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Samsung Gets Kicked Off the Plane

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NielV0
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Lithium-metal chemistries
NielV0   9/15/2016 3:58:17 PM
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LiFePO4 is the best known lithium-metal chemistry, but it is actually a family of safe chemistries involving lithium and metals.  Energy density is lower due to a terminal voltage of only 3.2V, cost is a bit higher, but it is still manageable and its safety and environmental advantages can be turned into a selling point.

#1 "Norma;" Li-Ion has a weak bond with oxygen, where as LiFePO4 has the ocygen and phosfor strongly bonded.  By the time LiFePO4 releases oxygen (around 550 degC), you have numerous other issues...

#2 "Normal" Li-Ion has a thermal runaway rate of around 440 degC per minute, where as LiFePO4 is only 5 degC per minute.

#3 LiFePO4 actually works better at elevated temperature around 60 degC, making them ideal for outdoor use in direct sunlight when you need the power to drive displays.

#4 The chemicals in LiFePO4 is much wider available than for "normal" lithium batteries, with huge depositsa in Australia and China.

Don Herres
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Not just cell balancing
Don Herres   9/14/2016 2:47:53 PM
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You are, of course, correct that the batteries will fail without proper cell balancing.

However, manufacturing defects in the cell membrane can cause spectacular failures as shown by the SONY flaming laptops a few years ago.  In this case, Samsung only has problems with one of two suppliers which points to a weaker design or manufacturing defects.

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