Application note from International Rectifier on various method for thermal management. Link here (PDF)
In many electronic applications, temperature becomes an important factor when designing a system. Switching and conduction losses can heat up the silicon of the device above its maximum Junction Temperature (Tjmax) and cause performance failure, breakdown and worst case, fire. Therefore the temperature of the device must be calculated not to exceed the Tjmax. To design a good Thermal Management solution, the Tj should always be kept at the lowest operating temperature.
If you plan a payload for a rocket / high altitude balloon, heat can become an issue.
Convection drops with altitude, while lower ambient temperatures can impact batteries.
Conducting heat, from components to a battery pack, is not a solution you’d usually consider at sea level.