유동주 교수

In lithium metal batteries, electrolytes containing a high concentration of salts have demonstrated promising cyclability, but their practicality with respect to the cost of materials is yet to be proved. Here we report a fluorinated aromatic compound, namely 1,2-difluorobenzene, for use as a diluent solvent in the electrolyte to realize the "high-concentration effect". The low energy level of the lowest unoccupied molecular orbital (LUMO), weak binding affinity for lithium ions, and high fluori

Abstract Lithium metal anodes are steadily gaining more attention, as their superior specific capacities and low redox voltage can significantly increase the energy density of rechargeable batteries far beyond those of current Li‐ion batteries. Nonetheless, the relevant technology is still in a premature research stage mainly due to the uncontrolled growth of Li dendrites that ceaselessly cause unwanted side reactions with electrolyte. In order to circumvent this shortcoming, herein, an ionic li

Abstract Nonaqueous carbonate electrolytes are commonly used in commercial lithium‐ion battery (LIB). However, the sluggish Li + diffusivity and high interfacial charge transfer resistance at low temperature (LT) limit their wide adoption among geographical areas with high latitudes and altitudes. Herein, a rational design of new electrolytes is demonstrated, which can significantly improve the low temperature performance below −20 °C. This electrolyte is achieved by tailoring the chemical struc

Abstract Contrary to early motivation, the majority of aluminium ion batteries developed to date do not utilise multivalent ion storage; rather, these batteries rely on monovalent complex ions for their main redox reaction. This limitation is somewhat frustrating because the innate advantages of metallic aluminium such as its low cost and high air stability cannot be fully taken advantage of. Here, we report a tetradiketone macrocycle as an aluminium ion battery cathode material that reversibly

Abstract Despite their unparalleled theoretical capacity, lithium‐metal anodes suffer from well‐known indiscriminate dendrite growth and parasitic surface reactions. Conductive scaffolds with lithium uptake capacity are recently highlighted as promising lithium hosts, and carbon nanotubes (CNTs) are an ideal candidate for this purpose because of their capability of percolating a conductive network. However, CNT networks are prone to rupture easily due to a large tensile stress generated during l

Low-temperature electrolytes (LTEs) have been considered as one of the most challenging aspects for the wide adoption of lithium-ion batteries (LIBs) since the SOA electrolytes cannot sufficiently support the redox reactions at LT resulting in dramatic performance degradation. Although many attempts have been taken by employing various noncarbonate solvent electrolytes, there was a lack of fundamental understanding of the limiting factors for low-temperature operations (e.g., -20 to -40 °C). In

The state-of-the-art all-solid-state batteries have emerged as an alternative to the traditional flammable lithium-ion batteries, offering higher energy density and safety. Nevertheless, insufficient intimate contact at electrode-electrolyte surface limits their stability and electrochemical performance, hindering the commercialization of all-solid-state batteries. Herein, we conduct a systematic investigation into the effects of shear force in the dry electrode process by comparing binder-free

A variety of electrolyte engineering strategies have been introduced to extend the cycle life of lithium metal batteries (LMBs). These strategies can be largely grouped into two categories: those that induce a solvent-driven vs those that induce an anion-driven solid electrolyte interphase (SEI) layer. Although each strategy has proven to be effective for SEI manipulation, they are not yet comprehensively understood. Here, lithium salts with different dissociation abilities are systematically sc

The inherent limitations of lithium (Li)-ion batteries have sparked interest in exploring alternative technologies, especially those relying on metallic anodes: monovalent Li and divalent zinc (Zn), magnesium (Mg), and calcium (Ca) metals. In particular, Mg and Ca metal batteries offer significant advantages based on the natural abundance of their raw materials and high energy-storage capabilities resulting from the bivalency of the carrier ions. Yet, these battery systems are far from commercia

Abstract Lithium metal has been hailed as a key enabler of upcoming rechargeable batteries with high energy densities. Nonetheless, uncontrolled dendritic growth and resulting formation of a nonuniform solid‐electrolyte‐interphase (SEI) layer constitute an ever‐challenging obstacle in long‐term cyclability and safety. So far, these drawbacks have been addressed mainly by using noncarbonate electrolytes based on their relatively mild decomposition under reductive environments. Here, toluene as a

Aluminum batteries are of great interest in "beyond-lithium" battery research because of their remarkably high performance in terms of rate capability and cycle life, in addition to the intrinsic advantages of aluminum metal such as its natural abundance and high theoretical capacity of 8056 mAh cm^-3. The electrochemical performance that has been achieved thus far is unusual, as cells usually adopted viscous ionic liquid (IL) electrolytes with bulky complex carrier ions. Herein, we no

A sodium polyacrylate (NaPAA) binder induces the formation of a stable and Na-ion conductive NaPO2F2-rich cathode–electrolyte interphase layer via a displacement reaction.

Abstract Based on the recent discovery of the ionic liquid involving the AlCl 4 − ‐Al 2 Cl 7 − redox couple as an electrolyte, aluminum (Al) rechargeable batteries have received revamped interest. However, the corrosive nature of the chloride ion and Al 2 Cl 7 − makes it challenging to find suitable current collectors and cathode materials. Here, we screen various metals and carbon materials as current collectors, and indeed find that none of the metals commonly used for battery current collecto

Abstract In lithium metal batteries, electrolytes containing a high concentration of salts have demonstrated promising cyclability, but their practicality with respect to the cost of materials is yet to be proved. Here we report a fluorinated aromatic compound, namely 1,2‐difluorobenzene, for use as a diluent solvent in the electrolyte to realize the “high‐concentration effect”. The low energy level of the lowest unoccupied molecular orbital (LUMO), weak binding affinity for lithium ions, and hi