| 초록 |
As the demands for higher power-density and higher energy-density lithium-ion batteries continue to grow, the accompanying safety concerns are issued as a critical challenge. From the viewpoint of battery safety failures, a separator is considered a key component to secure the battery safety, because its primary function is to keep physical isolation between a cathode and an anode of a battery in order to prevent their electrical contact. In general, separators in lithium-ion batteries are made mostly of polyolefins, usually polyethylene (PE) or polypropylene (PP). Though these polyolefin-based separators are widespread and have many advantages, their poor thermal stability and mechanical strength have raised serious concerns in maintaining the electrical isolation between electrodes, particularly under vigorous conditions such as abnormal heatings or mechanical ruptures. In addition, the poor wettability of the polyolefin-based separators due to their intrinsic hydrophobicity becomes a critical challenge as the importance of large-sized batteries targeting electric vehicles is rapidly growing. In this presentation, in a bid to breakthrough the fore-mentioned limitations of the polyolefin-based separators, we introduce new insights into how to design separators, which covers the nanostructured ceramic layer-coated separators and highly close-packed polymer nanoparticle array-coated separators. Major characteristics of the separators, specifically, microporous structure, liquid electrolyte wettability, thermal stability, and electrochemical performance are extensively investigated in terms of the separator design parameters. |
