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The sustained penetration of wind and solar generation is conducive to alleviating the energy crisis and environmental pollution. However, the finite capacity of transmission corridor limits the delivery of remote renewables and leads to curtailment. Energy storage plays an important role in renewables accommodation and improving equipment utilization, and shared energy storage can magnify the benefits through a temporal and spatial complementary. This paper proposes an online dispatch approach of energy storage shared by multiple renewable plants. The uncertainty and non-anticipativity issue are addressed via a two-stage decision-making process. The day-ahead scheduling determines the allowable energy and power levels of shared energy storage; the real-time online dispatch decides the wait-and-see strategies of charging and discharging power based on a single-period optimization model constrained by the pre-scheduled bounds. The case study verifies the effectiveness of the proposed method.

The main obstacles to the development of manganese-based oxide anode materials for lithium-ion batteries (LIBs) are inherently low conductivity and sluggish electrochemical kinetics. In this work, we propose a strategy of introducing oxygen vacancies (Vö) on the surface of nanostructure at room temperature and atmospheric pressure to improve the electrochemical performance of anode materials. Porous MnO2 spheroids with 11.2% Vö are fabricated by a ball milling method using commercial electrolytic MnO2. The as-synthesized MnO2 is composed of 20–30 nm nanoparticles. The optimized MnO2 shows an excellent rate capability of 350 mAh g−1 at 6.4 A g−1 and high specific capacity of 1200 mAh g−1 after 650 cycles under 2 A g−1. The boosted electrochemical performance is attributed to the porous hierarchical structure and the appropriate Vö concentration involved in the MnO2. In addition, the enhanced Li+ diffusion coefficient is demonstrated through the kinetics analysis. The approach provides a facile route via tunable Vö concentration for improving the electrochemical performance of manganese-based oxide anode materials for LIBs. Highlight: • The porous MnO2 spheroids with tunable Vö concentrate were synthesized by a ball milling method. • The MnO2 spheroids are composed of 20-30 nm nanoparticles. • The MnO2 spheroids exhibit an excellent rate performance and cycling stability. • The ball mill is facile, environmentally friendly, economical for the mass industrial scale. [ABSTRACT FROM AUTHOR]

Amorphization is considered to be an effective way to enhance the electrochemical performances of electrode materials due to the existence of isotropy and numerous defects. Herein, an amorphous hierarchically structured MnO2/acetylene black (a-MnO2/AB) composite is successfully fabricated via a redox method and subsequent mechanical ball milling. The a-MnO2/AB composite is composed of approximately 300 nm flower-like amorphous MnO2 submicron spheres and acetylene black particles with a diameter of about 50 nm. The a-MnO2/AB electrode exhibits an initial coulombic efficiency of 73.2%, excellent rate capabilities of 318 mA h g−1 at 9.6 A g−1, and high specific capacity retention of 1300 mA h g−1 after 300 cycles at 1 A g−1. The amorphous structure can provide more channels for rapid lithium-ion transmission due to the disorder and defects, and the ion-diffusion coefficient (∼5 × 10−7 cm2 s−1) is higher than those of crystalline materials. Due to the strong interactions (Mn–O–C bonds) between MnO2 and AB as a result of the ball milling, the composite shows low charge transport resistance and small volume changes during the discharging/charging process. This work provides a facile route for the construction of amorphous hierarchically structured Mn-based oxides as anodes for lithium-ion batteries (LIBs). [ABSTRACT FROM AUTHOR]

Amorphization is considered to be an effective way to enhance the electrochemical performances of electrode materials due to the existence of isotropy and numerous defects. Herein, an amorphous hierarchically structured MnO 2 /acetylene black (a-MnO 2 /AB) composite is successfully fabricated via a redox method and subsequent mechanical ball milling. The a-MnO 2 /AB composite is composed of approximately 300 nm flower-like amorphous MnO 2 submicron spheres and acetylene black particles with a diameter of about 50 nm. The a-MnO 2 /AB electrode exhibits an initial coulombic efficiency of 73.2%, excellent rate capabilities of 318 mA h g -1 at 9.6 A g -1 , and high specific capacity retention of 1300 mA h g -1 after 300 cycles at 1 A g -1 . The amorphous structure can provide more channels for rapid lithium-ion transmission due to the disorder and defects, and the ion-diffusion coefficient (∼5 × 10 -7 cm 2 s -1 ) is higher than those of crystalline materials. Due to the strong interactions (Mn-O-C bonds) between MnO 2 and AB as a result of the ball milling, the composite shows low charge transport resistance and small volume changes during the discharging/charging process. This work provides a facile route for the construction of amorphous hierarchically structured Mn-based oxides as anodes for lithium-ion batteries (LIBs).