Class 4 and class 5 storms can damage or destroy a starship. They can also kill the ships crew. When a storm enters a class 4 or class 5 ion storm the ships shields will be rendered inoperative. There are two factors that can prevent a ship from being destroyed. Mass of the ship and the experience level of the crew.
Crews can gain experience from traveling through space and through combat with enemy starships.
Alchemy ships gain experience by using the onboard alchemy machinery. Crew experience is also gained from flying through a storm. Solid matter acts as a damper against the effects of voltage fluxes. If you must travel through a ion storm, be sure to load the ship with as much fuel and cargo as possible. Class 4 and class 5 ion storms will drag starships along with them.