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CT scans of batteries

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Re: CT scans of batteries

#31

Post by kamilner »

joering2 wrote: post #29

How doable (guess not) would it be to make a "gravity battery" ? A tiny but heavy balls are thrown from top and while passing thru thin channels they rotate some sort of mini-dynamo that creates electricity. Once all balls are on the bottom, generated electricity is used to rotate the whole thing and start process anew. Anyone with a napkin can elaborate why this is not feasable?

The amount of energy from a 1 tonne mass dropping 1 meter is about 10,000J (https://www.wolframalpha.com/input?i=%281+tonne+*+9.82m%2Fs%...)

The amount of energy stored in a Tesla is about 100kWh or about 3.6e8J.

You would need 36,660 tonnes suspended by a meter to store an equivalent amount of energy (or 1 tonne suspended 36.7km). https://www.wolframalpha.com/input?i=100kWh+%2F+%281+tonne+*...

Re: CT scans of batteries

#32

Post by addaon »

kamilner wrote: post #31
joering2 wrote: post #29

How doable (guess not) would it be to make a "gravity battery" ? A tiny but heavy balls are thrown from top and while passing thru thin channels they rotate some sort of mini-dynamo that creates electricity. Once all balls are on the bottom, generated electricity is used to rotate the whole thing and start process anew. Anyone with a napkin can elaborate why this is not feasable?

The amount of energy from a 1 tonne mass dropping 1 meter is about 10,000J ( https://www.wolframalpha.com/input?i=%281+tonne+*+9.82m%2Fs%... ) The amount of energy stored in a Tesla is about 100kWh or about 3.6e8J. You would need 36,660 tonnes suspended by a meter to store an equivalent amount of energy (or 1 tonne suspended 36.7km). https://www.wolframalpha.com/input?i=100kWh+%2F+%281+tonne+*...

Or one Tesla Model S (~4600 lbs) suspended 17.6 km. With a range of ~400 miles, this means the storage-Tesla would have to drop ~0.027 units per unit travelled by the drive-Tesla, giving a "glide ratio" of ~36:1, which passes the sniff test on reasonableness.

Re: CT scans of batteries

#33

Post by jonas-w »

haggy wrote: post #17
exabrial wrote: post #14

Even in 2022, hijacking the scroll wheel still isn't cool or 1337.

I disagree in this case. Normally I'd fully agree with you but I think this animation style works really well given their use-case.

Same i normally get so much anger, but in this case it didn't slow down scrolling, also it added functionality instead of "just looking good".

Re: CT scans of batteries

#34

Post by dnfa »

exabrial wrote: post #14

Even in 2022, hijacking the scroll wheel still isn't cool or 1337.

I always thought scroll jacking was taking over the behavior of the scroll? This seems different, as it's using the position on the page to run the animation but not controlling the scrolling behavior.

Re: CT scans of batteries

#35

Post by minitoar »

system2 wrote: post #30
joering2 wrote: post #29

How doable (guess not) would it be to make a "gravity battery" ? A tiny but heavy balls are thrown from top and while passing thru thin channels they rotate some sort of mini-dynamo that creates electricity. Once all balls are on the bottom, generated electricity is used to rotate the whole thing and start process anew. Anyone with a napkin can elaborate why this is not feasable?

No need napkins for it. Because of friction and other forces the dynamo does not generate enough energy to lift the balls back up and have extra to be stored for other uses. In short, you use more energy to lift them than produced. If anyone could invent such a device, the world hunger and money wouldn't be problems anymore and we would be traveling to the end of the universe already.

I’m pretty sure by “generated electricity” they mean from some other source.

Re: CT scans of batteries

#36

Post by real-dino »

I have some LiFePO4 batteries powering my laptop, and onboard electronics on my boat. They are very heavy, but have a super long life. Often forgotten, they are used a lot in automotive applications!

Re: CT scans of batteries

#37

Post by danuker »

joering2 wrote: post #29

How doable (guess not) would it be to make a "gravity battery" ? A tiny but heavy balls are thrown from top and while passing thru thin channels they rotate some sort of mini-dynamo that creates electricity. Once all balls are on the bottom, generated electricity is used to rotate the whole thing and start process anew. Anyone with a napkin can elaborate why this is not feasable?

Switch the balls with water, and the channels with turbines, and you have discovered a hydroelectric reservoir, which is quite feasible, given that quite a few are already built.

> Once all balls are on the bottom, generated electricity is used to rotate the whole thing and start process anew.

If here, you mean part of the electricity generated by the flow, then it can't work because pumping it back up is subject to friction (in fact, generation from when it flows down is also subject to friction) and to mechanical/electrical conversion losses.

On a 100% efficient system with no losses, you would get perpetual motion, but subtracting any energy from the system would make it slow or stop.

Re: CT scans of batteries

#38

Post by scrumper »

Very interesting!

Confused by the text about the alkaline scan (the first one). The +ve side is called the anode isn’t it, not the cathode? And electrons originate at the cathode not the anode. Or is the usual terminology inverted because it’s a battery or this particular type of battery? I don’t know much about batteries; chemistry never a strong suit.

Re: CT scans of batteries

#39

Post by motohagiography »

What a great concept for explaining the inner workings of everyday things. From a product perspective, what a dream to have that available to take the mystery out of what you do. I'm thinking of other hidden mechanisms that people use every day that it would be socially helpful to understand, and the sponsorship ops must be amazing. I suppose there's just some people you can't convince, so a 5G transmitter might not be a great example, but maybe a speed enforcement gun, the secure element on an iphone, SIM, or chip and pin card, the brake caliper of a car with regenerative braking, a high end espresso machine, a top tier audio amplifier, etc.

Re: CT scans of batteries

#40

Post by folmar »

joering2 wrote: post #29

How doable (guess not) would it be to make a "gravity battery" ? A tiny but heavy balls are thrown from top and while passing thru thin channels they rotate some sort of mini-dynamo that creates electricity. Once all balls are on the bottom, generated electricity is used to rotate the whole thing and start process anew. Anyone with a napkin can elaborate why this is not feasable?

The closest that you have in real life is pumped-storage hydroelectric power station.
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