In this work, we show an effective ultrasonication-assisted self-assembly method under surfactant solution for a high-rate capable rGO-wrapped LiNi 0.6 Co 0.2 Mn 0.2 O 2 (Ni-rich cathode material) composite. Ultrasonication indicates the pulverization of the aggregated bulk material into primary nanoparticles, which is effectively beneficial for synthesizing a homogeneous wrapped composite with rGO. The cathode composite demonstrates a high initial capacity of 196.5 mAh/g and a stable capacity retention of 83% after 100 cycles at a current density of 20 mA/g. The high-rate capability shows 195 and 140 mAh/g at a current density of 50 and 500 mA/g, respectively. The high-rate capable performance is attributed to the rapid lithium ion diffusivity, which is confirmed by calculating the transformation kinetics of the lithium ion by galvanostatic intermittent titration technique (GITT) measurement. The lithium ion diffusion rate ( D Li ) of the rGO-wrapped LiNi 0.6 Co 0.2 Mn 0.2 O 2 composite is ca . 20 times higher than that of lithium metal plating on anode during the charge procedure, and this is demonstrated by the high interconnection of LiNi 0.6 Co 0.2 Mn 0.2 O 2 and conductive rGO sheets in the composite. The unique transformation kinetics of the cathode composite presented in this study is an unprecedented verification example of a high-rate capable Ni-rich cathode material wrapped by highly conductive rGO sheets.

Sulfur is a prospective material for next-generation batteries with high theoretical capacity, but its drawbacks hinder its commercialization. To overcome the low conductivity of natural sulfur and the shuttle effect of lithium polysulfide, the study proposes a novel sulfur film coated with three-dimensional nitrogen and cobalt-codoped polyhedral carbon wrapped on a multiwalled carbon nanotube sponge (3D-S@NCoCPC sponge) composite as a high-performance cathode material for rechargeable lithium–sulfur batteries. The interconnected conductive carbon network with abundant pores provides more room for the homogeneous distribution of sulfur within the composite and creates a favorable pathway for electrolyte permeability and lithium-ion diffusion. Moreover, the strong interaction between cobalt and lithium polysulfides leads to efficient suppression of the shuttle effect. In addition, the homogeneous distribution of sulfur and cobalt within the composite enhances electronic transfer for the conversion reaction of sulfur. As expected, the cathode with a high sulfur content of 77.5 wt % in the composite achieved a high initial discharge capacity of 1192 mA h g–1 and high Coulombic efficiency of 99.98% after 100 cycles at 100 mA g–1 current density. Stable performance was achieved with 92.9% capacity retention after 200 cycles at 1000 mA/g current density.

All-solid-state batteries have gained significant attention as promising candidates to replace liquid electrolytes in lithium-ion batteries for high safety, energy storage performance, and stability under elevated temperature conditions. However, the low ionic conductivity and unsuitability of lithium metal in solid polymer electrolytes is a critical problem. To resolve this, we used a cubic garnet oxide electrolyte (Li7La3Zr2O12 – LLZO) and ionic liquid in combination with a polymer electrolyte to produce a composite electrolyte membrane. By applying a solid polymer electrolyte on symmetric stainless steel, the composite electrolyte membrane shows high ionic conductivity at elevated temperatures. The effect of LLZO in suppressing lithium dendrite growth within the composite electrolyte was confirmed through symmetric lithium stripping/plating tests under various current densities showing small polarization voltages. The full cell with lithium iron phosphate as the cathode active material achieved a highest specific capacity of 137.4 mAh g−1 and a high capacity retention of 98.47% after 100 cycles at a current density of 50 mA g−1 and a temperature of 60°C. Moreover, the specific discharge capacities were 137 and 100.8 mAh g−1 at current densities of 100 and 200 mA g−1, respectively. This research highlights the capability of solid polymer electrolytes to suppress the evolution of lithium dendrites and enhance the performance of all-solid-state batteries.

All‐solid‐state Li batteries (ASSLBs) are considered suitable candidates to replace conventional batteries utilizing liquid electrolytes. However, the applications of this type of batteries are limited owing to their narrow operating temperature range, low ionic conductivity, poor long‐term stability, and complex production process. Herein, a simple approach that combines all potential battery candidates that have been investigated over the last few years, including polyethylene oxide (PEO), Li7La3Zr2O12 (LLZO), succinonitrile (SN), and Li salt (LiTFSI), is employed to solve the limitations of ASSLBs. LLZO codoped with Al3+ and Nb5+ (NAL) is synthesized at a low temperature using a modified sol‐gel Pechini method. NAL, along with SN, plays a critical role in improving the performance of the resultant solid polymer electrolyte, which can be operated at room temperature. The integrated electrolyte PEO/LiTFSI‐SN‐NAL (PLS‐NAL) delivers a high ionic conductivity of 3.09 × 10−4 S cm−1 and an excellent Li‐ion transference number of 0.75 at room temperature. ASSLBs combining LiFePO4 and PLS‐NAL exhibit excellent cycling stability at both room temperature and 45 °C with a high capacity retention of ≈90% after 200 cycles and cycle life of up to 400 cycles.

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