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The practical application of lithium (Li) metal battery is impeded by the Li dendrite growth and unstable solid electrolyte interphase (SEI) layer. Herein, an ultra‐stretchable and ionic conducting chemically crosslinked pressure‐sensitive adhesive (cPSA) synthesized via the copolymerization of 2‐ethylhexyl acrylate and acrylic acid with poly(ethyleneglycol)dimethacrylate as crosslinker (short for 70cPSA), is developed as both artificial SEI layer and solid polymer electrolyte (SPE) for stable Li‐metal electrode, enabling all‐solid‐state Li metal batteries with excellent cycling performance. As an artificial SEI layer, the 70cPSA‐modified electrodes exhibit excellent electrochemical performance in Li|70cPSA@Cu half cells and 70cPSA@Li|70cPSA@Li symmetric cells. In full cells with LiFePO4 (LFP) as cathode, the 70cPSA@Li|LFP cell exhibits stable cycling performance over 250 cycles. Utilized as SPE, the all‐solid‐state Li|SPE|LFP cell delivers excellent cycling stability with a capacity retention of 86% over 500 cycles. With high‐voltage LiNi0.8Mn0.1Co0.1O2 (NMC811) as cathode, the Li|SPE|NMC811 cell exhibits a discharge capacity of 124.3 mAh g−1 with a capacity retention of 71% after 200 cycles. The rational design of PSAs and investigation of their dual role for stable and safe Li‐metal batteries may shed a light on adhesive polymers for battery applications.

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Large-amplitude Fourier transform alternating current (FTAC) voltammetry has been used to parameterize the electrode kinetics associated with the reduction of α-[S2W18O62]4– in acetonitrile containing [n-Bu4N]­[PF6] as the supporting electrolyte at glassy carbon (GC), gold (Au), and platinum (Pt) electrodes by experimenter-based heuristic and computer-assisted automated approaches. The electron-transfer kinetics described by the Butler–Volmer relationship are faster at GC than at the metal electrodes. Progressively increasing departures from ideality in the experimental versus simulated data comparisons were found with reduction processes that occur at more negative potentials and with higher electrolyte concentrations. Ion pairing between α-[S2W18O62]4– or its reduced forms and the electrolyte cation may contribute to nonconformance between theory and experiment. Electrochemical quartz crystal microbalance experiments along with other experiments reveal that adsorption of more extensively reduced species may modify the electrode surface and contribute to the asymmetry found in the reduction and oxidation components of the FTAC voltammetric data. Enhanced double-layer effect at negative potentials could also explain why the level of nonideality increases with reduction processes that occur at more negative potentials. The findings in this study are expected to apply to the voltammetric reduction of other negatively charged polyoxometalates.

The present study describes the associated relationship between the length-weight, sex ratio and related condition factor of Tenualosa ilisha based on the length and weight data collected from the commercial landing station of BFDC, Cox’s Bazar, from January 2019 to December 2019. The work was carried out on 866 specimens (307 male and 559 female) ranging from 8.4 to 53.6 cm in length and weight of fishes ranging from 7 to 1977g, respectively. The reproductive attributes of T. ilisha appeared in the sex proportions (M: F=1:2) which revealed the prevalence of females in comparison with males. The external observation was taken into consideration to determine the gender of Hilsa. The relationship of length-weight was fitted with the pooled data for males and females independently of all month-to-month samples which results the BW=0.0104TL2.9795 (R2=0.9636) and BW=0.0019TL3.4689 (R2=0.8461) respectively. The results expressed a higher correlation in between the length-weight (r>0.91). The length wise relative condition factor of T. ilisha was estimated as 1.02, 0.9, 1.05, 1.03, and 1.02 at the length group of 0-20, 21-30, 31-40, 41-50, 51-60 respectively indicating fluctuation of condition factor within the size group. The overall KR for T. ilisha was 0.9-1.22 in which maximum KR was found in July while the minimum was in March. The KR was strongly correlated with TL and BW.