App note from KEMET on long life electrolytic capacitors. Link here (PDF)
The service life for high quality power supplies and automotive power electronics is often limited by electrolytic capacitors’ operational life (Lop). Very long life (> 20 years at temperature up to 75C) is possible to be achieved by choosing capacitors with optimized design. Type of electrolyte, capacitors lid design, sealing method and rubber material quality, are important factors which determine the Lop.