For a better understanding of the temperature specs of electrolytic caps 
I recommend looking at some high power high voltage cap datasheets. 
There you usually find graphs with useful live versus ripple current and 
temperature and more. Evene if your cap datasheet does not have this 
info, it gives you a general clue how the different parameters work 
together. And be careful how the manufactor specifies the temperature 
value! Is it body temp, surface or ambient? How is ambient defined and 
so on...

One quick example:
Look at the B43511 series from epcos

Regards,
Florian

Sean Breheny wrote:
> Hi all,
> 
> Can anyone tell me exactly what the temperature rating for aluminum
> electrolytic caps means? When the datasheet says 105 deg C max, which
> of the following (if any) does this mean:
> 
> a) the capacitor will operate within specs (including max ripple
> current) when the ambient temp is 105 deg C (so the case could
> actually be 20 to 30 deg C hotter)
> 
> b) the capacitor will operate within specs when the case is 105 deg C
> (so the ambient may need to be 20 to 30 deg C cooler if running at max
> ripple current)
> 
> c) the capacitor will operate within specs when the maximum internal
> temperature (hot spot) is 105 deg C (very difficult to determine
> without more data from the manufacturer)
> 
> Thanks,
> 
> Sean

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