I'm betting that the BMS (or abuse) ran a cell (or two) low. The
dendrites formed when the cell was low. Then the battery attempted to
charge and the undercharged cell(s) overheated.
Essentially, they ran the battery (or cells in the battery) below the
allowed voltage, then charged it. A light left on? Just my opinion.
If they had simply used LiFePO4 they would not have any of these problems.
http://news.investors.com/print/business/011813-641159-boeing-may-switch-lithium-battery-design-in-787-dreamliner.aspx
The specific Cobalt Oxide cell they used were not any energy
advantage over LiFePO4 in that they were only 90 W-hr/kg. (LiFePO4
are 110 W-hr/kg.) They were apparently chosen based on political reasons:
http://www.nytimes.com/2013/01/26/business/selection-of-the-boeing-787s-battery-maker-raises-questions.html?partner=yahoofinance&_r=1&;
Bill D.
At 12:12 PM 2/13/2013, you wrote:
I read that they detected dendrites in still-good batteries and consider
them a possibility of shorting in the cells that burned. However, I thought
this was still inconclusive.
Peri
-----Original Message-----
From: [email protected] [mailto:[email protected]] On Behalf
Of Cor van de Water
Sent: 13 February, 2013 10:56 AM
To: [email protected]
Subject: [EVDL] Boeing 787 battery fire caused by shorted cell
It is only still not clear whether the cell shorted internally
(manufacturing defect) or from external causes.
http://www.ntsb.gov/news/2013/130207.html
Cor van de Water
Chief Scientist
Proxim Wireless Corporation http://www.proxim.com
Email: [email protected] Private: http://www.cvandewater.com
Skype: cor_van_de_water XoIP: +31877841130
Tel: +1 408 383 7626 Tel: +91 (040)23117400 x203
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