I am relatively new to composting and still have not figured out how to generate heat so for now it is mainly cold composting. I was wondering if it is a good idea to put egg shells in the compost bin both to make sure it decomposes fast but also to ensure it does not attach mice or voles.
Yes,they can be added to your compost bin or pile - quicker to break down if you smash them up, but they don't have to be. Some people rinse out the inside first so as not to encourage rodents, but if you have an actual closed bin, that shouldn't really be necessary. More info here: Eggshells In The Garden: Using Eggshells In Soil, Compost And As Pest Control.
There's considerable doubt that egg shells decompose in any significant fashion especially if the soil is not acidic.
If you want to benefit the soil at all, best would be to grind into a fine powder before adding to your soil or compost, and maybe the worms will use it.