The reason lithium-metal batteries are so promising is because of the excellent energy density of pure lithium metal.
Scientists in South Korea have made a breakthrough in battery research. This is claimed to help overcome major bottlenecks in energy storage. The team’s progress overcoming technical issues hindering lithium-metal battery architecture could pave the way for batteries with 10 times the capacity of current devices.
The reason lithium-metal batteries are so promising is because of the excellent energy density of pure lithium metal. Scientists hope to swap the graphite used for the anode in current lithium batteries for the “dream material,” although this comes with some tricky problems to overcome.
One of the main problems has to do with needle-like structures called dendrites, which form on the anode surface when the battery is charged. This penetrates the barrier between the anode and cathode, and quickly causes the battery to short-circuit, or even burn out.
Therefore, much of the research in the battery field has focused on preventing the formation of dendrites. Much of this focus on forming the protective interface of the anode and the battery electrolyte, which carries charge back and forth between the electrodes.
“The formation of lithium dendrites is highly dependent on the surface properties of the lithium anode. An important strategy for lithium-metal (LMB) batteries is establishing an efficient solid electrolyte interface (SEI) on the lithium surface,” said study author Professor Yong Min Lee of South Korea’s Daegu Gyeongbuk Institute of Science and Technology (DGIST).
Reported from Gizmochina (5/6), Lee and his colleagues have approached this problem using lithium metal powder as a starting point. This method creates a higher surface area and allows the manufacture of both thin and wide electrodes. However, one drawback of this technique is the nature of the uneven surface, potentially damaging the battery.
The solution, scientists at DGIST have added lithium nitrate. Pre-embedding of the compound during the fabrication process allowed the team to fabricate an ultra-thin lithium metal anode with a smooth and uniform interface layer on the surface. This is proven to keep the battery stable over 450 charge cycles, during which it will maintain 87% of its original capacity.