‘Lifetime and energy density of solid-state batteries increase with silver coating’

Researchers from the Samsung Advanced Institute of Technology and the Samsung R&D Institute Japan say they can improve the safety, longevity and energy density of solid-state batteries by applying a layer of silver and carbon in the anodes.

According to the researchers, solid-state batteries with anodes made from lithium metal are potential replacements for conventional lithium-ion batteries, but there is the problem of lithium metal being deposited on the anodes during the charging process, in the form of dendrites. These are crystal structures that grow between the anode and cathode and can cause short circuits and heat generation, which can lead to a fire. According to the researchers, this deposition of lithium can be effectively regulated by a composite of silver and carbon.

If that thin layer is applied in a battery cell, the researchers believe that will result in a greater capacity, longer lifespan and better safety. The nanocomposite layer of silver and carbon is 5 micrometers thick; according to the scientists, this is very thin and that makes it possible to limit the thickness of the anode and increase the energy density to more than 900Wh/L. They also state that this layer made it possible to make a prototype that is twice as small as a conventional lithium-ion battery.

In the press release, Samsung states that this discovery could lead to further adoption of electric cars. The prototype battery cell the researchers have developed should enable a range of 800 km for an electric car, with a lifespan of more than a thousand charges. The so-called state of health of the battery would be 95 percent after 600 charge cycles and 89 percent after a thousand cycles. The discharge capacity that was achieved was 5870mAh and the energy density at 942Wh/L, which could rise to more than 1000Wh/L.

The research was published in the scientific journal Nature Energy, under the title High-energy long-cycling all-solid-state lithium metal batteries enabled by silver–carbon composite anodes.