Vanadium Batteries "THE METAL OF THE FUTURE"
posted on
Jan 13, 2011 02:17PM
Edit this title from the Fast Facts Section
“All the great ways we have to generate electricity – solar, wind, geothermal – they’re nothing without an efficient way to store it…This is the biggest, most significant thing we’re facing this century.”
-Ian Clifford, CEO of Zenn Motor Co.
VANADIUM REDOX BATTERIES
The Vanadium-Redox Flow Battery (VRB), invented at the University of New South Wales in Australia, is structurally and chemically different from any other battery in ways that could help overcome current shortcomings in battery technologies. VRBs are nontoxic, have an indefinite lifespan, and do not self-discharge while idle or generate high amounts of heat while charging.
Vanadium is stored in two separate containers in liquid form - one is charged with energy and one has a depleted energy charge. When new energy is gathered, non-charged Vanadium gets re-energized and stored until needed.
The main advantage is It can absorb and release huge amounts of electricity instantly and do so over and over again, making it the only battery technology today capable of connecting directly to power grids and stream lining the intermittent flow of energy from wind turbines and solar cells while being fully scalable to meet almost any capacity.
Vanadium has also proven to be an effective additive to existing batteries in small scale applications. For instance, in the case of electric cars, vanadium, when combined with lithium, acts as a ‘supercharger’ that increases the battery’s energy density — and in the case of vehicles, this equates to the distance a car can travel.
Click here for video on the Subaru G4E...
Subaru’s recently revealed G4e concept car uses a vanadium- lithium battery, which dramatically extends the travel distance from 40 kilometres to 200 km on a single charge. Discover Magazine recently (October '08) called vanadium "The element that could change the world."
The vanadium redox (and redox flow) battery 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. The present form (with sulfuric acid electrolytes) was patented by the University of New South Wales in Australia in 1986. The first successful demonstration and commercial development was by Maria Skyllas-Kazacos and co-workers at the University of New South Wales in the 1980s. The vanadium redox battery exploits the ability of vanadium to exist in solution in four 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 are 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.
A vanadium redox battery consists of an assembly of power cells in which the two electrolytes are separated by a proton exchange membrane. 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 may be prepared by any of several processes, including electrolytically dissolving vanadium pentoxide (V2O5) in sulfuric 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 one company has focused on electric vehicle applications, using rapid replacement of electrolyte to refuel the battery.
When the Vanadium battery is charged, the VO2+ ions in the positive half-cell are converted to VO3+ 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. Round trip efficiency in practical applications is around 65-75%.
Generation 2 Vanadium redox batteries (Vanadium/polyhalide) may approximately double the energy density and increase the temperature range in which the battery can operate.
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.
Currently installed vanadium batteries include:
Vanadium redox batteries (VRB) are a flow battery perfectly suited for grid storage and larger scale applications.. They can store megawatt-hours worth of energy and can produce megawatt levels of power. VRBs can economically store and supply large amounts of electricity on demand. It is a long-life, cost effective, low maintenance technology that can be reused indefinitely and therefore has no carbon footprint. VRBs are highly efficient at backing up intermittent or less reliable forms of alternative energy which gives them a range of use for storing diesel power, wind and solar energy and nuclear electricity. The Chinese company Prudent Energy recently purchased patents and assets from the Canadian company, VRB Power Systems, in its plans to develop and commercialize VRBs throughout China and North America. Several other companies, such as Sumitomo Electric in Japan, Cellstrom in Germany and Cellenium in Thailand have already implemented VRB technology over the past decade. VRB inventor, Maria Skyllas Kazakos is now developing next generation VRB`s that will ensure a smaller and more effective battery, which will in turn open up brand new applications such as transportation systems(Buses, Commuter Trains), and certain commercial electronics.
There is a consensus among researchers that a newer technology, Vanadium-Lithium Ion represents the best potential lithium battery. In this battery, Vanadium is used in the form of Vanadium phosphate cathodes in Lithium-ion batteries. It can hold more per charge (approx 22%) than the standard Lithium-Cobalt oxide battery. It has a higher voltage-around 4.7 volts or 4.8 volts-compared to about the 3.7 that the standard battery produces today. For electric cars, this means superior power and acceleration as well as more range because of increased capacity. Threat of explosion, a potential danger of Lithium-Cobalt is also alleviated as the Vanadium-Lithium battery produces much less heat while charging. Furthermore, Vanadium-Lithium-Ion produces more power in a smaller space, which helps with size requirements of newer vehicles. Already lower in price than the Lithium Cobalt Oxide battery this battery could be the “Next Generation,” extending life of consumer electronics and making electric cars a reality.
As the last decade has seen a significant amount of development work on Vanadium batteries, implementation for stationary power and additional applications such as electric vehicles is well underway. Alternative energy and next generation technologies such as solar and wind are increasing every year. Many of these technologies capture energy as it is available and store it for use when needed. Increased storage requirements of these new technologies are expected to impact the demand for Vanadium-based batteries significantly. Vanadium batteries have several advantages over Lead acid, Nickel Metal, Lithium Ion Batteries, including:
Several car manufacturers now have a Vanadium battery project underway. With the race for the perfect car battery underway, Vanadium seems to have some clear advantages by itself and in combination with Lithium. Vanadium Redox is the best suited for grid storage as it can store electricity indefinitely, act as a transformer and release electricity immediately whenever needed.
The U.S. Department of Energy's Pacific Northwest National Laboratory estimates that 84% of cars, trucks and SUV's could be powered by the U.S. electrical grid overnight during off-peak usage without a single additional power plant being built.
The necessity to reduce the western world's dependence of foreign oil and the increase in worldwide protocol to reduce carbon dioxide and other greenhouse gasses.
The United States
“Next generation” Vanadium battery technologies could create a brand new market for Vanadium in the near future and could play a major part in solving the global energy crisis.
Vanadium Redox Flow Battery Allows charging and discharging of energy as available and as needed and is already being implemented in various countries for power grids, factories and various other applications.
Vanadium-Lithium Ion Battery Is fast approaching commercial implementation for various electronics and could make electric vehicles commercially viable.
These applications would require a large supply of vanadium. Below is a more detailed description of these two emerging technologies that promise lower cost energy and a cleaner environment.
1) Vanadium Redox Flow Battery
2) Vanadium-Lithium Ion battery
In the lab, Lithium vanadium oxide anodes, paired with lithium cobalt oxide cathodes, have nearly three times the volumetric en