PDF Publication Title:
Text from PDF Page: 016
2.2 Types of Redox Flow Batteries RFB’s can be divided into two categories6: 1) True redox flow batteries, where all of the chemical species active in storing energy are fully dissolved in solution at all times. Examples of true RFB’s include the vanadium-vanadium and iron-chromium systems. True RFB’s achieve the complete separation of power and energy, along with the full advantages. 2) Hybrid redox flow batteries, where at least one of the chemical species is plated as a solid in the electrochemical cells during charge. Examples of hybrid RFB’s include the zinc-bromine and zinc-chlorine systems. In hybrid RFB’s, complete separation of power and energy is not achieved, because energy is stored in the metal which is plated in the electrochemical stack during charge. Other examples of hybrid batteries are metal-air batteries7 or semi-solid redox flow batteries8 Larger energy storage capacity requires a larger stack, so the distinction of the hybrid RFB from integrated cell architectures is only partly achieved. 2.3 Advantages and disadvantages The separation of power and energy is a key distinction of RFB’s, compared to other electrochemical storage systems. As described above, the system energy is stored in the volume of electrolyte, which can easily and economically be in the range of kilowatt-hours to 10’s of megawatt-hours, depending on the size of the storage tanks. The power capability of the system is determined by the size of the stack of electrochemical cells, which is the electrodes total area. The amount of electrolyte flowing in the electrochemical stack at any moment is rarely more than a fraction of the total amount of electrolyte in the tanks (for energy ratings corresponding to discharge at rated power for two to eight hours). Flow can easily be stopped during a fault condition. As a result, system vulnerability to uncontrolled energy release in the case of RFB’s is limited by system architecture just to a small percentage of the total energy stored. This feature is in contrast with packaged, integrated cell storage architectures (lead-acid, NAS, Li Ion), where the full energy of the system is connected at all times and available for discharge. It makes them more vulnerable to a system failure. Redox flow batteries have one main architectural disadvantage compared with integrated cell architectures of electrochemical storage. RFB’s tend to have lower volumetric energy densities (15-25 WhL-1) than integrated cell architectures (250– 693 WhL-1 for Li-ion), especially in the high power, short duration applications. This is due to the volume of electrolyte flow delivery and control components of the system, which is not used to store energy. In spite of this, RFB’s are available with system footprint below the EPRI substation target of <500 ft2 / MWh. 15PDF Image | Redox Flow Batteries Vanadium to Earth Quinones
PDF Search Title:
Redox Flow Batteries Vanadium to Earth QuinonesOriginal File Name Searched:
FJVG_TESIS.pdfDIY PDF Search: Google It | Yahoo | Bing
Salgenx Redox Flow Battery Technology: Salt water flow battery technology with low cost and great energy density that can be used for power storage and thermal storage. Let us de-risk your production using our license. Our aqueous flow battery is less cost than Tesla Megapack and available faster. Redox flow battery. No membrane needed like with Vanadium, or Bromine. Salgenx flow battery
CONTACT TEL: 608-238-6001 Email: greg@salgenx.com (Standard Web Page)