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Page 2 of 30 Yoon et al. Energy Mater 2024;4:400063 https://dx.doi.org/10.20517/energymater.2023.146

INTRODUCTION
The increasing demand for sustainable energy storage has driven research into high-performance battery
[1-5]
technologies . Lithium-ion batteries (LIBs) currently dominate the secondary battery market but are
anticipated to face limitations in the near future owing to unevenly distributed Li reserves and the depletion
of Li resources. To address these concerns, new energy storage system (ESS) technologies, such as sodium-
(SIBs) [6-10] and potassium-ion batteries (PIBs) [10-16] , have emerged as secondary battery systems that utilize Na
and K as charge carriers. Because Na and K belong to the same elemental group as Li, they undergo
+
electrochemical reactions similar to Li (-3.04 vs. Li /Li). Consequently, they offer advantages in terms of
adoption in LIB systems, including electrode material selection and analytical methods. Additionally, Na
and K are abundantly available, inexpensive, and have standard electrode potentials similar to Li
(Na: -2.71 vs. Na /Na, K: -2.93 vs. K /K). However, owing to safety concerns regarding liquid-electrolyte-
+
+
based systems [17-19] , all-solid-state LIBs (ASSLIBs) are regarded as next-generation battery technologies
owing to the utilization of solid electrolytes, which are more mechanically strong and non-flammable
compared to typical carbonate-based liquid electrolytes. ASSLIBs can suppress thermal runaway and deliver
higher energy densities than LIBs by eliminating the need for separators and replacing fire-related safety
devices [20,21] .

Enhancing high-performance anode materials remains a critical challenge. Carbonaceous anode materials
(mainly graphite) have long been used in LIBs owing to their cycling stabilities and low costs . However,
[17]
high-performance anodes need to overcome the inherent limitations of the low theoretical capacities and
sluggish rate capabilities of carbonaceous anode materials. Similarly, high-performance anode materials for
SIBs and PIBs are also urgently needed [22-24] . Hard carbon is the preferred SIB anode material because the
interlayer spacing of graphite is too narrow to accommodate Na ions. However, hard carbon has a limited
reversible capacity with a poor initial Coulombic efficiency (ICE). Although various carbonaceous anode
-1
materials can be used in PIBs, they exhibit low reversible capacities (279 mAh g , KC ). Similarly, during the
8
initial stages of ASSLIB research, a solid electrolyte with a high mechanical strength physically inhibited the
growth of Li dendrites, thereby facilitating the direct utilization of lithium metal. However, recent studies
have found that the direct use of lithium metal results in self-destructive properties [19,20] that also promote
the decomposition of the solid electrolyte at the interface, leading to the growth of Li dendrites.
Furthermore, graphite anodes also accelerate solid-electrolyte deterioration due to their low reaction
3
+
potentials (0-0.2 V vs. Li /Li) and high electrical conductivities (~10 S/m) [25,26] . Therefore, research into
high-performance anode materials applicable to LIBs, SIBs, PIBs, and ASSLIBs with high capacities, long-
term cycling stabilities, fast rate capabilities, and that do not form dendrites is required.

Antimony (Sb) is a promising alternative high-performance next-generation anode material candidate that
simultaneously meets the aforementioned requirements for LIBs, SIBs, PIBs, and ASSLIBs. Figure 1 shows
that an Sb anode exhibits the same high theoretical capacity of 660 mAh g [Table 1 and Figure 1A] in alkali
-1
metal-ion batteries (AIBs) [9-16,27-39] . In particular, the Sb anode offers a high theoretical volumetric capacity
-3 [27-31]
-3
(Table 1 and Figure 1B, 4,420 mA h cm ) , which is attributable to the high density of Sb (6.70 g cm at
ambient temperature). Although the theoretical capacity of Sb is high, Sb anodes are poorly cyclable owing
to excessive volume change experienced during cycling (Table 1 and Figure 1C; Li Sb: 134%, Na Sb: 291%,
3
3
and K Sb: 406%). To address the issue of Sb anodes, researchers have explored various strategies based on a
3
comprehensive understanding of their electrochemical reaction mechanisms in AIBs and ASSLIBs. Among
numerous studies and strategies, this review focuses on three main strategies for improving the performance
of Sb-based anodes. First, solid electrolyte interface (SEI) layer control is a strategy for optimizing the
construction and composition of the SEI layer that develops on the electrode surface during cell operation.
An ideal SEI layer is chemically stable, ion-conductive, and inhibits excessive electrolyte decomposition,