[HN Gopher] CT scans of batteries
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CT scans of batteries
Author : vitruvius
Score : 311 points
Date : 2022-10-20 15:11 UTC (7 hours ago)
(HTM) web link (www.scanofthemonth.com)
(TXT) w3m dump (www.scanofthemonth.com)
| throwayyy479087 wrote:
| Those tabs on the final item are what caused the Bolt fires. The
| manufacturing was incorrect, and they had to replace every cell.
| vitruvius wrote:
| The LG lithium ion cell that's second on this page is the one
| inside the Tesla Model Y battery pack.
| anon946 wrote:
| That's interesting and somewhat surprising. I'm not
| knowledgeable about battery design by any means, but I would
| have thought that there would be a better way to make a battery
| pack for a car than connecting thousands of small batteries
| together.
| jaywalk wrote:
| Thank you. I was just about to come back here and ask where it
| was.
| s0rce wrote:
| Sigray has some really cool battery examples
| https://sigray.com/batteries/
| Zak wrote:
| > _We used the measuring tools in our Voyager analysis software
| to decode the model number: it seems to mean that the battery is
| 21mm in diameter and 70mm tall._
|
| Or they could just read
| https://en.wikipedia.org/wiki/Battery_nomenclature, which
| describes the relevant IEC standard.
| haggy wrote:
| This is not really surprising considering that it's basically a
| (very cool) marketing article for their equipment.
| newaccount74 wrote:
| I'm pretty sure that sentence was supposed to be a joke. First
| of all, everybody knows this, secondly you really don't need a
| CT scanner to measure the diameter of a thing.
| sneak wrote:
| I didn't know this.
| [deleted]
| motohagiography wrote:
| 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.
| another_story wrote:
| Can CT scans be used to create 3D models with internal
| components?
| exabrial wrote:
| Even in 2022, hijacking the scroll wheel still isn't cool or
| 1337.
| dnfa wrote:
| 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.
| haggy wrote:
| 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.
| jonas-w wrote:
| 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".
| fdr wrote:
| I did find it useful to scroll up and down with care to
| understand their annotations in detail.
| boboche wrote:
| No 4680 cells, its 2170.
| moffkalast wrote:
| Still very cool, and it shows the single tab connection that's
| the bane of old cylindrical cells that the 4680 solves.
|
| I do wish Samsung would already release some of them to the
| public ffs. Surely they can come up with a price that would
| beat what Tesla's offering for bulk and sell it on the open
| market.
| baybal2 wrote:
| ggreer wrote:
| Only the Model Ys that come out of the Texas factory have 4680
| cells, and their production volume is still ramping up.[1]
|
| 1. https://twitter.com/Tesla/status/1571037989282906112
| yanowitz wrote:
| Pairs nicely with this great book about all kinds of electronic
| components -- https://nostarch.com/open-circuits
| holoduke wrote:
| I like the way the website uses the animation. Well done.
| sam1r wrote:
| >> Create an account and continue browsing on a computer to
| experience the demo assets.
|
| Super cool, but requires account to check out a scan-which won't
| work on mobile regardless, fyi.
| londons_explore wrote:
| The Tesla 2170 cell has a big hole down the middle of it...
|
| That seems like a missed opportunity for a watercooling pipe, or
| anything else to use that space effectively.
| oliveshell wrote:
| I haven't read the paper, so I can't comment on its merit, but
| it appears you're not the first to have that idea:
|
| _Performance assessment of a passive core cooling design for
| cylindrical lithium-ion batteries_
| https://doi.org/10.1002/er.4061
| baybal2 wrote:
| Cylindrical cell life is limited by graphite expansion.
|
| You can only have a roll that long before tension from anode
| expansion will start mechanically damaging it.
|
| Manufacturers intentionally leave some free space to let the
| roll expand, and shrink
| withinboredom wrote:
| I somehow suspect water and electricity after a crash don't mix
| well...
| gambiting wrote:
| I mean, those batteries are liquid cooled anyway.
| dsalzman wrote:
| The company behind these scans is https://www.lumafield.com/ - a
| really cool way to do marketing for your product. Love it!
| saxonww wrote:
| I was thinking this is "will it blend?" applied to some
| company's product. Looks like they sell industrial CT equipment
| and software.
| yieldcrv wrote:
| raydiatian wrote:
| Glad they finally did more scans, and released the backlog of
| them. Having so much nostalgia reading through the game boy
| scans.
| joering2 wrote:
| 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?
| system2 wrote:
| 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.
| minitoar wrote:
| I'm pretty sure by "generated electricity" they mean from
| some other source.
| folmar wrote:
| The closest that you have in real life is pumped-storage
| hydroelectric power station.
| kamilner wrote:
| 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+*...
| addaon wrote:
| 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.
| danuker wrote:
| 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.
| scrumper wrote:
| 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.
| derkades wrote:
| As I understand it, the cathode is where electrons "leave", the
| anode is where they "enter". In case of a battery, electrons
| leave the minus side. But for a device being powered, electrons
| enter the minus side.
| caf wrote:
| Here's how I was taught to remember it: The cathode is purr-
| sitive.
| real-dino wrote:
| 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!
| caf wrote:
| LFP pouch cells are what the Tesla Model 3 and Y RWD from
| Gigafactory Shanghai use.
|
| They'd be ideal for home batteries you'd think - I wonder when
| they'll switch the Powerwall.
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(page generated 2022-10-20 23:00 UTC)