On Fri, 2002-09-20 at 23:22, Michael Hurley wrote: > I found a link recently pointing to a project at the University of > New South Wales to create an apparently new type of battery. They > call it a Vanadium Redox Battery. I claim to know absolutely nothing > about battery chemistry, so I have no idea what the potential of this > technology is, but I thought I'd pass it on to the list as I don't > remember seeing it discussed before. It seems to recycle the > electrolyte somehow to "refuel" in a way. Something like you can > charge it normally or replace the electrolyte to replace capacity. > Any observations, thoughts or rants? > > http://www.ceic.unsw.edu.au/centers/vrb/
I saw a Beyond 2000 show about this technology many years ago. The cool thing is the "instant recharge" by stopping at a "solution station" and exchanging the spent solution for freshly charged solution. This means that for normal weekly driving, you charge at home like a regular battery, but you have the option at any time to take an extended trip (assuming the refueling infrastructure is in place). Not to mention the fact that since all cells - being "fed" by the same tanks of solution - have the exact same SOC, you don't need all the fancy chargers that know how to do equalization - and no battery "watering". Considering that the cell itself has an incredibly long life, as well as the motor, this would be an excellent "real world" drivetrain. The only part that "wears out" regularly is the solution - which is replaceable or rechargeable. I just wonder when it will be available for public consumption, considering the program started in 1984, and there have been commercial applications in place since the '90s. According to the site, the current issue is energy density - at 25kW/kg. They have some research that gets to 35kW/kg, but expect that they would need to get to 50kW/kg to be viable for consumer EVs. But the page was last updated Feb 6, 2001, and the news page in 1998, so who knows the current status. How do these energy density numbers match up to current batteries used by EVers? The site points to http://www.pinnaclevrb.com.au/, but they don't seem to have any products available. Lonnie Borntreger
