In line with efforts toward shifting reliance on fossil fuels to renewable energy, the large-scale realization of electrochemical energy storage has been a major research focus. In particular, rechargeable batteries offer remarkable performance, tunable parameters, and good scalability at a continuously decreasing cost.
Although lithium-ion batteries (LIBs) have reigned supreme in applications such as portable electronics, there is the hope that other battery concepts—including lithium-metal-based all-solid-state batteries (ASSBs), lithium/sulfur batteries (LSBs), quasi-solid-state lithium/sulfur batteries (QSS-LSBs), magnesium/sulfur batteries (MSBs), or dual-ion batteries (DIBs)—could outperform LIBs.
However, there is an underlying problem in the research community in the way battery performance parameters are reported. Novel battery concepts often promise a very high theoretical energy per mass or volume, but these values exclude numerous relevant parameters for practical battery cells. The practical mass utilization of the active material, practically achieved discharge voltages, and especially the required amount of inactive materials on a stack level varies substantially between different cell chemistries.
As a result, the use of theoretical energy or capacity values (mostly only at the material level) commonly quoted for emerging battery chemistries might drastically overestimate the realistic potential of these systems in comparison to LIBs.
To address this issue, researchers from MEET Battery Research Center at the University of Münster and Helmholtz-Institute Münster have identified which cell components are the most critical for achieving higher energy values by comprehensively evaluating the practical specific energies and energy densities for six selected battery technologies.
By providing a tool to calculate the energy values of the six different battery technologies with different assumptions, this study provides a more transparent, realistic assessment and comparison of current and evolving battery technologies.
Dr. Richard Schmuch, one of the study’s researchers who currently works on the project BenchBatt, which is dedicated to the evaluation of current and possible next-generation batteries, states, “In times of rapid technological diversification in the field of batteries, where often individual advantages of an emerging technology are highlighted (e.g., charge density at the material level), comparative studies focusing on a comprehensive set of parameters that influence the practical energy contents become increasingly important as guideposts to evaluate the true potential of emerging battery technologies.”