PPRuNe Forums - View Single Post - Another 787 electrical/smoke incident (on ground)
Old 14th Jan 2013, 20:39
  #183 (permalink)  
henra
 
Join Date: May 2010
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Originally Posted by grebllaw123d
Tu.114,

Unfortunately, moving the battery to an unpressurized position is not possible - I had the same thoughts until I read the spec. for the cells: min. operating temp. is minus 18 degrees C.
The minus 18°C is the ultimate lower limit. However Lithium Cells (off all kinds that I'm aware off) increase their internal resistance drastically at low temperatures. Drawing high currents at low temperatures can damage them.
Typically they are starting to feel well (meaning low internal resistance, high C rate capability) at room temperature.
They deliver best performance at around 50 - 60°C. Unfortunately that is close to the point where self -destruction starts (Usually between 75 and 95°C). They are not well suited to cold operation at all. That is a big disadvantage in power tools as well.
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