The Helmholtz Institute in Ulm (Germany) has developed an innovative lithium metal battery for electric vehicles. The new battery has twice the specific storage density of conventional lithium-ion batteries.
This was reported by RBC-Ukraine with a link to the website of the Karlsruhe Institute of Technology.
Researchers at the Helmholtz Institute Ulm (HIU), founded by the Karlsruhe Institute of Technology (KIT) in collaboration with the University of Ulm, have developed a new lithium metal battery with an extremely high energy density – up to 560 Wh / kg.
For comparison: the well-known lithium-ion batteries have a capacity of 285, solid-state – 400-500 watt-hours per kilogram.
The engineering team used a promising combination of cathode and electrolyte: a nickel-rich cathode stores a large amount of energy per unit mass, while an ionic liquid electrolyte ensures that capacity is largely retained over many charge cycles.
Lithium metal batteries are more attractive as a solution for storing energy with a higher capacity than modern lithium-ion batteries, but their stability is an issue as electrode materials react with conventional electrolyte systems.
Laminated cathode with low cobalt content and high nickel content provides high energy density. However, for a commercially available organic electrolyte, such poor stability is unacceptable. Therefore, the researchers instead used a non-volatile non-flammable ionic liquid electrolyte with two anions.
By using an ionic liquid electrolyte, structural changes in the nickel-rich cathode can be largely avoided; 88% of battery capacity is retained after 1000 charge cycles.
The lithium metal battery with the new components initially has a capacity of 214 mAh. The efficiency of a new battery is 99.94% on average. But the serial production of the new development is still very far away. The battery has to go through a long cycle of endurance tests in various operating conditions.