Panasonic, one of supplier of all aluminum and tantalum polymer capacitor technologies provide comparison of its technologies as follows:
The following chart is demonstrating lifetime with temperature comparison of wet vs polymer vs hybrid aluminum capacitors that can be helpful for a specific application selection guide.
DCL and balancing
Aluminum electrolytic capacitors leakage current and balancing is explained in more details in a paper below:
DCL of Aluminum Electrolytic Capacitors – by Dr. Arne Albertsen from Jianghai Europe Electronic Components GmbH
*10 min read
Construction of aluminum capacitors and wet to polymer capacitor comparison also featured in EETimes ChalkTalks by Kemet:
What are Aluminum Polymer Capacitors? — KEMET and Mouser Electronics EE Journal Chalk Talks