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Old 11th Mar 2013, 17:28
  #940 (permalink)  
Lyman
 
Join Date: Aug 2011
Location: Grassy Valley
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I have a fair amount of experience in laminates. If I had to be restricted to one facet of this failure, I would look at the performance (in service) of the roll.

Expansion and contraction, (with and without heat) would happen at variable rates, and substrate performance would be related to the shear of the adhesive relative to the binding strength of the separate layers.

Each cycle would aggravate any weakness from the manufacture, and new and variabe failures would propagate. The system would break down over time, and penetration of electrolyte (conductor) would occur. Hotspots and potential thermal runaway would likely appear, well ahead of optimistic projections.

The evidence is in the photography of the MAIN Battery in the report. The tortuous and serpentine folds show the results of repetitive expansion, contraction, and variable "return Rates" to original.

Conclusion? Each of the layers present in the roll is fragile, in its own way. Each exhibits particular responses to the stresses of environmental and mechanical challenges. The elastic value of the laminated roll is near zero, it wants to remain in the "last" position it had. forcing it to contort in these conditions is degrading the performance of its intended use.

Layerman (Acryl Cellulosic, monolithic Alumina/acrylate, glassfibre/epoxy, two phase cellulosic/phenolic, etc.) Certified in Epon.
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