Talk:Lithium-ion battery

From Wikipedia, the free encyclopedia

Contents

[edit] Questionable Picture of "Dell laptop burnt by bad Sony lithium-ion battery"

How did the battery get on top of the laptop keyboard and stick there without burning anything else around it? There are no characteristic marks of warped, burnt, or ruptured plastic on the laptop shell. The authenticity of the picture is questionable. It seems to be a simulated fantasy scene and should be noted as such.

[edit] Much Material is Questionable

The manufacturers of Lithium Ion batteries have been reluctant to publish very much in the way of useable information on this battery technology. As a result many websites have sprung up, some with apparently reputable origins, to fill the void of information. Some seem to have published speculative information that has no citable origin. Many seem to just copied this information from the other sites. The remainder have published differing speculations. This article seems to have quoted and cited much of the uncited sources. As a result some of the information is useful, but some of it fails to square with real world Lithium Ion batteries.

For example, someone has stated that Lithium Ion batteries must never be deep discharged. Whilst it is true, they should never be discharged to zero volts, there is nothing to prevent a cell being discharged to 2.8 volts without harm (most implementations enforce a 3.0 volt minimum to provide a margin of error).

Someone (else?) has published a table of %age cell degredation with age and temperature (cited from an apparently respectable source). But real batteries are obviously unaware of these sources because there are numerous examples in the wild that have been regularly fully discharged (to 2.8 to 3.0 volts), stored at around 20 °C and kept fully charged in between times. These batteries are over 12 years old and are fully functional. The data in the article suggests that these batteries would have expired years ago, so something is clearly wrong.

I work in the aerospace industry, and am a user of Lithium Ion batteries in many guises. It is a continuing source of frustration that the battery manufacturers just won't tell you some of the things you need to know with respect to battery useage and life information.

Unless, this speculative data can be properly cited from a proper source like the cell manufacturers themselves, it should be removed or at least moved to a section of the article that makes it clear that the information is speculative and possibly inaccurate.

I B Wright 13:50, 13 December 2006 (UTC)

I tend to agree with you. Nothing is referenced properly. 213.78.42.15 (talk) 22:58, 13 December 2007 (UTC)

[edit] Some Chemistry

Although I agree that the entire article's slant towards the practical use and maintenance of li-ion batteries is very useful, perhaps this article could benefit from some more theory, something along the lines of a explanation of the chemistry behind it all. And perhaps, if there exists one, a diagram depicting an li-ion battery's internal design?

It looks like a chemical equation has been added to the article, but it presently reads as:

Li0.5CoO3 + Li0.5C6 < − − > C6 + LiCoO2

This drops an oxygen into the aether somewhere. Poor oxygen.

According to a site I found [1], a very similar equation is given (replace 'x' with 0.5 and write it with reactants and products exchanged):

LiCoO_2 + C_6 \lrarr Li_{1-x}CoO_2 + C_6Li_x

The charging process would proceed left to right in the form I've given; the discharging process would proceed right to left.

But it would be nice to have a real, honest paper source to dervice this from. Heck, I checked all of the references currently on the Wiki article, and I couldn't find the source for the original equation either. Queer.

  1. Electronics Lab, "How to rebuild a Li-Ion battery pack". http://www.electronics-lab.com/articles/Li_Ion_reconstruct/index.html, Retrieved 2006 April 17

OldMiner 23:24, 17 April 2006 (UTC)

I would like to see some electrons in the formula for the reaction. I am trying to check my understanding of things with a few calculations of the weight of stuff in a battery to provide a certain capacity in amp hours and without knowing how many electrons move around for a certain chemical reaction, the reaction formula is pretty useless. It isn't completely useless, as I can add up the atomic weights and get an idea, but I could be out by a factor of 2 or 3 or whatever if the electons released are numerous for one lot of stuff in the formula. Since batteries are about getting electrons moving, logically the formula would be for releasing one electron unless otherwise stated.

There are actually lots of different chemistries of rechargeable li-ion batteries which are lumped in one in this article, commonly found are: LiFePO4,LiCoO2,LiMn2O4,Li(NiCo)O2 see here: http://www.iloveebikes.com/batteries.html Some of the advantages and disadvantges listed in the article apply just to certain chemistries, also the numbers thrown around are not common across all the chemistry variants. Especially the safety aspects. Various (nanotech-)enhanced cathode materials add to the confusion and variety. I think the article is long overdue for a total overhaul and possibly splitting apart. 194.126.108.2 15:18, 23 April 2007 (UTC)

[edit] High Temperature Charging

I have experienced very high temperature with power socket attached to the notebook (cable come from adaptor) when charging batteries with almost discharged capacity. Is it normal for lithium batteries?

This webpage seems to state that Li-ion cells should not heat up when charging. It sounds like something may be wrong with your charger or your cell. Maybe it would be worth getting someone to have a look at it?

  • Most charger does not apply the ideal method because it is a "slow" way of charging. But it shouldn't be "high temperature"(higher than 40 degrees celcius) as it will risk the battery to catch fire.


"Look at the manufacturing date." Yeah, right. Like they tell you!

The increase in temperature ist most likely not from the battery itself, but from the internal current converter, which converts the current from the AC adaptor to the right current for your battery. --Seidler2547 10:04, 2 February 2006 (UTC)

[edit] Good content to add to this page

  • Picture and explanation of the de facto standard three terminals to the raw battery two terminals explosion/overheating/shortcircuit protection circuit. Explanation on how to charge the battery using both the three terminals and the raw two terminals interface. Also an explanation on how to simulate a three terminal Lithium ion battery when there's no battery would be welcome.
  • Picture of a common Lithium ion battery (possibly from a popular mobile phone).
The two/three-terminal approach is VERY manufacturer specific. Laptop batteries often have 5 or more terminals.
A good guess would be: One terminal is ground, one terminal is the protected battery output, one terminal is the input charge voltage (usually 5 volts). A fourth terminal might be a serial communication indicating battery life.
If you wanted to trick a phone into thinking the battery is there, it might be as simple as ignoring the charge-voltage pin and putting the battery across the other two, or it may be as complicated as using a microcontroller to "talk" on that last pin (depending on its purpose). Of course, you would have to have the equipment to figure the purpose of all of these pins out... this isn't the sort of thing I would recommend to even an intermediate electronics engineer. --Mcmudge 18:54, 20 November 2005 (UTC)
This (more than two terminal) discussion may warrant it's own article, or just it's own section for now. It's more of a battery management topic than it is a battery (stricktly the individule cell) topic. I once dissasembled some 40 1.4Ah 18650 cell phone cells (5parallel 8series) to build a scooter pack. No, they didn't last long as they were undersized for the task, as I expected, sized to deliver crusing power(15A) but not accelleration power(50A). A second set of 96 naked ~1Ah prismatic cells (12p 8s) pack is still working well and delivering 10 miles of range [1]. Anyway, the first 18650 cells came in pairs with the milti-terminal management circuit. The circuit was connected to each pair of cells, as they were originally packaged, and though the phone used them both in series for power the circuit had a center tap, which I can only speculate was there to actively keep the pair in ballance. Other than that the only part of the circuit I can positively identify is a 5A fuse, which seperates the positive battery terminal from the positive pad. The other three terminals all appear to be gounds, though only one of them goes directly to the negative battery terminal. I suspect that these circuits are only half of the charge circuit, the other half residing in the phone/device or charger. --D0li0 12:16, 21 November 2005 (UTC)

[edit] Revert

While 82.32.184.126's edit added a considerable amount of information, it amounted to little more than vandalism and has been reverted as such. I believe it was completely inappropriate for several reasons:

  • It was a copy-paste from a website, and was thus poorly formatted to the point of being unreadable.
  • It lost much of its meaning when taken out context.
  • Its tone was openly hostile towards the Wikipedia community.
  • First-person was used inappropriately. Discussing one's self is basically self-promotion.
  • Most importantly, It is intrinsically impossible for an anonymous author to demonstrate he copied information from a website that was his intellectual property, not someone elses.

Anything that the author's information may have added to the article was more than outweighed by the edit's poor tone, marginal relevance, and likely copyright violation.

--Casito 03:17, 10 Jan 2005 (UTC)

[edit] Casito you're a bloody fool

You complaints / reasons for a revert were...

  • It was a copy-paste from a website, and was thus poorly formatted to the point of being unreadable.

yeah, and I made it extremely clear at the outset what it was, and also made it quite clear that I wouldn't have any problem with any EDITS anyone felt like doing. (why didn't I do it myself at the time? at the time was a 9k gsm connection)

  • It lost much of its meaning when taken out context.

rubbish

  • Its tone was openly hostile towards the Wikipedia community.

now that is nothing less than complete and utter bullshit

  • First-person was used inappropriately. Discussing one's self is basically self-promotion.

mm, it was a copy paste that people were invited to edit.

  • Most importantly, It is intrinsically impossible for an anonymous author to demonstrate he copied information from a website that was his intellectual property, not someone elses.

yeah, look at the site in question (http://www.surfbaud.co.uk/index2.php), just above the bottom of the home page, just above the text that says "Copyright © 2005 Surfbaud. All rights reserved."

you'll find some white font coloured text, a pretty adequate demonstration of my intellectual property.

Casito you want to be king of this topic at the expense of actually adding any relevant and useful data for the benefit of the users you go right ahead, you think the tone of this post is openly hostile? It is, but directed at you personally for acting like a tosser, not at wiki.

You say you're a 22 year old mechanical engineering student, I'm a mid forties bloody well qualified and very experienced engineer, and here you are passing judgement on my knowledge for the benefit of everyone else.

You wanna pass judgement on a shitty bit of page editing (which I explained above was due to a flaky and slow connection at the time, and when I got back ashore I clean forgot about this article till just now) go right ahead and I'll agree with you all the way, which is why I said UP FRONT in the posting please feel free to edit or amend this at will so it fits in better.

  • Tone it down, or you will simply be banned. Dan100 08:22, Jan 26, 2005 (UTC)
    • There is some worth-while information in there, but posting it in that manner was completely inappropiate. If you want to write an encyclopedia article, write in an encyclopedic style Dan100 08:26, Jan 26, 2005 (UTC)

Lose the egos guys... this is Wikipedia, not an IRC channel. There is not need for phrases like "it amounted to little more than vandalism" and "acting like a tosser". (Leigh8959 March 5 2005 5:30pm PST)

[edit] Loss of rechargeability

Does anyone know why Li-ion batteries slowly lose their ability to recharge? I would be interested in a chemical explanation.

This article simply lacks any chemical explanation. -- Toytoy 15:59, May 14, 2005 (UTC)
At full charge the cathode contains several high oxidation state metals that gradually either react (get reduced by reaction) with the electrolyte or lose oxygen. This process causes irreversible reactions that gradually results in the buildup of inactive species at the electrodes. Also overtime the active materials slowly delaminate from the current collectors resulting in less 'active' material involved in the cycling process.
But this process is very, very slow. The quoted 5% a month is way off, perhaps 0.5% or something. Personal tests have shown that these batteries keep charge for a year without trouble, and the millions of laptop and mobile phone users who use them daily is proof that the batteries are solid in the main. The only limit I know of is that the cells start to fail when you recharge them too often, the lower limit being around 300 charges. This is why iPods were having troubles, as they charge every time they are conneted to a PC, and they could be in constant use. 300 charges is under a year in those cases. Djvivnji 09:00, 5 June 2007 (UTC)

[edit] Badly formated additions

Toshiba is licensing the process from Altair the patent holder.

This is a encyclopedia article, not a spec comparison sheet. All we need is the range of capacities available in general, not company specific info. Rmhermen 21:35, Jun 6, 2005 (UTC)
Can's the encyclopedia display information about the progress that has been made through out the development life of this technology? How about this? In particular I'm trying to show the rescent increases in power density.

2003

  • Specific/Volumetric energy density: ~150-200 Wh/kg / ~250-545 Wh/L
  • Specific/Volumetric power density: ~300-798 W/kg

2004

  • Specific/Volumetric energy density: 100 Wh/kg / 250 Wh/L
  • Specific/Volumetric power density: 2000 W/kg

2005

  • Specific/Volumetric energy density: 113 Wh/kg / 250 Wh/L
  • Specific/Volumetric power density: 5654 W/kg

--D0li0 01:43, 7 Jun 2005 (UTC)

First these selected data don't show a state of the art. They are just randomly selected data. Second the Wh/kg data don't show any trend so why list them? Third, you are still using a press release of a possible future battery which is not independently verified for the current data. Rmhermen 23:56, Jun 7, 2005 (UTC)
They do show the potential of the art, which will become the state of the art. No trend? How is 300-800, 2000, and 5600 W/kg not a trend, it seems to me to be a 10 fold increase in power density from 500 to 5000. The Altair posts may have been unverified claims, but once Toshiba licensed and build it's prototypes and tested them this technology became proven, no? Do Toshibas measurement devices somehow differ from those you or I might use to measure these cells? So you're saying we have to wait till they go into mass production and we can test them ourselves? --D0li0 01:13, 8 Jun 2005 (UTC)
IO didn't say that the the W/kg data didn't show a trwend. I said that the Wh/kg don't. I said that the W/kg data appear to suffer from selection bias. Toshiba's claims are unverified. You are quoting a company advertisment for a prototype. No one beside Toshiba has one of these batteries and therefore no one run any independent test and verified or dissproven their data. Companies have a long history of painting pretty pictures of their products more gleamiong and impressive than reality. And don't forget thee difference between Li-Ion and Li-polymer. When this does come to market, it may well be considered a new type of battery. Rmhermen 13:04, Jun 8, 2005 (UTC)
Humm, well I guess I'll wait till they go into production or are otherwise validated. Sorry for being such a pain, I'm just really excited about these cells! How about a link to the Electric_vehicle page? --D0li0 20:15, 8 Jun 2005 (UTC)

[edit] A bunch info and answers to incorporate

If you'd like to write some content, here are some things I know about Li-Ions. A lot of this is already covered, but I'm sure there's plenty of info that can be added. I am an electronics engineer -- I make circuits that directly use, charge and protect lithium ion, lithium polymer, ni-cad and ni-mh cells. Please incorporate this information as you see fit. This information applies to both Lithium-ion and Lithium-polymer batteries.

The reason for performance loss is oxidization. This is created by time, charge, and heat. To prolong the life of your battery, keep it somewhere cool (the refrigerator; not the freezer) at a 40% charge. Buy your batteries when you need them; don't buy a second battery until it is going to be used. In applications where the number of recharges is more important than single-cycle capacity, lithium batteries are never charged more than 80%.

The lithium battery nominal voltage is 3.6 volts; this is the voltage at about a 50% charge, and the battery stays the longest near this voltage as it is being used. The charge voltage is 4.2 volts, and the lowest "allowed" voltage is 2.5 volts, although most electronic equipment cuts it off at 2.9 volts for safety. A lithium-ion cell below 1.5 volts should not be charged with the normal charger.

Lithium ion batteries range from 15 minutes to 4 hours to charge; the shorter the charge time, the fewer charge cycles the battery can handle. Although it is not always best for the battery, it is safe to say that any li-ion can be charged in 1 hour. This is done by applying a current equal to their amp-hour rating; a 2.2-amp-hour lithium-ion would be given no more than 2.2 amps for one hour, or until the battery hits 4.2 volts, whichever comes first. After the charging battery hits 4.2 volts, a "top-off" charge can be accomplished by continuing to provide current as the battery overcomes its internal resistance, as long as the voltage does not exceed 4.2.

Lithium ion batteries, like most others, have some internal resistance. When discharging stops, the battery's voltage may recover. Likewise, when charging stops, the voltage may drop, allowing for further "top-off" charging until the battery maintains 4.2 volts. Lithium-based batteries are unique in their ability to deliver power at very low temperatures, and may soon be a replacement for winter lead-acid batteries. No heat should be produced from a charging battery.

Voltages below 2.9 have the potential to harm a lithium battery. Many protection circuits and chargers will place the battery into a "trickle-charge" state, which charges the battery at 1/10th of the charge rate until the battery reaches 2.9 volts, and then charging resumes as normal.

When shorted, older lithium batteries have the potential to produce pure lithium, which is highly reactive. While Nickel-based batteries can usually take the place of common consumer batteries (like alkaline), lithium batteries are almost always accompanied by at least a minimum protection circuit that prevents overdischarge, overcharge and short-circuit.

Because of weight and cost considerations, several consumer industries, such as remote-controlled aircraft models, often do not use the protection circuit. This has led to huge amounts of property damage from fire, including lost homes and vehicles. Short-circuits are the easiest failure to understand. When shorted, the power of the battery is released at the highest rate that the battery can deliver; all of this energy turns to heat, and eventually to fire. The remainder of the fires are greatly misunderstood:

Series-charging of li-ion batteries is a major problem. In order to charge 3 lithium cells in series, the final voltage across all of the cells should be 12.6. However, this does not guarantee that the voltage for each cell is 4.2. Inconsistency in battery temperature, pressure and manufacture can cause a cell to fall behind while remaining cells will reach full charge sooner... as the charge continues, the fully-charged cells become overcharged. After a few charge cycles like this, one of the cells may be undercharged, while one is at a critical voltage (4.5V or higher); this is when the battery gets hot. Shrink-wrap around the battery can then prevent the electrodes from separating, and provide a storage for pressure until the battery bursts, sending burning electrolyte in all directions.

Laptops fix this problem by actually having 4 individual chargers on board. While the cells are discharged as a whole, each cell is charged independently, to ensure that no one cell goes higher than 4.2 volts.

Lithium ions also have a debated use-it-or-lose-it "memory effect". It is theorized that a battery that is left fully charged for long periods will lose its ability to deliver power quickly, even though the power is present in the battery. This will cause the battery-controlling circuitry to sense that the battery is low because the battery can't keep up with the electronics. Likewise, batteries that are exposed to a high-draw may not hold their full charge as long. A counter-argument to this theory is that, especially in laptops, the warmth and full-charge provided by the laptop simply accelerate the battery's natural deterioration. Laptop users that usually leave their laptop plugged in should discharge their battery to about 40% and leave it out of the laptop until it is needed.

Also, Lithium-ion technology is fading away, while more development is being done with Lithium-polymers. All of these technologies have their oddballs:

Lithium batteries typically allow for a full discharge in 4 minutes, however, there are some that can dump all of their power in as little as 60 seconds. (That means LOTS of power, really quick)

Lithium batteries typically take a minimum of 1 hour to charge. There are a few that take 15 minutes, but Toshiba has recently announced a battery capable of being fully charged in 60 seconds.

There are several types of lithium batteries that have lower peak-charge and nominal voltages; be sure you know your battery's operating voltages before trying to charge or discharge them.

Mcmudge 18:55, 20 November 2005 (UTC)

[edit] Freezer issue

I have read in the article that Li-Ion batteries should not be put in the frezzer, which is most likely a result of having this information copied over from variuos websites. However, I find no practical reason why you shouldn't. Of course, the metallic pins of the battery should be isolated, as ice and condesation water could cause an current flow, that could indeed destroy the battery. I've done this, and put a cell phone battery into a freezer of about -15°C for more than three months (of course, as recommended, at 40% charge). Result: after letting it warm up slowly, it works as if it was new, no loss in capacity noticeable.

Condensation may well provide a discharge path, but ice is an insulator. This is why railway companies have to go to great lengths to remove or melt ice that forms on conductor rails during the winter periods.

Of course, charging and use at these temperatures should be strongly discouraged, but the "do not put into the freezer" point should be removed or rewritten. Seidler2547 10:28, 2 February 2006 (UTC)

And what about the condensed moisture inside battery? When cooling down from room temperature, the dew point goes down as well, so at the end you have water/ice inside the battery - on the contacts, on inside electronics and so on. May this be the reason why not to store batteries at so low temperatures? #jez 89.239.7.2 17:09, 11 November 2007 (UTC)

[edit] Invented by Thomas Edison?

I removed the following text by User:Avé:

Image:Ed_d22m.jpg
Thomas Alva Edison used (and preferred) Li-Ion batteries in his electric vehicles. While powered by Lithium Ion batteries, neither his electric trains that circumnavigated the Menlo Park lab/facility, nor the electric autos gained commercial success, it is worthy to note Henry Ford worked for Edison prior to starting Ford Motor Co.

The Detroit Electric car shown in that 1913 photograph predates commercial Li-ion batteries by almost 80 years. It was available with either lead-acid or nickel-iron batteries, as shown in this advertisement. Nickel-iron batteries were invented by Edison in 1901 and manufactured at the Edison Storage Battery Company.

No he didn't. Edison stole the invention of the Nickel-Iron battery from Jungner who experimented with various combinations of Iron and Nickel before finally developing the Nickel-Cadmium battery in 1899. Jungner found that the Nickel-Iron version was considerably inferior to the Nickel-Cadmium and neither patented it nor developed it further. Both variants were largely unknown in the US until the 1940's allowing Edison to claim to have invented the Nickel-Iron. I B Wright 11:53, 13 December 2006 (UTC)

I was unable to find any sources that suggest Edison invented the Lithium-ion battery. As part of my search, I reviewed all U.S. patents granted to Edison with titles containing variations of the words battery, electrode, or electrolyte. There are 94 such patents. And though I found no description of a device similar to a modern Li-ion battery, I did find references to lithium compounds Edison used in the construction of his nickel-iron batteries. Specifically, Edison discovered he could increase the capacity and longevity of nickel-iron batteries by supplementing the alkaline electrolyte with a small amount of lithium hydroxide. This discovery is presented in the following patent:

  • 876,445 Electrolyte for Alkaline Storage Batteries Use of lithium hydroxide in alkaline electrolytes.
    The increase in capacity of an Edison cell in which lithium hydroxid is used, amounts to about ten per cent., while the increase of the time over which the capacity may be maintained is remarkable, and of the highest commercial importance. (pg 1, ln 46)

I also found five other patents in which Edison describes an alkaline electrolyte containing a small amount of lithium hydroxide:

  • 1,073,107 Storage Battery Construction of small storage batteries.
    partly filled with the electrolyte 4, which consists preferably of a solution of potassium hydroxid in distilled water with a small percentage of lithia. (pg 1, ln 55)
  • 1,167,485 Storage Battery Use of cerium oxide as a cathode material rather than the usual nickel oxide.
    For the electrolyte I prefer to employ a solution of potassium or sodium hydroxid, to which may be added a small percentage of lithium hydroxid (pg 1, ln 86)
  • 1,299,693 Storage Battery Addition of tin oxide to iron cathodes.
    For the electrolyte I prefer to employ a solution of potassium or sodium hydroxid, to which may be added a small percentage of lithium hydroxid (pg 1, ln 92)
    An electrolyte containing lithium hydroxide is also mentioned in claims 18–22 and 28.
  • 1,379,088 Storage Battery High discharge rate batteries for starting the Ford car.
    such electrolyte preferably consisting of a 21% solution of caustic potash containing about 2% by weight of lithium hydroxid. (pg 2, ln 123)
  • 1,377,194 Storage Battery Continuation of 1,379,088.
    …such electrolyte preferably consisting of a 21% solution of caustic potash or a 15% solution of caustic soda, containing about 2% by weight of lithium hydroxid. (pg 4, ln 46)

I also found a patent describing the extraction of potassium and lithium from silicate ore. This suggests Edison used lithium in significant amounts, probably in the manufacture of storage batteries.

Curiously, five of these patents use the word prefer or preferably when describing the use of lithium hydroxide. This wording is mirrored in the Wikipedia text. Perhaps the nickel-iron batteries described in these patents were mistakenly believed to be Li-ion batteries?

I believe the addition of lithium hydroxide as described in patent 876,445 doesn't alter the basic chemistry of the nickel-iron cell. These batteries are nothing like modern Li-ion cells; they're more closely related to NiCds. —Ryanrs 14:58, 6 March 2006 (UTC)

I think that would make a nice section at the Nickel-iron battery article, I've copied it to Talk:Nickel-iron battery#lithium hydroxide electrolyte which could use the attention. --D0li0 11:09, 20 March 2006 (UTC)
The Edison examples are not really Li-Ion batteries but early versions of the Ni-Cd or Ni-Zn (even NiMH) batteries where protons do the charge transport.

[edit] Higher-Capacity Lithium-Ion Batteries

New research which I or someone can add when possible. - RoyBoy 800 16:58, 26 June 2006 (UTC)

I hesitate to edit this myself, but the energy numbers given in the article are way too high for real-world lithium-ion rechargable batteries hitting the streets. 100 Wh/kg typically when being discharged from 3,7 downto the cut-off-voltage would be more realistic, and only 60 - 70 Wh/kg if not discharged below 3,5V (for an extended life). These are the numbers found in some other language Wiki contents and these are also the numbers I could find in science literature. Sure, there is an enourmeous technology progress going on right now, but I think, Wikipedia should not just cite the idealised manufacturers data as this will led to wrong conclusions in regard to the technology. Ideally Wikipedia would differentiate between manufacturers data, science data, and practical data. —Preceding unsigned comment added by 84.63.22.179 (talk) 08:55, 12 September 2007 (UTC)

[edit] Polymers = flourinated?

Does anyone have an opinion on Nakajima, T. and Groult, H., eds. (2005) "Fluorinated Materials for Energy Conversion" Elsevier ISBN 0080444725? 66.201.48.26 08:43, 6 July 2006 (UTC)

[edit] fixing energy numbers

The numbers in the table need to be fixed so that they are correct and consistant with the article. Also, I was wondering why we're measuring energy in watt hours..? Fresheneesz 08:11, 9 July 2006 (UTC)

Battery capacities are always measured in Wh not J by those that use and test them - because this is a convenient unit, especially as the charge is measured in Ah rather than C. Simply multiplying the charge, in Ah, during charge or discharge by the average voltage, in V, gives the energy in Wh. To convert to SI units is also quite simple 1 Wh = 3.6 kJ. Ahw001 06:17, 4 September 2006 (UTC)

[edit] prolonging real-world battery life

For an average joe who wants to prolong the life of their laptop (or mobile phone etc); the article says keeping it at 40% is best; but u obviously can't keep a battery at 40% all the time; otherwise there is no point in having it. So what is needed is a range of optimum use? i have heard 80%-40% .. 80%-20%. eg. (excluding long periods of time when it wont be in use) is it better to keep a battery at 40% and then drain it to 20% when u actualy need to use it, or keep it at 60% and drain it to 40% when u need it. How would u keep a battery from charging fully, without removing it? (this part seems like manufacturers specifically try to get ur battery to ruin itself) and also, from what i can gather there is no way to increase the battery life of a li-ion battery, once it has degraded.. right? ~BB, aug19.

According to Toyota, they designed their hybrids to keep the NiMH batteries between 40-70% to prolong life & avoid replacement. It seems reasonable to think Lithium has a similar property. - Theaveng 15:28, 4 September 2007 (UTC)
The lower state of charge (SOC) in HEV operation is more related to the regen braking function. The lower the SOC, the higher the power the battery can accept during braking. Sure, it does prolong life, because if regenerative power were forced into a battery at high SOC it would cause damage. Lithium ion batteries do age more rapidly at higher voltages (= higher SOC levels) because they are thermodynamically less stable. Storing them at less than about 60% would probably not yield significant benefits. Furthermore, if stored at very low SOC there is a danger of overdischarge because of continued parasitic discharge from the on-board electronics. - BatteryGuy 23:13, 4 September 2007 (UTC)

[edit] Toxicity

I came to the page seeking information about the relative toxicity of this battery chemistry as waste. Nothing found. An addition covering this topic would be welcome.

Seconded. Battery chemistry looks tricky to the non-specialist. "Lead-acid", I can guess the risks; "lithium ion", not so much. Even looking up lithium isn't necessarily going to settle the question: for example, carbon looks friendly enough on paper, but less so when it's in carbon monoxide gas. —Eric S. Smith 15:19, 11 December 2006 (UTC)

[edit] Transwikied to wikibooks

This article has been transwikied to b:Transwiki:Lithium ion battery, where it will be modified for use as a how-to chapter. The how to section(s) may now be deleted. --SB_Johnny | talk 11:43, 4 September 2006 (UTC)

[edit] 720 W / kg claim

Everspring [2] claims to sell their 'Lithium ion Power Battery' for $50 / kg at 720 Wh / kg. I could not find real world use of these after a few hours searching the net so I am now even more suspicous of the claims.

It's probably for use in off-grid systems, such as farms with windmills, etc. --SB_Johnny | talk 11:07, 5 September 2006 (UTC)


[edit] Claim in Electric Vehicle Article

There it says: Lithium batteries have been made safe, can be recharged in minutes instead of hours, and now last longer than the typical vehicle.

Seems to contradict what this article says.

www.teslamotors.com says they are using 4600 lithium ion cells with a fuse at each positive and each negative terminal = 9200 fuses. These are slighty larger than AA size cells. Let's consider an improved (possibly) design: 80 somewhat larger lithiun-ion cells in series. This produces almost 300 volts, which allows a simple, cheap, and tiny charger to plug in the 240 volt ac line. Fusing both terminals of each cell separately seems prudent in event of a bad wreck. Each cell has it's own 2 amp charger, voltage limited at about 4.2 volts. A common 6 volt at 6 amps incandecent light bulb can provide the 2 amps approximately constant current from a 4 volt rms transformer secondary and diodes. A computer stops the charging of each cell several times per hour and leaves that charger off if the terminal voltage exceeds 4.2 volts. This provides about 600 watts of charging for the 200,000 watt battery. This system can run 24/7 if the transformer primary is pluged into a live 120 volt ac outlet. It should run whenever the gasoline motor is running to reduce the probability of any cell falling below 2.8 volts. The 80 bulbs are a very dim idiot light for each of the 80 cells. If the main charger is plugged into 240 volts, twenty or thirty additional amps are supplied to the 200,000 watt battery. When several of the 2 amp chargers have shut down, the 240 volt charger will also be shut down (until all the cells are being charged at about 2 amps) to avoid over charging the 200,000 watt battery. If faster charging is desired, an auto-transformer can boost the 240 volt ac input to 250 volts or a bit more. The 200,000 watt battery weighes 111 kilograms using the bare bones energy density of 1800 watts per kilogram. Using the low number from the text 667 kilograms at 300 watts per kilogram, for 20 seconds. An air cooled battery (or refrigerant cooled battery) can likely weigh 300 kilograms, even with saftey devices and containment in event of a cell explosion. We will need more than 20 seconds if the vehicle is pulling a trailer weighing several tons up a long steep hill. The Tesla roadster battery is 280 amp hours, so it takes(not a hybird)ten hours to charge at an average of 28 amps. Generally we start charging at 50% charge or more, and even big hybirds can use less amp hours. Few homes or small businesses are presently wired to charge much faster than 28 amps average, even though a vehicle size lithium ion battery can likely tolerate a 300 amp charging rate at least briefly. Neil

The reason for the individual cells is purely that the 'A' sized cells are so common, and they all have PTC 'fuses' in them to try to stop thermal runaway. They didn't add the fuses themselves. Pull apart 90% of laptop batteries, drill batteries or any other large battery and you will find arrays of smaller cells.Djvivnji 15:03, 5 June 2007 (UTC)


I had heard that the Toshiba corporation has developed a fast charging battery and circuit system that allows fast charging in minutes and that it may be of some use to the auto sector. It seems promising, provided that the oil companies do not try to take over this technology as well. I think they hold a fair few patents for battery technology for automotive propulsion and will not release them on license - Texaco for example holds the patent (through a subsidiary it bought many years ago) for a battery temperature regulator. 80.195.207.65 13:46, 6 December 2006 (UTC)

[edit] Lithium in Lihium Ion cells

Does anyone know how much lithium (in [g]) a 200 wh/kg cell of 1 kg contains ?

[edit] 0% Li-ion becomes 100%

I gave a 0% Li-ion "dead" battery to a repair shop for about 2 weeks, it can "repair" it to 100% "live" battery. I wonder how they can "renew" it or "repair" it. Can anyone tell me? "Put" it in a freezer? "Charge" it with a "special" charger? "Open" it and "repair" the inside content? 0% to 100% is a real story. What is the real explanation? —The preceding unsigned comment was added by 219.79.188.100 (talk) 21:54, 18 March 2007 (UTC).

Some compaanies will repair the battery by replacing the "dead" cells with new ones. The battery packs, depending upon the type, may end up with cells that have more capacity than the originals, and hence last longer. The process is the same regardless of whether it is a NiMH, Li-ion or whatever battery, as it is easier, and safer, to replace all the cells at once.

[edit] quote: lithium-ion batteries should be charged early and often

http://en.wikipedia.org/wiki/Li-ion#Guidelines_for_prolonging_Li-ion_battery_life

Guidelines for prolonging Li-ion battery life

  • Unlike Ni-Cd batteries, lithium-ion batteries should be charged early and often. However, if they are not used for a longer time, they should be brought to a charge level of around 40%.
  • [ ...... ]


http://en.wikipedia.org/wiki/Li-ion#Storage_temperature_and_charge

  • Storage temperature and charge

|::| According to the table in this paragraph[3]: lower charge means longer battery life. And so If I fully recharge my mobile phone's battery, every one or two days, then I will shorten it's life. Therefore it would be better to only recharge the battery when the phone asks me to. This will take use of the entire safe capacity of the Li-ion battery, but also allows it to be in a low-charged state for some days, expanding it's life-time. (pure logic)

|::| George Valkov 16:58, 26 March 2007 (UTC)

You should let them run down. The internal circuits stop them before they get too low, and you are more limited by the limited number of charges than anything else in reality. Djvivnji 15:06, 5 June 2007 (UTC)

[edit] Battery types

There would be a template to all the rechargable battery types (as happens in other topics).


[edit] Deep Cycling

"Unlike Ni-Cd batteries, lithium-ion batteries should be charged early and often. However, if they are not used for a longer time, they should be brought to a charge level of around 40%. Lithium-ion batteries should never be "deep-cycled" like Ni-Cd batteries.[7]"

I don't understand what deep-cycled means... Maybe a clarification would help =) --Grant M 01:24, 19 June 2007 (UTC)

It's when you drain the battery (by definition, over 80%, but they usually mean it can be discharged 100%) before recharging. If you deep cycle Li-Ion batteries, the internal circuitry that protects the battery won't have enough power and you'll never be able to charge it again. The internal circuitry does its best to reserve some power for it to function, so normal use won't deep charge it. --Wirbelwindヴィルヴェルヴィント (talk) 18:22, 19 June 2007 (UTC)

[edit] Reliability of references

I have begun going through the references cited in this article and formatting them for consistency. However, the reliability of the ones we are citing is outright scary. For starters, we have a citation to a movie review of "Who killed the electric car." Not a review in a magazine or newspaper, just a review on the home page of some guy named Paul (no last name given). Next we have several citations written by Isidor Buchmann. Some of them are on BatteryUniversity.com, and one is on his personal page. Buchmann is CEO of Cadex Electronics Inc., a company which sells battery testers and chargers so he, and his company, have vested interests. The only truly reliable sources I have seen so far are the patent references, and possible the lithium-ion handbook, although this too is published by a battery manufacturer. I don't think we should just delete the sources that are listed as its better for our readers to at least see where we got our information, but I think it does give un-due credibility to the article and perhaps it should contain some sort of warning. I don't know if we have a template about the reliability of sources listed but we could just make a box at the top of the page like some of the templates do. The section above "Much material is questionable" also discusses this matter somewhat. -AndrewBuck 17:51, 17 August 2007 (UTC)

[edit] Japanese expert

According to [4], a Japanese expert has recommended lithium ion polymer batteries be used instead of lithium ion. The reference isn't the best though, they don't even seem to realise lithium ion polymer batteries already exist Nil Einne 10:13, 23 August 2007 (UTC)

[edit] "real world testing"

I've removed the section entitled "real world testing", about car batteries. The section was misnamed (Li-ion batteries have had years of real world testing) and did not seem to fit the NPOV. LachlanA 02:41, 18 September 2007 (UTC)

[edit] "50 million ohms" ???

I haven't gone through the pain of checking when that statement was added (that internal resistance will eventually rise to 50 MOhms), but it appears ridiculously high and was not backed up by some proper source, especially since it was given as an indicative value. Plus, in practice, even two or single-digit figures for internal resistance would be a hindrance to any practical battery, let alone 50 MegaOhms. EpiVictor 19:25, 22 September 2007 (UTC)

It originally said the resistance was 50 million Celsius so I expect it's not valid Kirtai 08:50, 23 September 2007 (UTC)

[edit] Explosive safety devices???

"Li-ion batteries contain safety devices that protect the cells inside from abuse, and, if damaged, can cause the battery to ignite or explode."

A safety device that causes a fire or explosion? Perhaps this is meant to say something else...? --Chriswaterguy talk 18:12, 18 October 2007 (UTC)

[edit] "Controversy"

Is controversy the most appropriate word(s) for the headline of that section? I think something like "Defective batteries" or something would be better. andkore 21:15, 21 October 2007 (UTC)

[edit] Fundamental Point

Are all rechargeable Lithium cells "Lithium Ion"? Some sources seem to define lithium ion as a subset of rechargeable lithium cells, whereas others indicate they are the same thing. I think a definitive statement on this would clear up some ambiguity. Do you think it would be useful to create a comprehensive table of currently availble chemistries, similar to (but maybe not quite as verbose as) the Lithium_battery page? I realise that information from manufacturers can be scarce but even just a listing of the chemistries would be useful. (Namxat 10:14, 26 October 2007 (UTC))

[edit] recharge cycle

what is considered a recharge cycle for lithum batterys? every time you plug it in then that is a charge cycle gone? —Preceding unsigned comment added by 24.218.246.100 (talk) 03:19, 22 November 2007 (UTC)

A 'charge/discharge cycle in this context is a discharge from 100% to 0% charge and then a recharge back to 100% charge. Typically stated as 300-500 cycles. Discharging to 50% charge and then recharging is only half a cycle, thus you can expect 600-1000 half cycles (and so on). 20.133.0.13 (talk) 12:42, 1 February 2008 (UTC)

[edit] Add power/size in Battery specifications?

I realise this can be calculated from the other three, but it would be nice to have this statistic at a glance. What do others think? --Skytopia (talk) 11:58, 16 January 2008 (UTC)

[edit] Link to page selling thinkpad batteries?!?!

The first link in "External Links" is IBM thinkpad t40 battery which is a link to "http://www.power-batteries.net/notebook/ibm/thinkpad-t40-series.html".

I didn't look too deeply, but I'm pretty sure they're more interested in selling people a replacement battery than they are in presenting facts about Lithium Ion Batteries... —Preceding unsigned comment added by Elusiveneutrino (talk • contribs) 09:51, 18 May 2008 (UTC)