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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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Block‐Copolymer‐Architected Materials in Electrochemical Energy Storage
The multiscale architecture of electrochemical energy storage (EES) materials critically impacts device performance, including energy, power, and durability. The pore space of nano‐ to macrostructured electrodes determines mass transport within the electrolyte and defines the effective energy density. The dimensions of the active charge‐storing materials can increase stability during cycling by accommodating strains from electrochemical–mechanical coupling while also defining surface area that increases capacitive charge storage, decreases charge‐transfer resistance, but also leads to low efficiency and degradation from interfacial reactions. Thus, elucidating and developing a fundamental understanding of these correlations requires materials with precisely tunable nanoscale architectures. Herein, approaches that take advantage of the nanoscale control offered by block copolymer (BCP) self‐assembly are reviewed and insights gained from associated nanoscale phenomena observed in EES are highlighted. Systematic studies that use custom‐tailored BCPs to reveal fundamental nanostructure–property–performance relationships are emphasized. Importantly, most reports of nanostructured materials utilize low loadings and thin electrodes and results represent mass transfer limitations at the particle scale. However, as cell‐level performance involves mass transport over 10–100s of micrometers, recently emerging BCP‐based processes are further highlighted, leading to hierarchical meso/macroporous materials needed for creating multiscale structure–performance relationships and next‐generation energy storage material architectures.
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- PAR ID:
- 10482249
- Publisher / Repository:
- Wiley Blackwell (John Wiley & Sons)
- Date Published:
- Journal Name:
- Small Science
- Volume:
- 3
- Issue:
- 12
- ISSN:
- 2688-4046
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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