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Old 13th Feb 2013, 14:44
  #789 (permalink)  
RR_NDB
 
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"AC" cell behaviour

Hi,

HeadingSouth


The issue I seem to thnk about is more the paralleling of cells; as I mentioned before I consider unmatched cells (matching in terms of internal resistance, in 2nd approximation as well internal capacitance and inductance) not very suitable for high-demanding power applications. Whilst at relatively low current settings there are no issues, there certainly are some at high currents or changing loads (AC behaviour of a DC power cell). For as long as cells are just paralleled I agree with previous statements that the paralleling will provide rather stable DC characteristics. But then at AC conditions this looks certainly different.
The big cells (LVP 65) cells were yet fully characterized WRT to transients, superimposed high frequency ripple, etc. ? Boeing selected this battery due his high performance. Highly optimized. Time tells...
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