摘 要

使用能量存储设备有一个有趣的增长， 因为不间断电源已经结合了电池技术，以便在电源故障时能够平稳的接通电源。 一个新的电池，钒氧化还原电池（VRB）由Maria Skyllas-Kazacos 及其同事于1984 年在悉尼新南威尔士大学提出。 VRB是使用钒离子的可充电电池，并提供许多独特的超常规电池。 VRB是紧急备用系统，已经在22-28V工作范围内进行了测试。其系统的能源效率优于80% ， 并且具有96.4%的电压效率和92.2%的电压效率。VRB的储能能力取决于电解质的体积和溶解在其中的离子的体积。

VRB将其能量存储在液体电解质中，其中重新放置在电池中。 使用VRB比常规电池系统的主要优点是通过增加储罐中的点解夜储存容量可以增加储能能力。 电池系统通过仿真／实验数据批准。

关键词：钒氧化还原电池（VRB），电动钒电池型号

Abstract

There is an interesting growing in the use of energy storage devices since Uninterruptable power sources have incorporated battery technology to allow smooth power to switch on in case of power failure. A new battery, the Vanadium Redox Flow Battery (VRB) was proposed by Maria Skyllas-Kazacos and co-workers in 1984 at University of New South Wales, in Sydney. VRB is rechargeable battery that use vanadium ion and provides many unique over conventional batteries. The VRB is an emergency back-up system which has been tested for operation between 22 – 28V operating range. Its system carried energy efficiencies superior to 80% and columbic as 96.4% and 92.2% voltage efficiencies. The energy storage capacity of the VRB relies on the volume of electrolyte and the volume of ions dissolved in it.

The VRB stores its energy in liquid electrolytes form where are redisposed in the battery. The main advantage of using VRB over conventional battery systems is that the energy storage capacity can be increase by increasing the volume of electrolyte storage in tanks. The battery system has been approved by simulation/experiment data.

Key Words: Vanadium Redox Flow Battery (VRB), electrical Vanadium battery Model

Table of contents

Acknowledgments I

摘 要 I

Abstract II

Chapter 1 Introduction 1

1.1Energy Storage System 1

1.2VRB Model 4

1.3Battery model 5

1.3.1Battery performance 5

1.4Motivation and purpose of this thesis 5

1.5Thesis outline 6

Chapter 2 Literature Review 7

2.1. Introduction of Vanadium Redox Battery 7

2.2. Basic principles and features of Vanadium Redox Flow Battery 8

Benefits of Vanadium Redox Battery for Large Scale Energy Storage. 9

2.3. Advantages of Vanadium Redox Flow Battery 10

2.4. Review of the electrical modeling 15

2.5. Review of thermal model 17

2.6. Review of state of charge methods 19

Chapter 3 Thermal hydraulic effects and efficiency of all Vanadium Redox Flow 23

3.1Introduction 23

3.2Pressure drop investigation and pump power 24

3.2.1. Pressure drop in hydraulic circuits 24

3.2.2. Pressure drop in stack 24

3.3. Model development and assumptions 26

3.3.1. Pump power investigation 26

3.3.2. Electrolytes flow rate 26

3.4. Battery performances and efficiencies 28

3.5. Simulation Results 29

3.5.1 Model validation and analysis 29

3.5.2. Stack temperature investigation 30

3.5.3. Stack, pipe and tank temperature effects 31

3.5.4. Battery electrical characteristics under various flow rates and temperatures 32

3.6. Conclusion 33

Chapter 4 Simulation amp; Results 34

4.1. Introduction 34

4.2. Thermal dependent electrical development 35

4.3. Model validation and simulation results 36

4.3.1. Temperature validation 37

4.3.2. Flow rate effect validation 38

4.3.3. Thermal dependent electrical model validation 39

Chapter 5 Conclusion 40

References 41

Summary

Battery energy storage technology is contemplated to be reliable, secure and mostly viable. Especially the redox flow battery that is a wise choice for large scale energy storage has mostly been researched by numerous industries or organizations around the world. In the flow batteries family, the most promising, Vanadium Redox Flow Battery a very competitive battery for large capacity energy storage in power grids caused by its minimal maintenance cost, a flexible design capacity, no cross contamination problem, long life time…

This paper introduces the Vanadium Redox Flow Battery, operation characteristics of VRB are analyzed. Electrical model and thermal hydraulic model are build up. The impact of electrolyte flow rates and the temperature on the battery performance, on the electrical characteristics and efficiencies are analyzed.

The temperature has an impressive impact on the battery efficiency, material lifetime and electrolytes stability. The pump effect is analyzed to evaluate the VRB temperature responses under various operating conditions. The numeric simulation is direct with a one kilowatt VRB system. The thermal hydraulic model is benchmarked with experimental information. The prototype analyzed can be used to develop the battery control strategy to achieve adequate thermal-hydraulic performance and energy efficiency.

Chapter 1 Introduction

The progress of safe energy storage sector has been a big problem for many years. The use of reliable and safe batteries in energy storage systems for emergency back-up would be beneficiary in the progress in the field as information, finance and telecommunication.

The incorporation of the Uninterruptable Power System (UPS) in the battery technology were universally used in financial, communication and informatics industries. UPS has been very reliable as it provided secure power for electrical materials and computer installations. In case of power failure, the UPS depended on the lead-acid batteries which provides less than 15 minutes of power supply time for a diesel generator to start running.

This process were having many issues such as flat starter battery, noise.

Vanadium Redox Flow Battery (VRB) is one the most suited energy storage system for large scale energy storage where renewable energy devices such solar and wind energies storage are stored in different tanks.

1.1Energy Storage System

Many renewable Energy devices are incorporated into the power grid to augment the environmental interest. Due to the penetration of large amount of stochastic power, the energy storage is well known to be the solution to improve the stability and reliability of distributed grid.

The Energy Storage System (ESS) has many characteristics:

• Provides uninterruptible power supply (UPS)
• Provides power fluctuation
• Discuss power quality problems [1] amp; [2].

The benefits of power grid for large energy storage involve peak shaving and load level. [3]