The advancement of electrochemical energy storage is closely bound up with the breakthrough of controllable fabrication of energy materials. Inspired by a popcorn fabrication from corn raw, herein a unique porous macrocellular carbon composed of cross‐linked nano/microsheets by a powerful puffing of rice precursor is described. The rice is directly puffed with a volume enlargement of ≈20 times when it is instantaneously released from a sealed environment with a high pressure of 1.0 MPa at 200 °C. Interestingly, when metal (e.g., Ni) nanoparticles are embedded in the puffed rice derived carbon (PRC), high‐quality PRC/metal composites are achieved with attractive properties of a high electrical conductivity of ≈7.2 × 104 S m−1, a large porosity of 85.1%, and a surface area of 1492.2 m2 g−1. The PRC/Ni are employed as a host in lithium–sulfur batteries. The designed PRC/Ni/S electrode exhibits a high reversible capacity of 1257.2 mA h g−1 at 0.2 C, a prolonged cycle life (821 mA h g−1 after 500 cycles), and enhanced rate capability, much better than other counterparts (PRC/S and rGO/S). The excellent properties are attributed to the advantages of PRC/Ni network with a high electrical conductivity, strong adsorption/blocking ability for polysulfides, and interconnected porous framework.
Lithium (Li) metal is considered as one of the most promising anode materials for next‐generation high‐energy‐density storage systems. However, the practical application of Li metal anode is hindered by interfacial instability and air instability due to the highly reactivity of Li metal. Unstable interface in Li metal batteries (LMBs) directly dictates Li dendrite growth, “dead Li” and low Coulombic efficiency, resulting in inferior electrochemical performance of LMBs and even safety issues. In addition, its sensitivity to ambient air leads to the severe corrosion of Li metal anode, high requirements of production and storage, and increased manufacturing cost. Plenty of efforts in recent years have overcome many bottlenecks in these fields and hastened the practical applications of high‐energy‐density LMBs. In this review, we focus on emerging methods of these two aspects to fulfill a stable and low cost electrode. In this perspective, design artificial solid electrolyte interphase (SEI) layers, construct three‐dimensional conductive current collectors, optimize electrolytes, employ solid‐state electrolytes, and modify separators are summarized to be propitious to ameliorate interfacial stability. Meanwhile, ex situ/in situ formed protective layers are highlighted in favor of heightening air stability. Finally, several possible directions for the future research on advanced Li metal anode are addressed.
Inspired by high theoretical energy density (~2600 W h kg−1) and cost‐effectiveness of sulfur cathode, lithium–sulfur batteries are receiving great attention and considered as one of the most promising next‐generation high‐energy‐density batteries. However, over the past decades, the energy density and reliable safety levels as well as the commercial progress of lithium–sulfur batteries are still far from satisfactory due to the disconnection and huge gap between fundamental research and practical application. Therefore, it is highly necessary to revisit the scientific issues for the industrial applications of lithium–sulfur batteries. In this review, we focus on discussing the impact of design parameters (such as compaction density, sulfur loading, and electrolyte/sulfur ratio) on the electrochemical performance of lithium–sulfur batteries and corresponding inherent relationship and rules between them. We also propose the practical design rules of advanced sulfur electrodes. Moreover, safety hazard in respect of electrolyte, separator, and lithium metal anode is also illustrated in detail. With the target of paving the way for practical application of lithium–sulfur batteries, feasible solutions and strategies are brought up to address the aforementioned problems. Finally, we will discuss the current challenges and future research chance of lithium–sulfur batteries.