WP3 addresses electrode/electrolyte interfaces (SEI) aiming to: 
    - Develop innovative ways of in situ SEI characterization. 
- Investigate SEI interfaces using ex situ and “post mortem” methods. 
- Understand SEI forming additives (SEI builders). 
- Develop new and more efficient SEI additives. 
- Realize polymer ion conducting membranes mimetic of the SEI and investigate their mechanical and electrochemical properties.