Impact of Morphological Dimensions in Carbon‐Based Interlayers on Lithium Metal Anode Stabilization

Abstract

Lithium metal batteries (LMBs) offer high energy density and promise as a future technology. Yet, their adoption is hindered by safety concerns and cycle life stability, arising from Li dendrite formation, solid electrolyte interphase instability, and volume changes during cycling. In response to these challenges, carbon‐based materials have been utilized as an artificial interface layer for modifying the surface of copper current collector in LMBs. Among the diverse carbon‐based materials, 0D carbon, with its high specific surface area, is advantageous for enhancing Li ion transport rates and ensuring uniform current distribution. 1D carbon structures foster a network that facilitates Li ion diffusion, while 2D carbon establishes a protective layer, mitigating side reactions. 3D carbon structures promote Li deposition within their internal cavities, effectively controlling volume fluctuations. With this understanding, this review delves into the latest advancements in carbon‐based materials for modifying copper current collectors. It offers a detailed exploration of how each dimension of carbon‐based materials contributes to regulating Li deposition. Furthermore, the ongoing challenges and potential avenues in the development of carbon‐modified copper current collectors for LMBs are spotlighted, aiming to provide insightful guidance for the design of anode‐free Li metal batteries.

Stabilizing Lithium-Metal Host Anodes by Covalently Binding MgF2 Nanodots to Honeycomb Carbon Nanofibers

“…4,5 To date, various attempts have been made to regulate the Li plating/stripping performance, focusing on avoiding uncontrolled dendrite formation and volume expansion. 6 Carbon hosts with large specific surface areas have emerged as a promising strategy, as they can decrease the local current density and thus regulate the uniform nucleation and deposition of Li. 7−10 This leads to more reversible Li metal anodes with high energy density.…”

“…The potential of Li metal as the anode material for next-generation high-energy batteries has been widely recognized, given its ultrahigh theoretical capacity (3860 mAh g –1 ) and low electrochemical potential (−3.04 V vs the standard hydrogen electrode). − However, the challenges associated with Li dendrites’ notorious growth and the uncontrolled volume expansion during the repeated Li plating/stripping process are significant. These issues can lead to short circuits and even explosions, making the practical application of Li metal anodes a daunting task. , To date, various attempts have been made to regulate the Li plating/stripping performance, focusing on avoiding uncontrolled dendrite formation and volume expansion . Carbon hosts with large specific surface areas have emerged as a promising strategy, as they can decrease the local current density and thus regulate the uniform nucleation and deposition of Li. − This leads to more reversible Li metal anodes with high energy density. − To further improve this approach, lithiophilic nanospecies (substances that attract Li ions) are typically introduced into the carbon host to enhance the affinity for Li. − Several lithiophilic nanospecies, including Ag, Zn, and Mg, have been studied for this purpose, leading to improvements in electrochemical performance. − Unfortunately, a critical challenge remains: the structural integrity of these lithiophilic sites when merely attaching them physically without any chemical bonding.…”

Advances in Selenium Sulfides Cathodes for Lithium/Selenium–Sulfur Batteries

“…Under the imperative of the Double Carbon Target to reduce greenhouse gas emissions and enhance responsiveness to climate change, there’s a growing need to shift focus away from fossil fuels toward high-performance energy storage. − Electrochemical energy storage stands out as a vital system among energy storage technologies due to its wide range of applications grounded in various redox reactions or Faraday effects. − Commercial lithium-ion batteries have achieved tremendous success in powering portable electronics but fall short of meeting the burgeoning energy demands, even at their full potential. − In the quest for advanced electric energy storage solutions, Li–S batteries have surfaced as an extremely viable option by virtue of their elevated theoretical energy density. − The sulfur cathode offers numerous advantages such as cost-effectiveness, abundance, nontoxicity, and high specific capacity. − However, its insulating nature and the challenges associated with polysulfides intermediates dissolution and volume expansion during the conversion of sulfur to Li 2 S result in limitations like low sulfur utilization, restricted rate performance, rapid capacity decay, and the notorious shuttle effect. − This shuttle effect triggers a parasitic reaction that causes a continuous loss of active substances, severely reducing the Coulombic efficiency and cycling stability. − Elemental selenium has surfaced as an alternative to sulfur because of its electrochemical properties and position in the periodic table with sulfur. Although Li–Se batteries have a marginally lower theoretical weight-based energy density compared to Li–S variants, they make up for it with an impressive theoretical volume-based energy density of 3254 mAh cm –3 , attributed to their high density (4.8 g cm –3 ). − A distinguishing feature of selenium is its semiconductive characteristics, which offer an electronic conductivity that is approximately 20 orders of magnitude greater than sulfur, along with a high discharge voltage. − These attributes contribute to greater lithium activity, better active materials utilization, superior rate performance, and increased overall energy density. − Nonetheless, the limited availability and consequent high cost of selenium on Earth, along with persistent challenges related to the shuttle effect and capa...…”

Advanced engineering strategies for Li2S cathodes in lithium–sulfur batteries

“…[28][29][30] In contrast to sulfur, the Li 2 S cathode can be paired with Li-free anodes like graphite, silicon, or tin, thus removing the necessity for troublesome lithium metal anodes. [31][32][33] Li 2 S also has a mass-specic capacity of 1166 mA h g −1 , a volume-specic capacity of 1937 mA h cm −3 , and a theoretical specic energy of 1166 W h kg −1 . 34 These values are nearly equivalent to those of the sulfur cathode.…”