Power and Energy Commons^™

Asymmetric Electrode-Electrolyte Interfaces For High-Performance Rechargeable Lithium-Sulfur Batteries, Jia Chou, Ya-Hui Wang, Wen-Peng Wang, Sen Xin, Yu-Guo Guo

Journal of Electrochemistry

With a high cell-level specific energy and a low cost, lithium-sulfur (Li-S) battery has been intensively studied as one of the most promising candidates for competing the next-generation energy storage campaign. Currently, the practical use of Li-S battery is hindered by the rapidly declined storage performance during battery operation, as caused by irreversible loss of electroactive sulfide species at the cathode, dendrite formation at the anode and parasitic reactions at the electrode-electrolyte interface due to unfavorable cathode-anode crosstalk. In this perspective, we propose to stabilize the Li-S electrochemistry, and improve the storage performance of battery by designing asymmetric electrode-electrolyte interfaces …

Hydrophobicity Optimization Of Cathode Catalyst Layer For Proton Exchange Membrane Fuel Cell, Hao-Jie Chen, Mei-Hua Tang, Sheng-Li Chen

Journal of Electrochemistry

Hydrophobicity of the cathode catalyst layers (CCLs) crucially determines the performance of proton exchange membrane fuel cells (PEMFCs) by affecting the transports of oxygen and liquid water. In this regard, polytetrafluoroethylene (PTFE) is usually used as a hydrophobic additive to facilitate the oxygen and water transports in CCLs. So far, there remains lacking systematic effort to optimize the addition methods of PTFE in CCLs and the mechanisms behind. In this work, the effects of the approaches for PTFE addition and the distribution of PTFE on the mass transport of oxygen and the proton conduction in CCLs were studied by using …

Synthesis And Evaluation Of Organic Additives For Copper Electroplating Of Interconnects, Yue-Hui Zhai, Yi-Xiao Peng, Yan Hong, Yuan-Ming Chen, Guo-Yun Zhou, Wei He, Peng-Ju Wang, Xian-Ming Chen, Chong Wang

Journal of Electrochemistry

Copper interconnects are essential to the functionality, performance, power efficiency, reliability, and fabrication yield of electronic devices. They are widely found in chips, packaging substrates and printed circuit boards, and are often produced by copper electroplating in an acidic aqueous solution. Organic additives play a decisive role in regulating copper deposition to fill microgrooves, and micro-vias to form fine lines and interlayer interconnects. Generally, an additive package consists of three components (brightener, suppressor, and leveler), which have a synergistic effect of super-filling on electroplating copper when the concentration ratio is appropriate. Many works of literature have discussed the mechanism of …

Effect Of Amine Additives On Thermal Runaway Inhibition Of Sic||Ncm811 Batteries, Bo-Wen Hou, Long He, Xu-Ning Feng, Wei-Feng Zhang, Li Wang, Xiang-Ming He

Journal of Electrochemistry

The high energy density of NCM batteries with high nickel content is a key advantage in replacing fossil fuels and promoting clean energy development, at the same time, is also a fundamental cause of serious safety hazards in batteries. Primary and secondary amines can lead to ring-opening polymerization of common ethylene carbonate electrolytes, resulting in an isolation layer between the cathode and the anode, and improving the thermal safety of the battery. In this work, the safety of batteries is considered both at the material level and at the cell level, based on the chemical reactions between amines and the …

Effects Of Traps On Photo-Induced Interfacial Charge Transfer Of Ag-Tio2: Photoelectrochemical, Electrochemical And Spectroscopic Characterizations, Zhi-Hao Liang, Jia-Zheng Wang, Dan Wang, Jian-Zhang Zhou, De-Yin Wu

Journal of Electrochemistry

In the field of metal-semiconductor composites based plasmon-mediated chemical reactions, a clear and in-depth understanding of charge transfer and recombination mechanisms is crucial for improving plasmonic photocatalytic efficiency. However, the plasmonic photocatalytic reactions at the solid-liquid interface of the electrochemical systems involve complex processes with multiple elementary steps, multiple time scales, and multiple controlling factors. Herein, the combination of photoelectrochemical and electrochemical as well as spectroscopic characterizations has been successfully used to study the effects of traps on the photo-induced interfacial charge transfer of silver-titanium dioxide (Ag-TiO₂). The results show that the increase of surface hydroxyl groups may …

Impact Of Solar Generation On Ieee 9-Bus System, Tasnim Ikra Rahman

Electronic Theses and Dissertations

There has been an increasing interest in renewable energies due to public awareness of the negative effects of fossil fuel-fired electricity generation on the environment, and policies have been enacted requiring progressive reduction of such generation. Due to some favorable characteristics of solar over other renewables, solar power has grown considerably. Integration of solar generation into the existing power grids poses significant challenges. Solar generators' limited reactive power capability can cause several problems, such as significant voltage drops or rises in the system. Therefore, voltage stability is a major concern. This thesis presents an investigation of the voltage characteristics of …

Comparing Current Consistency And Electrical Resistance Of Wearable Photovoltaic Cells Pre- And Post-Laundering And Pre- And Post-Corrosion Resistance Testing Conditions., Amit Talukder

Theses and Dissertations

Photovoltaic(PV) technology is promising due to its natural availability among energy harvesting technologies. There is a growing need for sustainable power sources that can function without being connected to a power source or needing regular battery replacements. Wearable PV cells are gaining popularity in different applications. However, most companies produce wearable PVs for terrestrial applications. Research on wearable PV applications for the marine environment remains limited because these cells suffer from several issues. This research compares commercially sourced wearable PV cells' maximum current consistency and electrical resistance for two testing conditions. The researcher followed standardized methods for these two laundering …

A Method For Economic Expansion Planning Of Transmission Networks Using Heuristic Rules And Non-Linear Optimization Model, Maged Gamal Lotfy, Mahmoud Ali Farrag, Mohamed Shibl Albags, Ahmed Hamdy Khalil

Mansoura Engineering Journal

This paper presents a method for economic planning of transmission networks in an iterative manner. The method is capable of solving large scale networks where the most "worst" new lines are deleted iteratively using heuristic rules. In each iteration, a relatively small size non-linear mathematical Programming model is built to enhance the deletion process. The non-linear model is based on full AC load flow where only the reactive power injected from different available reactive power sources are controlled plus the reference bus voltage magnitude. The deletion process is stopped when the deleting of any line from the rest set of …

Heuristics For Lagrangian Relaxation Formulations For The Unit Commitment Problem, Stephen Opeyemi Fatokun

Doctoral Dissertations

The expansion of distributed energy resources (DER), demand response (DR), and virtual bidding in many power systems and energy markets are creating new challenges for unit commitment (UC) and economic dispatch (ED) techniques. Instead of a small number of traditionally large generators, the power system resource mix is moving to one with a high percentage of a large number of small units. These can increase the number of similar or identical units, leading to chattering (switching back and forth among committed units between iterations). This research investigates alternative and scalable ways of increasing the high penetration of these resources.

First, …

Generalized Participation Factors On Nonlinear Power System Oscillations, Tianwei Xia

Doctoral Dissertations

This work investigates the linear and nonlinear participation factors in power system oscillations, introducing novel model-based and measurement-based approaches for stability analysis.

From the measurement perspective, this research proposes a method for estimating participation factors from generator response measurements under diverse disturbances. The devised technique computes extended participation factors that align precisely with model-based factors, given that the measured responses satisfy an ideally symmetric condition. The symmetric condition is further relaxed by identifying a coordinate transformation from the original measurement space to an optimally symmetric space, thereby achieving the ideal estimation of participation factors from measurements alone. The effectiveness of …

The Synthesis And Optimization Of Sulfide And Halide Solid Electrolytes For All Solid-State Batteries, Teerth Brahmbhatt

Doctoral Dissertations

Countries and organizations around the world have established ambitious targets to transition away from fossil fuel-based energy sources and devices. The transition is focused on cleaning up power generation by converting coal, natural gas, and oil-based power generation to renewables and nuclear energy. Decarbonizing other sectors of energy use, transportation for example, will require broader electrification. To drive this move away from fossil fuel powered transportation will require portable energy storage devices. Conventional lithium-ion batteries are a popular candidate to lead this shift. However, these batteries often rely on flammable liquid electrolytes and carbon anodes that suffer from low energy …

Deep Learning Based Power System Stability Assessment For Reduced Wecc System, Yinfeng Zhao

Doctoral Dissertations

Power system stability is the ability of power system, for a giving initial operating condition, to reach a new operation condition with most of the system variables bounded in normal range after subjecting to a short or long disturbance. Traditional power system stability mainly uses time-domain simulation which is very time consuming and only appropriate for offline assessment.

Nowadays, with increasing penetration of inverter based renewable, large-scale distributed energy storage integration and operation uncertainty brought by weather and electricity market, system dynamic and operating condition is more dramatic, and traditional power system stability assessment based on scheduling may not be …

Impact Of Renewables On Grid Strength, Transient Stability, And Grid Operation Characterization, Abigail E. Till

Doctoral Dissertations

Increasing amounts of inverter based resources (IBR) are being added to the grid. With environmental and climate change concerns, even more is projected to be added. Many companies and regions are setting goals for high levels of renewables.

As IBR are added to the grid, it changes how the power system responds to disturbances. With less traditional synchronous machines on the system, this decreases the inertia and can add stability concerns. Studies are required to know how power systems will respond to the change in generation resources. This dissertation contributes to studying transient stability and grid strength on the North …

Resiliency Of Power Systems In The Cyber Layer: Application To Load Forecasting And Security Assessment, Mojtaba Dezvarei

Doctoral Dissertations

Integrating sensors, actuators, and communication infrastructure in the electrical grid creates a smart grid, known as a cyber-physical system (CPS), which combines the physical framework with a cyber layer. The cyber layer is crucial as it houses the decision-making responsible for reliable operation. However, the complexity of the physical layers, due partly to the deployment of integrated battery resources (IBRs), and the cyber layer itself, introduces challenges such as reliance on measurement quality and vulnerability to data corruption from cyber threats. These challenges result in uncertainties in the CPS framework, emphasizing the need for accurate and robust responses from the …

Impacts Of High Renewable Power Grids On System Planning And Monitoring, Zhihao Jiang

Doctoral Dissertations

To achieve the goal of a carbon pollution-free electricity sector by 2035 proposed by Biden’s Administration, the U.S. power grids are expecting a dramatic transformation in the resource mix of electricity generation. This dissertation will present related research in several different aspects that will be largely affected by the clean energy transition.

The increasing size and complexity of the bulk power systems have made it more computationally burdensome to simulate the power system in full-size. As an alternative to traditional model-based methods, Chapter 2 proposes a measurement-based model reduction approach using system identification techniques. Chapter 3 presents a parameter fine-tuning …

Consensus-Based Active And Reactive Power Control And Management Of Microgrids, Shruti Singh

Electronic Theses and Dissertations

Microgrids incorporating distributed generation and renewable energy sources offer potential solutions to the energy crisis while modernizing traditional grids. Despite cost-effectiveness in some technologies, financial support remains crucial for expensive ones like PV, fuel cells, and storage technologies. Microgrids bring economic benefits, efficiency, reduced emissions, and improved power quality. Their success hinges on cost reductions in renewables, storage, reliability, and energy management systems, enabling operation both with and without the utility grid.

Economic Dispatch optimizes system costs, considering all constraints. Various methods tackle this problem, including quadratic convex functions, Lagrangian relaxation, and quadratic programming. For microgrids with distributed generators, seamless …

Digital Twins And Artificial Intelligence For Applications In Electric Power Distribution Systems, Deborah George

All Theses

As modern electric power distribution systems (MEPDS) continue to grow in complexity, largely due to the ever-increasing penetration of Distributed Energy Resources (DERs), particularly solar photovoltaics (PVs) at the distribution level, there is a need to facilitate advanced operational and management tasks in the system driven by this complexity, especially in systems with high renewable penetration dependent on complex weather phenomena.

Digital twins (DTs), or virtual replicas of the system and its assets, enhanced with AI paradigms can add enormous value to tasks performed by regulators, distribution system operators and energy market analysts, thereby providing cognition to the system. DTs …

Band Alignments Of Metal/Oxides-Water Interfaces Using Ab Initio Molecular Dynamics, Yong-Bin Zhuang, Jun Cheng

Journal of Electrochemistry

Band alignments of electrode-water interfaces are of crucial importance for understanding electrochemical interfaces. In the scenario of electrocatalysis, applied potentials are equivalent to the Fermi levels of metals in the electrochemical cells; in the scenario of photo(electro)catalysis, semiconducting oxides under illumination have chemical reactivities toward redox reactions if the redox potentials of the reactions straddle the conduction band minimums (CBMs) or valence band maximums (VBMs) of the oxides. Computational band alignments allow us to obtain the Fermi level of metals, as well as the CBM and VBM of semiconducting oxides with respect to reference electrodes. In this tutorial, we describe …

Recent Progress Of Bifunctional Electrocatalysts For Oxygen Electrodes In Unitized Regenerative Fuel Cells, Tian-Long Zheng, Ming-Yu Ou, Song Xu, Xin-Biao Mao, Shi-Yi Wang, Qing-Gang He

Journal of Electrochemistry

Unitized regenerative fuel cells (URFCs), which oxidize hydrogen to water to generate electrical power under thefuel cells (FCs) mode and electrolyze water to hydrogen under the water electrolysis (WE) mode for recycling, areknown as clean and sustainable energy conversion devices. In contrast to the hydrogen oxidation reaction (HOR) andhydrogen evolution reaction (HER) on the hydrogen electrode side, the sluggish kinetics of oxygen reduction reaction(ORR) and oxygen evolution reaction (OER) on the oxygen electrode side requires highly efficient bifunctional oxygencatalysts. Conventional precious metal oxygen catalysts combine Pt and IrO₂ with excellent ORR and OER activities toachieve bifunctional electrocatalysis performance, but …

Designing Intelligent Energy Efficient Scheduling Algorithm To Support Massive Iot Communication In Lora Networks, Jui Mhatre

Master of Science in Computer Science Theses

We are about to enter a new world with sixth sense ability – “Network as a sensor -6G”. The driving force behind digital sensing abilities is IoT. Due to their capacity to work in high frequency, 6G devices have voracious energy demand. Hence there is a growing need to work on green solutions to support the underlying 6G network by making it more energy efficient. Low cost, low energy, and long-range communication capability make LoRa the most adopted and promising network for IoT devices. Since LoRaWAN uses ALOHA for multi-access of channels, collision management is an important task. Moreover, in …