Effect of Fluence and Multi-Pass on Groove Morphology and Process Efficiency of Laser Structuring for 3D Electrodes of Lithium-Ion Batteries

Lithium-ion batteries (LIBs) are widely used as energy storage systems. With the growing interest in electric vehicles, battery performance related to traveling distance has become more important. Therefore, there are various studies going on to achieve high-power and high-energy batteries. Laser structuring of electrodes involves a groove being produced on electrodes by a laser. This technique was used to show that battery performance can be enhanced due to improving Li-ion diffusion. However, there is a lack of studies about the morphological variation of grooves and process efficiency in laser parameters in the laser structuring of electrodes. In this study, the LiFePO4 cathode is structured by a nanosecond laser to analyze the morphological variation of grooves and process efficiency depending on laser fluence and the number of passes. First, the various morphologies of grooves are formed by a combination of fluences and the number of passes. At a fluence of 0.86 J/cm2 and three passes, the maximum aspect ratio of 1.58 is achieved and the surface area of structured electrodes is greater than that of unstructured electrodes. Secondly, three ablation phenomena observed after laser structuring are classified according to laser parameters through SEM images and EDX analysis. Finally, we analyze the amount of active material removal and process efficiency during laser structuring. In conclusion, applying low fluence and multi-pass is assumed to be advantageous for laser structuring of electrodes.

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Characterization and Laser Structuring of Aqueous Processed Li(Ni0.6Mn0.2Co0.2)O2 Thick-Film Cathodes for Lithium-Ion Batteries

Nanomaterials ◽

10.3390/nano11071840 ◽

2021 ◽

Vol 11 (7) ◽

pp. 1840

Author(s):

Penghui Zhu ◽

Jiahao Han ◽

Wilhelm Pfleging

Keyword(s):

Acetic Acid ◽

Lithium Ion Batteries ◽

Thick Film ◽

Active Material ◽

Rate Capability ◽

Lithium Ion ◽

Ph Values ◽

Laser Structuring ◽

Methyl Pyrrolidone ◽

High Processing

Lithium-ion batteries have led the revolution in portable electronic devices and electrical vehicles due to their high gravimetric energy density. In particular, layered cathode material Li(Ni0.6Mn0.2Co0.2)O2 (NMC 622) can deliver high specific capacities of about 180 mAh/g. However, traditional cathode manufacturing involves high processing costs and environmental issues due to the use of organic binder polyvinylidenfluoride (PVDF) and highly toxic solvent N-methyl-pyrrolidone (NMP). In order to overcome these drawbacks, aqueous processing of thick-film NMC 622 cathodes was studied using carboxymethyl cellulose and fluorine acrylic hybrid latex as binders. Acetic acid was added during the mixing process to obtain slurries with pH values varying from 7.4 to 12.1. The electrode films could be produced with high homogeneity using slurries with pH values smaller than 10. Cyclic voltammetry measurements showed that the addition of acetic acid did not affect the redox reaction of active material during charging and discharging. Rate capability tests revealed that the specific capacities with higher slurry pH values were increased at C-rates above C/5. Cells with laser structured thick-film electrodes showed an increase in capacity by 40 mAh/g in comparison to cells with unstructured electrodes.

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Ultrafast laser structuring of Li(Ni0.6Mn0.2Co0.2)O2 cathodes for high energy and high power lithium-ion batteries

Laser-based Micro- and Nanoprocessing XV ◽

10.1117/12.2577569 ◽

2021 ◽

Author(s):

Penghui Zhu ◽

Alexandra Meyer ◽

Wilhelm Pfleging

Keyword(s):

Lithium Ion Batteries ◽

High Power ◽

Lithium Ion ◽

High Energy ◽

Ultrafast Laser ◽

Laser Structuring

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Research on Electrode Structuring for Enhanced Battery Performance

10.21203/rs.3.rs-97419/v1 ◽

2020 ◽

Author(s):

Dongkyoung Lee

Keyword(s):

Aspect Ratio ◽

Alternative Energy ◽

Removal Rate ◽

Active Material ◽

High Energy ◽

High Energy Density ◽

Energy Sources ◽

Nanosecond Laser ◽

Alternative Energy Sources ◽

Laser Structuring

Abstract Currently, alternative energy sources are attracting attention owing to environmental pollution and the depletion of fossil fuels. Lithium-ion batteries have a light weight, high energy density, high power density, and long cycle life, making them attractive alternative energy sources. Numerous studies have been conducted on high-performance batteries. However, most studies have focused on improving active material characteristics. Thus, there is a lack of research on battery performance enhancement through the improvement of the battery manufacturing process. In this study, we performed electrode structuring using a nanosecond laser in the power range of 1 W to 19 W (2 W intervals). The geometric changes after laser structuring were observed using a scanning electron microscope, and the electrode geometries were classified and measured in terms of ablation width and depth. The aspect ratio, removal amount, and removal rate of the active material were analyzed after laser structuring. A maximum aspect ratio of 0.77 was achieved. Additionally, the removal amount and removal rate of the active material increased with the increase in laser power. Therefore, we concluded that electrode geometry can be controlled using a nanosecond laser.

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Lithium Plating Detection Methods in Lithium-ion Batteries

10.1149/osf.io/bj9gr ◽

2020 ◽

Author(s):

Umamaheswari Janakiraman ◽

Taylor R. Garrick ◽

Mary E Fortier

Keyword(s):

Lithium Ion Batteries ◽

Low Cost ◽

Active Material ◽

Lithium Ion ◽

High Energy ◽

Test Methods ◽

High Energy Density ◽

Detection Methods ◽

Anode Surface ◽

Long Cycle Life

Lithium-ion batteries (LiB) offer a low-cost, long cycle-life, and high energy density solution to the automotive industry. There is a growing need of fast charging batteries for commercial applications. However, under certain conditions such as high currents and/or low temperatures, the chance for Lithium (Li) plating increases. The main reason behind plating is the slow solid-state diffusion of Li ions inside the active material. If the anode surface potential falls below 0 V versus Li/Li+, the formation of metallic Li is thermodynamically feasible. Therefore, the determination of an accurate Li plating curve is crucial in estimating the boundary conditions for battery operation without compromising life and safety. There are various electrochemical and analytical methods that are employed in evaluating the Li plating boundary of an LiB. The present paper reviews the common test methods and analysis methods that are currently utilized in Li plating determination. An overview of existing methods, their advantages and limitations are provided in detail.

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Ultra-high-energy lithium-ion batteries enabled by aligned structured thick electrode design

Rare Metals ◽

10.1007/s12598-021-01785-2 ◽

2021 ◽

Author(s):

Chao-Chao Zhou ◽

Zhi Su ◽

Xin-Lei Gao ◽

Rui Cao ◽

Shi-Chun Yang ◽

...

Keyword(s):

Lithium Ion Batteries ◽

Lithium Ion ◽

High Energy ◽

Electrode Design ◽

Ultra High Energy ◽

Thick Electrode

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Boosting Cycling Stability of Ni-rich Layered Oxide Cathode by Dry Coating of Ultrastable Li3V2(PO4)3 Nanoparticles

Nanoscale ◽

10.1039/d0nr08305d ◽

2021 ◽

Author(s):

Dongdong Wang ◽

Qizhang Yan ◽

Mingqian Li ◽

Hongpeng Gao ◽

Jianhua Tian ◽

...

Keyword(s):

Lithium Ion Batteries ◽

Cathode Materials ◽

Lithium Ion ◽

High Energy ◽

Cycling Stability ◽

Next Generation ◽

Layered Oxides ◽

Dry Coating ◽

Layered Oxide ◽

Oxide Cathode

Nickel (Ni)-rich layered oxides such as LiNi0.6Co0.2Mn0.2O2 (NCM622) represent one of the most promising candidates for the next-generation high-energy lithium-ion batteries (LIBs). However, the pristine Ni-rich cathode materials usually suffer...

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