Multidimensional Germanium‐Based Materials as Anodes for Lithium‐Ion Batteries

Abstract

Metallic germanium is an ideal anode for lithium-ion batteries (LIBs), owing to its high theoretical capacity (1624 mA h g(-1) ) and low operating voltage. Herein, we highlight recent advances in the development of Ge-based anodes in LIBs, although improvements in their coulombic efficiency (CE), capacity retention, and rate performance are still required. One of the major concerns facing the development of Ge anodes is the controlled formation of microstructures. In this Focus Review, we summarize Ge-based materials with different structural dimensions, that is, zero-dimensional (0D), one-dimensional (1D), two-dimensional (2D), three-dimensional (3D), and even monolithic and macroscale structures. Moreover, the design of Ge-based oxide materials, as an effective route for achieving higher Li-storage capacities and cycling performance, is also discussed. Finally, we briefly summarize new types of Ge-based materials, such as ternary germanium oxides, germanium sulfides, and germanium phosphides, and predict that they will bring about a reformation in the field of LIBs.

Binder-free nanostructured germanium anode for high resilience lithium-ion battery

“…Li-alloying materials [6,11] and in particular Group IV-A elements including silicon (Si), germanium (Ge), and tin (Sn) -are considered promising anodic candidates for the next generation of LIBs [12]. Compared to the conventional graphite anode, which has a theoretical specific capacity of 372 mAh g − 1 , these alloying materials provide theoretical specific capacities of 4200 mAh g − 1 [13][14][15], 1624 mAh g − 1 [16][17][18], and 994 mAh g − 1 [19,20] when lithiated up to Li 22 Si 5 , Li 22 Ge 5 , and Li 22 Sn 5 phases, respectively. Ge is characterized by remarkable properties in terms of intrinsic electrical conductivity and lithium ion diffusivity, respectively 10,000 times [21] and 400 times [22] higher than Si, hence making Ge an excellent candidate for high performance batteries.…”

Group IVA Element (Si, Ge, Sn)‐Based Alloying/Dealloying Anodes as Negative Electrodes for Full‐Cell Lithium‐Ion Batteries

“…Among the diverse new types of anode materials, Group IVA elements, including silicon (Si), germanium (Ge), and tin (Sn), are regarded as promising alternative candidates for the next‐generation LIBs. Si, Ge, and Sn own high theoretical capacities of 4200 mAh g −1 , 1625 mAh g −1 , and 994 mAh g −1 for full lithiation to the Li 22 Si 5 , Li 22 Ge 5 , and Li 22 Sn 5 phases, respectively, based on alloy reactions between the respective elements and lithium, which are significantly different from the intercalation mechanism of graphite. Moreover, a low working potential (0.3–0.6 V) makes the advantages of these materials more prominent compared with insertion‐ (such as TiO 2 ) and conversion‐type (such as Fe 2 O 3 ) anodes when paired with a cathode to enable higher energy density batteries .…”

Electrochemical Behavior of Reduced Graphene Oxide Supported Germanium Oxide, Germanium Nitride, and Germanium Phosphide as Lithium-Ion Battery Anodes Obtained from Highly Soluble Germanium Oxide

“…Lv et al calculated that 44.4–44.6% of Li 2 O matrix participates in the reverse alloying during cycling at 100 mA g −1 due to intimate contact between graphene layers and GeO x nanoparticles [ 51 ]. However, the significant irreversible capacity loss of the first cycle remains a severe problem for germanium oxide anode materials [ 52 ].…”