What is the connection between Saudi Arabia and advanced lithium-ion batteries that could revolutionize electric cars as we know them?
His name is Yi Cui.
Electric cars often seem to have the world against them. While gasoline is incredibly energy dense, with 12,000 Wh/kg, lithium-ion batteries have a mere 100-150 Wh/kg. Now, thanks to EVs lightening up other portions of the car, you really only need about 350 Wh/kg to outrange an equivalent weight gasoline car. Still, a severalfold improvement in energy density may seem like a long way to go. Thankfully, many new technologies promise to push us close to or past that mark. Without a doubt, the most intriguing of these is the silicon nanowire anode developed by a team led by Stanford's Yi Cui, assistant professor of nanomaterials science and engineering
A traditional lithium-ion battery has a lithium cobalt oxide cathode, an electrolyte, a porous polymer membrane to prevent short circuits, and a graphite anode. When charging and discharging, lithium ions move from one side to the other through the separating membrane. The bulk of the battery's size and mass is comprised of the cathode and the anode. Modern lithium ion batteries are a thing of beauty in EVs -- 99.9% charge/discharge efficient (compared to 50-70% for NiMH), largely safe and long lasting (unlike their laptop battery counterparts), more energy dense than NiMH, no finicky charge/discharge profiles like in NiMH, no need for active cooling during charge/discharge like NiMH, no memory effect, and so forth. The open-ended question is, of course, mass production, but it seems unlikely that this will hold up EVs. Still, a significant increase in energy density would be quite welcome.
Dr. Cui's nanowire battery swaps the graphite anode with one made of silicon nanowires. Silicon is an amazing absorber of lithium ions, holding ten times as much by weight. In fact, it's too good -- it absorbs enough that it swells, cracks, crumbles, and is rendered nearly useless. What the Stanford team discovered is that when one uses silicon nanowires instead of bulk silicon, the wires stretch but do not crack. The test battery retained eight times the normal lithium density in the anode after the first charge with minimal signs of degradation after that. It is currently undergoing extensive cycle testing, and the team believes it will last for over a thousand cycles, and should be able to be mass produced at prices cheaper than existing lithium ion batteries.
It's important not to understate how big of a deal this is. While this is only an anode advance, on its own it still allows several times better energy density, and with an equivalent cathode advance, eight times the energy density of existing lithium ion batteries. An EV that can go 200 miles on existing batteries could go 600 miles with an equivalent mass of these, and 1600 miles with an equivalent cathode advance (and cathodes are indeed being strongly studied). With the high surface area and low internal resistance, rapid charging should be easy with these batteries. The news made a big buzz for a while, then dried up. The last I heard from the group, they were seeking a way to commercialize the technology and felt they could bring it to the market within five years -- if only they could find funding or a private partnership.
That is, until today, when his name turned up in a press release from King Abdullah University of Science and Technology (KAUST) It appears that the same Yi Cui who led the nanowire battery team, whose work largely revolves around silicon nanowires, is the first recipient on the list of a Global Research Partnership (GRP) grant announced by His Excellency Minister Abi Ibrahim Al-Naimi, Saudi Arabia's Minister of Petroleum and Mineral Resources and Chairman of the Board of Trustees of KAUST. While the release lacks specifics as to what their grant will cover, it's safe to say that none of Dr. Cui's other work has garnered nearly as much public or commercial interest as that of his nanowire battery work -- and this, coming just months after he stated he was looking for funding to develop the technology, makes it seem unlikely that they are funding any other project of his.
What are GRP grants? According to the website, they are five year grants (curiously, the amount of time Dr. Cui estimated would be needed to commercialize the technology) given to teams around the world that allow the researchers to continue their efforts at their home institutions while working at the same time with teams at the KAUST research park (on topics that include "renewable and sustainable next-generation energy sources"). The KAUST research park, in turn, is designed to be a Saudi Arabian "Skunk Works", where revolutionary technologies are invested in, nurtured, and then partnered with by major Saudi Arabian companies, such as Saudi Aramco, SABIC and SWCC. While the GRP grants are administered with respect to the hosts' IP rights, it seems that given KAUST's "if it works, we want it" attitude towards research conducted there, Dr. Cui not only has his five years of development money down, but potential commercial partners as well.
Now, KAUST may not see the technology as an attempt to produce better automotive batteries. For example, given their focus on solar power as a next-generation electricity source due to their near ideal location, it could be little more than an attempt to lower battery costs for nighttime solar electricity storage. Nonetheless, how ironic it would be if the nation leading us into the future, leading us away from oil and towards efficient, clean, renewable power was none other than Saudi Arabia.