Hydrogen vs. Battery Electric Cars

Diana, what is the life span of the hydrogen fuel cells?  I was involved in a project about 15 years ago where back up electricity was provided with hydrogen.  With that technology the fuel cells need maintains every 1500 hours.  I'm sure it's a lot better now, but how much?  Will the fuel cells last as long a the car, or will they need to be replaced periodically?  And what will the cost be?