Combining the advantages of both liquid and solid electrolytes with magneto-rheology

摘要

Electrolytes are one of the most important components in any electrochemical cell (1), including batteries. Usually, liquid electrolytes have high ionic conductivity (2) but poor mechanical strength and are potentially not safe because of possible leakage and flammability (3). Solid electrolytes can reduce the possibility of fire accidents and provide sound mechanical strength in case of impact (4) but typically have relatively poor ionic conductivities (5). To combine the advantages of both liquid and solid electrolytes, here we demonstrate a novel solid electrolyte based on magneto-rheological fluids (MRFs). Magneto-rheology refers to the reversible and rapid change of MRFs from liquid to semi-solid or solid when an external magnetic field is applied (6). The phase change stems from the dipolar interaction that is introduced by the external magnetic force, which initiates the formation of chain-like alignment. MRFs are an important class of smart materials that are used in a variety of applications, such as vibration control, torque transmission14"16, robotics and micro-electronic devices.