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LiNi0.5Co0.2Mn0.3O2 is becoming the dominating cathode material in lithium ion batteries, which have degradation issues after cycling due to Li+ loss and phase changes. But there is no effective method to solve this problem. Here, we offer an innovative method to regenerate degraded nickel-manganese-cobalt cathode particles to obtain new active particles. The results show that the regeneration materials display the discharge capacities of 162.0 mAh/g at 0.1 C. When cycled at 1 C, a highly reversible discharge capacity of 128.6 mAh/g can be obtained after 100 cycles with capacity retention of 91.9%, which is comparable with commercial LiNi0.5Co0.2Mn0.3O2.

Porous carbon sheet (PCS) was prepared by reduction reaction between NaBH4 and the in-situ formed CO2 gas from the thermal-decomposition of NaHCO3 under inert atmosphere. During this preparation process, NaHCO3 also could be used as the activation agent and increases the specific surface area of carbon materials. The obtained PCS has a specific surface area of 828 m2/g. At a current density of 0.5 A/g, the specific capacitance of the PCS electrode is 201 F/g. Furthermore, the PCS electrode exhibits excellent rate capability (80% capacitance retention at 15 A/g) and superior cycling stability. These results suggest a facile and environmental benign method to prepare economical and high quality porous carbon sheet materials for energy storage applications. Keywords: Carbon materials, Porous materials, Carbon dioxide, NaBH4, Supercapacitor

In this work, nitrogen doped clews-like carbon materials were successfully fabricated through hydrothermal polymerization method, followed by post treatment that integrated the carbonization, activation and post-nitrogen doping into one process. This preparation method can form particular hierarchical porous structure without using any sacrificial templates. The experimental results show that the nitrogen doped clews-like hierarchical porous carbon materials possess a relatively high specific surface area of 815 m2/g with the nitrogen content of 10.58 at%. The electrochemical properties show that the resulting sample delivers 258 F/g at a 0.5 A/g and excellent capacity retention of 79% at 20 A/g. After conducting 10,000 charge-discharge cycles at 10 A/g, the capacitance retention of 98.3% is achieved. These intriguing results demonstrate that the obtained nitrogen doped clews-like carbon materials will be promising electrode materials for supercapacitor and other energy storage devices.

The spinel Li4Ti5O12 (LTO) has been doped by Ca2+ via a solid-state reaction route, generating highly crystalline Li3.9Ca0.1Ti5O12 powders in order to improve the electrochemical performance as an anode. The structure changes, morphologies, and electrochemical properties of the resultant powders have been characterized by X-ray diffraction (XRD), scanning electron microscopy (SEM), and cyclic voltammetry (CV), respectively. Crystal structure and composition were analyzed, and results were obtained with various tests of LTO. Electrochemical measurements revealed that Li3.9Ca0.1Ti5O12 anodes exhibit better rate capability, better cycling stability, and a higher specific capacity than pure LTO anodes.

The highly uniformed hybrid carbon material has been prepared by in-situ growth carbon nanotubes (CNTs) from metal organic frameworks, with the cobalt species as the catalyst for CNTs growth and dicyandiamide (DICY) as a sacrificial agent for the formation of graphitic carbon. The CNTs with extraordinary conductivity supply more electron transport to the cathode and make much more sense in enhancing the rate performance of the sulfur cathode. In the matrix, cobalt nanoparticles and heteroatom nitrogen can help in immobilizing sulfur species, leading to the improvement of polysulfide shutting. Moreover, the increased specific surface area and mesoporous channel enhance the sulfur loading and facilitate electrolyte diffusion. On integrating these fascinating benefits into one electrode material, as a result, the hybrid composite (CNT@Co N C/S) cathode presents a high initial capacity of 1316.1 mAh/g at the current rate of 0.1C. Even at high current rate of 5C, a decent capacity of 620.7 mAh/g can still be achieved. The capacity of hybrids materials can be maintained at 970 mAh/g after 500 cycles at 0.2C, and a capacity retention of 79.8%, revealing it great potential for energy storage application.

Uncontrollable Li dendrite growth and unstable SEI during repetitive Li deposition–dissolution processes severely impede the practical application of lithium metal batteries (LMBs). Herein, we create a novel artificial SEI layer by using liquid metal with self-healing property. The liquid metal could effectively facilitate the stable SEI layer formation by virtue of its self-healing property and regulate Li ion flus and inhibit the Li dendrite growth in the deposition process of Li. Electrochemical studies show that the LMNP-Li|LTO full-cell exhibits a superb rate capability and an excellent long-term cycling stability. This work offers a novel approach to achieve a stable Li metal anode with long cycle life.

Lithium-ion batteries (LIBs) technology have been widely utilized as these batteries show great promise as power sources in our life. However, the commercial anode is mainly carbon materials which facing safety issues owing to a low Li-intercalation potential. The spinel Li4Ti5O12 (LTO) has attracted special attention for its structural changes lightly, better safety performance and stable cycle reversibility. Herein, we increased the electronic conductivity of LTO via improving the transport properties of the material with sucrose as carbon sources. The modified LTO with sucrose were successfully fabricated and found to exhibit better electronic conductivity. XRD results showed that all the major diffractions from the spinel structure of LTO can be found in the modified LTO such as (1 1 1), (3 1 1), (4 0 0) but there are no observations of the carbon diffraction peaks. Electrochemical impedance spectroscopy (EIS) data shows modified LTO resistance was nearly one third of the standard LTO value, which indicates modifying LTO with sucrose is a promising approach to prepare the high performance LTO anode. Keywords: Lithium-ion batteries, Li4Ti5O12, Electronic conductivity, Sucrose