Weird cell degradation

[BrianG]

That doesn't look like your typical puffing from internal gas expansion where it would expand the whole pack and be squishy in a more uniform manner. I wonder if that's from the sudden stops during crashes or front-heavy landings causing the "stuff" inside the cell to bunch up against the front?

[pinkpanda3310]

I think not. Each cell is swolen at the positive end ie- top cell big on left side next cell big on right side.

if you puncture a lipo it will let air in....then it will start to react and oxidize.
if its punctured its as good as dead...and really smelly too
chris

[pinkpanda3310]

So you think they were poorly manufactured? That's why 4 of the cells have puffed in the same way. The pack is as good as dead but I was just curious about the deformation.

i did read up about lipos a few years ago, as a child i was into electronics....im more into mechanics and engineering rather than chemistry, so i didnt understand all of the text.

basically in certain situations like over discharge and over draw, oxygens are created inside the pack....puffing, the oxygene will start to oxydize the internal tabs on the lipo which pickup the voltage and take it out the pack.

this accelerates the degredation of the pack...once it starts there is no stopping it, basically rots the tabs...which creates more heat...

no i dont think they where poorly made...just well used
chris

[pinkpanda3310]

I can soughta understand that

Thanks for the insight Chris

one more fact i just thought of while i was just repairing a bouncy castle blower...DC voltage allways flows in one direction...this would explain why the packs are swollen at one end only..now i cant remember if its + to - or - to +.
durr.... the old grey matter is not as good as it used to be
chris