BACKGROUND

Electrochemical energy storage is one of the main societal challenges of this century. Though the performances of classical lithium-ion technology based on liquid electrolytes have made great advances in the past two decades, the intrinsic instability of liquid electrolytes results in safety issues.

Solid polymer electrolytes would be a perfect solution to those issues, miniaturization and enhancement of energy density. However, as in liquids, the fraction of charge carried by lithium ions is <20%, limiting the power performances. Solid polymer electrolytes operate at 80°C, resulting in poor mechanical properties and a limited electrochemical stability window.

KEY BENEFITS vs. STATE OF THE ART

We have developed a new type of solid single-ion polymer electrolyte based on polyanionic block copolymers. This electrolyte is particularly well suited for safe and reliable high density energy battery including lithium metal polymer batteries used in electric vehicle, stationary, intermittent energy storage (wind farm…).

• Our material overcomes most of the above limitations

• Very good conductivity at low temperature (1:3x10-5 S cm-1 at 60°C)

• High lithium-ion transport number close to unity (>0.85)

• Excellent mechanical properties: improved mechanical strength compared with electrolyte based on Poly Ethylene Oxide (PEO)

• Enlarged electrochemical stability window spanning 5V versus Li+/Li

• Increased safety through better thermal stability

• Lithium-metal battery prototypes were developed with a substantial gain in power performances compared with state-of-the-art lithium metal battery technology, particularly at 60°C.

Development Status

A prototype battery outperforms a conventional battery based on a polymer electrolyte

APPLICATIONS

• Electric vehicle

• Stationary energy source

• Intermittent energy buffer ponds