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I'm planning to build a scratch built cyclecar inspired by the turn of the (20th) century machines. While I've long assumed it would be ICE powered the E option resurfaces. I find there are plus and minuses to any option of power but want to learn more about the electric choice before I go much further with design.

This will be a very small, light, car with no frills. The key word is minimalism. Since many electric cars managed to be built before the computer age my interest in electric power for this project pretty much hinges on being able to forego anything with a chip.

My hope is that some sage person can direct me to sources where one can learn, get advice, tips, etc. and input is greatly appreciated.
 

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Hmmm. Best of luck. You might be able to build something without any chippery, but I suspect you would want a battery management system. It needn't be "obvious", but you would want it. I presume you would use Li-Ion or maybe LiFePO4. There are numerous companies who will sell battery packs with but in BMS systems/charge controllers.
 

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Maybe base it in a bunch of e-bike components? It could be pretty sport if you had a powered hub on each wheel. :)
 

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I'm planning to build a scratch built cyclecar inspired by the turn of the (20th) century machines. While I've long assumed it would be ICE powered the E option resurfaces. I find there are plus and minuses to any option of power but want to learn more about the electric choice before I go much further with design.

This will be a very small, light, car with no frills. The key word is minimalism. Since many electric cars managed to be built before the computer age my interest in electric power for this project pretty much hinges on being able to forego anything with a chip.

My hope is that some sage person can direct me to sources where one can learn, get advice, tips, etc. and input is greatly appreciated.
It's very scattered across multiple sources I am afraid. There will be no handy guides for that.

What I will offer you though are the following thoughts; you have to figure how to control your electrical power. Pre-ICE EVs often had DC motors with several windings. By switching in more of the windings you got more power.

Effectively there were several motors in one housing, if you like, and to get more power you turn more motors on. As no-one would make such DC motors any more for EV level powers, maybe one way is to think about how you might parallel up a series of separate DC motors, and do similarly to those early machines.

You can get e-bike motors up to 3kW.

Of course, your problem is that if you have too much power and if it is not a pedal machine then you'll have to register it for road use and subject it to an SVA or whatever the process is these days.

The only way to control power to a single motor is to switch the power on and off quickly, because you can't really use a great big resistor, it would need to be as powerful as the motor itself and the battery would basically be delivering full power all the time, ergo would last minutes only. I don't know when the rheostatic chopper was invented and made, but this is the device in post-war milk floats. It is a mechanical device where a rotary contactor repeatedly closes. That's the buzz noise they make when they pull off, because the switching speed is a few 10's Hz.

With silicon switching, the switching can be done in the 4 to 16kHz range, and the frequency is increasing as more refined electronics comes along. The on board chargers will be operating in the 40kHz range, but the more power you put through a transistor the slower it can be made to switch. The more switching time you have the less efficient it is, so there is a point where you don't really want to switch faster it just brings in inefficiencies.
 

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Slightly off the wall suggestion, but I'd scour various RC model forums for info, its might be better to scale up those solutions than scale down full blown EV ones for your project.

I wouldnt dismiss chips out of hand, modern RC speed controllers are lots better, smaller and run cooler (which would translate to bit of extra range) and much like a computer I doubt you need to know exactly how they work in order to plug them in and use them.

Also if you want decent range,power or longevity from batteries you are probably going to need to use some batteries with modern chemistry and when in packs those will need balancing carefully and I'd imagine that an electronic battery controller would do that much much better than you would.

If you Google Jay Leno he has restored a very early Baker electric car and some pieces he has put onto You Tube go into some detail which you might be able to get some ideas from. FWIW he has also taken a senisble step of modernising some of the components. Sometimes modern is simply better, classic car restorers often think nothing of replacing dynamos with alternators or drum with disk brakes and at the very least I expect that a modern speed controller would also fit in more with your ideas of minimalism.
 
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