New breakthrough in solid battery: energy density will reach twice that of lithium-ion batteries

To some extent, all modern lithium batteries are a compromise, because the original concept is to make lithium metal batteries that can store more energy in the same volume. But the problem is that the durability of lithium metal batteries is very poor. Lithium-ion batteries transfer lithium ions from the cathode to the anode during the charging process, and are extremely energy-intensive in this process. This requires a separator in the middle to allow only lithium ions to pass through, and a conductive electrolyte. In lithium metal batteries, the shuttled lithium ions simply form pure metal lithium on the anode side. However, lithium has a tendency to form a dendritic structure, which can penetrate the cathode and cause a short circuit in the battery. And because the liquid electrolyte used in these batteries is flammable, it may catch fire when short-circuited. One of the solutions is to use graphite anodes. The ordered structure of graphite provides space for lithium ions, which greatly reduces the risk of dendrite formation. But this kind of graphite can occupy nearly half of the battery's volume without increasing the energy density. Although the safety of the battery is guaranteed, the performance is impaired. Recently, QuantumScapehas, a closely watched battery technology company, announced that it has solved this problem. The reason why it has attracted much attention is that it has not only received investment from Bill Gates, SAIC, and Volkswagen, but also has a strong team, including a former director of Google, a chief scientist of Volkswagen, and a former CTO of Tesla. One way to improve lithium batteries is to manufacture electrolyte materials to replace the flammable components in the battery and reduce unnecessary chemical reactions between the electrolyte and other battery materials. These chemical reactions will cause the performance of the battery to decline over time. QuantumScapehas has been researching solid electrolytes for about ten years. Previously, the project was spun off from a laboratory at Stanford University and received some funding from the US Department of Energy. In the press conference and video call, QuantumScape showed the battery it made and provided a lot of test data. However, these tests have not been independently verified by a third party. QuantumScape said that compared with traditional lithium batteries, its solid-state batteries will increase the cruising range of electric vehicles by 80%. Moreover, after 800 charging cycles, more than 80% of the capacity can still be maintained. In terms of safety, solid-state batteries have no risk of fire. And the volumetric energy density will exceed 1,000 watt-hours per liter, which is almost twice the density of commercial lithium battery packs. According to some current information, the new battery displayed this time is a pouch battery with a single-piece cathode layer, solid electrolyte layer and anode contact foil. The cathode material may be a nickel-manganese-cobalt cathode material, which is currently the most common cathode material. During the charging process, lithium ions leave the cathode, pass through the solid electrolyte layer, and are plated on the anode foil to form pure lithium. This does cause the thickness of the battery to expand slightly during the charging process, but QuantumScape says that the problem is not big because it only expands in one direction. It seems that QuantumScape's research goes further than laboratory results. The company said that about five years ago, it determined the ceramic material for the solid electrolyte and has been studying the manufacturing process ever since. Although the test battery pack shown by QuantumScape contains a battery sandwich about the size of a playing card, the company said its actual battery cell will look more like a deck of playing cards with many stacked layers. For this reason, QuantumScape needs to process these materials on a large scale. This is not just a matter of mass production, while maintaining perfect quality. QuantumScape has received a huge investment, and has also established a cooperation agreement with Volkswagen to extend the cooperation to the manufacturing stage. The company plans to use solid-state batteries to enter the electric vehicle market in 2024 or 2025. Disclaimer: Some pictures and content of articles published on this site are from the Internet. If there is any infringement, please contact to delete.