Supercapacitor

Does anyone know if I can put a supercapacitor on my electric motorcycle. If so what will it do thanks

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Yes you can put one on your bike. It will make it heavier and more expensive. Many people have tried this out but currently available supercapacitors have only a tiny fraction of the energy density of lithium batteries. It’s much better to add more batteries.

Ok thank u

One thing that's worth noting is that a supercapacitor bank in parallel with a lithium battery will only do valuable work in between the resting voltage of the battery and the loaded sag voltage of the battery. That's a tiny fraction of its already tiny energy storage. The rest of the time it will mostly function to make the plug-in or switch-on sparks between the battery and controller more destructive than they would be otherwise.

Chalo said:

One thing that's worth noting is that a supercapacitor bank in parallel with a lithium battery will only do valuable work in between the resting voltage of the battery and the loaded sag voltage of the battery. That's a tiny fraction of its already tiny energy storage. The rest of the time it will mostly function to make the plug-in or switch-on sparks between the battery and controller more destructive than they would be otherwise.

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Obviouly, you'll need something more 'intelligent' than that - a separate charge/discharge circuit of course.
But even for something very specific like electric drag racing or something you'll be better off with LTO.

I think it could be a good way to get decent current discharge even from a weak battery. Basically you only need high current during a few seconds while accelerating, the rest of the time you don't need nearly as much. Weak batteries will have lots of voltage sag under load, lowering the bike's performance, but that can be compensated with supercaps in parallel with the battery which will deliver current instantly and then recharge whenever the load decreases (meaning you probably need something to limit the caps charge speed, because otherwise it will just add even more load to the battery)
So this could potentially give you more instant power while protecting the battery at the same time.
Aside from the added cost and complexity, I don't see any significant drawback.

I don't see any problem with sparks and whatnot: nowadays people use BMS, these things can ramp up the current at startup to avoid inrush so that is a problem of the past.

That's actually something I always wanted to try, just never really had the opportunity yet. Would be nice to see someone sharing some actual experiments on such system.