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Old 7th February 2013 | 09:24
  #665 (permalink)  
cockney steve
 
Joined: Jan 2008
Posts: 1,191
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From: lancs.UK
Yesterday, I read a big section i'd missed on the Tech.forum thread/

THE CELLS ARE EACH COMPOSED OF SEVERAL (7?) SMALL CELLS IN PARALLELL

In essence, this works like your car-battery, several plates alternately stacked pos-neg-pos-neg to get the surface-area for the capacity and discharge-rate required.....all the plates of each polarity are linked together, so there's only 1 Pos and one Neg connection.

The problem with these Lithium Cells, is the charger ONLY MONITORS THE CELL_GROUP AS A WHOLE.
I don't pretend to know how sensitive the monitoring-system is, but now believe that the internal configuration and control-boards of the Thales "power storage box" needs a serious looking at......OOPS They're going to do that.

The charging-unit MUST be able to see yhe individual sub-cells in a stack which form one of the 8 cells in the battery.....once a small sub-cell runs -away, it would appear a domino-effect teces place and the thermal-runaway cascades through the entire battery.

Poor battery design, for the application and poor charger design which fails to adequately monitor and counter the inadequacies in the battery-pack it's supposed to control.......
all just my opinion ,of course.
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