Covering the inside of a mini Peltier fridge with aluminum foil would generally have a negative impact on its cooling ability.
A Peltier fridge, also known as a thermoelectric cooler, operates based on the Peltier effect, which utilizes the temperature difference between two surfaces of a semiconductor to transfer heat. The device consists of a Peltier module that contains two plates, one referred to as the hot side and the other as the cold side. The hot side absorbs heat, while the cold side dissipates heat.
When you cover the inside of the Peltier fridge with aluminum foil, you effectively insulate the cold side of the Peltier module. Aluminum foil is a good conductor of heat and acts as a barrier that restricts heat transfer between the cold side and the interior space of the fridge. As a result, the cooling capacity of the Peltier module is reduced.
Without proper heat dissipation from the cold side, the temperature gradient required for effective cooling is compromised. The Peltier module becomes less efficient at transferring heat from the interior of the fridge to the cold side, thereby reducing its ability to cool.
It's worth noting that the Peltier module itself already has a heat sink or heat dissipation mechanism on the cold side, typically in the form of a metal plate or finned structure. This design is intended to maximize heat dissipation and optimize cooling efficiency. Adding aluminum foil interferes with this design and disrupts the heat transfer process.
In conclusion, covering the inside of a mini Peltier fridge with aluminum foil hinders heat dissipation and compromises its cooling ability. It is generally advisable to avoid obstructing the cold side of a Peltier module to ensure optimal cooling performance.