Wow. Thanks for this, Chuck. Definitely a developing story. I'm delighted to hear that there is collaboration (or at least a coalition) of lithium-ion battery users that are willing to swap experience with these systems. I'm sure this type of information sharing between CEOs has happened since the dawn of time, but I'm encouraged that it can be facilitated by social networking such as twitter and not left to chance meetings on the putting green at the club. I'm sure networking at the Engineer level is still best found at the Dearborn Heights Applebee's, but online story swapping is another emerging development that helps to accelerate the exponential technology development curve...
Chuck, Outstanding coverage. It's amazing how all of this is playing out in the online media. But it's also obvious there is engineering and science behind the comments. Keep up the good work.
Great that you're keeping on top of this story, Charles. I guess now what we're waiting for is Boeing to admit what it has done wrong and then come up with a plan to fix the problem. I was sort of defending them at first but it actually seems like a fairly major oversight to not proivide a proper cooling system...but maybe they thought they did and it was just an honest mistake. I will continue reading your coverage to see how this unfolds! Let's hope it's a good ending for everyone and Boeing sorts this out.
As an alternative to overcharging and heat dissipation how about over discharging? Over discharge damage is the reason many RC enthuiasists charge their lithium ion batteries outside.
Boeing has recieved 100 batteries back from the airlines as defective. It appears the majority have been inadvertently discharged until the battery low voltage cutoff tripped, disabling the battery. In ANA's case 5 of 10 returns were disabled by the low voltage cutoff. Once a lithuim ion battery has gone below the low voltage limit it is very hazardous to charge. It seems risky procedure for the user to bang up against only battery safety stop during routine ground maintenance. Maybe some batteries have very nearly tripped but were unknowingly flown.
Anticipating the question of why don't the battery electronics cut off discharge at a higher voltage, I don't know. It might have something to do with the fact the batteries are also a last ditch power source to keep flying. I can imagine a situation where you would want every joule you could get out of the battery and willingly scrap it later.
I would discount poor high altitude cooling. The batteries are in the pressurized part of the plane, an equivalent to an altitude of 6000 feet so you still have good heat transfer.
Regarding the issue of whether a battery management IC, by itself, was sufficient protection for the Boeing batteries: We asked Donald Sadoway of MIT that question by e-mail, and his response came in after the story deadline. So here's his response, which arrived late yesterday: "We have evidence that whatever the electrical demands are in the 787, the IC alone doesn't prevent fire. So perhaps the IC isn't right, perhaps the IC is right but the execution is flawed, or perhaps there is some other factor like decompression/compression, which is the result of ascent and descent."
You raise a really good point about the reasons for Musk's collaboration, Nadine. Obviously, no one but Musk knows the full reason, but I imagine there is an element of self-preservation in this. Lithium-ion batteries are getting a going-over in the popular press right now, and some news stories have wondered aloud if lithium-ion is appropriate for electric vehicles. Whether those questions are fair or not, I would imagine that Musk wants people to know that Tesla's battery configuration works safely because the design allegedly makes better allowances for heat dissipation. It's hard to blame him for that.
It is pretty amazing how much media is giving time to the Boeing battery issues. You do not often hear scientific discussion in mainstream media, but the Boeing story has brought out a lot of experts.
Here is a low brainier- GET ALL THE HELP YOU CAN, BOEING!
Tesla has experience with these batteries. Boeing's future rides on a solution to this problem. We all need counselors. Boeing would do well to bring others to the engineering table and utilize their experience.
I hope they already are. Pride has brought down companies and countries. I hope Boeing doesn't let pride get in the way of their future!
By refining topologies and using new fluid technology, Moog's new peak sine drive controller increases available power without increasing controller volume.
Lantronix Inc. has expanded its line of controllers for sensor networks with the release of a rugged controller that improves management of automation systems used in a number of industries, including manufacturing, oil and gas, and chemicals.
Inspired by the hooks a parasitic worm uses to penetrate its host's intestines, the Karp Lab has invented a flexible adhesive patch covered with microneedles that adheres well to wet, soft tissues, but doesn't cause damage when removed.
From Dell / Intel® New Paradigms in Design Work Scott Hamilton, vertical market strategist for Dell Precision workstations, 5/2/2013 3
Early in my career, I worked as a draftsman and remember the days of drawing on vellum with numbered pencils and Mylar with plastic lead. This was a fun experience in the sense that I ...
I've been using workstations for more than 10 years and love finding ways to get more performance from my system. With demanding professional applications that require more power each ...
A lasting memory from my first job as an engineer in an auto assembly plant is standing on hard concrete at six in the morning, vending-machine coffee clutched in hand, listening to ...
A quick look into the merger of two powerhouse 3D printing OEMs and the new leader in rapid prototyping solutions, Stratasys. The industrial revolution is now led by 3D printing and engineers are given the opportunity to fully maximize their design capabilities, reduce their time-to-market and functionally test prototypes cheaper, faster and easier. Bruce Bradshaw, Director of Marketing in North America, will explore the large product offering and variety of materials that will help CAD designers articulate their product design with actual, physical prototypes. This broadcast will dive deep into technical information including application specific stories from real world customers and their experiences with 3D printing. 3D Printing is
To save this item to your list of favorite Design News content so you can find it later in your Profile page, click the "Save It" button next to the item.
If you found this interesting or useful, please use the links to the services below to share it with other readers. You will need a free account with each service to share an item via that service.