| 초록 |
Stress in Li alloy materials inevitably appear during Li insertion and extraction. Here, we demonstrate we can utilize the stress-electrochemistry coupling for novel device concepts. We will show two specific examples in the fields of mechanical energy harvesting and actuation. The energy harvester consists of two identical Li-alloyed Si as electrodes, separated by electrolyte-soaked polymer membranes. Bending induced asymmetric stresses generate chemical potential difference, driving lithium ion flux from the compressed to the tensed electrode to generate electrical current. Removing the bending reverses ion flux and electrical current. Reversing the device concept results in an electrochemical actuator, where Li diffusion coupled to volume expansion drives mechanical actuation and bending. The device concepts exhibit unique advantageous over the existing mechanical energy harvesters or actuators, which include the tunable timescales in energy harvesting and non-volatile actuation capability. We will discuss each in detail in the talk. |
