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Electrochemical energy storage and conversion devices have greatly advanced our daily life in the past few decades because of the convenience and flexibility they provide. As one of the essential components of energy storage and conversion devices, electrode materials play a crucial role in overall device performances. Conventional material preparation methods, including hydrothermal, chemical vapor deposition, high temperature solid phase methods, etc., are often subject to harsh preparation conditions. Therefore, much simpler and more efficient preparation methods are still sought after by the research community. In recent years, ion exchange (IE) technology, as a novel method for syntheses of nanomaterials, has attracted a great deal of research attention for its great capability in precise structural design and simultaneous regulation of component compositions. Nevertheless, the links among reaction mechanisms, resulting products, and product application performances, have not been fully elaborated. Herein, this review systematically summarizes historical developments of the IE technology for preparation of nanomaterials and relevant reaction mechanisms from both kinetic and thermodynamic perspectives. A detailed summary of recent applications of the IE technology for preparation of a wide variety of nanomaterials and their applications in electrochemical energy storage and conversion devices, including supercapacitors, lithium/sodium-ion batteries, electrolytic water splitting, and hydrogen fuel cells, is presented. In-depth understanding of the IE technology provides better technical approaches for fabrication of high-performance electrode materials. In the final section, an outlook on the IE technology is offered.

In lithium metal batteries (LMBs), the instability of the solid electrolyte interface (SEI) induced lithium dendrites and dead lithium frequently causes low cyclability and serious safety issues. Thereby, a highly stable artificial SEI layer with excellent lithium-ion mobility is desirable for dendrite-free lithium metal (LM) anodes. Herein, a novel clay/cross-linked network polymer-based artificial SEI layer (named as NCL) is prepared via compositing lithiated halloysite nanotubes (Li-HNTs) and cross-linked network polymers. The obtained NCL exhibits a promising Li+ transference number of 0.39, high ionic conductivity of 6.37 × 10-4 S cm−1 at 20 °C and superb mechanical performance. Benefiting these advantages, Li+ can be uniformly and fast plated/stripped under the protection of NCL, effectively suppressing the formation of lithium dendrites. The NCL-protected LM symmetrical cells can be stably cycled for more than 1000 h and 1100 h at 1 mA cm−2 under cycling capacities of 1 mAh cm−2 and 3 mAh cm−2, respectively. The NCL-Li|Cu half-cells present dendrite-free and reversible Li deposition with a high Coulombic efficiency of 99% for 170 cycles at 0.5 mA cm−2. Moreover, the LiFePO4 full-cell successfully achieves a good capacity of 115 mAh g−1 with a sensational capacity retention of 97.5% over 800 cycles at 2C. Additionally, 300 mAh LiNi0.8Co0.1Mn0.1O2-coupled pouch-cells not only can stably circulate more than 50 cycles, but also can reliably function at repetitive mechanical deformation statuses and at different damage conditions. Therefore, this novel hybrid artificial SEI protective layer with desirable properties shed new light on the practical application of high-performance LMBs.

To construct highly stable Lithium (Li) metal batteries (LMBs), a polyurethane-LiF based artificial protective membrane (APM) is evenly coated onto LM anodes by a facile solution casting method. Owning to the good ionic conductivity and mechanical properties, APM acts as a physical protective isolation layer between electrolytes and LM to alleviate electrolyte decomposition and suppress Li dendrites. By applying the APM modification, the electrochemical performance of LM is dramatically improved. The Li | APM-Cu half-cell stably circulates 120 cycles with a high Coulombic efficiency of above 90% at a current density of 1 mA cm−2 and an area capacity of 1 mAh cm−2. The APM-Li based symmetric cell presents an ultralong life span of over 1500 h at an area capacity of 1 mAh cm−2and a current density of 0.5 mA cm−2. In full-cell tests, the APM-Li | LiFePO4 configuration maintains a high specific capacity of 120.4 mAh g−1 after 600 cycles with a superior capacity retention of 97.3% at 2C. Additionally, the extraordinary cyclability of APM-Li | Li4Ti5O12 full-cell demonstrates the effectiveness and versatility of APM. The scanning electron microscopy studies confirm the APM's suppression effects of Li dendrites. Therefore, this work provides a promising and affordable APM modification strategy to redeem highly stable LMBs.

The lithium metal anode has been considered to be an optimal anode material for high-energy-density battery system due to its ultrahigh specific capacity. However, the sharp dendrite growth and infinite volume expansion have significantly impeded its commercial application. Herein, we propose that V2O5 as the lithiophilic substance can be decorated onto 3D stable frameworks to fabricate dendrite-suppressed composite Li metal anodes via a molten Li infusion method. It is demonstrated that the energetic chemical reaction between V2O5 and molten Li together with the capillary effect based on the nanostructure of interconnected V2O5 nanobelt arrays contributes synergistically to the great Li affinity of the V2O5-Ni foam (V2O5-NF) host and facilitate the efficient and uniform intake of molten Li into the 3D framework. Benefitting from the homogeneous Li distribution in the framework, the decreased local current density of the electrode and the stable property of the host, dendrite-free Li stripping/plating behavior and alleviated volume fluctuation have been achieved for the Li-V2O5-NF composite anode. Compared with the bare Li anode, the as-obtained Li-V2O5-NF composite anode exhibits much stable stripping/plating profiles with low overpotential (~18 mV) for ultralong lifespan (1600 h) at a current density of 1 mA cm−2 in symmetric Li/Li cell. Furthermore, outstanding rate capability and long-term cycling performance (78.8% capacity retention after 500 cycles under 2 C) are obtained in full cells when coupled with Li4Ti5O12 (LTO) cathodes, indicating a promising potential for practical application. Moreover, this work demonstrates that using a new lithiophilic material, V2O5, should be an effective method to construct high stable 3D Li metal anode for Li metal battery.

The spinel lithium titanate (Li4Ti5O12, LTO) has attracted special attention for its low cost, stable structure and little safety issue. However, LTO displays a low electronic conductivity, which seriously impedes its practical applications at remarkable rate capability. Herein, to improve the electrochemical properties of LTO, this research constructed a novel composite anode by mixing the GaSn liquid metal (LM) nanoparticles with LTO. The composite anode’s phase structure and morphology were characterized by X-ray diffraction (XRD) and scanning electron microscopy (SEM). The electrochemical data indicate that LM-LTO electrode delivers a better rate capability (52% retention from 10 mA/g to 500 mA/g) as well as long cyclic stability (76% retention after 1000 cycles at 200 mA/g). Therefore, this work opens a new avenue for fabricating better rate performance and safer lithium ions battery.

The thermal stability of rapeseed oil fortified with 3 % sterol linolenate, sterol linoleate, and sterol oleate was investigated using the Rancimat accelerated oxidation method. The results indicated that the sterol ester content in fortified oil displayed positive correlations (P