I didn't mean to offend with the linkfluxno wrote: ...... they state that its "internaly pressure compensated" i'm not sure what they mean with that .....
These are Lithium Ion cells, a completely different chemistry to Lithium Polymer cells.fluxno wrote: This report is done by some norwegian scientists(i found it by googling) and they pressure test lithium (ion i think) batteries because of a failure on a battery pack on an PIG that exploded because pressure came inside the vessel, and compressed the cells so they exploded, and then damaging the container. http://www.ffi.no/no/Publikasjoner/Docu ... essure.pdf
Your rather simple analogy of a ping pong ball imploding is valid for ping pong balls but not really Lithium Polymer batteries, oil at pressure will tend to find its way into most cracks and crevices of an assembly of components and equalise the pressure across the mechanical interfaces by squeezing out any air in there.
Lithium polmer cells are fundamentally solid components with no air voids in them.
http://www.youtube.com/watch?v=FbVUpkoHxoU
See, no ping pong balls
When a company connects a number of cells together to form batteries it shouldn't be introducing any voids into them, just wiring them together.
I guess we'll just have to agree to disagree
Martin