Unless you invest in a little jetpack that will allow you to hover over the ice, slipping is always going to be a possibility (or if you invest in a pair of metal snow cleats that slip over your footwear). However, a good outsole is going to be an excellent way to mitigate that potential risk. Keep an eye out for terms like anti-skid or anti-slip, because these types of materials have a bit of a tacky texture to the sole that will grab onto any friction found in the ice to reduce your risk of slipping.