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Free minder
Join Date: Nov 2001
Location: Middlessex county, MA
Posts: 9,415
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In Li-ion cells, overcharge is dangerous because it may create lithium dendrites that poke through the separator and create a short through which the cell discharges instantly. The very high current flowing through the dendrite causes a very hot spot which ignites the electroyte, and poof, there goes your cellphone in smoke.
The BMS is designed to prevent overcharge, but it cannot really detect if an overcharge condition is occuring locally on the electrode.
Apparently the issue with Samsung cells was pressure differences on the cell stack causing local overcharge conditions.
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1978 SC Targa, DC15 cams, 9.3:1 cr, backdated heat, sport exhaust https://1978sctarga.car.blog/
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