Open Access

This dissertation explores the advancements in the design and manufacturing of lithium-ion batteries (LIB), with a focus on metal oxide-based materials and techniques used to enhance their performance. It discusses the processes to boost efficiency and environmental friendliness. The primary goal is to address the challenges of metal oxide electrodes in LIBs, particularly capacity degradation at high charge/discharge rates and expanding their operating voltage range. We are confident in our ability to enhance the characteristics of these electrodes through preparation methods. Our research investigates how different mixing techniques and variables can improve the performance and durability of these electrodes. Furthermore, this thesis describes our efforts to digitize the battery manufacturing process by introducing the DigiBatMat platform, a platform for battery materials and manufacturing processes. DigiBatMat drives advancements in battery technology by optimizing LIBs through data gathering and analysis, highlighting its crucial role in this field. Ultimately, this thesis provides insights into battery electrode engineering and supports initiatives to improve energy storage technologies and advance sustainability efforts.

Materials containing imidazole have been used as promising substances in the fields of life sciences, environmental science, and electrochemistry. In this study, tailored core–shell particles that respond to acidic solutions and fluorine-containing hydrophobic anions were synthesized through starved-feed emulsion polymerization. Imidazole, which responds to proton acids and hydrophobic anions, was incorporated as a functional moiety into the shell of the particles. The soft and viscoelastic matrix was composed of the copolymer, poly((n-butyl acrylate)-co-(1-vinylimidazole)), allowing for control of the hydrodynamic diameter of the core–shell particles due to the balance between hydrophilic and hydrophobic properties. The size comparison of monodisperse particles in the colloid state was investigated using dynamic light scattering (DLS) and transmission electron microscopy (TEM). Changes in the glass transition temperature, depending on the copolymer ratio, were calculated using the Fox equation. The particles were melt-sheared after extrusion to produce viscoelastic opal films, arranging the particles into colloidal crystal stacks showing vivid structural colors. The optical features changed in response to acidic solutions and hydrophobic anions and were examined using in situ ultraviolet–visible (UV–vis) spectroscopy. The degree of hydrophilicity of the film was compared through contact angle measurements. The manufactured smart opal film can be applied as an affordable sensor that exhibits optical color changes in response to acidic pH and hydrophobic anions.

The significant demand for energy storage systems has spurred innovative designs and extensive research on lithium-ion batteries (LIBs). To that end, an in-depth examination of utilized materials and relevant methods in conjunction with comparing electrochemical mechanisms is required. Lithium titanate (LTO) anode materials have received substantial interest in high-performance LIBs for numerous applications. Nevertheless, LTO is limited due to capacity fading at high rates, especially in the extended potential range of 0.01–3.00 V versus Li+/Li, while delivering the theoretical capacity of 293 mAh g−1. This study demonstrates how the performance of the LTO anode can be improved by modifying the manufacturing process. Altering the dry and wet mixing duration and speeds throughout the manufacturing process leads to differences in particle sizes and homogeneity of dispersion and structure. The optimized anode at 5 A g−1 (≈17C) and 10 A g−1 (≈34C) yielded 188 and 153 mAh g−1 and retained 73% and 68% of their initial capacity after 1000 cycles, respectively. The following findings offer valuable information regarding the empirical modifications required during electrode fabrication. Additionally, it sheds light on the potential to produce efficient anodes using commercial LTO powder.

Li–S batteries with an improved cycle life of over 1000 cycles have been achieved using cathodes of sulfur-infiltrated nanoporous carbon with carbonate-based electrolytes. In these cells, a protective cathode–electrolyte interphase (CEI) is formed, leading to solid-state conversion of S to Li2S in the nanopores. This prevents the dissolution of polysulfides and slows capacity fade. However, there is currently little understanding of what limits the capacity and rate performance of these Li–S batteries. Here, we aim to deepen our understanding of the capacity and rate limitation using a variety of structure-sensitive and electrochemical techniques, such as operando small-angle neutron scattering (SANS), operando X-ray diffraction (XRD), electrochemical impedance spectroscopy, and galvanostatic charge/discharge. Operando SANS and XRD data give direct evidence of CEI formation and solid-state sulfur conversion occurring inside the nanopores. Electrochemical measurements using two nanoporous carbons with different pore sizes suggest that charge transfer at the active material interfaces and the specific CEI/active material structure in the nanopores play the dominant role in defining capacity and rate performance. This work helps define strategies to increase the sulfur loading while maximizing sulfur usage, rate performance, and cycle life.

Organic materials have emerged as highly efficient electrodes for electrochemical energy storage, offering sustainable solutions independent from non-renewable resources. In this study, we showcase that mesoscale engineering can dramatically transform the electrochemical features of a molecular organic carboxylic anode. Through a sustainable, energy-efficient and environmentally benign self-assembly strategy, we developed a network of organic nanowires formed during water evaporation directly on the copper current collector, circumventing the need for harmful solvents, typically employed in such processes. The organic nanowire anode delivers high capacity and rate, reaching 1888 mA h g−1 at 0.1 A g−1 and maintaining 508 mA h g−1 at a specific current of 10 A g−1. Moreover, it exhibits superior thermal management during lithiation in comparison to graphite and other organic anodes. Comprehensive electrochemical evaluations and theoretical calculations reveal rapid charge transport mechanisms, with lithium diffusivity rates reaching 5 × 10−9 cm2 s−1, facilitating efficient and rapid interactions with 24 lithium atoms per molecule. Integrated as the negative electrode in a lithium-ion capacitor, paired with a commercially available porous carbon, the cell delivers a specific energy of 156 W h kg−1 at a specific power of 0.34 kW kg−1 and 60.2 W h kg−1 at 19.4 kW kg−1, establishing a benchmark among state-of-the-art systems in the field. These results underscore the critical role of supramolecular organization for optimizing the performance of organic electrode materials for practical and sustainable energy storage technologies.