Electrostatic oil mist separator for internal combustion engine

An electrostatic oil mist separator for an internal combustion engine, comprising:

• a positive plate and a negative plate facing each other;
• a filter comprising an electrically insulating material and arranged between the positive plate and the negative plate;
• a case having an inlet and an outlet and houses the positive plate, the negative plate, and the filter;
• and
• a voltage generator configured to apply a voltage across the positive plate and the negative plate, wherein
• the electrostatic oil mist separator is configured to cause blow-by gas to flow from the inlet to the outlet between the positive plate and the negative plate in a state in which the voltage generator is applying a voltage across the positive plate and the negative plate, thereby separating oil mist from the blow-by gas by electrostatic adsorption force, and
• at least one of the positive plate and the negative plate is made of a metal plate and includes a plurality of protrusions that are formed by cutting and raising the metal plate.