If anyone has a close look at the state of the NORTHERN HEMISPERE'S atmosphere and compare it to the southern one, it is a shock. Up to 2 km in height the air is thick with brown particles, so much so that is not possible to view farther than 30km on a clear summer's day in continental europe. This "brown-haze" is also visible in the Rocky Mountains, Caribbean Is. and other not likely industrialised places. It is a constant feature North America, too. Just have a look towards the horizon with the Sun in your back and imagine that the sky is actually blue near the horizon in the southern hemisphere. You can also see the n-hemi muck well in the sunset and sunrise. Usually it is most shocking at sunrise, when the air has settled and the band of pollution is extra dense above the ground.

Consider the fragility of our "breathable" atmosphere. If Earth was reduced to the size of a bowling ball, it would be thick as your fingerprint. You couldn't even feel Mount Everest!

From my observations while flying from New Zealand to Europe, this extreme pollution exists all around the globe between 40 and 70 deg northern latitude.

The winds circle the globe very rapidly and distribute the pollution widely. This we know since the chinese atmospheric atom-bomb test, where the radioactive particles took only 10 days to circle the globe. And the northern hemisphere is "filling up" because of the shear magnitude of the emissions.

The load of particles is so enormous that it must have an effect on the food-chain by itself. This is (or will be) a contributor to the slow contamination with dangerous substances of soil and water. An example is the air-borne fertilisation of the otherwise nutrient-poor dune-landscape in northern Germany. This effect will *in time* neccessarily overtake the chemical poisoning of soil and water.

BTW: 2,4 D is still in use in New Zealand. There has been massive use of DDT in New Zealand until quite recently. Only this year (1996) we have actually stopped selling leaded gasoline !!!

The vanadium battery, if made a high priority, would only need a short time of development by dedicated engineers/industry and it can eventually be massproduced.

Infrastructure ("vanadium-gas-stations") could be widely installed in as short a time as a year, if a country would see the cleaning up of the atmosphere as being of national interest and enact the legislation. Germany seems particularly well suited.

I would like this message to get through to auto-manufactures, public officials and enterprising people who can disseminate and implement such information. Read this material. If you are convinced (as I am) after examining the technical data that this vanadium battery should be commercially available in many forms e.g. for electric vehicles, energy-autonomous homes and industry, I think it might be a good idea to send this on to influential contacts that you may have, so that they can explore the possibilities of the vanadium battery.

So, here are the completly unsorted articles & abstracts which I have gathered on the subject, since I heard it on a Radio Australia science programme. There are 4 email-parts:

1 ENERGY FOCUS magazine article (this email you are reading now; 46k) 3 PHOTOVOLTAICS AND VANADIUM BATTERIES (59k) 4 STATUS OF THE VANADIUM BATTERY DEVELOPMENT (60k) 5 UNIKEN, ENERGY FOCUS (magazine), Swedish experiments (25k)

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(Adopted from a lecture by Maria Skyllas-Kazacos to the 1994 ERDC Annual General Meeting)

With increasing public awareness and concern over greenhouse gas emissions, ozone layer depletion and high levels of pollution in major cities around the world, the last decade has seen renewed interest in renewable and alternative energy technologies.

One of the critical obstacles in the implementation of renewable energy systems, has been the lack of a suitable energy storage system which will allow supply to better match energy demand.

SimiIarly, the recent strong push in USA for zero emission vehicles in an effort to decrease the intolerably high levels of pollution from motor cars, has led to a major effort around the world to develop suitable rechargeable batteries which will be able to slowly replace the internal combustion engine as power sources for vehicles.

Electrochemical systems such as secondary batteries and fuel cells convert the energy from electrochemical reactions directly into low voltage, direct current electricity.

They are ideally suited for energy storage as they offer the possibility of practical energy efficiency as high as 90%.

Batteries have a very wide range of energy storage applications. To date the only commercially available battery system that is feasible for any of these applications is the lead acid battery.

Unfortunately, this battery possesses a number of limitations for such energy storage applications and this has led to an ongoing effort around the world to solve the problem of energy storage using advanced battery systems.

One of the largest co-ordinated programmes to develop alternative energy and energy storage technologies was initiated in the early 1980s in Japan with the establishment of the New Energy Development Organisation (NEDO).

Japan's leading role in this area was prompted by the nation's almost total dependence on imported oil, which makes its energy supply structure extremely vulnerable.

As part of research and development, efforts in alternative energy technologies, NEDO initiated a large programme in energy conversion and storage. In addition to further improvements in lead acid technology, four new battery systems were selccted for initial evaluation at up to the 60 kW size. These systems were zinc chlorine, zinc bromine, sodium sulphur and iron chromium (Fe Cr) redox flow battery.

Following initial research and development efforts with all four systems, the zinc-bromine and sodium sulphur batteries were selected for the lMW demonstration phase, based on their superior performance and footprint energy density compared to the other two systems.

The Fe Cr battery system has shortcomings but in 1984 thc attractive features offercd by redox flow battery systems prompted The University of New South Wales (UNSW) to investigate using alternative redox couples to overcome some of the limitations.

To eliminate the inherent problem of cross contamination of the two electrolyte solutions, vanadium was selectcd as it exists in several oxidation states (0. 2, 3, 4, & 5) giving rise to a number of potentially useful redox couples.

The development of the vanadium redox battery at the UNSW,began in 1985 under a Commonwealth NERDC Grant.Since then, further research and development has been funded by the NSW Department of Minerals and Energy (now the Department of Energy), Mount Resources Ltd and recently by the Energy Research and Development Corporation (ERDC) and the Australian Research Council (ARC).

The vanadium battery is now at a relatively advanced stage of development with three 1 to 3 kW prototype batteries already constructed and tested.

Overall energy efficiency as high as 90% has been achieved to date, not including pumping energy losses.

Pumping losses have been estimatcd at 2 to 3% so that even at 87 to 88% overall energy efficiency, the vanadium battery is proving to be one of the most efficient energy storage systems currently under development.

To date two commercial licenses have been granted by Unisearch Ltd for the commercialisation of the vanadium redox battery in stationary energy storage applications.

Thai Gypsum Products in Thailand has been granted a Unisearch license to manufacture and use the vanadium redox battery in residential photovoltaic applications and in non grid interactive commercial peak shaving in South East Asia.

A consortium comprised of Mitsubishi Petrochemicals and Kashima Kita Power Corporation of Japan have also been licensed to further develop and commercialise the vanadium redox battery world wide, excluding South East Asia. China and Australia, in large scale load levelling systems and other stationary applications.

The consortium's plans are to construct and test a 300 kW vanadium battery system by 1996, and commission a 2 MW demonstration load levelling system in the Tokyo area by 1999.

In December1992, a 1kW/12 kWh vanadium battery was installed in a Solar Demonstration House in Thailand by the UNSW Vanadium Battery Development Group in collaboration with the UNSW Centre for Photovoltaic (PV) Devices and Systems and Thai Gypsum Products Co Ltd.

The PV/battery system is a precommercial prototype version of a grid interactive system that the battery licensee,Thai Gypsum, is intending to install in residential developments in Thailand and other Asian countries.

The first demonstration system was designcd to operate with alternating current loads and power a small air conditioner of less than 8OO watts. A National CU-700 K split system compressor type air conditioner was chosen as the load. The 1 kW/12 kWh battery included a 12 cell stack, giving a system voltage of 16.8 volts. Each of the two reservoirs contains 200 litres of electrolyte.

A roof mounted array of 36 Kyocera LA441K63 photovoltaic modules provided 2.2 kW of installed PV.

Butler Solar Products, Australia, designers of the Siemens range of SUNSINE inverters, modified an existing 1 kW, 12 V stand alone SUNSINE inverter for the 16.8 volt PV/vanadium battery system.

A 36 cell stack has subsequently been constructed at UNSW and sent to Thailand to replace the 12 cell stack in the solar house.

A 4 kVA Geebung grid interactive inverter is currently being tested with the vanadium battery which is operating with a microprocessor controller built by the UNSW Centre for Photovoltaic Systems and Devices.

The controller was designed to optimise the efficiency of the battery in this application.

In addition to the field testing, Thai Gypsum is currently undertaking manufacturing trials of the battery components.

Some further development is now required to optimise the conducting plastic electrode fabrication so as to achieve the target resistivity of 2 ohm per 2 square centimetre for a cell.

It is expected that by mid 1995, Thai Gypsum will have completed the first production prototype stacks for more extensive field trials.

The vanadium redox battery is continuing to show great promise as an efficient, low cost energy storage system for stationary applications.

A refuellable battery such as the vanadium redox system would also be the ideal approach for electric vehicles since it could offer an instant recharge by exchanging electrolytes at special refuelling stations.

The redox cell battery is the only type of battery system available that offers the possibility of instant recharge while still permitting conventional electrical recharge to be employed.

This means the vanadium redox battery electrolyte could be treated as an alternative liquid fuel but one that can be regenerated indefinitely.

This feature is of enormous significance in electric vehicle applications where public acceptance will be more readily achieved if behaviour patterns do not need to be radically modified.

There has been considerable interest in the area of electric vehiclcs for many years but until fairly recently this has mainly come from a small group of enthusiasts.

The introduction of the stringent California exhaust emission standards, which, from 1998 will require major manufacturers to ensure 2% of their sales are of zero emission vebicles, has turned the situation around.

Car manufacturers around the world are now embarking on major programmes to develop electric vehicles.

The three major US car manufacturers - General Motors, Ford and Chrysler - have formed the Advanced Battery Consortium to identify and develop advanced batteries that are able to meet strict performance and range requirements.

The aim is to provide an electric vehicle alternative that will be fully traffic compatible.

The General Motors Impact, a high performance electric sports car, demonstrates electric cars has moved beyond the golf buggy era.

Other companies such as BMW, Mercedes, Hyundai, Mazda, Mitsubishi and Peugeot haye also embarked on major electric vehicle programmes utilising various battery technologies. Mercedes has been investigating sodium nickel chloride batteries, Peugeot nickel cadmium batteries and Hyundai nickel hydride batteries.

At present the vanadium battery system is suited to stationary or niche mobile applications due to its low energy density of 20 to 25 Wh/kg and resultant large size in high capacity units.

Research currently underway at the UNSW is showing that an energy density of 80 to100 Wh/ kg could be achieved within the next five years.

In an effort to demonstrate the concept of the vanadium redox battery for electric vehicles,a seed grant was obtained from Pacific Power to construct a battery and install it in an electric golf buggy.

A commercially available gulf buggy powered by lead acid batteries was loaned by the US manufacturer E-Z-Go through its Australian distributor, which is Deep Down Distribution P/L. The golf buggy was originally powered by six, 6 volt lead acid batteries located under the seat.

Calculations showed that the size of battery required to power the vehicle was a 30 cell stack with an electric area of 500 square centimetres. Budget limitations procluded the fabrication of separate flow frame and electrode moulds for such a battery stack so it was necessary to use the larger, 1,500 square centimetre moulds manufactured for the solar house battery project in Thailand. This resulted in a battery approximately 50% longer and roughly three times the cross sectional area that would have been required with specifically designed moulds.

The oversized battery was mounted on the back of the golf buggy with the two tanks containing the vanadium electrolytes positioned under the seat.

Preliminary road trials have been undertaken and the vanadium battery powered golf buggy was found to perform exceptionally well.

It carried two passengers with ease despite a total vehicle weight including the two passengers in excess of 400 kg.

Because of its relatively low energy density, the vanadium battery would presently be limited to larger vehicles such as trucks, buses and vans.

The energy density is related to the amount of vanadium, as sulphate. dissolved in solution and is tied to the solubility of the vanadium salts in sulphuric acid, approximately 2 Moles/litre.

Early studies with modified electrolytes are showing great promise and solutions of over 4 moles per litre of vanadium have already ben prepared in the laboratory.

Combining these concentrated electrolytes with an oxygen regeneration system for the positive electrolyte could give energy densities of 80 to lO0 Wh/kg within the next five years.

This would lead to a battery which would meet all the requirements stipulated by car manufacturers when assessing the current and future battery technologies for electric vehicles.

Whether it is the vanadium battery or some other technology, the time will certainly come when quiet, pollution free vehicles will be driven around our cities and we can look forward to the day when we can all breathe clean air once again.

The vanadium redox flow battery was developed by Professor Maria Skyllas-Kazacos and her team at the University of New South Wales. It is a low Cost, low environmental impact battery that has a superior deep cycling life and can be mechanically refuelled in minutes.

Today's lead acid batteries, commonly used to start cars store energy in solid electrodes while the vanadium redox battery stores energy in a liquid electrolyte solution of vanadium pentoxide dissolved in sulphuric acid.

The electrolyte can be charged or discharged by pumping it through the battery stack and either supplying electric power to the stack or taking power from the stack. It can also be recharged by having the spent electrolyte pumped out and a fresh charge of electrolyte pumped in.

The spent electrolyte can then be recharged in another battery with elcctricity from the mains or from renewable energy eources.

This raises the opportunity for the establishment of refuelling stations so that electric vehicles could exchange their electrolyte and then continue on their way with no more delay than if refuelling with petrol or diesel.

Development of the vanadium redox flow battery has been assisted by funding from the State Energy Research and Development Fund, SERDF, which is administered by the NSW Department of Energy.

SERDF is currently funding 54 energy research and development projects that are important to NSW with a total SERDF contribution of $7,500,000.

For further information on SERDF, please phone Dr David Hemming, NSW Department of Energy +61 2 99018836.

Vanadium redox flow battery technology is protected under a number of patents and further patent applications are in progress.

Licences have been granted to Mitsubishi Chemicals Corp, Kashima Power Corp and Thai Gypsum Products Public Co for stationary applications. Very large batteries in the Megawatt hour range are expected to be in commercial production by 1998.

Licences are available for some stationary applications in some of the largest countries of Asia and for vehicular applications throughout the world.

There are currently no licences issued for the use of the technology in China.

With mandated zero emission targets for urban traffic in parts of USA and other initiatives in Europe, the world market for electric vehicle batteries is expected to exceed $US5 billion by 2004.