A new approach for rapid electrolyte wetting in tape cast electrodes for lithium-ion batteries

Pfleging, Wilhelm; Pröll, J.

doi:10.1039/c4ta02353f

Cited by 132 publications

(126 citation statements)

References 34 publications

Supporting

Mentioning

124

Contrasting

Order By: Relevance

“…37,39,40 In that regard, we investigated the effects of wettability induced by changing the viscosity of the electrolyte. First, in order to confirm the wettability of between the electrolytes on the pressed MWCNT-S electrode, we measured the contact angles.…”

Section: Resultsmentioning

confidence: 99%

Controlling the Wettability between Freestanding Electrode and Electrolyte for High Energy Density Lithium-Sulfur Batteries

Hwang

Kim

Sun

2017

J. Electrochem. Soc.

View full text Add to dashboard Cite

The present study demonstrates how to improve the electrochemical performance and energy density of lithium-sulfur batteries based on controlling the wettability between the freestanding electrode and the electrolyte. First, to improve the volumetric energy density, we reduced the thickness of freestanding electrode by the applying pressure. Second, in order to improve electrolyte conductivity and wettability for pressed freestanding electrode, we reduced the viscosity of electrolyte solution by reducing the LiTFSI salt concentration. Through these controls, the Li-S cell is constructed from a pressed freestanding carbon nanotube-sulfur cathode, 0.5 M LiTFSI in DME/DOL with 0.4 M LiNO 3 as a low-viscosity electrolyte (0.72 cP), and Li-metal foil as an anode. As a result, we can obtain a high discharge capacity of 1,400 mAh g −1 at 0.1 C and excellent cycle retention of 95% after 80 cycles at 0.5 C in coin-type cell. In addition, scale-up (3 by 5 cm) pouch-type Li-S cell delivers a high discharge capacity of 500 mAh at 0.1 C with high gravimetric (954. In order to mitigate the global environmental issues associated with the use of fossil fuels and the resulting greenhouse gas emissions, clean and sustainable energy production and storage technologies are urgently needed.1,2 In this context, lithium-ion battery (LIB) technology has progressed considerably, with continuing applications in potential energy storage devices. However, current LIBs have limited applications in electric vehicles, hybrid electric vehicles, and power grids, owing to their low theoretical energy densities.3-6 Therefore, for mid-to-large-scale applications, it is imperative that we explore alternatives that offer the possibility of going beyond the limits of the intercalation chemistry of current Li-ion technology. 7The lithium-sulfur (Li-S) battery has emerged as a next-generation rechargeable battery, owing to the involvement of multiple electrons during the redox reactions between Li and S, which provides high theoretical energy density (2,600 Wh kg −1 ) and specific capacity (1,675 mAh g −1 ). 8,9 In addition, due to abundance of elemental sulfur and its environmental compatibility, Li-S battery has been considered the much more attractive power sources. Despite these advantages, current Li-S battery have various disadvantages such as poor electrical conductivities of sulfur and Li 2 S, 10,11 undesirable shuttle reactions, 12,13 and huge volume changes of sulfur (∼80%) upon cycling, 14 which have severely delayed the commercialization of Li-S batteries.In order to overcome these problems, various strategies have been implemented to improve the design of both the electrode and the electrolytes materials.15-23 A freestanding electrode is one of attractive choice as the cathode for a Li-S battery, because it is fabricated without a binder or any powdery conductive materials, thereby allowing higher percentages of active material (S 8 ) in the cathode. 24 In addition, by taking advantage of their porous structure, the use of freestanding ele...

show abstract

Section: Resultsmentioning

confidence: 99%

Controlling the Wettability between Freestanding Electrode and Electrolyte for High Energy Density Lithium-Sulfur Batteries

Hwang

Kim

Sun

2017

J. Electrochem. Soc.

View full text Add to dashboard Cite

show abstract

“…We find that an appropriate structure design and complete removal of the electrode material from the ablation zone delivers the most efficient capillary transport. 11 Nanosecond laser ablation, however, is not appropriate for all 11 Li: Lithium. C: Carbon.…”

Section: Figure 1 Scanning Electron Microscope Images Of Laser-genermentioning

confidence: 99%

Laser structuring for improved battery performance

Pfleging¹,

Mangang²,

Zheng³

et al. 2016

SPIE Newsroom

Self Cite

View full text Add to dashboard Cite

New material architectures and electrode surface topographies are used in high-power batteries to improve battery lifetime and cell stability.Within the last two decades, lithium-ion batteries (LIBs) have emerged as the power source of choice in the high-performance rechargeable battery market. 1, 2 LIBs are high-capacity batteries that are able to store electricity converted from green energy sources (e.g., solar and wind power), and they can act as energy sources in pollution-free electric vehicles. Nevertheless, there are several drawbacks to state-of-the-art LIBs, including high production costs, short battery lifetimes, safety issues, and time-consuming charging periods. The main issue in cell production is the electrolyte wetting of LIBs, which is realized through time-and cost-consuming vacuum and storage processes at elevated temperatures. Insufficient wetting of electrodes results in a production failure rate, accompanied by a reduced cell capacity and cell lifetime.The development of 3D electrode architectures in LIBs is a relatively new approach for overcoming the problems related to battery performance (e.g., power losses or high interelectrode ohmic resistances 3 ) and mechanical degradation 4 during battery operation. 3D batteries can be used to achieve large areal energy capacities, while simultaneously maintaining high power densities. A common approach is 3D structuring of the electrode substrate (the 'current collector') before deposition of the thin-film electrode. Unfortunately, this method is in a very early stage of development for model electrodes in thin-film microbatteries. Furthermore, it is generally not feasible for up-scaling to thick-film composite electrodes or for large electrode footprint areas.At the Karlsruhe Institute of Technology, we have thus developed a new technical approach for the generation of 3D electrode designs that can be applied to all types of LIBs (i.e., thin-film batteries, as well as high-energy and high-power LIBs). 5 In this approach, for the first time, we have applied laser-assisted processing to the active electrode material itself. For this Figure 1. Scanning electron microscope images of laser-generated microstructures in composite electrode materials. (a) Self-organized microstructures (produced with the use of an excimer laser) and (b) micro-pillars obtained from direct laser structuring with an ultrafast (femtosecond) laser.purpose, we established different types of laser processing for increasing the active surface area, 6-8 i.e., 'laser-assisted selforganizing structuring' and 'direct structuring' of electrodes. The first of these processes can be applied to thin films and thickfilm electrodes that have small electrode footprint areas (coin cells). The second process is suitable for small and large electrode footprint areas (pouch cells).We used excimer laser ablation at a wavelength of 248nm to produce self-organized surface structures-see Figure 1(a)-on lithium cobalt oxide and lithium nickel manganese cobalt oxide (NMC) thick-and thin-film elect...

show abstract

“…Therefore, laser direct structuring of the active electrode material has been developed for thin film electrodes made of LiCoO 2 , LiMn 2 O 4 , SnO 2 or fluorine doped SnO 2 (FTO) [14][15][16][17][18][19][20][21][22][23]. In a very recent approach, it was shown that laser-structuring can be applied for LiCoO 2 , LiMn 2 O 4 , LiNi 1/3 Mn 1/3 Co 1/3 O 2 and silicon composite electrodes with film thicknesses of 50 to 100 µm [24][25][26][27][28].…”

Section: Introductionmentioning

confidence: 99%

Surface micro-structuring of intercalation cathode materials for lithium-ion batteries: a study of laser-assisted cone formation

et al. 2015

View full text Add to dashboard Cite

Strong efforts are currently undertaken in order to further improve the electrochemical performance of high energy lithium-ion batteries containing thick composite electrode materials. The properties of these electrode materials such as active surface area, film thickness, and film porosity strongly impact the cell life-time and cycling stability. A rather new approach is to generate hierarchical architectures into cathode materials by laser direct ablation as well as by laserassisted formation of self-organized structures. It could be shown that appropriate surface structures can lead to a significant improvement of lithium-ion diffusion kinetics leading to higher specific capacities at high charging and discharging currents. In this paper, the formation of self-organized conical structures in intercalation materials such as LiCoO 2 and LiNi 1/3 Mn 1/3 Co 1/3 O 2 is investigated in detail. For this purpose, the cathode materials are exposed to excimer laser radiation with wavelengths of 248 nm and 193 nm leading to cone structures with outer dimensions in the micrometer range. The process of cone formation is investigated using laser ablation inductively coupled plasma mass spectrometry and laser-induced breakdown spectroscopy (LIBS). Cone formation can be initiated for laser fluences up to 3 J/cm 2 while selective removal of lithium was observed to be one of the key issues for starting the cone formation process. It could be shown that material re-deposition supports the cone-growth process leading to a low loss of active material. Besides the cone formation process, laser-induced chemical surface modification will be analysed by LIBS.

show abstract

A new approach for rapid electrolyte wetting in tape cast electrodes for lithium-ion batteries

Abstract: A dramatic acceleration of electrode wetting with liquid electrolyte was achieved by laser-assisted formation of capillary microstructures in cathode materials.

Cited by 132 publications

References 34 publications

Controlling the Wettability between Freestanding Electrode and Electrolyte for High Energy Density Lithium-Sulfur Batteries

Controlling the Wettability between Freestanding Electrode and Electrolyte for High Energy Density Lithium-Sulfur Batteries

Laser structuring for improved battery performance

Surface micro-structuring of intercalation cathode materials for lithium-ion batteries: a study of laser-assisted cone formation

Contact Info

Product

Resources

About