Understanding Battery Interfaces by Combined Characterization and Simulation Approaches: Challenges and Perspectives

Abstract

Driven by the continuous search for improving performances, understanding the phenomena at the electrode/electrolyte interfaces has become an overriding factor for the success of sustainable and efficient battery technologies for mobile and stationary applications. Toward this goal, rapid advances have been made regarding simulations/modeling techniques and characterization approaches, including high‐throughput electrochemical measurements coupled with spectroscopies. Focusing on Li‐ion batteries, current developments are analyzed in the field as well as future challenges in order to gain a full description of interfacial processes across multiple length/timescales; from charge transfer to migration/diffusion properties and interphases formation, up to and including their stability over the entire battery lifetime. For such complex and interrelated phenomena, developing a unified workflow intimately combining the ensemble of these techniques will be critical to unlocking their full investigative potential. For this paradigm shift in battery design to become reality, it necessitates the implementation of research standards and protocols, underlining the importance of a concerted approach across the community. With this in mind, major collaborative initiatives gathering complementary strengths and skills will be fundamental if societal and environmental imperatives in this domain are to be met.

A Roadmap for Transforming Research to Invent the Batteries of the Future Designed within the European Large Scale Research Initiative BATTERY 2030+

“…Their structural properties depend in a highly complex and elusive manner on the specific characteristics of the composition of the electrolyte, the structures of the electrode materials, and the external conditions. Understanding, controlling, and designing the function of interfaces and interphases [ 5 ] is therefore key for the development of ultra‐performing, smart, and sustainable batteries.…”

“…This paper summarizes the roadmap developed by the always BATTERY 2030+ consortium and is complemented by a number of articles in this special issue, including also one paper regarding the state‐of‐the‐art. [ 2–11 ]…”

Accelerating Battery Characterization Using Neutron and Synchrotron Techniques: Toward a Multi‐Modal and Multi‐Scale Standardized Experimental Workflow

“…An overview of surface/interface reactions and relevant characterization techniques can be found in ref. [ 7 ] . 2)Reversible (de)lithiation of electrode materials gives rise to a redox reaction of the electrode material, driven by the ready tendency for Li to donate its 2s electron (small electronegativity) to the neighboring environment. Either the Fermi level in the itinerant electron band (e.g., for graphite electrodes) or a transition metal provides the redox couple, which determines the energy and thus the potential of the electrode in question.…”

“…Accordingly, techniques such as neutron reflectometry, X‐rays reflectivity, and XPS cover length scales that cross the boundary between interface and bulk. These specific techniques are covered in a parallel review on interface processes [ 7 ] and therefore will not be discussed here.…”

“…We expressly spotlight bulk‐type techniques since a parallel paper focuses on surface and interface characterizations. [ 7 ] We address the types of bulk processes involved and their relation to battery electrochemical performance, the progress made in X‐ray and neutron techniques for bulk characterization, and the need for standardization and multi‐method approaches coupled with operando / in situ electrochemical cell development. Also, we introduce future automated, standardized, experimental workflows, incorporating multi‐probe characterization, real‐time feed‐back loops with numerical modeling, machine/deep learning (ML/DL) and artificial intelligence (AI), and correlative data analysis.…”