Toward High‐Energy‐Density Lithium Metal Batteries: Opportunities and Challenges for Solid Organic Electrolytes

Abstract

The ORCID identification number(s) for the author(s) of this article can be found under https://doi.org/10.1002/adma.201905219.With increasing demands for safe, high capacity energy storage to support personal electronics, newer devices such as unmanned aerial vehicles, as well as the commercialization of electric vehicles, current energy storage technologies are facing increased challenges. Although alternative batteries have been intensively investigated, lithium (Li) batteries are still recognized as the preferred energy storage solution for the consumer electronics markets and next generation automobiles. However, the commercialized Li batteries still have disadvantages, such as low capacities, potential safety issues, and unfavorable cycling life. Therefore, the design and development of electromaterials toward high-energy-density, long-life-span Li batteries with improved safety is a focus for researchers in the field of energy materials. Herein, recent advances in the development of novel organic electrolytes are summarized toward solid-state Li batteries with higher energy density and improved safety. On the basis of new insights into ionic conduction and design principles of organic-based solid-state electrolytes, specific strategies toward developing these electrolytes for Li metal anodes, high-energy-density cathode materials (e.g., high voltage materials), as well as the optimization of cathode formulations are outlined. Finally, prospects for next generation solid-state electrolytes are also proposed.

Review of Emerging Concepts in SEI Analysis and Artificial SEI Membranes for Lithium, Sodium, and Potassium Metal Battery Anodes

“…It is consistently argued that a primarily inorganic SEI structure is more advantageous than a primarily organic SEI for metal cycling stability. [12,13] However, recent studies point to the potential of tuned organic layers in preventing dendrites. Wang and co-workers [166] reported a reactive polymer composite (RPC) based on poly(vinylsulfonyl fluoride-ran-2-vinyl-1,3-dioxolane) (P(SF-DOL))-graphene oxide (GO) nanosheets, obtained by free radical polymerization and blending GO nanosheets in tetrahydrofuran (THF).…”

“…[ 9–11 ] The dominant focus of many reports is on the spatially averaged SEI chemistry. [ 12,13 ] However recent progress brings fourth site‐specific concepts in the SEI analysis, presenting a more nuanced and complex picture of the dynamic SEI versus what has been historically recognized. The motivation for this topical review article is to focus on recent exciting developments in controlling dendrite growth through membranes, which in effect create an artificial SEI layer in place of a natural SEI that is less stable.…”

Structure Code for Advanced Polymer Electrolyte in Lithium‐Ion Batteries

“…[ 12 ] Although the fabrication of GPEs and CPEs system significantly improved the performance of PEs, the replacement of conventional liquid electrolytes by current PEs is still restricted. [ 13,30 ] Thus, in recent years, several studies have focused on the skeleton structure of the polymer matrices, while novel macromolecular chains have been designed and synthesized based on polymer engineering to regulate the electrolyte performance for LIBs. For instance, the regulation of monomer species via copolymerization could not only interrupt the crystallinity of the homopolymer chains, permitting fast ion conduction in more expansive amorphous regions, [ 14 ] but also equip the polymer backbones with extra functionalities, such as mechanical strength, [ 15 ] ion migration capacity, [ 16 ] self‐healing, [ 17 ] flame‐retardant, [ 18 ] or folding specialty.…”

Recent Developments and Challenges in Hybrid Solid Electrolytes for Lithium-Ion Batteries

“…Driven by the growing number of applications and ever increasing use of consumer electronics, significant research effort has been focused on developing improved battery systems and reducing production costs (Fu et al, 2014;Luo et al, 2016;Zhu et al, 2018b,c). Conventional LIBs suffer from potential fire hazards caused by short-circuiting of the battery that may cause thermal runaway (Varzi et al, 2016;Manthiram et al, 2017;Wang X. et al, 2020;. In addition, the high reactivity of liquid electrolytes with the electrodes leads to side reactions and capacity fade over time (Xiao et al, 2020).…”