HOME  |  NEWS  |  BLOGS  |  MESSAGES  |  FEATURES  |  VIDEOS  |  WEBINARS  |  INDUSTRIES  |  FOCUS ON FUNDAMENTALS
  |  REGISTER  |  LOGIN  |  HELP
Page 1/4  >  >>
naperlou
User Rank
Blogger
Going back
naperlou   3/8/2013 10:12:01 AM
NO RATINGS
Chuck, is there any reason they just don't go back to a known battery technology?

Charles Murray
User Rank
Blogger
Re: Going back
Charles Murray   3/8/2013 10:20:26 AM
NO RATINGS
As far as I know, naperlou, the only reason to use lithium-ion is the energy density. Higher energy density means they can cut weight, which is of course always important in aircraft design.

Gorski
User Rank
Platinum
787 batteries need liquid cooling
Gorski   3/8/2013 3:01:44 PM
NO RATINGS
The solution seems to be liquid vs. air cooling. The article states that air is less dense at higher altitudes and is less efficient in cooling anything even though it's at a lower temperature. Volt has gone to liquid cooling that works. What is Boeing waiting for? Call the GM engineers and find out what they did. A Volt did go on fire a little while ago.

Charles Murray
User Rank
Blogger
Re: 787 batteries need liquid cooling
Charles Murray   3/8/2013 4:29:38 PM
NO RATINGS
Yes, Gorksi, it's a matter of liquid versus air cooling. It's also a matter of passive versus active cooling. As far as we can tell, Boeing is using passive air cooling. There reportedly are no fans to draw the hot air away. Toyota uses air cooling on its Prius PHV, but it is active air cooling -- they use three fans to draw the heat away from the battery's cells.

Cabe Atwell
User Rank
Blogger
Re: 787 batteries need liquid cooling
Cabe Atwell   3/8/2013 4:56:36 PM
NO RATINGS
My friend's PC in water cooled, every component. If that slacker can do it, I don't see why Boeing can't do the same.

C

Charles Murray
User Rank
Blogger
Re: 787 batteries need liquid cooling
Charles Murray   3/8/2013 6:34:38 PM
NO RATINGS
I don't know how much it would cost to add liquid cooling, Cabe. In today's electric cars and plug-in hybrids, packaging is said to be about 50% of the cost of the entire battery package. How much that differs between passive and active cooling situations, I don't know. Whatever the cost, though, the production volumes for a 787 are ridiculously small compared to those of a production car, so the cost wouldn't be multiplied by hundreds of thousands of units.

g_ost
User Rank
Gold
Re: 787 batteries need liquid cooling
g_ost   3/9/2013 3:18:56 AM
NO RATINGS
Liquid cooling is not my favorite solution. The thermal energy developed during lithium ion battery charge discharge cycles should be just moved away from the source. To obtain an efficient thermal energy transport the use of heat pipes will bring much more benefit. In case of battery thermal runaway the water system will be a big, big problem.

a.saji
User Rank
Silver
Re: 787 batteries need liquid cooling
a.saji   3/10/2013 9:07:16 AM
NO RATINGS
@g_ost: Good point mate. Do you think liquid cooling has an dangerous affects?   

g_ost
User Rank
Gold
Re: 787 batteries need liquid cooling
g_ost   3/10/2013 11:25:38 AM
NO RATINGS
Thermal runaway occurs at 120 -200 deg. Celsius, is a strong exoterm reaction which can not stop until all active material is consumed. Actually is the liquid electrolyte which starts decompose. The only commercial available technology able to transfer more than100 watt/ cm2 is the heat pipe. Boeing should have experience with this technology. It was extensive in the spacecraft technology to cool the sunside of a spaceship (transfer the heat from the hot to the cool side). More than that the heat can be transferred to a heat exchanger outside the battery walls (trough the firewalls). Another system should be also included to cool down the cells at bellow 20 degrees Celsius where the liquid electrolyte ions stop to move (available for the military technology). This approach is possible to be implemented with special designed hot pipes at reduced volumes. The space for the cooling pipes (integrated into cooling plates between the cells) is the same as with the current (empty space between the cells) Boeing solution. Yes, Walter can be dangerous, if water comes in contact with battery electrodes the battery will explode.

Elizabeth M
User Rank
Blogger
Re: 787 batteries need liquid cooling
Elizabeth M   3/11/2013 8:00:54 AM
NO RATINGS
You've been all over this story, Chuck, and it seems like it will continue for awhile. Great coverage. I agree that it seems to be a liquid vs. air debate. Perhaps some of the latest research I've covered about lithium-ion battery design could be helpful in terms of what best way to design the battery so this doesn't happen again. I guess it's a little too late to start from scratch, though, so Boeing will have to fix the problem based on what it's already done.

Page 1/4  >  >>


Partner Zone
Latest Analysis
Some cars are more reliable than others, but even the vehicles at the bottom of this year’s Consumer Reports reliability survey are vastly better than those of 20 years ago in the key areas of powertrain and hardware, experts said this week.
While risk management sounds like one activity, in order to be conducted effectively, it must be broken down into three sub-components: risk assessment, risk monitoring, and response planning.
Many of the materials in this slideshow are resins or elastomers, plus reinforced materials, styrenics, and PLA masterbatches. Applications range from automotive and aerospace to industrial, consumer electronics and wearables, consumer goods, medical and healthcare, as well as sporting goods, and materials for protecting food and beverages.
In a speech at China's National People’s Congress in Beijing this month, Premier Li Keqiang laid out plans to revamp the country's manufacturing infrastructure with advanced technology.
While many larger companies are still reluctant to rely on wireless networks to transmit important information in industrial settings, there is an increasing acceptance rate of the newer, more robust wireless options that are now available.
More:Blogs|News
Design News Webinar Series
2/25/2015 11:00 a.m. California / 2:00 p.m. New York
12/11/2014 8:00 a.m. California / 11:00 a.m. New York
12/10/2014 8:00 a.m. California / 11:00 a.m. New York
3/31/2015 11:00 a.m. California / 2:00 p.m. New York
Quick Poll
The Continuing Education Center offers engineers an entirely new way to get the education they need to formulate next-generation solutions.
Mar 30 - Apr3, Getting Hands-On with Cypress’ PSoC
SEMESTERS: 1  |  2  |  3  |  4  |  5  |  67


Focus on Fundamentals consists of 45-minute on-line classes that cover a host of technologies. You learn without leaving the comfort of your desk. All classes are taught by subject-matter experts and all are archived. So if you can't attend live, attend at your convenience.
Learn More   |   Login   |   Archived Classes
Twitter Feed
Design News Twitter Feed
Like Us on Facebook

Sponsored Content

Technology Marketplace

Copyright © 2015 UBM Canon, A UBM company, All rights reserved. Privacy Policy | Terms of Service