The effect of mechanical surface modification on the performance of lithium (Li) metal foil electrodes is systematically investigated. The applied micro‐needle surface treatment technique for Li metal has various advantages. 1) This economical and efficient technique is able to cover a wide range of surface area with a simple rolling process, which can be easily conducted. 2) This technique achieves improved rate capability and cycling stability, as well as a reduced interfacial resistance. The micro‐needle treatment improves the rate capability by 20% (0.750 mAh at a rate of 7C) and increases the cycling stability by 200% (85% of the initial discharge capacity after 150 cycles) compared to untreated bare Li metal (0.626 mAh at a rate of 7C, 85% of the initial discharge capacity after only 70 cycles). 3) This technique efficiently suppresses Li formation of high surface area Li during the Li deposition process, as preferred sites for controlled Li plating are generated.

is primarily attributed to uncontrolled Li dendrite growth, which inevitably occurs on the Li surface during repeated plating/ stripping processes. Li dendrite-growth leads to battery performance failure and thermal runaway, causing a catastrophic safety failure accompanied by fi re and smoke. With the emergence of Li-ion batteries (LIBs) based on the Li intercalating anode materials represented by carbonaceous anodes in the early 1990s, enthusiasm for developing commercial Li metal secondary batteries has largely diminished. [ 3,[8][9][10] Recently, the need for electric vehicles (EVs) and energy storage systems (ESSs) that require a higher level energy density from electric energy sources than that available from commercialized LIBs has sparked renewed interest in Li metal anodes. Rechargeable batteries using Li metal anodes such as Li/air [11][12][13] or Li/sulfur [14][15][16] batteries are attracting increasing attention as possible alternatives, with many researchers devoting intense efforts to realize these systems. For successful implementation of such nextgeneration battery systems beyond LIBs, signifi cant challenges remain for each battery constituent, including Li metal anodes, cathodes, electrolytes, and battery system design. Above all, harmonious improvement in each fi eld is a prerequisite. Li metal stabilization is a burdensome task because of the well-known diffi culties encountered during the long history of Li battery research and the resultant failure to realize the use of Li metal in a commercialized rechargeable battery system during the last four decades.During the fi rst charging process, the higher cathodic potential compared with the Li ion reduction leads to reductive decomposition of electrolytes, including organic solvents and Li salt on Li metal, and the formation of electrically insulating but ionically conducting protective fi lm called surface electrolyte interphase (or interface, SEI). [ 8,[17][18][19] This passive layer ideally permits Li ion migration and prevents further electrolyte decomposition, enabling stable cycle performance of LIBs in the subsequent cycles. As discussed extensively, [ 18,[20][21][22][23] SEI is understood to be a highly complicated Li ion conducting layer consisting of many different decomposed products with inorganic and organic components, such as Li 2 CO 3 , Li 2 O, LiCO 2 R, LiF, and Li alkoxides. SEI inevitably possesses lateral and vertical non-uniformity, which leads to uneven Li ion conduction. During the charging process, Li ions moving through SEI Repressing uncontrolled lithium (Li) dendrite growth is the top priority for enabling the reliable use of Li metal secondary batteries. On the other hand, the technique controlling the metal plating behavior during metal plating indeed has been considered very diffi cult to achieve. For instance, how can one plate metal ions on the favored selected region during plating? The present study describes how to achieve this goal, i.e., dendrite-free Li deposition, by mechanical surface modifi cation using ...

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Under circumstances of heat stress, heat shock transcription factor 1 (HSF1) plays important roles in heat shock protein expression. In this study, an increasing concentration of dithiothreitol (DTT) was found to either enhance or inhibit the heat-induced trimerization of HSF1, suggesting the involvement of dual redox-dependent HSF1 activation mechanisms. Our in vitro experiments show that the heat-induced bonding between the cysteine C36 and C103 residues of HSF1 forms an intermolecular disulfide covalent bond (SS-I bond) and that it directly causes HSF1 to trimerize and bond to DNA. Gel filtration assays show that HSF1 can form intermolecular hydrophobic interaction-mediated (iHI-m) noncovalent oligomers. However, the lack of a trimerization domain prevents HSF1 activation, which suggests that iHI-m noncovalent trimerization is a precondition of SS-I bond formation. On the other hand, intramolecular SS-II bond (in which the C153, C373, and C378 residues of HSF1 participate) formation inhibits this iHI-m trimerization, thereby preventing SS-I bond formation and DNA binding. Thus, HSF1 activation is regulated positively by intermolecular SS-I bond formation and negatively by intramolecular SS-II bond formation. Importantly, these two SS bonds confer different DTT sensitivities (the SS-II bond is more sensitive). Therefore, a low concentration of DTT cleaves the SS-II bond but not the SS-I bond and thus improves DNA binding of HSF1, whereas a high concentration DTT cuts both SS bonds and inhibits HSF1 activation. We propose that these interesting effects further explain cellular HSF1 trimerization, DNA binding, and transcription when cells are under stress.