Li-S technology stands out as a potential alternative for Li-ion batteries due to the improved energy density, particularly in applications where the specific energy density is important [1,2]. OXIS Energy is currently developing Li-S batteries that outperform other battery technologies available in the market nowadays. Among the different challenges to obtain a high-performance Li-S battery, the issues related to metallic Li electrode are a limiting factor [3]. Among others, the continuous degradation reactions on Li surface and dendrite formation result in poor cycle life and arise safety hazards. Different approaches have been proposed to overcome these effects, such as the use of additives on the electrolyte, the development of structured composite Li anode or the formation of an artificial solid electrolyte interphase (SEI) [3,4]. Direct deposition of protective coatings on the surface of Li electrodes by means of Magnetron Sputtering is an easy and potentially scalable method to successfully produce thin and homogeneous layers with upgraded properties as an artificial SEI [5]. In this work current research activities in sputter deposited coatings being developed at OXIS Energy will be described, focusing both on the deposition process of coating materials and the electrochemical response of coated electrodes.
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[2] Fotouhi, Abbas, et al. "Lithium-Sulfur Battery Technology Readiness and Applications—A Review." Energies 10.12 (2017): 1937.
[3] Cheng, Xin-Bing, Jia-Qi Huang, and Qiang Zhang. "Li metal anode in working lithium-sulfur batteries." Journal of The Electrochemical Society 165.1 (2018): A6058-A6072.
[4] Cheng, Xin‐Bing, et al. "A review of solid electrolyte interphases on lithium metal anode." Advanced Science 3.3 (2016): 1500213.
[5] Li, Juchuan, et al. "An artificial solid electrolyte interphase enables the use of a LiNi0. 5 Mn1. 5 O4 5 V cathode with conventional electrolytes." Advanced Energy Materials 3.10 (2013): 1275-1278.