

Im Just trying to see how much it will cost to deal with the drive train and after that I suppose I’ll have to see how to get disc brakes and the cost of that too

@Jatgm1 - You didn’t state what you are basing this on.
What car do you have?
What are your goals here?

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I was going to get an e2 and am seeing a lot of 2002 models. Was hoping theirs some motor that’s ac and capable of a higher speed and Regen braking that would physically fit and propel it about 55.

I would likely only need to go 40 most the time but 55 continuously without damaging the vehicle would be preferred. It’s a 40 or 45 mph speed limit by me