Learning & Networking: Solid-State Batteries & Frontier Battery Materials

Solid-state and semi-solid-state batteries (SSB) are considered as one of the most promising next generation batteries for several emerging applications, with a special focus on electromobility. Despite very intensive academic research on materials and components for SSB, their further scale up and integration in SSB prototypes is not yet considered on their design, slowing down their fully deployment in the marketplace. In this context, CIDETEC Energy Storage is focused on the development of three transversal SSB technologies: (i) lithium metal, (ii) lithium-ion, and (iii) anode-free, pursuing a holistic approach to up-scale cells at relevant sizes to industry. This presentation will cover CIDETEC´s vision on SSB R&D and discuss key findings of our development.

Current state-of-the-art LIBs based on intercalation chemistry are nearing the maximum energy density limit (≤ 300 Wh/kg), whereas solid-state LIBs with thicker electrodes and high areal capacity (> 6 mAh/cm2) under the same electrochemistry might attain ≥ 450 Wh/kg. This value could go even higher to ~ 600 Wh/kg with the incorporation of an anode with a high Si content or lithium-metal as an anode. In addition, solid electrolytes are relatively stable up to 5 V, making them good candidates for integration with high voltage cathodes, allowing for high energy density; while liquid electrolytes deteriorate at higher potentials, restricting their usage with high-voltage cathodes. Considering safety is the most important factor, batteries with thermally robust solid-state electrolytes could be safer than those with flammable liquid electrolytes. Furthermore, prolonged cycle life is also possible with solid electrolyte because the parasitic reaction of liquid electrolyte, the primary cause of capacity loss, is minimized. In this talk, I would discuss on advantages and some challenges in the development of solid electrolytes with high Li-ion conductivity and enhanced interfacial stability.

Solid State Batteries (SSBs) are viewed as a promising route to increase the energy density of batteries for EV and consumer electronic applications. To achieve this will require ultra-thin lithium metal, possibly transitioning to lithium electrodeposition where the battery accommodates a lithium metal anode or an “anode less” design. Lithium metal is highly reactive and flammable making its use in common goods an increased challenge. Its electrochemical deposition is poorly controlled and often leads to the growth of lithium dendrites creating optimal short-circuiting pathways, this phenomenon being enhanced under fast charge and discharge cycles.
Over the years, traditional lithium-ion batteries have experienced a large variety of failure scenarios which led the community to develop tools to assess the safety of new chemistry and designs prior their release to the market. A similar approach should be used to understand the unique failure events of SSBs and the impact they could have on the end user. In this talk, we will review some of the tools available to the community to do so.

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