Flywheel Hybrid Cars

[ChewChewTrain]

https://www.youtube.com/watch?v=4PcIt0FPvWQ

If ICE cars could spin up a flywheel while idling at a stoplight this could add a few more years to their product lifecycle.

[ChewChewTrain]

Why don't electric cars use flywheels if they have a virtually infinite energy density?

https://www.quora.com/Why-dont-elect...energy-density

[OliverGT]

hmm, that Youtube video is from 2008? Not seen or heard of any flywheel cars recently.

I do remember hearing a long time ago about flywheel technology they were planning on using in buses, so it would be spun up at the bus stop and then the stored energy used to get to the next stop. I think the problem was the weight of the flywheels required and how dangerous they can get when spinning fast.

Wikipedia has a reasonable page on these systems with details on what happens when they go wrong.

Oliver.

[ChewChewTrain]

Originally Posted by OliverGT

hmm, that Youtube video is from 2008? Not seen or heard of any flywheel cars recently.

I do remember hearing a long time ago about flywheel technology they were planning on using in buses, so it would be spun up at the bus stop and then the stored energy used to get to the next stop. I think the problem was the weight of the flywheels required and how dangerous they can get when spinning fast.

Wikipedia has a reasonable page on these systems with details on what happens when they go wrong.

Oliver.

Oh, yeah. I now remember seeing that about buses.

There's usually a technical solution to a safety problem. For example, you ever accidentally short a standard car battery? You'll nearly weld something to your car. Now, imagine the same short happening with today's EV battery pack! The point I'm trying to make is that flywheel safety issues could have been solved, too.

I'm guessing the investment/market timing for flywheel car tech was never right.

ICE cars could have greatly benefited from spinning up a flywheel when a car is idling at stoplights.

[trollbait]

The safety solutions add to the weight and cost. The Formula 1 teams there were using flywheels have dropped them for batteries. I don't think potholes were something they had to worry about in terms of getting the tech to consumer cars.

Flywheel failures could likely be described as 'spectacular'. Tesla has shown that battery failures can be contained and controlled to allow the car to pull over and everyone get out.

[ChewChewTrain]

Originally Posted by trollbait

The safety solutions add to the weight and cost. The Formula 1 teams there were using flywheels have dropped them for batteries. I don't think potholes were something they had to worry about in terms of getting the tech to consumer cars.

Flywheel failures could likely be described as 'spectacular'. Tesla has shown that battery failures can be contained and controlled to allow the car to pull over and everyone get out.

That's most interesting. If F1 design engineers eschewed flywheels for batteries, assuming BOTH were allowed equally, thiss says a lot about battery tech superiority over flywheels.

[trollbait]

Originally Posted by ChewChewTrain

That's most interesting. If F1 design engineers eschewed flywheels for batteries, assuming BOTH were allowed equally, thiss says a lot about battery tech superiority over flywheels.

F1 rules might have played a role, I know that they detailed the size of the KERS(kinetic energy recovery system) and how much energy could be recaptured in a lap or some such.

Another factor for flywheels on cars is that you need two spinning in opposite directions in order to negate any affect on handling and braking.

[R.I.D.E.]

When is the last time F1 technology moved directly to the worldwide transportation environment?

Hydraulic accumulators peak efficiency? 99%. Heard of any accumulator failures bringing down an aircraft?

NASA flywheel battery uses composites (explosive failure is a non event), survives 6g acceleration forces, holds 98% of a charge for 6 months and can discharge its energy in a small fraction of the time required by a chemical battery.

If you have ever messed with a flywheel you might understand the dynamics better. Every wheel on your car is a flywheel.

[R.I.D.E.]

10 KWH flywheel battery the size of a gallon paint can?

[trollbait]

And how much does the flywheel NASA has cost?