We don't know why lithium batteries work

http://shkrobius.livejournal.com/398842.html

by mike_esspe • 13 years ago

269 105 13 years ago

shkrobius.livejournal.com

damian2000• 13 years ago

Some diagrams here http://electronics.howstuffworks.com/everyday-tech/lithium-i...

Tloewald• 13 years ago

Doesn't address the specific unknown described in the article, but yes, we do know how LIon batteries work, just not how the specific solvent used prevents the batteries rapidly degrading.

waqar• 13 years ago

I read it in 12th :p

meaty3• 13 years ago

Doesn't this apply to all of science?

I mean we don't actually know why anything really works, but we have some models which fit the observations at the moment. This is just a very shallow model i.e. "we poked it and it worked".

raverbashing5• 13 years ago

Exactly!

We know very little. The same goes for the atomic model and a lot of other things.

Electrons, protons, quarks? That's our model. We know the equations, we know how to predict a lot of stuff.

This guarantees nothing. Maybe tomorrow someone comes up with a different theory that explains things better but doesn't say anything about waves or particles. Who knows.

Quick example: what's a magnetic field? It is a measurable quantity, there are theories about how forces are exchanged between charged particles, but essentially it is more a mathematical aid than anything else.

And physics is the most 'hard' science. Easily reproducible, the same everywhere in the universe (as far as we know), experiments can be reproduced as many times as you want without interference.

Now if you go to more specific sciences (biology, medicine, etc) it gets worse. They are only valid on planet Earth for a short period of time, for a start. Test subjects all have differences and experimenting on them affects the results.

jibbirish• 13 years ago

This is the very core of our scientific method (critical rationalism, Karl Popper [1]), theoretical models can only be used in science when they can be falsified. That is why we call them hypothesis (from the Greek word for assumption [2]). Logically, no number of positive outcomes at the level of experimental testing can confirm a scientific theory, but a single counterexample is logically decisive.

For example, we can observe a thousand white swans in the world, and hypothesize that all swans are white. That is until we encounter that one black swan, and our hypothesis has been falsified.

[1] http://en.wikipedia.org/wiki/Karl_Popper [2] http://en.wikipedia.org/wiki/Hypothesis

Confusion• 13 years ago

  This guarantees nothing.

It guarantees a whole lot of things. When necessary, you bet your life on these mere 'models'. These 'models' cause you to trust stepping into an airplane and stepping out of the trajectory of a falling rock.

  We know very little.

We know a lot about these models. We investigate where they hold and where they don't. We don't just know they are valid on planet Earth for a short period of time: we investigate whether they also hold elsewhere and held in the past and have every reason to believe they did and do.

To move on to some philosophical background behind your assertion: the idea that there is some 'real', 'objective', 'true' reality that is modeled by these models, is a pre-Kantian point of view. A post-Kantian point of view is that these models of how the universe works are our reality. They are the only thing we can possibly have knowledge of: the models we use to categorize and structure our observations.

Most of them only exist in our brains. They got there by nature and nurture, without us usually spelling them out. They govern our daily behavior. We've tried to formalize the more complex ones in language that is independent of individual humans.

Sometimes observations are not consistent with a model, so we revise the model. Still we only know the new version of the model, which describes what we expect to observe.

tcgv• 13 years ago

I agree with you. When ever someone argues that we know a lot about the world and how it works, the following quote comes to my mind:

"The universe is not only stranger than we imagine, it is stranger than we can imagine"

J. B. S. Haldane

hakaaaaak2• 13 years ago

Watch it. Next thing you know you'll admit that we don't really "know" anything and get into the realm of metaphysics! But, I agree. In fact, the fallibility of science should be something taught in elementary school along with the scientific principle. It is already taught that science helped us get from "the sun revolves around the earth" to "the earth revolves around the sun", but we are not taught about differences in outcomes of valid scientific studies proving AND disproving global warming and what that really means, which is that science is biased, flawed, and does NOT elucidate truth, but it is helpful and practical in many ways and produces what is currently accepted as "fact".

It is important to have a critical mind when it comes to science and understand that faith doesn't just reside in religion- atheists and those that claim that science have the answer to everything often truly believe that science is a constant or that it "evolves" as some sort of mystical truth that will lead us to enlightenment, but, practically speaking, science is always incorrect. We don't have all of the answers and we never will. Don't get me wrong- science has made huge advancements in our civilization and almost everything we interact with has been produced in part or has been affected by science, often in a good way but not always. However, science is not and never should be a religion. You can use scientific principles and "facts", but if you call it science, do not be beholden to those "facts".

This does not mean that we should give up exploration or research at all. But by accepting the wonder that is everything we don't and will never completely understand, we are all scientists.

illuminate4• 13 years ago

The fallibility of thought and observation should be taught over "science", because otherwise we'll have even more obnoxious pseudoskeptics than we do today, who think that yeah, what does "science" know anyway? Then proceed on with their folksy but ungrounded, still harmful beliefs.

lilsunnybee• 13 years ago

No faith needed, at least for a philosophically grounded scientist. We are never going to get at some essential true nature through science. What we can do is expand our reality and capabilities in the world by creating useful models, and creating new models when the old ones are no longer sufficient.

Almost every person, scientist or no, has personal beliefs in addition to understanding of some of the scientific models we use. The two shouldn't be conflated though.

shardling• 13 years ago

If you think that, you've missed the point of the article.

We know how almost everything we use works -- in that we can connect the initial "shallow" models to more fundamental models of physics. Apparently this one has eluded us so far.

olleicua• 13 years ago

This is a philosophical stance that goes beyond the article's point. We have very good models for most of technology but we don't know enough about how Lithium batteries fit into those models. It's kind of tangential though. The point of the article seems to be that we ought to pay more attention to tangible things that we don't understand (like how to design more efficient batteries that would improve people's lives in real ways) then on pointless interpretations of string theory. I tend to think there is value in keeping in mind that we can't actually be certain of things because the alternatives seems quite pompous to me.

guard-of-terra• 13 years ago

I think his point was that we don't even have a model for Li-Pol battery.

driverdan• 13 years ago

Something makes me suspect this article is missing part of the truth, similar to sites that claim we don't know how bees can fly (we do).

46Bit• 13 years ago

I agree. I've only high school electrochemistry to draw on, but questioning this sort of thing becomes much easier if we focus on the exact claim:

* When reduced, ethylene carbonate forms a dense material that lithium cations can pass through but solvent molecules can't.

* Propylene carbonate does not form this/similar material.

* Using propylene carbonate therefore allows the solvent to come into contact with and weaken the graphite anode.

* Nobody knows the chemical process that forms the material for ethylene carbonate but does not for propylene carbonate.

semenko• 13 years ago

Yeah, this piece is a little misleading. The author is referring to a nuanced difference between ethylene carbonate (EC) and propylene carbonate (PC) in the formation of a protective film around anodes.

See this (paywalled) review of electrolyte chemistry: http://pubs.acs.org/doi/abs/10.1021/cr030203g http://www.ncbi.nlm.nih.gov/pubmed/15669157

""" The unique position of EC as a lithium battery electrolyte was established in 1990 when Dahn and co-workers reported the fundamental difference between EC and PC in their effects on the reversibility of lithium ion intercalation/deintercalation with graphitic anodes.36 Despite the seemingly minute difference in molecular structure between the two, EC was found to form an effective protective film (SEI) on a graphitic anode that prevented any sustained electrolyte decomposition on the anode, while this protection could not be realized with PC and the graphene structure eventually disintegrated in a process termed “exfoliation” because of PC cointercalation. The reason for the effectiveness of the SEI has incited a lot of research interest in the past decade but remains an unsolved mystery, although it is generally believed that EC undergoes a reduction process on the carbonaceous anode via a similar path to that shown in Scheme 1. Because of the important role this SEI plays in lithium ion chemistry, the research efforts on this topic will be reviewed in a dedicated section (section 6). """

runn1ng• 13 years ago

So still, the main claim sort of stands - there are unsolved mysteries in every day's life, which we still don't understand fully, but that we use anyway.

(I know nothing about electrochamistry or batteries :( )

kragen4• 13 years ago

What do you think is misleading about the linked LJ post? The abstract you've quoted here seems to back up every word in it.

mossplix2• 13 years ago

it took a while though ... http://www.livescience.com/528-scientists-finally-figure-bee...

JoeAltmaier3• 13 years ago

Now find the one explaining why when you sit around a campfire, the smoke always comes right at you?

brazzy• 13 years ago

It took a while to understand the mechanism exactly, but it was always clear that it had to do with fluid turbulence, which is extremely hard to model.

The claim that "science says bees can't possibly fly" was always wrong, based on models for static wings that just don't apply, as everyone with an inch of competence knew all along.

brittohalloran• 13 years ago

Not an expert but I find this difficult to believe. We know a LOT about battery chemistry.

VLM• 13 years ago

I think the author intuitively knew that "A slight difference in electrolyte composition results in dramatically different long term electrode reliability" would not get quite as many page views as the completely false "No one has the slightest idea how and why it works." Especially by carefully phrasing the article such that the "it" refers to a hyper detailed corner case but implies its the entirety of mankinds chemistry knowledge, or at least battery chemistry.

So three good PR lessons:

1) Dramatically exaggerate

2) Confuse pronouns... which "it" is the author writing about?

3) Appeal to ignorance, wave away all that science-y stuff in favor of awe and wonder.

Dylan16807• 13 years ago

I thought the article was fine.

1. We really have no idea what the molecules are doing in this protective layer. See the quote from an actual paper in semenko's post.

2. The it is the bit that makes lithium batteries not fall apart.

3. What the hell are you talking about with appeal to ignorance? The article is just explaining that there are gaps in our knowledge, basic science that we can measure, use, tweak but don't know the mechanism. There is no attempt to prove or disprove anything.

smsm422• 13 years ago

The author of the article is, however, an expert. In chemistry (among other things). And the fact that we know a lot about chemistry of some other batteries does not in any way makes it impossible that we know very little about the chemistry of this specific one.

kragen4• 13 years ago

It sounds like you're familiar with the author previously, and know them to be a polymath. What is their background?

JoeAltmaier3• 13 years ago

Easy to claim in chemistry - where loads of research is done by simply trying everything and seeing what works. Its no longer interesting to understand why. Medicine, industrial processes, it doesn't matter. I read once that the last medicine designed by a chemist was the cure for syphilis - decades ago. Probably not true any more, but lots of Edison-style 'science' is being done still.

mossplix2• 13 years ago

Theory dictates what you try out though .... What cure of syphilis is that? I though Antibiotics are the cure.

illuminate4• 13 years ago

"where loads of research is done by simply trying everything and seeing what works."

Do you seriously think research is "throwing shit against a wall and seeing what sticks"?

"I read once that the last medicine designed by a chemist was the cure for syphilis - decades ago"

Yet another folksy anecdote parroted by the same people who claim "the last disease we've cured was Polio". Saying these things does not make them true.

Alex39172• 13 years ago

"Do you seriously think research is 'throwing shit against a wall and seeing what sticks'?"

That's exactly what most pre-clinical research is. Testing hundreds of thousands of different molecules in hopes of finding on that works. For every NME that makes it onto the market, there are several thousands or tens of thousands that are initially tested.

Alex39172• 13 years ago

"I read once that the last medicine designed by a chemist was the cure for syphilis - decades ago."

http://www.vice.com/read/interview-with-ketamine-chemist-704...

akiselev9• 13 years ago

Producing, understanding, and testing the vast number of chemical interactions are vastly different fields of chemistry (and biology). There are many researchers working on understanding the basics of electrochemistry which can lead to a better understanding of this phenomena, even if they're not specifically looking at this example.

However, those are probably in the minority compared to these "Edison-style" scientists, as you call them, and for good reason. Phenomena not yet explained by scientific cannon are vastly outnumbered by the possible number of configurations and combinations of chemicals that we have yet to explore. We can't just dedicate every chemist in the world to the problem of understanding the fundamental laws of chemistry and hope to get anywhere. Science just doesn't work like that.

Identifying and testing chemicals that have applications in medicine or industry has massive impact all over the world and is easy relative to a fundamental understanding of nature. What use would science be if it was mostly dedicated to understanding, instead of applying its knowledge to the needs of its people?

Besides, what we can discover and learn about the natural world is often heavily limited by the progress of technology, especially in industry. The incredible proliferation of personal computers and the constant downward force on cost and energy consumption of CPUs, GPUs, and storage in the last two decades has made the LHC possible today. Imagine building a super computer 20 years ago just to store, let alone analyze, all of the data coming out of the collider's instruments. We may have lots of technology to take snapshots or do "traces" of chemical reactions but we are still quite limited in our ability to "see" live chemical reactions (and the methods require expensive equipment).

jpxxx2• 13 years ago

I like the side-point this author makes. Anytime there's a new discovery in quantum theory or some other escoteric, sexy area of research, thousands of armchair scientist knowitalls fall all over themselves to decry or incorrectly interpret what's been found.

Ask a basic question on physics, biology, or engineering and only an actual scientist will pipe up. I blame science fiction novels.

bollockitis• 13 years ago

I think the big difference here is that quantum theory and string theory hold enormous implications for the nature of reality. Understanding these concepts, even on a basic level, ignites in us a sort of spiritual fascination with the universe. That's why they are sexy. It has nothing to do with science fiction novels. It's just that understanding the mechanics of a vacuum cleaner doesn't leave us in awe of the universe.

6ren• 13 years ago

I think you're right about motivation, but that's about ego and fame within a social hierarchy. Someone who loves understanding for its own sake also loves understanding the little bits - and they are better at it, because their attention is not divided, and they are open to serendipity. One can't predict where understanding will come from e.g. the motion of a spinning plate.

One could only be sure that understanding a vacuum cleaner is unrelated to understanding the universe in hindsight.

icelancer• 13 years ago

>Ask a basic question on physics, biology, or engineering and only an actual scientist will pipe up.

Evolution/creationist crackpots?

dalke2• 13 years ago

To be fair, if there's a new discovery related to evolution, you are likely to get non-scientists to respond. Granted, those will be people who argue that Darwinism is an evil, false influence in the world, but biology still has its own knowitalls.

Or, look at controversial topics in other domains of science: AIDS was created as a biological weapon, vaccines cause autism. Fluoridated water is a Communist plot to "deplete the brainpower and sap the strength of a generation of American children." The WTC could not have fallen because of planes crashing into it, and must have been leveled due to planned explosives.

This holds even outside of science. Ask a question on copyright laws and a bunch of people with no formal law training (including me) will chime in - leading to complete ripped movies on YouTube prefixed with the magic phrase "fair use."

loceng2• 13 years ago

You sure know your conspiracy theories.

ekianjo4• 13 years ago

You forgot "JFK was not killed by Oswald" and "We did not go on the Moon". Apart from that, you should avoid putting ridiculous conspiracy theories next to more believable ones. The fact that governments can and do stuff is secret and cover it up is hardly a "theory" anymore, wikileaks should ring some bells. Always believing what is written in the History Books sponsored by government oversight does not mean you are being fed the truth. Everyone has their own agenda.

jere• 13 years ago

It's like reverse bike shedding. Bike sheds have proved too boring for anyone to actually care about their color anymore.

vacri• 13 years ago

Online, perhaps. But get involved in meatspace and bikeshedding is flourishing like always.

rbanffy2• 13 years ago

> I blame science fiction novels.

I personally blame self-help literature that borrows scientific terms to construct a fantasy magical world where their readers can actually help themselves by [insert stupid idea here].

And I cringe when someone says something represents a "quantum leap" from something else.

alizaki• 13 years ago

I always wondered why everything related to my computing devices seems to follow some variation of Moores law but the battery. This explains it.

kragen4• 13 years ago

I don't know if this is really the reason. Moore's Law started with planar photolithographic silicon semiconductor integrated circuit fabrication (aka making chips) around 1958. We're now in year 50 of planar photolithographic silicon semiconductor integrated circuit fabrication, although now we have environmental laws so we can't just dump hydrofluoric acid into the groundwater, and we have to use X-rays instead of ordinary light, and we worry about smaller dust, stuff like that which makes it a lot harder. But basically we've just been scaling stuff down. We have about another ten years before we reach the physical limits of planar photolithographic silicon semiconductor integrated circuit fabrication, which are about two orders of magnitude away. That means we started about 17 orders of magnitude away.

By contrast, we seem to have reached the fundamental limits of carbon-zinc batteries a couple of centuries ago, and the fundamental limits of ordinary electrolytic batteries in 1990 with the invention of the lithium battery. (Or maybe the zinc-air battery.) The fundamental limits on chemical energy density seem to be about two or three orders of magnitude from where we started, not 17.

In both cases it's possible to do better by using fundamentally different approaches: microturbines, tiny fuel cells, or betavoltaic batteries in the case of batteries; diamond, three-dimensional structures, and molecular assembly in the case of electronics. But all of these have substantial engineering obstacles.

ricardobeat• 13 years ago

I also wonder about the "graphene sheets" - it's not the first time I read that on the description of a battery. Surely it's graphite, not graphene? I don't think batteries are built with one-atom-thick layers.

akiselev9• 13 years ago

Yes the early batteries used graphite (graphene was already proposed as a theoretical possibility but not replicated in a lab setting until 2004).

However, with its discovery, graphene has been extensively researched for batteries and more is ongoing. Graphene is used in the manufacturing process for some lithium batteries where I assume it is used to build the graphite porous structure with fewer impurities and with better control of its composition. (total speculation).

jcromartie• 13 years ago

He means graphene that's incidentally always there in graphite ("in graphite in the anode"). We didn't coax it into sheets, it's just there and it's what makes things happen.

Noughmad• 13 years ago

Graphite is composed of multiple sheets of carbon atoms, while graphene is composed of a single such sheet. Referring to the sheets as "graphene sheets" is not very incorrect, but sounds much cooler.

noonespecial• 13 years ago

We may not always know how or why (at the deepest fundamental levels). We don't need to. We use science to know that it does.

daniel-levin• 13 years ago

> Still no one knows what chemical process yields this material, what is this material, and why a small structural change in the electrolyte makes such a colossal difference in the performance

I read this an immediately saw a parallel with computer science. To quote from CLRS: [1] "Computer scientists are intrigued by how a small change to the problem statement can cause a big change in the efficiency of the best known algorithm". It strikes me as incredible how seemingly simple concepts can be the tip of a much bigger iceberg of complexity. Another example of this would be the proof of Fermat's Last Theorem [2] . A proposition one can understand with primary school mathematics, whose proof eluded mathematicians for centuries and required the invention of new mathematics. Sir Andrew Wiles, the person who proved the proposition, had to see deep symmetries between a plethora of domains in mathematics. The main idea that I find remarkable is the incredible complexity of the world in which we live - even the smallest of changes to a concept we think we understand (Electrochemistry, Algorithms, Mathematics), can redirect the trajectory of our understanding completely. To me, this seems as if we have only the most superficial understanding of the myriad structures and substructures of the universe. New developments in all areas of science excite me greatly purely because our understanding has been advanced that infinitesimally bit more.

[1] http://en.wikipedia.org/wiki/Introduction_to_Algorithms [2] http://en.wikipedia.org/wiki/Fermat%27s_Last_Theorem

stcredzero• 13 years ago

We didn't know exactly why lots of pharmaceuticals worked either, and we still don't in some cases.

balsam• 13 years ago

a digression but the writer seems russian by virtue of his/her sentence construction. I can't really pin down the reason, perhaps a linguist can help me out? (Disclaimer: I'm not russian. Edit: By the comments on his page it looks it's actually a russian. Also the use of livejournal)

loceng2• 13 years ago

Related to not knowing why lithium works in the brain?

jimbokun• 13 years ago

"“Science literacy” tests quiz the initiated on their command of abstract dogmas acquired through no exercise of one’s ability to generate knowledge."

This is something that often bothers me about the r/atheism crowd.

A young person encountering an idea like evolution for the first time should be extremely skeptical and require much convincing, because it is not an intuitive idea at all. Believing in it just because the teacher says you will get a bad grade on the test if you don't does nothing to inculcate scientific thinking in young people.

Now, students unwilling to engage with physical evidence obviously have a different problem. But with the level of discourse I see coming out of many proponents of atheism on the Internet, I often feel many of them are proud of their "command of abstract dogmas" and are not particularly people demonstrating the "ability to generate knowledge."

Centigonal• 13 years ago

Personally, I thought evolution through natural selection was pretty intuitive and obvious, given the previous instruction on how DNA and chromosomes worked. If everything changed a little bit, and only the good changes stayed, then they'd all stack up and constitute a big change!

DNA and chromosomes were pretty unintuitive, but we have pictures of those, so that helped.

Also, I think Occam's razor applies even if you're a young person who hasn't heard of it yet: with no previous knowledge on the subject, I am wont to accept the simplest explanation that doesn't contradict reality without much skepticism.

username3• 13 years ago

Presuming everything will follow a linear path is simple.

rbanffy2• 13 years ago

> A young person encountering an idea like evolution for the first time should be extremely skeptical

Not really. Evolution follows directly from hereditarity and natural selection. We turned wolves into shih-tzus through artificial selection. From that point, it's natural to imagine what natural selection does to the population.

I often find useful to use a disadvantageous trait as an example. If all your family is, say, allergic to peanuts and all you have to feed your tribe is peanuts, your family will probably leave less descendants than those who can eat. With a couple generations, this trait will be eradicated.

We don't know why lithium batteries work

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