A. Problem identification
(1S)
As described in the previous section, charging and
discharging an ultra-capacitor is not loss-free process. Because
of the internal resistance, some energy is realized in the ultracapacitor
cell and module as Joule's losses. As a consequence,
the ultra-capacitor internal temperature rises. The temperature
increase depends on the losses and thermal resistance of the
cell and module.
The internal temperature distribution has an enormous
influence on the ultra-capacitor life time. Therefore,
understanding the ultra-capacitor thermal picture and an
optimal cooling strategy are crucially important for an optimal
design of the ultra-capacitor module