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Li-Ion With 300% More Power, Minutes to Recharge

Battery Nut writes "Altair Nanotechnologies claims to have found a way to reduce Li-Ion recharge time to minutes, as well as increase battery power by 300%, according to this press release. Seems they have received some good feedback by certain experts about thier work: "Two eminent experts in battery technology, Dr. K. M. Abraham and Dr. Vassilis G. Keramidas, have expressed strong support for Altair's work. " So is it a new revolution in battery technology, or hopeful hype? Stay tuned, their quarterly conference call is Thursday Feb 24th at 11AM." Anyone else think snake oil?

50 of 408 comments (clear)

  1. Snakeoil? by IainMH · · Score: 3, Funny

    No - It's lithium.

    1. Re:Snakeoil? by khrtt · · Score: 4, Informative

      Current lithium batteries are slow to recharge because they have a high internal resistance, and low tolerance for overvoltage. A typical battery cell with 3.6V idle voltage takes no more than 4.3V when charging, and the .7V drop over the internal resistance allows very little current through the battery, which is why it takes 3hr to recharge fully.

      The article gives no details, but they talk about nanomaterials in the elctrodes. My best guess would be, they came up with a way to increase the surface area of the electrode, lowering the internal resistance a 100 fold or so. Expect this battery to explode in your face if shorted.

    2. Re:Snakeoil? by drinkypoo · · Score: 5, Insightful

      I'll just expect this battery to come with an internal fuse, instead.

      --
      "You're right," Fisheye says. "I should have set it on 'whip' or 'chop.'"
    3. Re:Snakeoil? by tlhIngan · · Score: 5, Informative

      Current lithium batteries are slow to recharge because they have a high internal resistance, and low tolerance for overvoltage. A typical battery cell with 3.6V idle voltage takes no more than 4.3V when charging, and the .7V drop over the internal resistance allows very little current through the battery, which is why it takes 3hr to recharge fully.

      Actually, LiIon has a low internal resistance - it's somewhere between that of NiCd and NiMH chemistries (when new). However, as it ages (i.e., the moment it leaves the factory), the internal resistance gets higher and higher until it can no longer usefully power the load (generally 2-5 years after manufacture).

      The reason LiIon is slow to charge is because it requires a complex charge regimen. Plus you can't trickle charge them (destroys them). So you charge them at a constant current up around 90% or so, then switch to constant voltage until the cell stops accepting charge. Then you stop and switch off the charger until it drains to around 95% (estimated), and do a CV charge again.

      The end result is you get around 90% charge very quickly, but the last 10% take forever as the charger puts in less and less current.

      Charge it incorrectly and they go boom.

    4. Re:Snakeoil? by Dun+Malg · · Score: 4, Informative
      But what if the fuse doesn't work? Then you're still left with an exploding battery. Then what?

      WTF are you talking about? A "fuse [that] doesn't work" is one that's already burned out. There is no such thing as a "defective" fuse that lets way too much current through. Fuses are safety devices. Fuse manufacturers are very careful for reasons of liability. Your "what if" is as irrelevant as "what if tires were TRIANGULAR?"

      --
      If a job's not worth doing, it's not worth doing right.
    5. Re:Snakeoil? by bluephone · · Score: 3, Funny
      Your "what if" is as irrelevant as "what if tires were TRIANGULAR?"

      I have a patent on triangular tires.

      --
      jX [ Make everything as simple as possible, but no simpler. - Einstein ]
  2. Snakeoil???? by lecithin · · Score: 5, Interesting

    Not everybody thinks so. Altair's stock has gone from $2 to $4+ this past week. It topped out at over $6 last Friday. Their average volume is at 6.6 Million. Yesterday, they doubled it.

    --
    It could be worse, it could be Monday.
    1. Re:Snakeoil???? by quanminoan · · Score: 3, Insightful

      Investors are by no means scientists - you should never judge a scientific discovery by its effect on the stock market...

    2. Re:Snakeoil???? by Dr.+Evil · · Score: 4, Insightful

      There's a whole school of daytraders who base their speculations on hype. Hype being more predicatble than innovation.

      The only question is... do you dump the stock before the conference call, or do you expect the hype to endure?

      But yeah, 6500mAh AA cells? Not in one press release.

    3. Re:Snakeoil???? by MindStalker · · Score: 3, Informative

      Doing fine? Their current stock value is sco 4.06 that compares to 20 dollars a year and half ago.

      Note: anyone looking for SCO look up SCOXE, it used to be SCOX, but now SCOX is someone else.... very confusing.

  3. Hmm... by Anonymous Coward · · Score: 5, Funny

    "Anyone else think snake oil?"

    Someone's trying not to look so stupid this time around...

  4. Hmmm... by clawDATA · · Score: 5, Funny

    Maybe it uses cold-fusion?

    --
    "This is totally insecure, but very convenient."
  5. Slashdot: home of stock pumpers? by Takeel · · Score: 5, Insightful

    When did Slashdot start posting messages from stock pumpers?

    1. Re:Slashdot: home of stock pumpers? by m50d · · Score: 5, Funny

      Since Taco realised he could buy the stock just before posting the story? :)

      --
      I am trolling
  6. Mirror by Anonymous Coward · · Score: 3, Informative
  7. Genetic Experiments? by bigtallmofo · · Score: 4, Funny

    I RTFA and couldn't figure out the precise technique that Altair Nanotechnologies used to breed this super-Lion with 3x the power of a regular lion.

    --
    I'm a big tall mofo.
    1. Re:Genetic Experiments? by WhatAmIDoingHere · · Score: 4, Funny

      They took your standard lion and grafted four asses to it.

      --
      Not a Twitter sockpuppet... but I wish I was.
    2. Re:Genetic Experiments? by bigtallmofo · · Score: 3, Funny

      I agree that they'll make a mint if it's true! But if these super-Lions ever escape from whatever zoo or nature preserve we put them in, it will mean a heap of trouble!

      --
      I'm a big tall mofo.
  8. Actually, 200% more power by CrazyWingman · · Score: 4, Insightful

    Someone needs to go back to math class. The article actually says the batteries will have "three times the power" of today's batteries. That amounts to 200% more power, not 300% more.

  9. Electric Cars? by tonywestonuk · · Score: 4, Interesting

    A recharge time of 2 mins is about the same time it might take me to refill my car, So this makes it quite viable as an alternative 'fuel'.... However, the cables from the 'pump' would have to be hugely thick to carry that sort of power.

    1. Re:Electric Cars? by Jeff+DeMaagd · · Score: 4, Informative

      Generally, cables need to be large to carry lots of current. Power isn't directly involved. You could double the voltage, keep the current the same and significantly increase the power involved without being less safe. A cable's capacity ratings are in current and the breakdown voltage of insulation.

    2. Re:Electric Cars? by forand · · Score: 4, Informative

      You cannot do this while charging a battery. The voltage MUST be kept below the voltage of the battery or you will start doing funky things with the battery.

      This is more clear when you realize that current is exactly what is needed to charge a battery. The battery needs to move electrons from one pool to another this is moving current.

    3. Re:Electric Cars? by StressedEd · · Score: 3, Insightful
      I think the parent poster is referring to the ohmic losses due to transmission of power. Power dissipation is proportional to current squared.

      P = I^2 R

      for an Ohmic system (any sensible cable), so if you want your cables to remain cool, I must be reduced, hence V increased.

      This is of course why national grids are at 10s-100s of KV.

      Of course once you want to use it to charge a battery, you have to use a transformer (or equivalent) to reduce the voltage and increase the current, something that would have to happen as close as possible to where the battery is.

      Having said all that, I can't see petrol station forecourts dispensing a heady mixture of petrol and 10KV high power spark machines just yet, at least not with guys like this around! ;-)

      --
      Be nice to people on the way up. You will meet them again on your way down!
  10. BatMax is better! by ghoti · · Score: 3, Funny

    We don't need this crap, we have BatMax!

    --
    EagerEyes.org: Visualization and Visual Communication
    1. Re:BatMax is better! by Alsee · · Score: 4, Funny

      Oh CRAP! I tried putting a BatMax sticker on one of these new Super Li-Ion batteries. . . . there was this blinding flash of light and I got sucked into some bizzaro alternate universe where George Bush was re-elected! CRAP CRAP CRAP! This SUX!

      -

      --
      - - You can't take something off the Internet! That's like trying to take pee out of a swimming pool.
  11. Seems almost reasonable by Anonymous Coward · · Score: 5, Informative

    According to the article, they use a Lithium titanium oxide nanomaterial. Best gues, the nanocrystals typically have little or no stress and a low defect density, as well as an extremely high surface to volume ratio. All of these should improve the efficiency and speed of the battery operation. This might also increase the speed that the battery can discharge. Of course, I am not a battery specialist. Just in nanomaterials development. Might not be snake oil. Assuming all the accolades are true... well, Altair doesn't have a reputation for falsifying data. I look forward to seeing this develop.

    1. Re:Seems almost reasonable by Alceste · · Score: 5, Informative

      That's actually not true. Nanometer sized crystals have large surface to volume ratios than bulk crystals, creating more surface defects per unit mass. The defects within a bulk crystal can be annealed to an equilibrium number, the same as those in a nano-crystal per unit mass. Thus, since battery performance is based on unit mass, you need the name weight of nano-crystals or bulk crystals to get the same capacity (to an order of magnitude, some papers show that surface defects actually INCREASE capacity, nifty stuff).

      In addition, Li(z)Ti(x)O(y) is a system that undergoes phase changes during Lithium intercalation and deintercalation (as the battery discharges the "z" goes from 1 to 0). So the crystals are being made a-new with each charge discharge cycle (increasing cycle life, but this is something that also happens in the bulk, no need for nano whatnot).

      Interestingly, the energy/power density with lithium titanium oxides is actually lower than that for carbons. A battery with a lithium cobalt oxide cathode and a lithium graphite anode will have a maximum potential of 4.2 V. The battery in question in the article actually sits around 3.0 V.

      Finally, the failure mechanism for lithium ion batteries is not the anode, but the area just outside the anode called the SEI layer. This is a passivation layer formed adjacent to the anode by reaction of the neutral lithium with the organic electrolyte. This layer forms initially by irreversibly consuming some lithium, but if the charge/discharge rate is moderate it becomes stable and actually protects the anode. If the charge/discharge is too high, though, the layer breaks and more lithium is consumed to repair it, thus diminishing capacity. After enough of these cycles the batter will dramatically lose capacity.

      Thus, the breakthrough in question must deal with a way of maintaining a stronger SEI layer, but it is most definitely at the cost of a lower potential battery.

  12. Laptops and Electric Cars by zioncity · · Score: 3, Interesting

    This bodes well for everything that runs on batteries that can take advantage of this.. with some exceptions like Lead Acid batteries of cars and such. Just think.... my iBook and Powerbook laptops last much longer on a fresh battery than a comparably equipped Intel Mobile Pentium based laptop or even more energy conservative chips... point being... the 5 hours my iBook can get could be well past 10 with intensive use and energry saving stuff set to a minimum. This will bode well for all. Now my PCs can run over 2-3 hours max of use when not using a DVD. Whoo hoo. Plus maybe now electric cars can get a full 300-500 miles of city driving or such, and hybrids will benefit as for smaller batteries with a similar range/capacity. Now if improvements in technology like this could spur other improvements to make life easier and more affordable for all.

  13. Charge capacity? by stanleypane · · Score: 5, Interesting

    Given the current state of battery life, I'm inclined to think this technology might bring along other trade-offs. Current Lithium batteries tend to lose their full charge capacity after using them for a while. If these batteries charge faster and retain more power, what's to stop them from losing that capacity just as quickly?

    Personally, I'd be happy not having to replace a battery because it becomes useless after a while. They aren't cheap, and they lose their life too quickly. I guess 2 out of 3 wouldn't be bad, though.

  14. Read the article? by jsimon12 · · Score: 3, Insightful

    As long as this is NOT some sticker that creates a magnetic flux in the battery via the Hotzman effect, then I will be willing to say it might not be snakeoil.

    Read and judge for yourself

  15. Hard hat required by bo0ork · · Score: 3, Informative
    Assume your laptop has 4000 mAh (or 4 Ah). Triple that is 12 Ah. If my old memory serves, recharging 12Ah in 5 minutes would then require 144 ampere.

    They should add a warning label: "May require personal nuclear reactor, shrapnel shields and additional fire insurance payments."

    --
    Does everything include nothing?
    1. Re:Hard hat required by pong · · Score: 5, Informative

      My laptop battery has a voltage rating of 10.8. The amount of energy in Joules on a battery with a voltage of 10.8V and power rating of 12Ah, would be

      E = 10.8V * 12Ah = 129.6Wh = 467 KJ (3600 J/Wh)

      E = P * t, so P = E / t

      P = 467 KJ / (5 * 60) secs = 1555W

      1555W is less than many hair driers

  16. Skewed? by Dausha · · Score: 3, Insightful

    "Anyone else think snake oil?"

    Doesn't that sort of skew perceptions a bit much? I mean, leave we dotters to trash the article, the company, the product and explain why if it ran Linux the world would be a better place. But to come right out and abjectly claim snake oil seems a bit much to me.

    Next, you'll be telling me that you can't fit a GB of data on a 1 in. HHD, or that the Flood is not visiting SoCal (the Biblical Flood, not Halo2).

    Assuming you're right with the snake oil. At least they're only hurting stock holders and not the Open Source community by suing IBM. Stock holders by the nature of buying stock assume the risk. If this is a press release to induce a pump-and-dump, as seems to be hinted, then the SEC will be looking for them.

    But, if they can get faster charging, higher capacity battries, then maybe my laptop can weigh less. I mean, if most car's MPG and tank capacity give them roughly 300 miles of range, why should the industry let you get away with using your laptop unplugged for more than 2 hours?

    --
    What those who want activist courts fear is rule by the people.
    1. Re:Skewed? by imsabbel · · Score: 3, Insightful

      Well, if in a field where a lot of research is done, showing a history of small gradual improvements, one company starts claiming a factor 3 increase out of nowhere, such a comment is valid.

      --
      HI O WISE PRINCE. WHT TOOK U SO DAM LONG?
  17. Re:Seems about due by scubaed · · Score: 4, Informative

    For those that don't want to take the time to look at the article (and before it gets /.'ed), here is the meat:

    "The nanomaterials Altair is developing are the next generation of electrode materials for lithium-ion batteries and Altair's research and product development is laying the ground work for a new generation of ultra high power lithium ion batteries." commented Dr. K. M. Abraham. "A key requirement to the above applications is the ability to recharge the battery very quickly, for example in a few minutes. Current Li Ion batteries are incapable of such quick charge times because of the chemistry of the anode materials. Altair has found a solution to this with their nano-sized lithium titanium oxide."

    "Altair's nanomaterials, which have a virtually zero strain crystal lattice, eliminate the main cause for battery electrode material fatigue, which limits rechargeable battery life, increasing the number of recharge and discharge cycles from a few hundred to many thousand cycles," said Dr. Vassilis G. Keramidas. "I find Altair's development strategy and proposed research direction sound and a necessary step in establishing the Li-Ion electrochemistry as a viable contender for large battery applications."

    Sounds promising (though if I hear the nano prefix again it'll make me barf). So no, it's not a new way to recharge batteries Li-Ion batteries, it's new batteries that can be recharged faster.

    Let's hope that they can manage the lawsuits after the first batch starts to catch fire.

  18. Article on Yahoo by Anonymous Coward · · Score: 4, Informative

    More detail and not yet Slashdotted; http://biz.yahoo.com/iw/050210/080729.html

  19. No, it's the ISD that will get them, by MarkusQ · · Score: 3, Interesting

    The real problem with new fangled almost-magic batteries is going to be the liability from ISD (Instantanious Spontanious Discharge). I've seen a video of a test with a lab rat, and all I can say is you'll want to keep these things out of reach of rodents! (And that I'm glad I wasn't there to watch it in person!)

    --MarkusQ

  20. Not a Hype by Compile+'em+all · · Score: 4, Informative

    The site is already down. And it doesn't look like another hype(at least to me). It seems that those guys have actually done something. Read on :

    RENO, NV--(MARKET WIRE)--Feb 10, 2005 -- Altair Nanotechnologies, Inc. (NasdaqSC:ALTI - News) announced today that it has achieved a breakthrough in Lithium Ion battery electrode materials, which will enable a new generation of rechargeable battery to be introduced into the marketplace, as well as create new markets for rechargeable batteries. These new materials allow rechargeable batteries to be manufactured that have three times the power of existing Lithium Ion batteries at the same price and with recharge times measured in a few minutes rather than hours.

    The technical achievements are being praised by the battery community as truly remarkable and will likely enable a new generation of rechargeable battery to be produced. Altair has confidentiality agreements in place with some of the world's leading battery development companies to evaluate and commercialize these battery electrode materials.

    Altair's research and development efforts were allowed two new patents (announced on January 7th and 14th, 2005) and a National Science Foundation grant was successfully completed in January, 2005, by Altair. New markets for fast charging batteries will include the handheld power tools market increasing the productivity of, for example, construction workers while lowering their overhead costs. Other markets include hybrid electric vehicles, portable electronics and medical surgery tools -- solving the problem of electrical wires all over the operating room floor.

    Rest of article can be found here
    http://biz.yahoo.com/iw/050210/080729.html

  21. Re:sweet! by kevinx · · Score: 5, Funny

    It's those inconsiderate jerks who read the article before they post. Now all of us who posted first can't read it.

  22. Re:Yes, by RadioTV · · Score: 3, Insightful

    What does the density of transistors on a die have to do with battery power? Why is it that people who don't have any idea what Moore's law actually says think that they can use it anywhere they want. I saw a sign for two fish sandwiches for $4. Does that mean that Moore's Law has caught up with the fish sandwich?

    --
    I have great faith in fools - self confidence my friends call it. - Edgar Allan Poe
  23. 300~% more power is good, but I want more capacity by DFJA · · Score: 4, Interesting

    Can't RTFA because it's /.ed, but it looks to me like they have increased the power capability by increasing the surface area within a given volume so that it can produce a larger current, much in the same way that the lungs can produce a large exchange of O2 and CO2 due to their large surface area.

    This has nothing to do with capacity, which presumably is unchanged from more conventional technology.

    Not a bad thing in itself of course, if it expands the market for which LiIon is suitable.

    --
    43 - For those who require slightly more than the answer to life, the universe and everything.
  24. I think your math is wrong... by DarkMan · · Score: 5, Insightful

    I don't belive that the claim is that thier new batteries have three times the capacity of a current Li-ion battery. They are claiming three times the power, which I read as meaning that the peak discharge power is three times greater.

    This is a lot more reasonable, from my understanding of Li-ion batteries. The theoretical energy capacity isn't three times current batteries, IIRC, so trippling that is unreasonable. But three times the discharge rate is not impossible, and brings them into the range of NiMH batteries, maybe even Lead-Acid. Coupled with the superior energy density of Li-ion, that's very very nice.

    This matches well with the claim of faster charging - the limiting factors for charging and dischargeing are related in batteries.

    So, your sums become 4Ah in 5 minutes, or a much more reasonable 48 amps. A lot, yes, but not beyond what's currently done with medium current applications.

    Reading the press relase as I did above imedialty makes is much more reasonable, although I'd love to get more details. There's a lot hingeing on the word 'power', depending whether you read it in a technical or common definition, so much so that I wouldn't want to depend on it.

  25. 3x max current, not capacity by fhage · · Score: 5, Informative
    According to http://www.evworld.com/view.cfm?section=communique &newsid=7681 "The nanomaterials Altair is developing are the next generation of electrode materials for lithium-ion batteries and Altair's research and product development is laying the ground work for a new generation of ultra high power lithium ion batteries," commented Dr. K. M. Abraham. "A key requirement to the above applications is the ability to recharge the battery very quickly, for example in a few minutes. Current Li Ion batteries are incapable of such quick charge times because of the chemistry of the anode materials. Altair has found a solution to this with their nano-sized lithium titanium oxide."

    Current Li batteries are very limited in their max current. This make them poor choices for high current applications, like electric motors. It won't make your laptop run any longer, but you'll be able to charge it 3x faster.

  26. "Two eminent experts' by exp(pi*sqrt(163)) · · Score: 4, Insightful

    Nobody writes a phrase like that unless they're bogus. That's the kind of language you get in endorsements for the latest diet fad or transcendental meditation technique.

    --
    Doesn't it make you feel good to know that our freedoms are protected by politicans, lawyers and journalists.
  27. Power vs. Capacity by mike449 · · Score: 4, Interesting

    They carefully avoid the word "capacity" in the press release. This and the claim about faster charge makes me think that they somehow managed to reduce the internal resistance of the battery, but the capacity (measured in Ampere-hours) hasn't changed.
    "3 times the power" probably means that the battery can yield 3 times higher current when discharged into a short circuit (before exploding). But the energy storage capacity is the same. I believe that battery technology is already pretty close to the theoretical limit here.

    This new development may allow to replace NiCd batteries in very high current applications, which is good.

  28. when to sell? by Sean+Clifford · · Score: 4, Informative
    The only question is... do you dump the stock before the conference call, or do you expect the hype to endure?

    Disclaimer: This is not investment advice, but my own personal opinion. I am not a financial advisor, I'm just an IT geek and web developer.

    My two cents:

    I'd sell before the conference call. In this case I would have already doubled my stake, it would be time for me to cash out. Stock is not money.

    It's very very hard not to get caught up in the moment. I'd rather miss the next Google than suffer an Enron. If I'm going to speculate again, I'll do it wisely.

    My rules:

    Stick to your guns - if you're up by X percentage, sell. If you're down by Y percentage, sell.

    Never, ever, *EVER* day trade with money you cannot afford to lose. Under *no circumstances* do you ever put all of your money into a single stock. Or even a single industry. Doing any of these is roulette, not speculative investment.

    My personal opinion is that it's better to go with a stock market index fund and invest for the long term than it is to day trade. If long term investment is good enough for Warren Buffett, it's good enough for me. I don't have his savvy; hence an index fund.

  29. Re:Seems about due by fearofcarpet · · Score: 5, Interesting

    This all sounds like BS to me. Our lab is part of a nation-wide program to develop new battery technologies and I have no idea why they claim lattice strain as the main cause for eletrode fatigue... The problem with ANY battery is that ions have to move as the battery is charged/discharged. These ions are all lithium in lithium-ion batteries (AKA lithium rocking chair or rocker batteries). The material between the electrode compartments has to be a insulator able to transport Li+ reliably. Since liquids in batteries are not such a good thing they use various gel mixtures for this medium (and the rate of ion diffusion is inversly related to viscosity). Every charge/discharge cycle more an more ions get stuck and hence lower the capacity of the battery over time.

    The "problem" electrode as far as I know is actually the graphite (like the stuff in pencils) end which get's reduced and forms a lithium salt. When you hook up battery the graphite re-oxidizes, sending the electrons through the circuit and Li+ through the insulating medium. Most "nanomaterials" focus on increasing the surface area of this electrode to allow for more efficient (and rapid) charge storage/discharge. At the other electrode is some (probably cystalline) inorganic oxidant which does break down over time. My guess is that they just found some new inorganic electrode material that is slightly better and they, like EVERY other lab, are claiming they've "solved" the Li-ion battery problem. I've seen way too many talks from people claiming essentially the same thing to put my grains of salt away just yet.

    But hey, I'm not on the nanobattery (did you barf?) project and am by no means an expert, so someone please correct me if I'm wrong... FYI "nano" makes me want to puke too. Every week there is some jack-ass giving a talk about "nanomaterials" that are MICROns in size and characterized with MICROscopy. In chemistry land (where I live) a nanometer might as well be a mile (except electrons tunnel more frequently) 'cause atoms are really freaking tiny and that's what we've been using to build our materials for over 200 years : )

    --
    Actually, I wrote my thesis on life experience.
  30. Is it really 3 times the power? by grahamsz · · Score: 5, Informative

    If so then it's only going to allow power to flow out of the battery 3 times faster, allowing a whole new generation of power-hungry athalon laptops (at 1/3rd of the current battery life)

    However if it were 3 times the ENERGY then it'd make existing laptops run for 3 times longer.

  31. Re:Seems about due by reverseengineer · · Score: 3, Informative
    From this page:

    The successful utilization of a carbon host to store lithium ions in the rechargeable negative electrode has led to the commercial development of lithium-ion cells. In commercial cells, the positive electrode is primarily a lithiated metal oxide, which also contains graphite to improve the electronic conductivity of the electrode.

    The electrochemical reaction at the negative electrode in lithium-ion cells is the intercalation of lithium ions into graphite: the lithium ions in the electrolyte enter the space between the layer planes of graphite during charge. The distance between the graphite layer planes expands by about 10% to accommodate the lithium ions. The resulting material can be chemically represented as LixC6. When the cell is discharged, the lithium ions are removed from the graphite structure and return to the electrolyte. The maximum amount of lithium ions that is stored in graphite is equivalent to x = 1 (LiC6). Other carbons have been used which yield values of "x" that may be greater or less than one. One of the attractive features of this electrode is long cycle life that is observed when the reversible insertion and removal of lithium ions occur without mechanical degradation of the graphite structure. Currently, lithium-ion technology represents the most rapidly growing (in production volume) rechargeable battery system in the world.

    So, it doesn't appear to be a true ionic salt, in the sense that something like lithium chloride would be. This sort of intercalation is a good demonstration of how while "chemical bond" usually conjures up an image of solid spheres connected by a rod, like in those plastic model sets, in actuality a bond can be delocalized. In particular, there is a fascinating group of substances known as the metallocenes which feature a metal ion sandwiched between planar carbon rings. Not bonded to a carbon, but instead complexed with the entire aromatic ring structure. Graphite consists of planes of these carbon ring systems fused together to form a planar sheet (graphene). While strong covalent bonds hold carbon atoms in a graphene plane together, far weaker forces hold the planes together, so that lithium ions can squeeze in between and take up residence. As such, lithium ion batteries are quite different from, say alkaline batteries in that rather than the production of current by a reduction/oxidation reaction between a pair of substances. In Li-ion batteries, the potential is provided by lithium ions themselves shuttling out of the graphite lattice- as the grandparent noted, they are sometimes referred to as "rocker" or "swing" batteries because of the back-and-forth movement of Li ions through use and recharge cycles.

    In general, carbon has some rather limited and screwy ionic chemistry, owing to its place on the periodic table- there's a distinct preference for covalent rather than ionic bonding - even carbon halides are generally considered covalent. Carbocations and carbanions are both important species in organic chemistry reactions, but in most cases are not very stable- they tend to be transition states that end up as an uncharged final product. There are of course many known organic ion compounds- acetate ion, from acetic acid (vinegar) is a familar example- but generally it ends up being other atoms in the compound, usually oxygen or nitrogen, which can actually be said to carry the charge most of the time. Even in organometallic compounds, generally the metal-carbon bond has covalent character- there are some important exceptions though, usually brought about using very strong nonaqueous bases like sodium amide. Even "carbide" compounds are generally network solids, which is to say, covalent. Calcium carbide, CaC2, might qualify, though if you try to dissolve it in water, you do not get carbide ions in solution, but rather acetylene gas. You can of course make ionic compounds out of any element- just provide the

    --
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  32. Re:Some hard facts by serbanp · · Score: 4, Informative

    Fully agree with the parent poster. These guys just wanted to pump-up their stock price with BS statements. It looks they've been successful at that.

    Not only they blurr the line intentionally between power and capacity, but also they liberally use the nano-* buzzword.

    A three-fold increase in the battery capacity would be an enormous advancement. LiIon is already the highest energy-density type of battery, so it would matter a lot.

    Maybe they merely found a way in decreasing the internal resistance; advanced LiPoly batteries already do this and there are 2000mAh types rated at 15-20 C discharge rate.

    Charging them, however, still requires no more than 2 C. Chemistry has its own reaction rate and no amount of snake-oil will speed it up.

    If this thingie has any value, it may be for miniature batteries, but don't hold your breath.