From Fundamental Understanding to Engineering Design of High‐Performance Thick Electrodes for Scalable Energy‐Storage Systems

TLDR

The growing demand for renewable energy drives the need for batteries with higher energy and power output, and thick electrode designs are promising because they reduce inactive material ratios, yet their impact on cell‑level energy densities and the energy‑power trade‑off remains underexplored. This study aims to quantify how electrode thickness, active material fraction, and porosity jointly influence cell‑level energy and power densities in Li–NMC622 and Li–S batteries, targeting 500 Wh kg⁻¹/800 Wh L⁻¹ and outlining strategies to simultaneously boost energy and power output. The authors perform a realistic assessment using state‑of‑the‑art lithium‑battery models, evaluating the combined effects of electrode thickness, active material fraction, and porosity on energy and power densities in Li–NMC622 and Li–S cells.

Abstract

Abstract The ever‐growing needs for renewable energy demand the pursuit of batteries with higher energy/power output. A thick electrode design is considered as a promising solution for high‐energy batteries due to the minimized inactive material ratio at the device level. Most of the current research focuses on pushing the electrode thickness to a maximum limit; however, very few of them thoroughly analyze the effect of electrode thickness on cell‐level energy densities as well as the balance between energy and power density. Here, a realistic assessment of the combined effect of electrode thickness with other key design parameters is provided, such as active material fraction and electrode porosity, which affect the cell‐level energy/power densities of lithium–LiNi 0.6 Mn 0.2 Co 0.2 O 2 (Li–NMC622) and lithium–sulfur (Li–S) cells as two model battery systems, is provided. Based on the state‐of‐the‐art lithium batteries, key research targets are quantified to achieve 500 Wh kg –1 /800 Wh L –1 cell‐level energy densities and strategies are elaborated to simultaneously enhance energy/power output. Furthermore, the remaining challenges are highlighted toward realizing scalable high‐energy/power energy‐storage systems.