Dell and Sony knew about and discuss manufacturing job with Sony - made atomic number 3 - Ion batteries as long as ten months ago , but reserve off on put out a recall until those flaws were clearly linked to ruinous nonstarter causing those batteries to catch fire , a Sony Electronics spokesman say Friday .
Spokesman Rick Clancy said the company had conversations in October 2005 and again in February 2006 . give-and-take were about the problem of small metallic element particles that had contaminate Lithium - Ion shelling cells manufactured by Sony , causing batteries to give out and , in some cases , overheat .
As a outcome of those conversations , Sony made changes to its manufacture process to minimise the mien and size of the particles in its shelling . However , the company did not come back batteries that it think might contain the particles because it was n’t decipherable that they were dangerous , Clancy said .
“ We did n’t have confirmation of incidents [ involve fire ] until relatively recently . We meet reports , but did n’t know if there were environmental state of affairs not relate to the system themselves , ” he said . “ Different measures were taken in February and in October [ 2005 ] to further ensure that there were as few of these particles as possible and that they were as small as potential . ”
On Tuesday , Dell and the U.S. Consumer Product Safety Commission ( CPSC ) announced they would remember 4.1 million Dell laptop computer battery pack , cite a fire risk . The reminiscence deal Dell - branded battery pack that use certain Sony Li - ion stamp battery prison cell sold through July , 2006 . Those batteries were manufactured prior to changes made in February , Clancy sound out .
Dell spokeswoman Anne Camden declined to annotate on the conversations with Sony in October and February , but toldInfoWorldthat Dell was “ confident that the manufacturing process at Sony has been changed to call this issue . Now our focus is drift on the side of caution to ensure no more incident occur . ”
Lithium - Ion batteries are constructed with coated anode and cathode foils separated by thin layers of polymer stuff , said Dan Doughty , manager of the Advanced Power Sources Research and Development Department at Sandia National Laboratory .
“ It looks like a jelly roll . You get a eminent control surface area with thin layers . The thin they go with the separators , the more room there is for the active material , ” Doughty say .
The coated layers are wound up on commercial-grade auto to create the private Li - ion cell , and it ’s at that stage that contamination , such as metallic particles , can get embedded in the battery cadre . The metallic particles advert by Sony and Dell may have been rove off by those commercial machines , he said .
Generally , the polymer separator is very thin — less than 25 micrometer ( one one-millionth of a meter ) thick . If that is punctured by an electrically conductive material , like a metal particle , the barrage fire cell ’s anode and cathode unforesightful circuit , Doughty said .
He say an internal little electric circuit was “ the worst scenario in battery plan , because there ’s nothing you may do to control it , ” he suppose . In contrast , manufacturer have a variety of measuring rod to defend the battery subject matter from external threats , like ambient heat .
base on its conversation with Dell , Sony strengthen and reinforced the protective barriers and facing of their barrage fire cells to treat the danger of metal particles piercing the lining of the cellular telephone , Clancy pronounce .
Dell is describe to have known about incident of laptop overheating , albeit in little identification number , for years . It and CPSC recalled 22,000 laptop batteries in December , 2005 , because of overheat problems . Metal particle contaminant was the cause behind that recall , as well , said Scott Wolfson , a CPSC spokesman .
Those units were sold between October 2004 and October 2005 . Sony correct to characterise the discussion between the companies that took place in October , 2005 , and then again in February , except to say that they were “ specific to particular cells of batteries in battery pack used in Dell notebook , ” Clancy said .
Doughty enunciate Li - ion batteries commonly fail “ benignantly , ” in what researchers call a “ soft little , ” in which a low current track is create within the battery that cause it to fire its energy into the cellular phone . However , if a tumid particle of conductive cloth imbue the separator , tie in the anode and cathode , or a small molecule of conductive stuff manages to find just the right position between the anode and cathode , a “ severe short ” can result in which the battery cadre releases all its energy at once , in what ’s scream “ thermal runaway . ”
The key in situations like that is to prevent the reaction from circularise to other cells in the battery pack , which appears to have happened in the now - famous incident in June in Osaka Japan , he said .
But as manufacturers pack more and more power into the Li - ion batteries , the risk of ruinous loser grows , Doughty said . “ The more energy put into it , if things go bad , you lose the ability to have a graceful loser . ”
Sony says that if its batteries fail , it is usually a benignant short circuit that stop over the battery from working , Clancy say . “ system of rules related issues ” that are unequalled to Dell came into play to induce the fervidness , he said .
“ These Lithium - Ion barrage fire coterie are put together base on specification from the maker , ” he said . The form of the cells in the pack , high temperature environment , battery charging stipulation and proximity to other passion source in the laptop computer all vary from manufacturing business to maker , Clancy said .
Fujitsu , Toshiba and Hewlett - Packard ( HP ) said on Thursday that they use Sony Li - ion battery with their organization , but that the batteries are different from those being recollect by Dell . The ship’s company said they did not see a fervidness risk for customers and did not design on doing a battery recall .
“ We ’ve worked with Sony to place whether the jail cell we used were part of the contaminated batch , ” said HP spokesman Mike Hockey . “ We ’ve not seen any outlet whatsoever . ”
But Doughty say that there ’s no guarantee that the flak job with metallic element particles in the Sony Li - ion cells would be circumscribe to Dell systems . “ I ’m an R&D bozo , but the means I read it , if you ’ve got an automobile part that ’s bad in one vehicle , you supervene upon it in other vehicles as well , ” he said .
The CPSC is in ongoing talks with Sony about its notebook battery beyond its order with Dell , sound out Wolfson .
He declined to say which laptop Maker the fellowship was working with , or to say whether it would do a broader recollection of any Sony batteries with the alloy corpuscle contamination problem .
Still , that leave Sony in a sturdy place . “ They do n’t recognise what cells have it and which do n’t . It could be 1.5 portion per million or 400 percent of that . You ’ve got to do examination to find accurate failure pace , and when the failure pace is that downhearted , you have to essay many , many cell to figure it out , ” or expend chance to determine the potential charge per unit of failure , Doughty say .
The best Sony can do is to enforce strict lineament control when making the batteries , especially around the machines that manufacture the Li - ion batteries to make certain no metal flakes are being cast off . Beyond that , the problem is in the hands of regulators , Doughty say .
“ CSPC has to do a risk of infection - welfare calculation . You may recall the risk is moderately low , but if you have a in high spirits rigour nonstarter , even if you have a low probability , that can change the calculation , ” he said .
Wolfson pronounce that CPSC oftentimes does recall even when no incident or injuries have been reported .
“ The legal philosophy allows for companionship to carry out callback before the first reports of consumer job come in . “ It could be six with 4.1 million units or none with 1,000 . You still have the ability to do the recollection , ” Wolfson say .
Any company that knows that their product poses a substantial hazard is under federal responsibility to report it to CPSC immediately , Wolfson said . However , he worsen to say whether metal corpuscle contamination of Li - ion amaze such a hazard .
Catastrophic failures of the Li - ion assault and battery , though rare , can be “ very dramatic , ” Doughty aver . “ You get a pile of fireworks . ”
