Exploiting the Spinel Structure for Li‐ion Battery Applications: A Tribute to John B. Goodenough

Abstract This review provides a personal account of career‐long efforts, interwoven with the contributions of others, to exploit the [B 2 ]O 4 framework of an A[B 2 ]O 4 spinel structure for lithium‐ion battery applications, where A = Li, and B is one or more metal cations. The narrative starts at the Council for Scientific and Industrial Research (CSIR) in South Africa in the mid‐1970s when, in response to the Middle East oil crisis, worldwide efforts were turned to develop high‐temperature sodium and lithium batteries to power electric vehicles. In 1981, results in CSIR's program on a high‐temperature lithium battery led to a collaborative project on room‐temperature lithium cells with Prof. John B. Goodenough at Oxford University, where studies of Fe 3 O 4 , Mn 3 O 4 , and LiMn 2 O 4 cathodes led to the recognition of the broad utility of the [B 2 ]O 4 spinel framework as an anode, cathode, or solid electrolyte for rechargeable lithium cells. This finding has had a profound and lasting impact, influencing further ideas and discoveries at the CSIR, Argonne National Laboratory, and elsewhere. The narrative emphasizes the compositional versatility of the spinel structure and the opportunities to tailor the electrochemical potential and stability of a Li‐ion cell.