What do a 2005 Jeep Cherokee and a Tesla Model S have in common?
Outside of the basics — four wheels, windows, a roof, etc. — there shouldn’t be much of anything else.
Unfortunately for their owners, these two have something else they share:
Lithium batteries were the cause for both fires. The Tesla S comes with a large array of them. The 2005 Cherokee simply had a smartphone sitting in it.
Fires are a fatal flaw of lithium ion battery designs, and are raising the question of if they are what we should use to power our phones and cars.
Then there are the even more power-hungry applications for batteries in the near future. Trucks and home power storage are next, and put far more expensive property at risk.
The reality is there is no way out. Lithium battery production infrastructure would take tens of billions to replace.
Plus, there are no other designs that can provide the same power density at anything close to a comparable price at scale.
We may be stuck with lithium batteries for decades to come, but not the fatal flaw that many lithium battery designs have today.
Two new designs are already showing a lot of promise. One is completely fireproof, while another is inspired by the human intestine to drive up energy density without increasing the risk of fire.
Both show how we’ll engineer our way out of this problem, without compromising weight or power demand.
Lithium Ceramics
The fire issue with current battery designs has attracted the attention of the Department of Energy, which has dedicated tens of millions of dollars to creating a safer alternative.
At a small research lab at the University of Maryland, one research project is showing promising results.
Take a look at the picture below. The disc on the left is coated with a carbon-based solution, typical of what’s used in all of the lithium-ion batteries powering today’s smartphones. The disc on the right is a lithium-conducting ceramic.
As Eric Wachsman, engineering professor and director of the Energy Research Center explained to CBS News:
“Because it’s ceramic, it’s absolutely inflammable. You cannot burn the ceramic.
“So this size is fine for little batteries, the little coin cells you might see in a hearing aids or whatever — small little round ones. But to get to the larger size, it’s just a matter of scaling up the size.
“We’ve been contacted by numerous companies all over the world, both by email and phone. “We have manufacturing partners and we expect to have a product in the next few years.”
Gut Inspired Design
The other promising design coming down the pike ditches carbon as well, this time in favor of sulfur.
Lithium-sulphur battery technology has a lot of potential, with up to five times the energy density of lithium-ion solutions used today at a lower cost.
Unfortunately, the designs tend to be short-lived, with active material being lost during the repeated charge-discharge cycle.
To overcome the issue, the Cambridge team — working in collaboration with Beijing Institute of Technology researchers — took inspiration from finger-like protrusions on the lining of the human intestine, called villi.
The researchers created a layer of tiny zinc oxide wires that mimic the villi structure, and placed it on the surface of the lithium-sulphur battery’s cathode.
In testing, they found that the villi-like layer of wires, with its high surface area, formed strong chemical bonds with the poly-sulphides in the battery, trapping them, and allowing the material to be reused.
Tip of the Iceberg
These two major developments come on the heels of several other revolutionary breakthroughs for battery technology.
Microbe-based batteries have been made in the lab, recharging through electricity generated by bacteria.
Then there is the “junkyard battery,” based on a millenia-old blueprint, and built with scrap steel and brass that could store energy at levels approaching lead-acid car battery levels.
But none of the novel designs can offer what improved lithium battery designs can.
That microbe battery? It is very weak and could only be recharged 15 times.
The junkyard design? It lasts, but it only has an energy density of 20 Watt hours to kilogram, as compared to 100 to 265 Wh/ kg for the batteries in smartphones.
In short, lithium isn’t going anywhere.
With battery demand in the coming years and decades soaring at an unprecedented rate, there is no time to completely change production lines without massive disruptions.
Thankfully, while today’s lithium batteries may have critical design flaws, tomorrow’s will not.
