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LiNi x Co y Mn 1-x-y O 2 (NCM, x ≥ 0.6) possessing a high nickel content is a favorable cathode candidate for next-generation lithium-ion batteries (LIBs) owing to its ultra-high energy density. However, its sluggish electrochemical kinetics at low temperatures and severe structure destruction at high temperatures limit its practical application. This study presents a facile surface modification strategy based on niobium (Nb) to achieve LiNbO 3 coating and Nb5+ doping, which can address both problems under extreme temperatures (-30-50 °C). More specifically, the LiNbO 3 coating layer can decrease polarization and charge transfer resistance and enhance the structural stability of nickel-rich NCM (LiNi 0·83 Co 0·12 Mn 0·05 O 2); Nb5+ dopants can widen the lithium-ion migration channels and thus improve the diffusion kinetics. The Nb-modified NCM (Nb-NCM) exhibits a high discharge specific capacity at subzero temperatures and excellent stability throughout the temperature range. To further evaluate the practical application potential of the Nb-NCM electrode, full cells are fabricated and tested using the Nb-NCM as a cathode and Li 4 Ti 5 O 12 (LTO) as an anode. Encouragingly, the full cell also shows excellent electrochemical performance between −30 and 50 °C. These findings provide a facile and scalable strategy to enhance the electrochemical performance of nickel-rich NCM across a broad temperature range. • Designing a facile Nb-modification strategy including Nb doping and LiNbO 3 doping. • Nb-NCM shows excellent performance between wide temperature ranges. • Nb-modification improves the structure stability of the high-nickel NCM. • Nb-NCM also shows better electrochemical kinetics. [ABSTRACT FROM AUTHOR]

For the past few years, a new generation of energy storage systems with large theoretical specific capacity has been urgently needed because of the rapid development of society. Lithium–sulfur (Li−S) batteries are regarded as one of the most promising candidates for novel battery systems, since their resurgence at the end of the 20th century Li−S batteries have attracted ever more attention, attributed to their notably high theoretical energy density of 2600 W h kg−1, which is almost five times larger than that of commercial lithium‐ion batteries (LIBs). One of the determining factors in Li−S batteries is how to design/prepare the sulfur cathode. For the sulfur host, the major technical challenge is avoiding the shuttling effect that is caused by soluble polysulfides during the reaction. In past decades, though the sulfur cathode has developed greatly, there are still some enormous challenges to be conquered, such as low utilization of S, rapid decay of capacity, and poor cycle life. This article spotlights the recent progress and foremost findings in improving the performance of Li−S batteries by employing multifunctional metal phosphides as host materials. The current state of development of the sulfur electrode of Li−S batteries is summarized by emphasizing the relationship between the essential properties of metal phosphide‐based hybrid nanomaterials, the chemical reaction with lithium polysulfides and the latter′s influence on electrochemical performance. Finally, trends in the development and practical application of Li−S batteries are also pointed out. [ABSTRACT FROM AUTHOR]

As anode materials for high‐performance Li‐ion batteries, peapod‐like Ge‐based composites, including Ge, a Li‐inactive conducting Cu3Ge, and a porous carbon matrix are synthesized simply by annealing CuGeO3@dopamine in a H2/Ar atmosphere. The introduction of the carbon layer and inactive alloying phase Cu3Ge not only enhances the electrical conductivity of the Ge anode, but also reduces the volume change of Ge during the cell cycle as a buffer. In particular, the anode of this peapod‐like Cu3Ge/Ge@C shows an excellent long cycle life as well as outstanding capacity performance, with a discharge specific capacity up to 934 mA h g−1 after 500 cycles. [ABSTRACT FROM AUTHOR]

Keywords: Li-ion batteries; high-energy density; sulfur; metal phosphides EN Li-ion batteries high-energy density sulfur metal phosphides 1 1 1 09/28/21 20210924 NES 210924 In addition to avoiding the shuttling caused by soluble polysulfides, the design and preparation of sulfur cathodes for Li-S batteries must overcome challenges such as the low use of S, rapid decay of capacity and poor cycle life. This review spotlights recent progress in improving the performance of Li-S batteries by employing multifunctional metal phosphides as host materials. Frontispiece: Multifunctional Metal Phosphides as Superior Host Materials for Advanced Lithium-Sulfur Batteries. [Extracted from the article]

The cathode, a crucial constituent part of Li-ion batteries, determines the output voltage and integral energy density of batteries to a great extent. Among them, Ni-rich LiNixCoyMnzO2 (x + y + z = 1, x ≥ 0.6) layered transition metal oxides possess a higher capacity and lower cost as compared to LiCoO2, which have stimulated widespread interests. However, the wide application of Ni-rich cathodes is seriously hampered by their poor diffusion dynamics and severe voltage drops. To moderate these problems, a nanobrick Ni-rich layered LiNi0.6Co0.2Mn0.2O2 cathode with a preferred orientation (110) facet was designed and successfully synthesized via a modified co-precipitation route. The galvanostatic intermittent titration technique (GITT) and electrochemical impedance spectroscopy (EIS) analysis of LiNi0.6Co0.2Mn0.2O2 reveal its superior kinetic performance endowing outstanding rate performance and long-term cycle stability, especially the voltage drop being as small as 67.7 mV at a current density of 0.5 C for 200 cycles. Due to its unique architecture, dramatically shortened ion/electron diffusion distance, and more unimpeded Li-ion transmission pathways, the current nanostructured LiNi0.6Co0.2Mn0.2O2 cathode enhances the Li-ion diffusion dynamics and suppresses the voltage drop, thus resulting in superior electrochemical performance. [ABSTRACT FROM AUTHOR]