New Page 1

LA GRAMMATICA DI ENGLISH GRATIS IN VERSIONE MOBILE   INFORMATIVA PRIVACY

  NUOVA SEZIONE ELINGUE

 

Selettore risorse   

   

 

                                         IL Metodo  |  Grammatica  |  RISPOSTE GRAMMATICALI  |  Multiblog  |  INSEGNARE AGLI ADULTI  |  INSEGNARE AI BAMBINI  |  AudioBooks  |  RISORSE SFiziosE  |  Articoli  |  Tips  | testi pAralleli  |  VIDEO SOTTOTITOLATI
                                                                                         ESERCIZI :   Serie 1 - 2 - 3  - 4 - 5  SERVIZI:   Pronunciatore di inglese - Dizionario - Convertitore IPA/UK - IPA/US - Convertitore di valute in lire ed euro                                              

 

 

WIKIBOOKS
DISPONIBILI
?????????

ART
- Great Painters
BUSINESS&LAW
- Accounting
- Fundamentals of Law
- Marketing
- Shorthand
CARS
- Concept Cars
GAMES&SPORT
- Videogames
- The World of Sports

COMPUTER TECHNOLOGY
- Blogs
- Free Software
- Google
- My Computer

- PHP Language and Applications
- Wikipedia
- Windows Vista

EDUCATION
- Education
LITERATURE
- Masterpieces of English Literature
LINGUISTICS
- American English

- English Dictionaries
- The English Language

MEDICINE
- Medical Emergencies
- The Theory of Memory
MUSIC&DANCE
- The Beatles
- Dances
- Microphones
- Musical Notation
- Music Instruments
SCIENCE
- Batteries
- Nanotechnology
LIFESTYLE
- Cosmetics
- Diets
- Vegetarianism and Veganism
TRADITIONS
- Christmas Traditions
NATURE
- Animals

- Fruits And Vegetables



ARTICLES IN THE BOOK

  1. AAAA battery
  2. AAA battery
  3. AA battery
  4. A battery
  5. Absorbent glass mat
  6. Alessandro Volta
  7. Alkaline battery
  8. Alkaline fuel cell
  9. Aluminium battery
  10. Ampere
  11. Atomic battery
  12. Backup battery
  13. Baghdad Battery
  14. Batteries
  15. Battery charger
  16. B battery
  17. Bernard S. Baker
  18. Beta-alumina solid electrolyte
  19. Betavoltaics
  20. Bio-nano generator
  21. Blue energy
  22. Bunsen cell
  23. Car battery
  24. C battery
  25. Clark cell
  26. Concentration cell
  27. Coulomb
  28. 2CR5
  29. Daniell cell
  30. Direct borohydride fuel cell
  31. Direct-ethanol fuel cell
  32. Direct methanol fuel cell
  33. Dry cell
  34. Dry pile
  35. Duracell
  36. Duracell Bunny
  37. Earth battery
  38. Electric charge
  39. Electric current
  40. Electricity
  41. Electrochemical cell
  42. Electrochemical potential
  43. Electro-galvanic fuel cell
  44. Electrolysis
  45. Electrolyte
  46. Electrolytic cell
  47. Electromagnetism
  48. Electromotive force
  49. Energizer Bunny
  50. Energy
  51. Energy density
  52. Energy storage
  53. Flashlight
  54. Float charging
  55. Flow Battery
  56. Formic acid fuel cell
  57. Fuel cell
  58. Fuel cell bus trial
  59. Galvanic cell
  60. Gel battery
  61. Grove cell
  62. Half cell
  63. History of the battery
  64. Hybrid vehicle
  65. Lead-acid battery
  66. Leclanché cell
  67. Lemon battery
  68. List of battery sizes
  69. List of battery types
  70. List of fuel cell vehicles
  71. Lithium battery
  72. Lithium ion batteries
  73. Lithium iron phosphate battery
  74. Lithium polymer cell
  75. LR44 battery
  76. Luigi Galvani
  77. Manganese dioxide
  78. Memory effect
  79. Mercury battery
  80. Metal hydride fuel cell
  81. Methane reformer
  82. Methanol reformer
  83. Michael Faraday
  84. Microbial fuel cell
  85. Molten carbonate fuel cell
  86. Molten salt battery
  87. Nickel-cadmium battery
  88. Nickel-iron battery
  89. Nickel metal hydride
  90. Nickel-zinc battery
  91. Open-circuit voltage
  92. Optoelectric nuclear battery
  93. Organic radical battery
  94. Oxyride battery
  95. Panasonic EV Energy Co
  96. Peukert's law
  97. Phosphoric acid fuel cell
  98. Photoelectrochemical cell
  99. Polymer-based battery
  100. Power density
  101. Power management
  102. Power outage
  103. PP3 battery
  104. Primary cell
  105. Prius
  106. Proton exchange membrane
  107. Proton exchange membrane fuel cell
  108. Protonic ceramic fuel cell
  109. Radioisotope piezoelectric generator
  110. Ragone chart
  111. RCR-V3
  112. Rechargeable alkaline battery
  113. Reverse charging
  114. Reversible fuel cell
  115. Searchlight
  116. Secondary cell
  117. Short circuit
  118. Silver-oxide battery
  119. Smart Battery Data
  120. Smart battery system
  121. Sodium-sulfur battery
  122. Solid oxide fuel cell
  123. Super iron battery
  124. Thermionic converter
  125. Trickle charging
  126. Vanadium redox battery
  127. Volt
  128. Voltage
  129. Voltaic pile
  130. Watch battery
  131. Water-activated battery
  132. Weston cell
  133. Wet cell
  134. Zinc-air battery
  135. Zinc-bromine flow battery
  136. Zinc-carbon battery

 

 
CONDIZIONI DI USO DI QUESTO SITO
L'utente può utilizzare il nostro sito solo se comprende e accetta quanto segue:

  • Le risorse linguistiche gratuite presentate in questo sito si possono utilizzare esclusivamente per uso personale e non commerciale con tassativa esclusione di ogni condivisione comunque effettuata. Tutti i diritti sono riservati. La riproduzione anche parziale è vietata senza autorizzazione scritta.
  • Il nome del sito EnglishGratis è esclusivamente un marchio e un nome di dominio internet che fa riferimento alla disponibilità sul sito di un numero molto elevato di risorse gratuite e non implica dunque alcuna promessa di gratuità relativamente a prodotti e servizi nostri o di terze parti pubblicizzati a mezzo banner e link, o contrassegnati chiaramente come prodotti a pagamento (anche ma non solo con la menzione "Annuncio pubblicitario"), o comunque menzionati nelle pagine del sito ma non disponibili sulle pagine pubbliche, non protette da password, del sito stesso.
  • La pubblicità di terze parti è in questo momento affidata al servizio Google AdSense che sceglie secondo automatismi di carattere algoritmico gli annunci di terze parti che compariranno sul nostro sito e sui quali non abbiamo alcun modo di influire. Non siamo quindi responsabili del contenuto di questi annunci e delle eventuali affermazioni o promesse che in essi vengono fatte!
  • L'utente, inoltre, accetta di tenerci indenni da qualsiasi tipo di responsabilità per l'uso - ed eventuali conseguenze di esso - degli esercizi e delle informazioni linguistiche e grammaticali contenute sul siti. Le risposte grammaticali sono infatti improntate ad un criterio di praticità e pragmaticità più che ad una completezza ed esaustività che finirebbe per frastornare, per l'eccesso di informazione fornita, il nostro utente. La segnalazione di eventuali errori è gradita e darà luogo ad una immediata rettifica.

     

    ENGLISHGRATIS.COM è un sito personale di
    Roberto Casiraghi e Crystal Jones
    email: robertocasiraghi at iol punto it

    Roberto Casiraghi           
    INFORMATIVA SULLA PRIVACY              Crystal Jones


    Siti amici:  Lonweb Daisy Stories English4Life Scuolitalia
    Sito segnalato da INGLESE.IT

 
 



BATTERIES
This article is from:
http://en.wikipedia.org/wiki/Vanadium_redox_battery

All text is available under the terms of the GNU Free Documentation License: http://en.wikipedia.org/wiki/Wikipedia:Text_of_the_GNU_Free_Documentation_License 

Vanadium redox battery

From Wikipedia, the free encyclopedia

 

The vanadium redox (and redox flow) battery in its present form (with sulphuric acid electrolytes) was patented by the University of New South Wales in Australia in 1986 [1]. It is a type of rechargeable flow battery that employs vanadium redox couples in both half-cells, thereby eliminating the problem of cross contamination by diffusion of ions across the membrane. Although the use of vanadium redox couples had been suggested much earlier [2], and all-vanadium redox flow batteries by NASA researchers and by Albero Pellegri and Placido Spaziante in 1978 [3], the first successful demonstration and commercial development was by Maria Skyllas-Kazacos and co-workers at the University of New South Wales in the 1980's [4]. The Vanadium redox battery exploits the ability of vanadium to exist in 4 different oxidation states, and uses this property to make a battery that has just one electroactive element instead of two.

The main advantages of the vanadium redox battery is that it can offer almost unlimited capacity simply by using larger and larger storage tanks, it can be left completely discharged for long periods with no ill effects, it can be recharged simply by replacing the electrolyte if no power source is available to charge it, and if the electrolytes are accidentally mixed the battery suffers no permanent damage.

The main disadvantages with vanadium redox technology are a relatively poor energy-to-volume ratio, and the system complexity in comparison with standard storage batteries.

Diagram of a Vanadium Flow Battery
Diagram of a Vanadium Flow Battery

Operation

A Vanadium redox battery consists of an assembly of power cells in which the two electrolytes are kept separated by an ion exchange membrane. As stated above both electrolytes are vanadium based. The electrolyte in the positive half-cells contains VO2+ and VO2+ ions, the electrolyte in the negative half-cells, V3+ and V2+ ions. The electrolytes are typically prepared by a number of processes, including electrolytically dissolving vanadium pentoxide (V2O5) in sulphuric acid (H2SO4). The solution remains strongly acidic in use.

In vanadium flow batteries, both half-cells are additionally connected to storage tanks and pumps so that very large volumes of the electrolytes can be circulated through the cell. This circulation of liquid electrolytes is somewhat cumbersome and does restrict the use of vanadium flow batteries in mobile applications, effectively confining them to large fixed installations, although there is one company focusing on electric vehicle applications, where rapid replacement of electrolyte is used to refuel the battery.

When the vanadium battery is charged, the VO2+ ions in the positive half-cell are converted to VO2+ ions when electrons are removed from the positive terminal of the battery. Similarly in the negative half-cell, electrons are introduced converting the V3+ ions into V2+. During discharge this process is reversed and results in a typical open-circuit voltage of 1.41 V at 25 °C.

Other useful properties of Vanadium flow batteries are their very fast response to changing loads and their extremely large overload capacities. Studies by the University of New South Wales have shown that they can achieve a response time of under half a millisecond for a 100% load change, and allowed overloads of as much as 400% for 10 seconds. The response time is mostly limited by the electrical equipment.

Generation 2 Vandium redox batteries will approximately double the energy density and increase the temperature range in which the battery can operate.

Applications

The extremely large capacities possible from vanadium redox batteries make them well suited to use in large power storage applications such as helping to average out the production of highly variable generation sources such as wind or solar power, or to help generators cope with large surges in demand.

Their extremely rapid response times also make them superbly well suited to UPS type applications, where they can be used to replace Lead-acid batteries and even diesel generators.

Installations

Currently installed vanadium batteries include:

  • A 1.5MW UPS system in a semiconductor fabrication plant in Japan
  • A 275 kW output balancer in use on a wind power project in the Tomari Wind Hills of Hokkaido
  • A 200 kW, 800kWh output leveler in use at the Huxley Hill Wind Farm on King Island, Tasmania
  • A 250 kW, 2MWh load leveler in use at Castle Valley, Utah
  • A 12 MWh flow battery is also to be installed at the Sorne Hill wind farm, Ireland [5].

See also

 
  • Battery (electricity)
  • Flow Battery
  • Lead-acid battery
  • Electrochemical cell
  • Fuel cell
  • Energy storage

References

  1.   M. Skyllas-Kazacos, M. Rychcik and R. Robins, in AU Patent 575247 (1986), to Unisearch Ltd.
  2.   P. A. Pissoort, in FR Patent 754065 (1933)
  3.   A. Pelligri and P. M. Spaziante, in GB Patent 2030349 (1978), to Oronzio de Nori Impianti Elettrochimici S.p.A.
  4.   M. Rychcik and M. Skyllas-Kazacos, J. Power Sources, 22 (1988) 59-67

Additional references

  • Presentation paper from the IEEE summer 2001 conference
  • UNSW Site on Vanadium batteries
  • Report by World Energy

External links

  • VRB at UNSW
  • VRB at everything2
Retrieved from "http://en.wikipedia.org/wiki/Vanadium_redox_battery"