• 4 minutes Energy Armageddon
  • 6 minutes How Far Have We Really Gotten With Alternative Energy
  • 10 minutes Russia Says Europe Will Struggle To Replace Its Oil Products
  • 17 mins GREEN NEW DEAL = BLIZZARD OF LIES
  • 15 hours Reality catching up with EV forecasts
  • 8 days "Natural Gas Price Fundamental Daily Forecast – Grinding Toward Summer Highs Despite Huge Short Interest" by James Hyerczyk & REUTERS on NatGas
  • 3 days 87,000 new IRS agents, higher taxes, and a massive green energy slush fund... "Here Are The Winners And Losers In The 'Inflation Reduction Act'"-ZeroHedge
  • 8 days A Somewhat Realistic View of the Near Future for Electric Vehicles Worldwide
  • 14 days The Federal Reserve and Money...Aspects which are not widely known
Brian Westenhaus

Brian Westenhaus

Brian is the editor of the popular energy technology site New Energy and Fuel. The site’s mission is to inform, stimulate, amuse and abuse the…

More Info

Premium Content

Tokyo Researchers Discover New Mechanism To Stabilize Lithium Batteries

  • A Tokyo-based research team has discovered a new mechanism to stabilize lithium batteries.
  • Lithium metal batteries are a promising technology with potential to meet the demands for high-energy-density storage systems.
  • The study was carried out in collaboration with the Nagoya Institute of Technology

A University of Tokyo team of researchers has discovered a new mechanism to stabilize the lithium metal electrode and electrolyte in lithium metal batteries. This new mechanism, which does not depend on the traditional kinetic approach, has potential to greatly enhance the energy density of batteries increasing the amount of energy stored relative to the weight or volume.

The team’s findings have been published in the journal Nature Energy.

Lithium metal batteries are a promising technology with potential to meet the demands for high-energy-density storage systems. However, because of the unceasing electrolyte decomposition in these batteries, their Coulombic efficiency is low. The Coulombic efficiency, also called the current efficiency, describes the efficiency by which electrons are transferred in the battery. So a battery with a high Coulombic efficiency has a longer battery cycle life.

Atsuo Yamada, a professor in the Department of Chemical System Engineering at the University of Tokyo said, “This is the first paper to propose electrode potential and related structural features as metrics for designing lithium-metal battery electrolytes, which are extracted by introducing data science combined with computational calculations. Based on our findings, several electrolytes, which enable high Coulombic efficiency, have been easily developed.” The team’s work has the potential to provide new opportunities in the design of next-generation electrolytes for lithium metal batteries.

In lithium-ion batteries, the lithium ion moves from the positive electrode to the negative electrode through the electrolyte during charge and back when discharging. By introducing high-energy-density electrodes, the battery’s energy density can be improved. In this context, many studies have been conducted over the past decades to change the graphite negative electrode to lithium metal. However, the lithium metal has a high reactivity, which reduces the electrolyte at its surface. Because of this, the lithium metal electrode shows a poor Coulombic efficiency.

To overcome this problem, scientists have developed functional electrolytes and electrolyte additives that form a surface protective film. This solid electrolyte interphase has an impact on the safety and efficiency of lithium batteries. The surface protective film prevents direct contact between the electrolyte and lithium metal electrode, thereby kinetically slowing the electrolyte reduction. Yet, until now, scientists had not fully understood the correlation between the solid electrolyte interphase and the Coulombic efficiency.

ADVERTISEMENT

Scientists know that if they improve the stability of the solid electrolyte interphase, then they can slow the electrolyte decomposition and the battery’s Coulombic efficiency is increased. But even with advanced technologies, scientists find it difficult to analyze the solid electrolyte interphase chemistry directly. Most of the studies about the solid electrolyte interphase have been conducted with indirect methodologies. These studies provide indirect evidence, therefore making it hard to develop the electrolyte stabilizing lithium metal that leads to a high Coulombic efficiency.

The research team determined that if they could upshift the oxidation-reduction potential of the lithium metal in a specific electrolyte system, they could decrease the thermodynamic driving force to reduce the electrolyte, and thus achieve a higher Coulombic efficiency. This strategy had rarely been applied in developing batteries with lithium metal. “The thermodynamic oxidation-reduction potential of lithium metal, which varies significantly depending on the electrolytes, is a simple yet overlooked factor that influences the lithium metal battery performance,” explained Atsuo Yamada.

The team studied the oxidation-reduction potential of lithium metal in 74 types of electrolytes. The researchers introduced a compound called ferrocene into all the electrolytes as an IUPAC (International Union of Pure and Applied Chemistry)-recommended internal standard for electrode potentials. The team proved that there is a correlation between the oxidation-reduction potential of lithium metal and the Coulombic efficiency. They obtained the high Coulombic efficiency with the upshifted oxidation-reduction potential of lithium metal.

Looking ahead to future work, the research team’s goal is to unveil the rational mechanism behind the oxidation-reduction potential shift in more detail. “We will design the electrolyte guaranteeing a Coulombic efficiency of greater than 99.95%. The Coulombic efficiency of lithium metal is less than 99%, even with advanced electrolytes. However, at least 99.95% is required for the commercialization of lithium metal-based batteries,” said Atsuo Yamada.

The study was carried out in collaboration with the Nagoya Institute of Technology.

ADVERTISEMENT

***

A quick look at the Battery section of this website shows that there is a huge world wide effort to get to a commercial lithium metal battery. So far, there isn’t a technology mature enough that a manufacturer is willing to build up a production line.

But the advantages are many and impressive. Just what stops manufacturers is likely the dendrite issue, those growths that short a battery out often with dire consequences.

One can be confident that the day will come that the lithium metal chemistry is top of the market. Perhaps a combination of the various concepts might get the job done. Its going to take a while and a lot of money.

But once the confidence is there, the investing takes off and there are competing technologies there will be much better batteries for consumers to use.

By Brian Westenhaus via New Energy and Fuel

More Top Reads From Oilprice.com:


Download The Free Oilprice App Today

Back to homepage


ADVERTISEMENT


ADVERTISEMENT



Leave a comment

Leave a comment




EXXON Mobil -0.35
Open57.81 Trading Vol.6.96M Previous Vol.241.7B
BUY 57.15
Sell 57.00
Oilprice - The No. 1 Source for Oil & Energy News