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Lithium-ion batteries are currently one of the most important energy storage devices for various applications. However, it remains a great challenge to achieve both high energy density and high-power density while reducing the production costs. Cells with three-dimensional electrodes realized by laser ablation are proven to have enhanced electrochemical performance compared to those with conventional two-dimensional electrodes, especially at fast charging/discharging. Nevertheless, laser structuring of electrodes is still limited in terms of achievable processing speed, and the upscaling of the laser structuring process is of great importance to gain a high technology readiness level. In the presented research, the impact of different laser structuring strategies on the electro-chemical performance was investigated on aqueous processed Li(Ni0.6Mn0.2Co0.2)O2 cathodes with acid addition during the slurry mixing process. Rate capability analyses of cells with laser structured aqueous processed electrodes exhibited enhanced performance with capacity increases of up to 60 mAh/g at high current density, while a 65% decrease in ionic resistance was observed for cells with laser structured electrodes. In addition, pouch cells with laser structured acid-added electrodes maintained 29–38% higher cell capacity after 500 cycles and their end-of-life was extended by a factor of about 4 in contrast to the reference cells with two-dimensional electrodes containing common organic solvent processed polyvinylidene fluoride binder. [ABSTRACT FROM AUTHOR]

Lithium-ion batteries are currently one of the most important energy storage devices for various applications. However, it remains a great challenge to achieve both high energy density and high-power density while reducing the production costs. Cells with three-dimensional electrodes realized by laser ablation are proven to have enhanced electrochemical performance compared to those with conventional two-dimensional electrodes, especially at fast charging/discharging. Nevertheless, laser structuring of electrodes is still limited in terms of achievable processing speed, and the upscaling of the laser structuring process is of great importance to gain a high technology readiness level. In the presented research, the impact of different laser structuring strategies on the electro-chemical performance was investigated on aqueous processed Li(Ni0.6Mn0.2Co0.2)O2 cathodes with acid addition during the slurry mixing process. Rate capability analyses of cells with laser structured aqueous processed electrodes exhibited enhanced performance with capacity increases of up to 60 mAh/g at high current density, while a 65% decrease in ionic resistance was observed for cells with laser structured electrodes. In addition, pouch cells with laser structured acid-added electrodes maintained 29–38% higher cell capacity after 500 cycles and their end-of-life was extended by a factor of about 4 in contrast to the reference cells with two-dimensional electrodes containing common organic solvent processed polyvinylidene fluoride binder.

LiNi0.6Co0.2Mn0.2O2 (NMC 622) cathode material is widely used for lithium-ion batteries. The effect of the method of creating a protective layer of Li1.3Al0.3Ti1.7(PO4)3 (LATP) on the electrochemical characteristics of commercial cathode material NMC 622 was investigated. It was found that both methods of LATP coating did not affect the crystal structure and morphology of NMC 622. The prototypes of Li-ion batteries with a cathode based on modified NMC 622 are characterized by significantly higher stability of capacitive characteristics during long charge/discharge cycling, compared with prototypes of Li-ion batteries based on the pristine cathode material. In addition, the protective layer of LATP, applied by the sol–gel method, can significantly increase the capacity of the cathode material NMC 622 at the high current density and reduce the capacity drop during the continuous charge/discharge cycling. Creating a protective layer of LATP via sol–gel method is an effective way to improve the electrochemical characteristics of cathode materials such as NMC 622. [ABSTRACT FROM AUTHOR]

Academic research in the battery field frequently remains limited to small coin or pouch cells, especially for new materials that are still rather far from commercialization, which renders a meaningful evaluation at an early stage of development challenging. Here, the realization of large lab‐scale pouch cells comprising Sn0.9Mn0.1O2 (SMO), prepared via an easily scalable hydrothermal synthesis method, as an alternative active material for the negative electrode and LiNi0.6Mn0.2Co0.2O2 (NMC622) as a commercially available active material for the positive electrode is reported. Nine double‐layer pouch cells are connected in series and parallel, suitable for powering a remote‐controlled vehicle. Subsequently, these SMO‖NMC622 cells are critically evaluated by means of an early‐stage life cycle assessment and compared to graphite‖NMC622 cells, in order to get first insights into the potential advantages and challenges of such lithium‐ion chemistry. [ABSTRACT FROM AUTHOR]

The electrochemical performance of lithium-ion batteries is directly influenced by type of active material as well as its morphology. In order to evaluate the impact of particle morphology in thick-film electrodes, Li(Ni0.6Mn0.2Co0.2)O2 (NMC 622) cathodes with bilayer structure consisting of two different particle sizes were manufactured and electrochemically characterized in coin cells design. The hierarchical thick-film electrodes were generated by multiple casting using NMC 622 (TA) with small particle size of 6.7 µm and NMC 622 (BA) with large particle size of 12.8 µm. Besides, reference electrodes with one type of active material as well as with two type of materials established during mixing process (BT) were manufactured. The total film thickness of all hierarchical composite electrodes were kept constant at 150 µm, while the thicknesses of TA and BA were set at 1:2, 1:1, and 2:1. Meanwhile, three kinds of thin-film cathodes with 70 µm were applied to represent the state-of-the-art approach. Subsequently, ultrafast laser ablation was applied to generate groove structures inside the electrodes. The results demonstrate that cells with thin-film or thick-film cathode only containing TA, cells with bilayer electrode containing TBA 1:2, and cells with laser-structured electrodes show higher capacity at C/2 to 5C, respectively.

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.

Lithium-ion batteries have become the most promising energy storage devices in recent years. However, the simultaneous increase of energy density and power density is still a huge challenge. Ultrafast laser structuring of electrodes is feasible to increase power density of lithium-ion batteries by improving the lithium-ion diffusion kinetics. The influences of laser processing pattern and film thickness on the rate capability and energy density were investigated using Li(Ni0.6Mn0.2Co0.2)O2 (NMC 622) as cathode material. NMC 622 electrodes with thicknesses from 91 µm to 250 µm were prepared, while line patterns with pitch distances varying from 200 µm to 600 µm were applied. The NMC 622 cathodes were assembled opposing lithium using coin cell design. Cells with structured, 91 µm thick film cathodes showed lesser capacity losses with C-rates 3C compared to cells with unstructured cathode. Cells with 250 µm thick film cathode showed higher discharge capacity with low C-rates of up to C/5, and the structured cathodes showed higher discharge capacity, with C-rates of up to 1C. However, the discharge capacity deteriorated with higher C-rate. An appropriate choice of laser generated patterns and electrode thickness depends on the requested battery application scenario; i.e., charge/discharge rate and specific/volumetric energy density. [ABSTRACT FROM AUTHOR]

This research will focus on characterising and analysing next generation batteries consisting of silicon-alloy/graphite blend anode combined with a nickel rich lithium nickel manganese cobalt oxide (NMC 622) as cathode. The study is performed on prototype pouch cells (1.4 Ah). Furthermore, the effect of applying external pressure on the pouch cell is investigated. The application of external pressure has a significant beneficial impact, more specifically a 19% increase in capacity combined with a significant decrease of 50% of the discharge ohmic resistance. To investigate and quantify the pressure variation over the state of charge (SoC) a dedicated set-up has been developed which allows to apply an external pressure while measuring the pressure variation. Up to 30 N of pressure variation is observed during static tests, while no pressure variation can be observed during short pulses, demonstrating its potential to use pressure as SoC estimator. Finally, a study on the effect of initial applied external pressure on the cells' lifetime has shown that the initial applied pressure, within the range of tested pressures, has little impact on the cells' performance and lifetime. [ABSTRACT FROM AUTHOR]

Lithium-ion batteries have become the most promising energy storage devices in recent years. However, the simultaneous increase of energy density and power density is still a huge challenge. Ultrafast laser structuring of electrodes is feasible to increase power density of lithium-ion batteries by improving the lithium-ion diffusion kinetics. The influences of laser processing pattern and film thickness on the rate capability and energy density were investigated using Li(Ni0.6Mn0.2Co0.2)O2 (NMC 622) as cathode material. NMC 622 electrodes with thicknesses from 91 µm to 250 µm were prepared, while line patterns with pitch distances varying from 200 µm to 600 µm were applied. The NMC 622 cathodes were assembled opposing lithium using coin cell design. Cells with structured, 91 µm thick film cathodes showed lesser capacity losses with C-rates 3C compared to cells with unstructured cathode. Cells with 250 µm thick film cathode showed higher discharge capacity with low C-rates of up to C/5, and the structured cathodes showed higher discharge capacity, with C-rates of up to 1C. However, the discharge capacity deteriorated with higher C-rate. An appropriate choice of laser generated patterns and electrode thickness depends on the requested battery application scenario; i.e., charge/discharge rate and specific/volumetric energy density.

The electrochemical performance of lithium-ion batteries is directly influenced by type of active material as well as its morphology. In order to evaluate the impact of particle morphology in thick-film electrodes, Li(Ni0.6Mn0.2Co0.2)O2 (NMC 622) cathodes with bilayer structure consisting of two different particle sizes were manufactured and electrochemically characterized in coin cells design. The hierarchical thick-film electrodes were generated by multiple casting using NMC 622 (TA) with small particle size of 6.7 µm and NMC 622 (BA) with large particle size of 12.8 µm. Besides, reference electrodes with one type of active material as well as with two type of materials established during mixing process (BT) were manufactured. The total film thickness of all hierarchical composite electrodes were kept constant at 150 µm, while the thicknesses of TA and BA were set at 1:2, 1:1, and 2:1. Meanwhile, three kinds of thin-film cathodes with 70 µm were applied to represent the state-of-the-art approach. Subsequently, ultrafast laser ablation was applied to generate groove structures inside the electrodes. The results demonstrate that cells with thin-film or thick-film cathode only containing TA, cells with bilayer electrode containing TBA 1:2, and cells with laser-structured electrodes show higher capacity at C/2 to 5C, respectively. [ABSTRACT FROM AUTHOR]

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. [ABSTRACT FROM AUTHOR]