An Overview of Future Energy Storage Vanadium Redox Flow Battery (VRFB)

This thesis has been submitted to the Department of Electrical and Electronic Engineering in partial fulfillment of the requirement for the degree of Bachelor of. This dissertation report entitled “An Overview of Future Energy Storage Vanadium Redox Flow Battery (VRFB)” submitted by Obaidul Haque, ID. This thesis is submitted to Daffodil International University for partial fulfillment of the requirement of the degree of B.Sc.

Daffodil International University 5 My intellectual debt is to the Department of Electrical Engineering, Daffodil International University, Bangladesh, for giving me the space to carry out this project, which is an indispensable fragment of the B.Sc. I am also thankful to the faculties of Department of Electrical Engineering for providing their valuable guidance and time during the course of this project. Daffodil International University 6 Energy conservation analysis is the backbone of energy system analysis and design.

The Vanadium Redox Flow Battery (VRFB) is one of the most promising electrochemical energy storage systems considered suitable for a fair range of renewable energy applications, which stores electrical energy by changing the oxidation numbers of anolyte and catholyte through redox reaction. The significance of this study is to find out a possible comparison between the available energy storage system nowadays and to adopt the most feasible and efficient energy storage system. From the observation and research, it was highlighted that vanadium redox flow battery can be the long lasting &.

In addition, there are few limitations and findings of recent researchers who noted that the adoption of VRFB for any particular application is not feasible that have been reviewed.

Introduction

Methodology

ENERGY STORAGE

Brief Review of Energy Storage System
Technological Overview
Battery Energy Storage
Positive Electrode
Negative Electrode
Summery of Advantage & Disadvantage

In these views, BESS provides an advantageous disconnect between resource availability and renewable energy utilization. Instances of the final frameworks that reject hydrogen or methane storage useful for long-distance administrations are the redox-flow batteries, which have the preferred position where energy and power are freely versatile (the energy limit depends on the tank, while the cell stack determines the current). [8]. Vanadium redox-flow batteries are economically available in various isolated versatile sizes, but the still significant expense of the electrolyte arrangement and maintenance discourages their huge adoption[9].

ESS administrations can be: slave administration (ie, repeat control, voltage guidance, roll and attitude hold, dark start assist, and so on), top shaving, load leveling, support in island or other assistance identified for the most part with private employment of ESS (eg, private use for extended self-use of DG generation, modern applications, uninterruptible power supply and so on) Orders of different can be applied to ESS[10]. The main applications that can be conveniently exploited by smart distribution grids fall into mid-term or at least short-term services. Electrochemical energy can be specified in different types which are Nickel Cadmium, Lithium Ion, Lead Acid, Fuel Cell and Redox Flow Battery (RFB).

They can be connected in parallel and provide power to homes as a standby during power outages. During a battery's life cycle, an interrupted or incomplete charging process can cause sulfuric acid to penetrate the water-acid mixture and accumulate at the bottom of the battery.[14] Due to the lack of acid at the top of the battery, i.e. fully charging solves this problem, completely mixing the electrolyte and leaving an even distribution of chemicals in the battery.

Lithium-ion batteries are much lighter than lead-acid batteries, can provide the same amount of voltage, and can be replaced in electric vehicles without major modifications. The energy density of this battery can be up to five times that of a lead-acid battery. During the discharge cycle, the electrode allows the flow of positive sodium ions, while at the same time electrons flow through the circuit of the device.

The severe environmental toxicity caused by the disposal of cadmium has led to the rapid development of the Ni/MH device[7]. Metal Hydride component negative electrodes are the main driver behind some of the advantages over lead acid and Ni/Cd systems. Daffodil International University 12 Figure 2.4: For the charging and discharging process of nickel metal hydride battery[5].

Most of the research is done to propose the design and modeling of metal hydride materials for electrodes. It has a limitation that it is mandatory to be stored in a charged state once the electrolyte is introduced to prevent degradation of the active chemicals.

Figure 2.1: Construction of Lead Acid Battery[13]

FLOW BATTERY TECHNOLOGY

Technical Review of VRFB
The Nernst Equation
Complete Cell System characteristics of VRFB
Technical Properties of VRFB
Recent Developments
Commercial Products
Design Cell & Stack
Design Development of Cell Components
Summery of Flow Battery
Discussion & Conclusion
Recommendation

This material is considered suitable for maintaining the required chemical stability and kinetics for optimal operation of an all-vanadium redox flow cell. Ion exchange membranes are identified as the most critical part of a redox flow battery. The chemical reaction of a vanadium bromide redox flow battery is given in the equation below.

The power or performance and capacity of the redox flow battery is determined by the stack size of the number of cells and the volume of the active material (electrolyte). Some of the major challenges to overcome in the performance of vanadium batteries are thermal stability related to the membrane, precipitation of vanadium and viscosity[20]. A modification of the Dioramic Company manufactured microporous separator; Dioramic Membrane was used in Vanadium Redox batteries due to their high stability.

The water content of the membrane is measured by taking the percent weight change before and after vacuum drying. The energy density of a redox flow battery is proportional to the concentration of the redox ions in solution, to the cell potential and to the number of electrons transferred during discharge per mole of active redox ions. The changes in the concentration of the electrochemical species affect the thermodynamic conditions and this will lead to the equilibrium differing in potentials due to the Nernst equation.

Based on analysis, increasing the current density could be one of the factors that could improve. Lead Acid (LA), Lithium Ion (Li-ion), Nickel Cadmium (Ni-Cd), Fuel Cell (FC) and Redox Flow Battery (RFB) are some of the energy storage systems previously mentioned under the electrochemical category. So far, V-RFB is one of the most promising technologies and can be satisfactorily used for a wide range of renewable energy applications due to its safety, long lifespan and scalability ability.

Recent research has focused more on the characteristics of V-RFB, but there is limited research on the characterization of the cell stack of V-RFB. The performance characterization of V-RFB is analyzed based on the charge and discharge condition of the battery. From the core theory of vanadium redox flow battery, the performance of the battery can be affected by the efficiency of the V-RFB.

The better the battery performance, the higher the V-RFB efficiency can be achieved. In contrast to conventional energy storage technologies, the VFB can independently scale the power and energy components of the system by storing redox active species outside the battery container itself[6].

Table 3.2: Detailed specification for VRB stack[22]

This is an opportunity for public and private sector banks, government departments to set up programs to encourage businesses, residences and industries to adopt flow batteries to not only solve the electricity situation in the short term but also manage electricity demand in the long term by in introducing renewable energy systems. Gandomi et al., "Critical Review - Experimental Diagnostics and Material Characterization Techniques Applied to Redox Flow Batteries," J. Park, "Effect of Nanofluidic Electrolyte on Electrochemically Enhanced Long-Term Performance of Vanadium Redox Flow Battery," Energy Storage, vol. .

Zhang, "Flow field design and optimization based on mass transport polarization control in a flow-through type vanadium flow battery," J. Zhao, "A high power density and long cycle life vanadium redox flow battery," Energy Storage Mater., vol. Al-yasiri, "Numerical and experimental investigation of new designs of all-vanadium redox flow batteries for performance improvement," 2017.

Yusoff, “Method approaches to prevent leakage cell stack of vanadium redox flow battery (VRFB),” IET Conf. Kale, “Dual Degree Stage-1 Report Modeling and Simulation of Vanadium Redox Flow Batteries Submitted by,” no.