Through improvements to the MEA (membrane electrode assembly) and the separator flow path, Nissan engineers have significantly improved the power density of its newest generation fuel cell stack by 2.5 times greater than its 2005 model. The result, according to the company, is considered a world's best (among automakers) of 2.5 kW/L. The 2011 model fuel cell stack features integration of the MEA with the MEA supporting frame via molding. This provides for single-row lamination of the fuel cell, reducing its overall size by more than half compared to conventional models. Also realized in the development process was a one-quarter reduction in both parts variation and platinum usage. These improvements helped reduce overall cost of the fuel cell stack to one-sixth that of the 2005 model.