High-Capacity Anode Materials for All-Solid-State Lithium Batteries

Abstract

This mini review article summarizes the recent progress of the all-solid-state lithium ion batteries (LIBs) with high-capacity anodes. Although the theoretical capacity of silicon (Si) is exceptionally high, the large volume change during cycling is a severe drawback for practical applications. The volume change of the active materials leads to mechanical degradation and electrical contact loss, resulting in a poor cycling performance. Recently, the number of reports about Si anodes in liquid electrolytes has significantly increased, leading to the better understanding of the electrochemical performances of Si. For the realization of the LIBs with a high capacity and safety, highcapacity alloy anodes are highly required to be used in all-solid-state batteries. However, at the present stage, research studies of high-capacity anodes with solid electrolytes are scarce compared to the vast amount of reports using liquid electrolyte. The selection of solid electrolytes is also a key factor for the stable performance of high-capacity anodes in the all-solid-state batteries, while previous studies on Si anodes have mainly focused on the fabrication of the hollow structured anodes for reducing their volume expansion. This review will provide some reports about the cycling properties of highcapacity anodes in the all-solid-state batteries and the solid electrolyte interface (SEI) formation at the anode interface of solid electrolytes. The potential of the high-capacity anodes for practical applications in all-solid-state batteries will be discussed.

Development of High‐Energy Anodes for All‐Solid‐State Lithium Batteries Based on Sulfide Electrolytes

“…[1] In contrast to the tremendous efforts in developing high-capacity Si anodes for Li-ion batteries, the conversion of well-developed Si technologies from LIB systems into all-solid-state batteries is at an initial stage and the reported research on Si-anodes for sulfide all-solid-state batteries is scarce. [61] The degradation of Si-anodes is caused by drastic volume expansion (around 360 % for Li 4.4 Si), [62] pulverization, cracking, and huge stress generation, which result from the lithiation/delithiation of Si, and has a series of severe destructive consequences such as: 1) deterioration of electrode structural integrity due to repeated pulverization during discharge/charge processes; 2) disconnection between electrode and current collector induced by the interfacial stress; 3) continuous consumption of lithium ions during the continuous formation-breaking-reformation of the SEI layer. Commonly reported approaches for developing Si anodes for sulfide ASSBs can be categorized as material engineering (size control, modification of surface and morphology, thin films, and alloying) or system optimization (applied pressure, composite anodes with advanced binders/ conductive materials and cut-off voltage).…”

“…Popular methods to mitigate the capacity degradation of Si anodes are nanostructuring, combining Si with carbon composites, utilizing functional binders, and applying electrolyte modifications [1] . In contrast to the tremendous efforts in developing high‐capacity Si anodes for Li‐ion batteries, the conversion of well‐developed Si technologies from LIB systems into all‐solid‐state batteries is at an initial stage and the reported research on Si‐anodes for sulfide all‐solid‐state batteries is scarce [61] …”

The Role of Critical Raw Materials for Novel Strategies in Sustainable Secondary Batteries

“…[ 16 ] Additionally, battery chemistries involving polyvalent cations such as divalent Mg 2+ and Zn 2+ and trivalent Al 3+ are especially interesting as multivalent ions increase the numbers of electrons involved in the electrochemical process, leading to larger capacity values. [ 17 ] Other approaches being investigated are high capacity battery materials (e.g., modified Si anodes [ 18 ] ) and electrolyte modifications to achieve high‐voltage liquid electrolyte (LE) [ 19 ] or cross‐linked single‐ion conducting polymer gels which facilitate smooth platting/stripping processes. [ 20 ] In addition to safety concerns, the depletion of the cobalt and nickel reserves and the corresponding price increase the urge for alternative battery types.…”

Li alloy anodes for high-rate and high-areal-capacity solid-state batteries

“…As a result, there is growing interest in using alloys as anodes for SSBs, i.e., using alloying/dealloying instead of plating/stripping processes for lithium storage. [30][31][32][33][34][35][36][37][38][39] Alloy anodes, such as Si, Sn, and Al, have been widely studied in conventional lithium-ion batteries. 40 Even though alloy anodes have lower capacities and slightly higher voltages than Li metal anodes, the energy density, especially the volumetric energy density, of SSBs using alloy anodes can be comparable to or higher than that of conventional lithium-ion batteries.…”