Dendrite growth of lithium (Li) metal anode severely hinders its practical application, while the situation becomes more serious at low temperatures due to the sluggish kinetics of Li-ion diffusion. This perspective is intended to clearly understand the energy chemistry of low-temperature Li metal batteries (LMBs). The low-temperature chemistries between LMBs and traditional Li-ion batteries are firstly compared to figure out the features of the low-temperature LMBs. Li deposition behaviors at low temperatures are then discussed concerning the variation in Li-ion diffusion behaviors and solid electrolyte interphase (SEI) features. Subsequently, the strategies to enhance the diffusion kinetics of Li ions and suppress dendrite growth including designing electrolytes and electrode/electrolyte interfaces are analyzed. Finally, conclusions and outlooks are drawn to shed lights on the future design of high-performance low-temperature LMBs.

Oxygen reduction reaction (ORR) constitutes the core process of many energy storage and conversion devices including metal–air batteries and fuel cells. However, the kinetics of ORR is very sluggish and thus high-performance ORR electrocatalysts are highly regarded. Despite recent progress on minimizing the ORR half-wave potential as the current evaluation indicator, in-depth quantitative kinetic analysis on overall ORR electrocatalytic performance remains insufficiently emphasized. In this paper, a quantitative kinetic analysis method is proposed to afford decoupled kinetic information from linear sweep voltammetry profiles on the basis of the Koutecky–Levich equation. Independent parameters regarding exchange current density, electron transfer number, and electrochemical active surface area can be respectively determined following the proposed method. This quantitative kinetic analysis method is expected to promote understanding of the electrocatalytic effect and point out further optimization direction for ORR electrocatalysis.

Aqueous zinc–air batteries (ZABs) are highly regarded as a promising electrochemical energy storage device owing to high energy density, low cost, and intrinsic safety. The employment of seawater to replace the currently used deionized water in electrolyte will bring great economic benefits and broaden the application occasions of ZABs. However, ZABs using seawater-based electrolyte remain uninvestigated without an applicable cathode electrocatalyst or a successful battery prototype. Herein, seawater-based electrolyte is successfully employed in ZABs with satisfactory performances. The influence of chloride anions on the cathode electrocatalytic reactivity and battery performance is systemically investigated. Both noble-metal-based and noble-metal-free electrocatalysts are applicable to the chloride-containing alkaline electrolyte. Further evaluation of ZABs with seawaterbased electrolyte demonstrates comparable battery performances with the conventional electrolyte in terms of polarization, capacity, and rate performance. This study demonstrates a successful prototype of seawater-based ZABs and enlightens the utilization of natural resources for clean and sustainable energy storage.

Thin artificial solid electrolyte coatings are effective to enhance the electrochemical performances and safety issues of lithium (Li) metal anode. However, massive and efficient fabrication of artificial protection layers on Li metal anode surface remains challenging. Herein, we describe a sandwiched Li metal anode fabricated through a continuous roll to roll calendering method to implant a thin and large-area carbon layer on Li metal anode surface at room temperature. Specifically, a carbon layer (~ 3 μm in thickness) can be entirely grafted from Cu substrate to 50 μm Li belt surface due to the stickiness of metallic Li. The carbon layer not only plays a critical role in providing rich nucleation sites for Li plating, but more importantly diminishes the metallurgical nonuniformity effects (slip lines) on stripping. Therefore, even Li plating/stripping morphologies are achieved and the as-obtained sandwiched Li/C composite anodes exhibit improved cycling stability both in Li | LiFePO₄ and Li | S coin cells and pouch cells. This continuous roll to roll calendering strategy opens a new avenue for grafting various thin artificial protection layers on Li metal surface for safe rechargeable batteries.

Lithium–sulfur (Li–S) batteries are receiving increasing attention because of their high theoretical energy density and the natural abundance of S. However, their practical applications are impeded by the low areal S loading in the cathode and the fatal Li dendrites in the anode of the Li-S cells, which yield an inferior practical energy density and introduce safety concerns, respectively. In this review, we focus on an emerging approach—the nanostructured current collector—to overcome these two critical challenges for Li-S batteries. We describe the general attributes of nanostructured current collectors and examine how these attributes enhance the S utilization with a high S loading and suppress the Li dendrites by regulating the Li-deposition behavior. We present various assembly blocks that have been used for the construction of advanced nanostructured current collectors to build better S cathodes and Li anodes. Finally, we investigate the current challenges and possible solutions regarding the practical applications of nanostructured current collectors in Li-S batteries.