I am trying to get a handle on ripple current ratings for capacitors, start ing with the ChemiCon KZN series. The data sheet has specifications for ra ted ripple current and maximum temperature. It seems I can reliably operat e well beyond the ripple current rating, but I don't have a good understand ing of what the real limitations are.
How do capacitor manufacturers come up with the ripple current rating for t heir parts? I had thought this was mostly a function of the capacitor's in ternal temperature, and the effect on the electrolyte. If it gets too hot the electrolyte might boil, or in a less extreme case the electrolyte perme ates through the plug faster effectively reducing the life of the capacitor . Does this sound correct? From the little bit of testing I have been doi ng, it seems more complicated than that. I would like to come up with a go od way to measure this or otherwise put numbers on it.
Does anyone know of a good reference for the design of capacitors? I would like to get a better understanding of the chemistry. From what little I k now, the chemistry in the electrolyte is pretty sophisticated. This is a m ature technology.
Thanks,
Ethan