Prospective Application, Mechanism, and Deficiency of Lithium Bis(oxalate)Borate as the Electrolyte Additive for Lithium-Batteries

Lithium bis(oxalate)borate (LiBOB) is one of the most common film-forming electrolyte additives used in lithium ion batteries (LIBs), since it can form a dense boron-containing polymer as a solid electrolyte interlayer (or cathode electrolyte interlayer) in order to isolate the electrode material from the electrolyte and prevent side reactions. LiBOB can serve as HF scavenger to maintain the structural integrity of electrodes via avoiding the transition metal dissolution caused by HF attack. LiBOB also can react with LiPF6 to generate lithium difluoro (oxalate)borate (LiDFOB) that can be further used as a clean-up agent for reactive oxygen radicals. This article lists the application of LiBOB in high capacity and high voltage cathode materials, and also reviews the working mechanisms of LiBOB used in these materials to improve the performance of LIBs. Finally, it presents the current shortcomings of LiBOB and strategies to overcome these. This article is expected to provide useful insights for employing LiBOB as a feasible method of dealing with the difficulty of running high capacity LIBs stably under high voltage.

Automated summary

The article introduces the application of LiBOB in lithium ion batteries, which can form a dense boron-containing polymer as a solid electrolyte interlayer to isolate the electrode material from the electrolyte and avoid side reactions. LiBOB can also act as an HF scavenger to maintain the structural integrity of electrodes and react with LiPF6 to generate LiDFOB as a clean-up agent for reactive oxygen radicals. The article summarizes the application and working mechanisms of LiBOB in high capacity and high voltage cathode materials, as well as the current challenges and strategies to overcome them. It provides useful insights for stable operation of high capacity LIBs under high voltage.