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Abstract Lithium-ion batteries (LIBs) have solidified their position as primary energy storage solutions for applications ranging from portable electronics to electric vehicles. As power-intensive applications expand, achieving fast charging/discharging performance is increasingly critical for high-energy-density batteries. However, the increased thickness of electrodes in LIBs presents significant challenges for charge (Li+and electron) transfer kinetics, as longer charge migration distances hinder fast charging and discharging performance. Enormous efforts have been made to summarize advancements in materials chemistry—optimizing ionic pathways and crystal structure—to enhance Li+transfer within the bulk of electrode materials. Yet, materials design and modifications fall short of fully addressing Li+and electron transport limitations in thick electrodes. Despite the significance of potentially offering a solution to these constraints, the strategic engineering of electrode architecture has been rarely discussed. In this mini-review, we highlight recent innovations in electrode structural design for fast-charging applications, examining gradient architectures, low-tortuosity structures, and novel current collector designs. By exploring these advanced approaches and offering perspectives on future developments, we aim to promote further advancements toward achieving high-energy-density, fast-charging LIBs.
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Bioinspired Hierarchical Porous Architecture for Enhanced Kinetics and Mechanical Integrity in Thick Cathode
Abstract Increasing the thickness of the electrodes is considered the primary strategy to elevate battery energy density. However, as the thickness increases, rate performance, cycling performance, and mechanical stability are affected due to the sluggish ion transfer kinetics and compromised structural integrity. Inspired by the natural hierarchical porous structure of trees, electrodes with bioinspired architecture are fabricated to address these challenges. Specifically, electrodes with aligned columns consist of tree‐inspired vertical channels, and hierarchical pores are constructed by screen printing and ice‐templating, imparting enhanced electrochemical and mechanical performance. Employing an aqueous‐based binder, the LiNi0.8Mn0.1Co0.1O2cathode achieves a high areal energy density of 15.1 mWh cm−2at a rate of 1C at mass loading of 26.0 mg cm−2, benefitting from the multiscale pores that elevated charge transfer kinetics in the thick electrode. The electrodes demonstrate capacity retention of 90% at the 100th cycle at a high current density of 5.2 mA cm−2. To understand the mechanisms that promote electrode performance, simplified electro‐chemo‐mechanical models are developed, the drying process and the charge‐discharge process are simulated. The simulation results suggested that the improved performance of the designed electrode benefits from the lower ohmic overpotential and less strain gradient and stress concentration due to the hierarchical porous architecture.
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- Award ID(s):
- 2142290
- PAR ID:
- 10553409
- Publisher / Repository:
- Wiley
- Date Published:
- Journal Name:
- Small
- ISSN:
- 1613-6810
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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- Free Publicly Accessible Full Text
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Accepted Manuscript
- Journal Article:
- https://doi.org/10.1002/smll.202406058
