Tailor-Made Electrolyte Solutions by E-Lyte Innovations for Advanced Lithium Ion Batteries: Towards Sustainable Electrochemical Energy Storage - Everywhere and Anytime

摘要

In recent years, the lithium ion battery (LIB) has conquered many new applications such as automotive, medical engineering, consumer electronics, robotics or aviation. Each application places different demands on the battery. Some applications require a longer life, high safety, other applications require high power or have a high energy demand. Due to the different materials used in LIBs, not all requirements can be met by one battery setup. Therefore, an adjustment of the LIB is required to address each application with maximum efficiency. In this regard, the development of tailor-made electrolyte solutions, which strongly depend on the specific field of application and the corresponding cell chemistry, is a key strategy for success. The electrolyte as heart blood of the battery interconnects anode and cathode, enabling the batteries functionality by ensuring a rapid transport of ionic charge carriers within the cell as well as the formation of essential interphases. A very promising approach lies in the addition of small amounts of functional components into the electrolyte system to tailor specific targeted properties of the electrolyte without changing the bulk properties. So called "additives" can, for example, generate desired electrode/electrolyte interphase, which can reduce chemical/electrochemical side reactions. In addition, electrolyte properties such as electrochemical stability, ionic conductivity and thermal stability can also be modified. Due to the considerably reduced amount of only a few percent, the use of additives within the electrolyte seems to be the most beneficial, economical and effective method to improve the overall battery performance. In order to identify the most beneficial synergistic effects of electrolyte components such as solvents, salt and additives, E-Lyte Innovations uses a sophisticated High Throughput Screening (HTS) approach. Here, we report on the stabilization of the electrode/electrolyte interface in a graphite/SiOx||NMC622 system using efficient film-forming electrolyte additives aiming to increase the specific discharge capacity, Coulombic efficiency and capacity retention. Furthermore, the effect of tailoring electrolyte specifications to increase the electrochemical performance at low temperatures is presented.