Challenges, laser processing and electrochemical characteristics on application of ultra-thick electrode for high-energy lithium-ion battery
https://www.sciencedirect.com/science/article/pii/S0378775320312477
Junsu Park , Chanyoung Jeon , Wonhee Kim , Sung-Jae Bong , Sungho Jeong , Hyeong-Jin Kim
Lithium-ion batteries with ultra-thick electrodes are difficult to manufacture due to high internal resistance. This study reports on the effects of laser structuring of ultra-thick electrodes for high-energy batteries. Lithium cobalt oxide anodes (700 μm) and graphite cathodes (650 μm) are prepared with an areal discharge capacity of 25 mAh cm−2. After laser structuring, the surface morphology and chemical properties of the electrodes are investigated, and the internal resistance and diffusion characteristics are analyzed using electrochemical impedance spectroscopy. Laser structuring reduces twisting, decreases electron and ion resistance, and enhances diffusion characteristics. The rate capability and areal discharge capacity of the laser-structured cells increase fivefold compared to unstructured cells under 0.1 C conditions. Therefore, laser structuring presents a viable approach for high-energy batteries.
•Title
Battery recycling – Exploitation of laser technologies for dismantling and recycling processes
•Authors
Max Rettenmeier, Mauritz Möller, Oliver Bocksrocker, Vinayakrajr Salvarrajan, Christoph Neugebauer
•
•Keywords
Recycling
cutting processes
ablating processes
dismantling
battery pack
•
•Journal : Lasers in Manufacturing Conference 2023 (LiM 2023)
The ramp-up of new production infrastructure to manufacture lithium-ion batteries for battery electric vehicles is moving ahead at a rapid pace. These enormous quantities of vehicle batteries must be recycled in a fast loop due to the increasing shortage of critical raw materials. Laser technologies offer the possibility to perform many of the necessary process steps of dismantling and recycling. In this paper, an application overview and analysis of laser technologies in the field of cutting and ablating processes will be presented. The cutting processes are primarily focused on the dismantling of metal and metal-plastic components of battery packs. Furthermore, in the ablative processes, the ablation of active material of the battery electrode foil using ns-pulsed lasers is investigated. Within the scope of this application, the elaboration of lasertechnological parameter fields will be pursued in particular
•Title
Sequential Separation of Battery Electrode Materials and Metal Foils in Aqueous Media
•Yaocai Bai, Lu Yu, and Ilias Belharouak
•Keywords
-Lithium-ion batteries
-Direct recycling
-Surfactant
-Battery recycling
-Anode
-Cathode
•Journal : Journal of Power Sources
To recycle high-value lithium-ion battery components, it is imperative to efficiently separate electrode materials from current collector foils and to separate cathodes from anodes. This study investigates the delamination behaviors of cathodes and anodes from their respective current collectors in aqueous media. Whereas anode films can easily detach from copper foils in water, the delamination of cathode films does not exhibit the same behavior in water; instead, the cation exchange reaction results in lithium leaching and aluminum corrosion in the presence of water. A buffer solution with surfactant additives has been designed to prevent aluminum corrosion and to improve solution wetting behavior, thereby facilitating cathode delamination. The delamination difference enables the sequential recovery of electrode materials and metal foils at different separation stages, simplifying the traditionally intricate processes within a one-pot recovery system. The recovered materials retain their crystal structure and morphology, and there are no signs of aluminum corrosion or residues on the metal foils. The sequential separation technique achieves nearly 100% separation efficiency for electrode materials from metal foils and over 98% separation efficiency for cathode and anode materials.
•Title :
Laser structured Cu foil for high-performance lithium-ion battery
anodes
•Author :
Ningxin Zhang, Yijing Zheng, Atanaska Trifonova, Wilhelm Pfleging
•Keyword :
Ultrafast laser ablation (초고속 레이저 어블레이션)
Adhesive force (접착력)
Anode films (음극 필름)
Orientation of graphite particles (흑연 입자 배열)
Li⁺ diffusion (리튬 이온 확산)
•Journal : Journal of Applied Electrochemistry
To improve interface adhesion between anode film and Cu foil, ultrafast laser structuring was implemented to construct dot patterns with a variety of periodic spacing (25, 50, and 75 µm) on Cu foil. The microstructure and electrochemical performance of anode films coated on those structured Cu foils were characterized. It was shown that adhesive force of the electrodes increased as periodic distance between the dots on the Cu foil decreased. Comparison of XRD patterns of the wet slurries with the dried anode films showed that after drying in the case of 50 µm period dot structured Cu foils the most graphite particles were aligned with the c-axis, vertical to the Cu foil surface. EIS, CV, and rate capability measurements confirmed that the anode film on the 50 µm dot period Cu foil had the lowest impedance, strongest lithiation and de-lithiation peaks, and highest discharge capacity. The cycling test carried out under C/2 rate confirmed that the cells with the 50 µm dot interval Cu foil showed the highest capacity retention. We inferred that this was due to the relatively shorter diffusive path in the anode due to vertical orientation of more graphite particles against the laser structured Cu foil.
• Title
Interface characteristics of peeling-off damages of laser coatings
• Authors
Yun Cui, Kui Yi, Guohang Hu, Jianda Shao
• Keywords
ü Optical coatings
ü Interface characteristics
ü Laser irradiation
ü Peeling-off damage
• Journal : Applied Surface Science, Volume 290, pp. 71–79 (2014)
Multilayer coating stacks composed of HfO₂/SiO₂ and Ta₂O₅/SiO₂ were prepared using electron beam evaporation and dual ion beam sputtering, respectively. In this study, the interface characteristics of peeling-off damage were investigated after irradiation with a 1064 nm laser. Cross-sectional analysis of the damaged regions showed that peeling-off damage consistently occurred at interfaces where the low-refractive-index SiO₂ layer was deposited on the high-refractive-index HfO₂ or Ta₂O₅ layer. The results indicated that interface microstructure was not the primary factor affecting peeling-off damage. Instead, incomplete silicon oxides (SiOₓ) and trace ions, including Na, K, and Li, accumulated near the interfaces and formed nanoscale micro-defect layers. These defect layers may reduce interfacial adhesion and absorb laser energy, leading to plasma formation and subsequent stripping damage during laser irradiation.
•Title :
이차전지 음극재 탄소 소재 재활용에 대한 연구
•Author :
한경재, 김유진, 윤성진, 강유진, 장민혁, 조형근, 조혜령, 서동진, 박주일
•Keyword :
Graphite (흑연)
Separation & Purification (분리 및 정제)
Regeneration (재생 공정)
Anode material (음극재)
Recycling & Economic effect (재활용 및 경제적 효과)
•Journal : Journal of the Korea Organic Resources Recycling Association
Lithium-ion batteries have greatly expanded along with the mobile phone market, and as the electric vehicle business is activated in earnest, they will attract many people's attention even afterwards. Until now, many people have attracted attention to the recovery of valuable metals inside lithium-ion batteries, but graphite, which is mainly used as an anode material, is also worth recycling. Therefore, in order to recover graphite with high purity and valuable metals, graphite that can be used as an anode material of a secondary battery may be generated again through a regeneration process of purifying and separating graphite from a waste lithium-ion battery and recovering electrical characteristics of graphite. This paper describes the process of converting waste graphite into regenerated graphite and the environmental and economic effects of regenerated graphite.
• Title
Analysis of kerf quality on ultrafast laser cutting of anode material for lithium-ion battery
• Authors
Yi Zhang, Jianxiang Li, Rukun Yang, Tongwei Liu, Yiguo Yan
• Keywords
Ultrafast laser cutting
Anode material
HAZ
Delamination width
• Journal : Optics and Lasers in Engineering, Volume 118, pp. 14–21 (2019)
The cutting quality of electrode materials is an important factor affecting the performance and safety of lithium-ion batteries. In this paper, ultrafast laser cutting was applied to an anode material composed of graphite layers coated on both sides of a copper foil. The effects of laser power and pulse width on the kerf depth, heat-affected zone (HAZ), and delamination width were investigated. The results showed that the kerf depth varied as a piecewise function of laser power and that the cutting process was mainly influenced by the copper foil due to its low absorptivity and high thermal conductivity. Raman analysis revealed that the ordered graphite structure was partially damaged in the color-changed region near the kerf edge. The HAZ and delamination width increased with increasing laser power and pulse width because of heat accumulation and plasma thermal radiation. Furthermore, multi-scan cutting at low laser power and high scanning speed significantly reduced the thermal effect and completely eliminated delamination, improving the cutting quality of the anode material.