(338h) Fabrication and Characterization of Organic-Inorganic Composite Electrolytes for Solid-State Batteries

With the rapidly growing demand for rechargeable electronic devices, the future of lithium-ion batteries (LIBs) hinges on their safe operation. Despite recent advancements, current technologies face serious challenges that require immediate attention. At present, LIBs hold the largest share in the global battery market. However, there are numerous reports of battery explosions in electronic devices, such as cell phones and electric vehicles (EVs). These explosions can be attributed to dendrite formation, electrode oxidation, thermal degradation of liquid electrolytes, short circuits of electrodes, and thermal runaway.

To mitigate these safety risks, a new generation of lithium batteries, called all-solid-state lithium metal batteries, has been introduced. The solid-state nature and absence of organic solvents in this new design significantly reduce the risks of dendrite formation and thermal degradation of electrolytes. Consequently, short circuits of electrodes are expected to no longer be a major concern. Nonetheless, solid electrolytes encounter problems due to their low ionic conductivity, which might impact the overall system's performance.

By implementing organic-inorganic composite electrolytes (OICEs) in the all-solid battery architecture, it is expected that health hazards can be mitigated and long-lasting batteries for cell phones and EVs can be realized. In this study, we address this challenge by incorporating conductive, crystalline, porous, and capacitive fillers and fabricating novel OICEs for all-solid-state lithium metal batteries. These batteries are expected to outperform the current state of the art and potentially address the issues facing solid-state electrolytes.

We employ ion-conducting polymers, carbide, and ionic covalent organic frameworks (iCOFs) as fillers, and then optimize the electrolyte composition to achieve the target ionic conductivity of approximately 10^-5 S/m at room temperature for lithium ions within the matrix. The resulting ion conductors are anticipated to enhance the performance of current lithium metal batteries by facilitating ionic transport and reducing safety hazards.