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Power Hardware Science

Video Shows Why Recharging Kills Batteries 111

Posted by timothy from the batteries-all-suck dept.
sciencehabit writes with this except from Science: "You may not give a lot of thought to what happens inside the battery of your laptop or cell phone, but to judge from this video, it's not a dull place. The battery in question is a miniature rechargeable lithium-ion device, and the clip shows what happens when it is charged. As lithium ions flow from the positively charged cathode into the 200-nanometre diameter wires of tin oxide that make up the negatively charged anode, the nanowires writhe and bulge, causing them to expand up to 2.5 fold. The wires also change structure from a neatly ordered crystal to a disordered glassy material. These distortions may explain why such batteries ultimately wear down. Knowing more about the process may help researchers develop longer lasting, and perhaps much smaller, batteries in the future."
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Video Shows Why Recharging Kills Batteries More

Video Shows Why Recharging Kills Batteries

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  • Probably easier said than done, though. I believe these don't alter their structures but merely support a larger or smaller buzz of electrons. Any +5 insightful candidate to comment on that?

    • Re: (Score:2)

      by eexaa ( 1252378 )

      Not that it wouldn't be offtopic, but...

      Some guy was developing a theory that actual money we have now can be replaced by energy, when it can be properly easily stored for use.
      Supercapacitators provide the way to do this.

      I'd be happy to finally pay with real resources.

      • Sure, then someone would finally come up with a working fusion reactor and wham! Inflation makes all your "energy money" useless.

      • Re: (Score:3, Insightful)

        by Anonymous Coward

        Wouldn't it be just the same system we use now, except backed by electrons (instead of fiat, or metals)?

        I can't see our physical money tokens being replaced by batteries - not unless either the storage density goes up a few orders of magnitude or power prices do, and that's not counting the price of the battery itself. Power is about 10 cents per kilowatt hour. My laptop battery is, what, 60 watt hours? Even if it was 600 watt hours in the same volume and weight, that's worth less than ten cents.

      • Carrying around compact energy devices instead of cash. What an idea! Think how dangerous Bill Gates's wallet might be (I was going to write 'Warren Buffett' and then thought he doesn't seem to spend much money.) You wouldn't want to be in the vicinity of an uncontained wallet failure. Bang! It's raining pennies from Heaven...
    • I'm a +5 insightful CANDIDATE, but no one seems to vote for me. I think the title was VERY misleading in saying that there is a video showing why recharging kills batteries when in fact it's just a hypothesis. no need to say welcome to /., I already know. :P

    • A super capacitor is basically a highly convoluted labarynth of activated carbon, submerged in an electrolyte solution.

      It works by radically increasing the surface area of the interface layer, where the electrical charge potential gets stored. More surface area==More theoretical maximum charge.

      An electron micrograph of the kind of activated carbon in question [utdallas.edu] is really all you need to see to understand just how much surface area you are talking here by using the activated carbon instead of the more traditi [ami.ac.uk]

  • You got all that from THAT video? (Score:5, Funny)

    by Monkeedude1212 ( 1560403 ) on Thursday December 09, 2010 @05:34PM (#34507010) Journal

    I keep watching it over and over again, in its 17 second glory... and I honestly wish I could believe you.

    No, I'm almost positive (no pun intended) that this is actually a Rorschach inkblot VIDEO. You see whatever your subconscious is thinking about. Edwin Cartlidge is obviously suffering from the stress of a bad phone lithium ion battery - and when he stumbled across this video thats what he percieved is happening.

    For me, I think this is the opening bit to a Frank Miller or James Bond Flick - I can almost hear the rock/Jazz music chime in.

    What about you guys? What do YOU see?

    • It made me thing of Eraserhead. what does that say about me Doc?
    • Close up of a drop of pond water.

    • Re: (Score:1)

      by f3rret ( 1776822 )

      I highly doubt that the video was the only data gathered in this particular experiment. It's just that it's hard to make a "snappy" video out of pages and pages of numerical data gathered from whatever else they were using to gather data from the experiment.

    • Re: (Score:2)

      by eepok ( 545733 )

      FTFA JUST below the video: As lithium ions flow from the positively charged cathode into the 200-nanometre diameter wires of tin oxide that make up the negatively charged anode, the nanowires writhe and bulge, causing them to expand up to 2.5 fold. The wires also change structure from a neatly ordered crystal to a disordered glassy material. These distortions may explain why such batteries ultimately wear down, the team reports online today in Science.

    • Re: (Score:1)

      by Anonymous Coward

      I'm almost positive (no pun intended) that this is actually a Rorschach inkblot VIDEO.

      Rorschach? Isn't he the guy who drew all those pictures of dead hookers?

      • Rorschach? Isn't he the guy who drew all those pictures of dead hookers?

        Ah, I see why you are posting anonymously.

    • [..] that this is actually a Rorschach inkblot VIDEO

      You mean like these pornographic ink drawings of naked women?

    • I see a digestive track gurgling.

      I must be hungry.

    • I don't see anything. No video to be found. I allowed most of the scripts on the page, but google-analytics is on my blacklist. Perhaps it needs to be enabled to watch the video? No idea.

      So what do I see? I see a site that runs a shitton of sketchy-ass scripts, and doesn't work without them.
      • Re: your sig.

        Try Digg.

        After a few days there, slashdot comments will look like extracts from "The World's Greatest Wits and Philosophers" by comparison.

    • "These distortions may explain why such batteries ultimately wear down. Knowing more about the process may help researchers develop longer lasting, and perhaps much smaller, batteries in the future."

      Perhaps I'm slow but wouldn't battery companies and researchers already know this given the rather long time these batteries have been around?

      It seems akin to saying, to use the car analogy, "See how this oil breaks down over time and doesn't lubricate as well, studying this researchers may find out ways to extend engine life."

      What am I missing?

  • For my fellow noscript and requestpolicy users... (Score:5, Informative)

    by TheCarp ( 96830 ) <sjc.carpanet@net> on Thursday December 09, 2010 @05:40PM (#34507074) Homepage

    The sight has a boatload of requests going all over the place... the video is hosted on "brightcove"

    • The sight has a boatload of requests going all over the place... the video is hosted on "brightcove"

      Thanks!

      • Thanks, but that's not even an option for me. I apparently have to enable some other script to get that one... Yet another site which loses my eyeballs due to its sketchy-ass maze of scripts.

    • So does the site, from what I've seen.

  • What we don't know why or how? (Score:4, Interesting)

    by Twinbee ( 767046 ) on Thursday December 09, 2010 @05:43PM (#34507134)
    I find it pretty amazing that we don't really still understand why these things wear out. It's a bit more forgivable for something like the human brain which is much more complicated, and where we can't easily poke around for obvious reasons.

    But batteries?

    I'm guessing our tools to get a peak of the microscopic realm must still be in their early stages technogically.

    • Re:What we don't know why or how? (Score:5, Interesting)

      by jeffmeden ( 135043 ) on Thursday December 09, 2010 @05:56PM (#34507258) Homepage Journal

      We do know why, and it's simple; parts of the insides of the battery end up in different places over time. The chemical reactions that take place during charging and discharging don't happen with perfect symmetry in forward and reverse, therefore each cycle will leave a little less reactive material than before. Making a battery with such perfect symmetry might be theoretically possible but it's not been achieved with any cost-beneficial success.

      The bottom line is that batteries, like many other things, are only gradually improved since the process of production that establishes their characteristics can only be gradually improved. The lithium-ion system was a LONG time coming from the days of lead and nickel, but nevertheless it's just another stop on the road to better things.

      • Re: (Score:1)

        by Anonymous Coward

        There are actually many batteries that are durable through a vast number of cycles. Nickel-hydrogen batteries last for around 20,000 charge cycles (if you charge it once a day, that's over 50 years) and nickel-iron batteries last basically forever.

        The advantage of lithium-ion batteries is their high energy density, but they are still far inferior to nickel-iron batteries when it comes to durability.

      • Re: (Score:2)

        by stdarg ( 456557 )

        I wonder if the technology from that story on self-healing solar cells would help with batteries.

    • Re:What we don't know why or how? (Score:4, Interesting)

      by koolguy442 ( 888336 ) on Thursday December 09, 2010 @06:53PM (#34507858)

      TEM Comments
      This experiment was actually quite a bit harder to carry out than you think. (I imagine, as I wasn't involved in this study but do similar work.) Doing these experiments is like traveling to the moon in that the principles are relatively simple, but it's the details that are hard. While operation of the TEM is relatively easy, preparation of samples is extremely tedious even when the sample is relatively robust and isotropic and it doesn't matter where you need to look on the sample. Constructing a TEM specimen with the intention of looking at a tiny little feature of some larger piece of material is extremely difficult, taking hours or days, if even possible. It's even more difficult to prepare a specimen and have the right equipment set up to control and observe dynamic processes, such as lithium discharge from a single nanofiber. And viewing dynamics in a complicated system, like a battery, which contains at a very minimum three active components, anode, cathode, and electrolyte, is another order of magnitude harder. Plus you have to find a way to make the thing less than 20 nanometers thick and get it into a microscope at high vacuum without breaking or contaminating it, which is nontrivial. There's also the cost of the equipment, which is between $500,000 and $10 million for the microscope itself and another couple hundred thousand dollars for the specialized probes required to do this experiment. I do this for a living myself, as do many people across the world who are either pursuing or already have PhDs in microscopy and analysis, and if it were easy, it'd've already been done and we'd be out of the job.

      Battery comments
      We understand pretty much exactly why batteries wear out. Though the anodes in "real" batteries are usually some form of graphite, which expands less than 10% versus the SnOx in the video (~250%), there is still jostling of all the little powders that form the battery upon charging and discharging that eventually lead to the individual particles separating from the electrodes as a whole and essentially becoming dead micro-paperweights within the battery cell. It's just very hard to image them dynamically in a realistic operation because air and water vapor tend to destroy the materials nearly instantly.

    • Don't know if anyone cares but during the 90s, when Toyota & Honda were developing their Hybrids, they discovered batteries could last near-forever if kept betweens 50% and 80% state-of-charge.

      If charged to full or depleted, then the stress would cause internal damage to the cells, but by keeping them in that "sweet spot" the batteries lasted 200,000 miles of drive time w/o almost no measurable loss in capacity.

      • Re: (Score:1)

        by Nadaka ( 224565 )

        Great, that means they are only 2 times larger and heavier than using batteries in the normal way.

        • What's cheaper?

          A slightly-more expensive 2x battery that lasts the life of the vehicle and never needs replaced? Or a 1x battery that has to be replaced every 75,000 miles at ~$4000 a pop (plus labor)??? I think Toyota/Honda chose wisely when they decided to make the battery last the life of the car, rather than sock customers with expensive replacement costs.
          .

          >>>if you're only allowed to use 30% of that capacity isn't that just as bad?

          Well considering Toyota's first hybrid (prius) got 50-60 MPG

      • Re: (Score:2)

        by dpilot ( 134227 )

        I've heard something like that, and that the hybrids on the road today operate in that sweet spot. But it makes me wonder what's going to happen to the batteries of those people who buy the plug-in kit for the Prius, and presumably deep cycle regularly. BTW, I believe current cars run on NiMH. (Is the Volt the first Li battery car?)

      • Maybe there's no loss of capacity, but if you're only allowed to use 30% of that capacity isn't that just as bad?

      • If you only use 30% of the capacity of the lithium battery... you might as well just save your money and buy long life lead acid batteries instead. They will end up being the same size/weight and with the money you can buy three sets that will get you way past 200,000 miles of life.

    • Have you considered that the people reporting on this aren't well-informed om what is known about batteries?

      • Re: (Score:2)

        by Twinbee ( 767046 )
        That did cross my mind. I have heard it elsewhere, but I expected better from the Slashdot editors.

        (yes, that last bit was a joke).

  • The usual cure for material fatigue

    • Sure, they'll just need to develop the rest of the battery so it can survive temperatures above 300C for extended periods.

  • I thought, Anode is positively charged and Cathode is negatively charged, in my whole life... Is this a typo? Or is this because positive and negative are entirely our convention and it depends on where we observe them from?

    • Re: (Score:1, Flamebait)

      by BitHive ( 578094 )

      no you were just wrong

    • Re: (Score:1)

      by Anonymous Coward

      I thought, Anode is positively charged and Cathode is negatively charged, in my whole life... Is this a typo? Or is this because positive and negative are entirely our convention and it depends on where we observe them from?

      You and the article are both correct. It's just that while recharging the battery, you need flip the direction of the current, which means the charges get reversed.

    • Re:Positive and negative? (Score:5, Informative)

      by cdrudge ( 68377 ) on Thursday December 09, 2010 @06:06PM (#34507366) Homepage

      It depends on if the battery is charging or discharging as to if the anode or cathode is the positive or negative terminal. Read the top of the wiki page for cathod [wikipedia.org] or anode [wikipedia.org] for more info.

    • Re: (Score:2)

      by snookums ( 48954 )

      The anode is where oxidation happens, the cathode where reduction happens.

      Then recall the OILRIG. Reduction is loss (of electrons), oxidation is gain (of electrons).

      In the normal operation (discharge) of a cell, reduction is going on at the cathode, "sucking out" electrons, if you will, leaving a positive electrical potential. Thus, in normal operation the cathode is the cell/battery terminal marked +. The reverse is happening at the anode, which thus is the terminal marked -.

      During charging, you're pumping

      • Re: (Score:1)

        by Anonymous Coward

        Care to explain OILRIG further?

        You claim:

        Reduction is loss and Oxidation is gain, but if OILRIG is an acronym, is would stand for:

        Oxidation Is Loss (OIL) and Reduction Is Gain (RIG).

        thx

        • Re: (Score:2)

          by snookums ( 48954 )

          Sorry, the mnemonic works as you have it written. I had it the wrong way around.

          At the cathode of a discharging battery cell, the chemical in the cell is being reduced and is thus gaining electrons. These electrons are, in a sense, taken from the electrode leaving it with a positive potential.

      • Re: (Score:1)

        by rdsingh ( 643439 )
        Thank you! Much appreciated reply.

  • It's an engineering trade-off (Score:5, Informative)

    by Anonymous Coward on Thursday December 09, 2010 @05:53PM (#34507232)

    You can have a battery which has almost infinite charge-discharge cycles. (iron-nickel) It will be very large and heavy for the energy it stores and also has quite a large self-discharge.

    If you want a small light battery that stores a large amount of energy, something has to give. In this case battery life suffers. You can make batteries that last a lot longer, they will just be big.

    • While that's true, there are always improvements to be made.

      We don't currently get the maximum amount of energy possible out of a battery that lasts for X amount of recharge cycles and is Y big. There is a limit, but new materials and manufacturing techniques get us closer and closer.

      That is what incremental improvement is all about.

    • Re: (Score:2, Insightful)

      by 19thNervousBreakdown ( 768619 )

      If you want a small light battery that stores a large amount of energy, something has to give.

      Why?

      • Re:It's an engineering trade-off (Score:4, Informative)

        by jeff4747 ( 256583 ) on Thursday December 09, 2010 @07:33PM (#34508358)

        Because no one has found a material for batteries without trade-offs. All currently known chemistries maximize at best two of weight, power density and cell life.

        When someone finds a material that maximizes all 3, then we get that whole 'world-changing-invention' situation.

        • Re: (Score:1)

          by Anonymous Coward

          Weight? Making a battery lighter is easy. It's just that half-size batteries only store half as much energy. It's really the energy density that matters. I don't think "power density" is much of a concern nowadays. However, cost is a big issue that you forgot to mention. An unaffordable battery that maximizes all three of your conditions won't be much of a "world-changing-invention".

        • Its a common engineering pattern.

          The 90s-00s NASA paradigm to go for 'better, faster, cheaper' unmanned missions was usually followed by the half-joke "choose 2 of the 3."

    • Iron-Nickel Innuendo (Score:4, Funny)

      by jdev ( 227251 ) on Thursday December 09, 2010 @06:41PM (#34507712)
      Large, heavy and a lot of self-discharge? Are we talking about batteries still or Slashdot users?

      • Re: (Score:2)

        by adolf ( 21054 )

        Large, heavy and a lot of self-discharge? Are we talking about batteries still or Slashdot users?

        Perhaps we are talking about both batteries and Slashdot users simutaneously [wikipedia.org].

    • Re: (Score:1)

      by tkjtkj ( 577219 )
      " If you want a small light battery that stores a large amount of energy, something has to give. In this case battery life suffers. You can make batteries that last a lot longer, they will just be big. " I could not disagree with you more. In fact, your view about 'required trade-off's in engineering are counter-productive to the field. Sometimes its true, but applying your views as the 'general case' just makes no sense. For example, just what were the 'trade-off's when a new electric switching device

  • Xiao Hua Liu (Score:1, Interesting)

    by Wocka_Wocka ( 1895714 )
    This will probably be modded off topic or the like, but I wanted to just add a random fact. One of the authors of this paper was a post-doc in the same lab as me before he started working at Sandia; we were working on a solar cell material project together.

    The paper regarding lithium intercalation is located here. [sciencemag.org]
  • Posting to undo errant mod.

  • Direct link (Score:5, Informative)

    by qwertyatwork ( 668720 ) on Thursday December 09, 2010 @06:04PM (#34507342)
    http://bcove.me/581iaz9a [bcove.me]

    • Re: (Score:1)

      by Tetch ( 534754 )

      You, Sir, are my hero of the day. I'd read this article with interest (having suffered battery death crap like all the rest of us here), but gave up in despair trying to watch that video.

      As a long-time Noscript user, I wondered whether Brightcove might be involved in all the script nonsense, but their name never appears in the Noscript whitelist candidate menu.

      Your link however, works perfectly - Brightcove appears in the right-click menu, along with ScienceMag - and that's it.

      Hey, ScienceMag .... sort i

  • Yeah, all I can say is it looks ... kinda nasty.

    I'm just glad I don't actually *see* this shit happening (full-blown magnification and all) every time I charge stuff up at my bedside.

    • Mmm, yeah...

      the nanowires writhe and bulge, causing them to expand up to 2.5 fold. The wires also change structure from a neatly ordered crystal to a disordered glassy material

      Rule 34 on that!

  • Of making batteries out of DiLithium instaed of just Lithium?

    • But that's only crystals?

    • Re: (Score:1)

      by mysidia ( 191772 )

      Of making batteries out of DiLithium instaed of just Lithium?

      TriLithium resin based batteries would probably be a better choice, since they could store more energy per unit density between charge cycles

  • I keep wondering about this. Why do laptops not come with a switch to cut off the charge when the battery is, say, 99% full? Is it purposely so that the battery will die faster? The laptop works without a battery (while plugged in) so the regulator obviously is capable of handling both AC and battery levels of voltage.

    So why are they constantly destroying batteries while plugged in?

    • Oh, they certainly exist. I design small consumer electronics devices, some of which have lithium-chemistry batteries. Many of the sub-amp battery charger ICs that I've used (case in point, the Intersil ISL6292) will drop to zero charge current at the end of the charge, when current into the cell drops below a certain threshold for a given voltage. I can't speak to current design practices for laptops, but I'd guess that they do the same. Of course, charging a device that's operating is an entirely diff

    • Re: (Score:2)

      by mysidia ( 191772 )

      I keep wondering about this. Why do laptops not come with a switch to cut off the charge when the battery is, say, 99% full? Is it purposely so that the battery will die faster?

      Lithium ION battery life is maximized, when kept fully charged at all time; the best possible lifetime is achieved if it's never significantly discharged, so adding a switch would be detrimental. Maintaining the battery fully charged at the float voltage while plugged in increases life of the battery.

      The wiring scheme in a lap

    • Re: (Score:1)

      by Anonymous Coward

      It really depends on how well your device was designed. I have an Acer laptop from a couple of years ago. If I use it on battery for a few minutes and plug it back in, Windows will report a status along the lines of "Plugged in, 97%, not charging". It has to hit 95% before it'll top up to 100% again, and this is all without any of Acer's miserable software installed.

      I also have a smartphone from HTC that will not function at all without the battery plugged in. I frequently remove it from the charger to see

    • Re: (Score:2)

      by shird ( 566377 )

      Lenovo Thinkpad's have expensive batteries that allow for fine-grained control of these charging ranges. It can maintain it automatically, or you can set custom thresholds. i.e charge if below x%, stop charging at y%. This allows you to do things like commute back and forth from work without the constant 99% -> 100% charge cycle. Otherwise you lose a bit of charge on your commute and plugin at work/home inducing another cycle.

  • Why we need to go back to tightly wound springs.
  • I didn't know that. It's really weird that they didn't mention this as an option when I called on the tech support line, don't you think? They almost tried to dissuade me from taking my laptop into the store.

  • What's the deal with battery chemistry, anyway?

    I mean, correct me if I'm wrong or if I'm missing information, but the whole idea behind a battery is that there are more electrons in the plate of metal at one end than there are at the other, right? The electrolyte just frees up the electrons and lets them move from one end of the battery to the other. So any fluid which allows a metal to break down and which can transport electrons is doing the job; even potato or lemon juices work.

    So what exactly is so sp

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