Morgan - 23-10-2012 at 21:10
I was watching the Colbert Report which had a segment on the liquid metal battery.
http://video.tvguide.com/Colbert+Report/Donald+Sadoway/16309...
So then I started reading Wiki about these types of batteries and the first was way back in the 40's, where one was designed/planned for the V1
pulsejet.
"Referred to as thermal batteries, the electrolyte is solid and inactive at normal ambient temperatures. The origin of the thermal battery dates back
to World War II when German scientist Dr. Ing. Georg Otto Erb developed the first practical cells, using a salt mixture as an electrolyte. Erb
developed batteries for several military applications, including the V-1 flying bomb and the V-2 rocket, and artillery fuzing systems. However, none
of these batteries entered field use before the end of World War II. Following the end of the war, Erb was interrogated by British intelligence and
his work was reported in a document titled "The Theory and Practice of Thermal Cells". This information was subsequently passed on to the United
States Ordnance Development Division of the National Bureau of Standards.[3]"
"These batteries have been used for ordnance applications (e.g., proximity fuzes) since World War II and, subsequent to that, in nuclear weapons. They
are the primary power source for many missiles such as the AIM-9 Sidewinder, MIM-104 Patriot, BGM-71 TOW, BGM-109 Tomahawk and others. In these
batteries the electrolyte is immobilized when molten by a special grade of magnesium oxide that holds it in place by capillary action. This powdered
mixture is pressed into pellets to form a separator between the anode and cathode of each cell in the battery stack. As long as the electrolyte (salt)
is solid, the battery is inert and remains inactive. Each cell also contains a pyrotechnic heat source which is used to heat the cell to the typical
operating temperature of 400 - 550C."
"The high power capability is due to the very high ionic conductivity of the molten salt, which is three orders of magnitude or more greater than that
of sulfuric acid in a lead-acid car battery."
http://en.wikipedia.org/wiki/Molten_salt_battery
So then I reviewed the reactivity series to see where antimony is and I also checked it's price per pound. Sadoway's battery uses a molten layer of
magnesium floating on top, then molten salt, and at the bottom molten antimony. But after reading about some other thermal batteries I came across
Sumitomo's development in the same Wiki article above. So what salt might they be using I wonder?
"Sumitomo developed a battery using a salt that is molten at 57 °C (135 °F) far lower than sodium based batteries. The battery offers energy
densities as high as 290 Wh/L. The battery employs only nonflammable materials and will not ignite on contact with air, nor is there thermal runaway.
This eliminates waste-heat storage or fire- and explosion-proof equipment, and allows closer packing of cells. The company expects that the battery
requires half the volume of lithium-ion batteries and one quarter that of sodium-sulfur batteries.[13]"
Here's Donald Sadoway on TED. He describes and draws his battery where Mg forms an alloy with Sb and all around the 8 minute mark.
http://www.ted.com/talks/donald_sadoway_the_missing_link_to_...
[Edited on 24-10-2012 by Morgan]
Morgan - 25-10-2012 at 11:01
MIT team calls initial performance results of magnesium-antimony liquid metal battery “promising”
http://www.greencarcongress.com/2012/01/sadoway-20120123.htm...
"Antimony was ranked first in a Risk List published by the British Geological Survey in the second half 2011. The list provides an indication of the
relative risk to the supply of chemical elements or element groups required to maintain the current British economy and lifestyle."
"Also, antimony was identified as one of 12 critical raw materials for the EU in a report published in 2011, primarily due to the lack of supply
outside China."
"Reported production of antimony in China fell in 2010 and is unlikely to increase in the coming years, according to the Roskill report. No
significant antimony deposits in China have been developed for about ten years, and the remaining economic reserves are being rapidly depleted."
"According to statistics from the US Geological Survey (USGS), current global reserves of antimony will be depleted in 13 years. However, the United
States Geological Survey expects more resources will be found."
http://en.wikipedia.org/wiki/Antimony#cite_note-81
Reader comment
"A great solution to a non-problem, since it is far cheaper to use flexible generation, demand-side managment, and a host of other techniques to
integrate wind and solar power than to use these ridiculously expensive battery storage technologies. Batteries are also far too small to compete with
conventional storage, like pumped hydroelectric, and if I had a nickle for every "revolutionary" technology that was going to be commercialized in
just 5 years, the Federal Reserve would be asking me for a bailout."
http://www.greenoptimistic.com/2009/03/08/mit-liquid-battery...
AEP unplugs sodium sulfur battery
http://wvwindreport.wordpress.com/2012/09/06/aep-unplugs-sod...
[Edited on 25-10-2012 by Morgan]
Morgan - 27-10-2012 at 06:04
Some competition.
"The work is showing extraordinary results. Independent full cell tests reveal unrivaled performance characteristics, with an energy density of
525WH/Kg and specific anode capacity 1,250mAh/g. In contrast, most commercial LIBs have an energy density of between 100-180WH/kg and a specific anode
capacity of 325mAh/g. “This equates to more than a 300% improvement in LIB capacity and an estimated 70% reduction in lifetime cost for batteries
used in consumer electronics, EVs, and grid-scale energy storage,” said CalBattery CEO Phil Roberts."
http://www.virtual-strategy.com/2012/10/26/new-lithium-si-gr...
http://www.clbattery.com/#!advanced-technology/vstc1=vlf-bat...