Land, and even more so air electric transport, needs batteries that can store more energy without becoming too heavy. A team of scientists from Germany demonstrated a new lithium metal battery with an energy density of 560 Wh / kg, which is 2 times the density of existing commercial lithium-ion batteries. At the same time, the prototype of the new battery degrades very slowly – it lost only 12% of its capacity after 1000 charge-discharge cycles.
Specialists of the Karlsruhe Institute of Technology and the Institute. Helmholtz in Ulm began to search for a solution to the problem of low energy density of batteries with a nickel-rich and cobalt-poor NCM88 cathode and an organic electrolyte LP30. However, despite the fact that the cathode performed well in terms of energy density, this battery architecture turned out to be unstable: cracks appeared in the cathode, and the electrolyte reaction destroyed the structure. In addition, a thick lithium layer formed on the anode, New Atlas says.
Then the scientists chose the alternative – LP30 electrolyte, a non-volatile, poorly flammable ionic liquid electrolyte (ILE). He has proven to be able to largely resist structural defects in the cathode and protect the battery from fatal electrochemical reactions.
The test results showed that a lithium metal battery with this architecture has an energy density of 560 W * h / kg. According to analysts, overcoming the 500 W * h / kg indicator should become an important stage in the development of electric transport. The energy density of modern lithium-ion batteries is 250-300 W * h / kg.
In terms of service life, the new battery also showed its best side – it retained 88% of the initial capacity of 214 mAh / g at the cathode after 1000 cycles. And in terms of current efficiency, the battery efficiency was 99.94%, as in existing commercial lithium-ion batteries.