From Lab to Manufacturing Line: Guidelines for the Development and Upscaling of Aqueous Processed NMC622 Electrodes

Lithium-ion batteries (LIBs) have facilitated the transition to a more sustainable energy model. Paradoxically, current high energy cathodes are industrially processed using organic solvents, which are deleterious for the environment. In this work, LiNi0.6Mn0.2Co0.2O2 (NMC622) high-energy cathode electrode was prepared at laboratory scale following a more environmentally friendly aqueous route. Several steps in the preparation of the electrodes (such as the drying temperature, drying air flux or pH buffering) were thoroughly optimized to enhance the quality of the water-processed electrodes. Afterwards, the recipe developed at laboratory scale was upscaled to a semi-industrial electrode coating line, to analyze the viability of the developed processing conditions into a realistic electrode manufacturing environment. The electrodes obtained were tested in full coin cells using graphite-based anodes as counter electrodes. Interestingly, the cycling performance of the cells based on water-processed electrodes was higher than that of organic-processed ones. It is evidenced that it is possible to manufacture electrodes for high energy density LIBs following environmentally friendly, cheaper, and industrially implementable electrode processing methods with no-penalty in the electrochemical performance.This work has received funding from the European Union's Horizon 2020 research and innovation programme under grant agreements No 769929 (IMAGE) and No 814464 (Si-DRIVE)

Reduction of Grain Boundary Resistance of La0.5Li0.5TiO3 by the Addition of Organic Polymers

The organic solvents that are widely used as electrolytes in lithium ion batteries present safety challenges due to their volatile and flammable nature. The replacement of liquid organic electrolytes by non-volatile and intrinsically safe ceramic solid electrolytes is an effective approach to address the safety issue. However, the high total resistance (bulk and grain boundary) of such compounds, especially at low temperatures, makes those solid electrolyte systems unpractical for many applications where high power and low temperature performance are required. The addition of small quantities of a polymer is an efficient and low cost approach to reduce the grain boundary resistance of inorganic solid electrolytes. Therefore, in this work, we study the ionic conductivity of different composites based on non-sintered lithium lanthanum titanium oxide (La0.5Li0.5TiO3) as inorganic ceramic material and organic polymers with different characteristics, added in low percentage (<15 wt.%). The proposed cheap composite solid electrolytes double the ionic conductivity of the less cost-effective sintered La0.5Li0.5TiO3.We thank the Spanish Ministry for Science and Technology (MAT2007-64486-C07-05) and CDTI (ALMAGRID of the "CERVERA Centros Tecnológicos" program, CER-20191006) for financial their support. JS, AV, SG, and FG also want to acknowledge Agencia Española de Investigación /Fondo Europeo de Desarrollo Regional (FEDER/UE) for funding the projects PID2019-106662RB-C41, C42, C43, and C44

Influence of the Ambient Storage of LiNi0.8Mn0.1Co0.1O2 Powder and Electrodes on the Electrochemical Performance in Li-ion Technology

Nickel-rich LiNi0.8Mn0.1Co0.1O2 (NMC811) is one of the most promising Li-ion battery cathode materials and has attracted the interest of the automotive industry. Nevertheless, storage conditions can affect its properties and performance. In this work, both NMC811 powder and electrodes were storage-aged for one year under room conditions. The aged powder was used to prepare electrodes, and the performance of these two aged samples was compared with reference fresh NMC811 electrodes in full Li-ion coin cells using graphite as a negative electrode. The cells were subjected to electrochemical as well as ante- and postmortem characterization. The performance of the electrodes from aged NM811 was beyond expectations: the cycling performance was high, and the power capability was the highest among the samples analyzed. Materials characterization revealed modifications in the crystal structure and the surface layer of the NMC811 during the storage and electrode processing steps. Differences between aged and fresh electrodes were explained by the formation of a resistive layer at the surface of the former. However, the ageing of NMC811 powder was significantly mitigated during the electrode processing step. These novel results are of interest to cell manufacturers for the widespread implementation of NMC811 as a state-of-the-art cathode material in Li-ion batteries.This work was supported by European Union’s Horizon 2020 research and innovation programme [No. 814389 (SPIDER project)]; and the CDTI—Ministerio De Ciencia e Innovación’s ‘CERVERA Centros Tecnológicos’ program [CER-20191006 (ALMAGRID project)]. V.P. and T.R. also wish to thank the funding from Gobierno Vasco/Eusko Jaurlaritza (IT-1226-19)

Associative Conditioning Is a Robust Systemic Behavior in Unicellular Organisms: An Interspecies Comparison

The capacity to learn new efficient systemic behavior is a fundamental issue of contemporary biology. We have recently observed, in a preliminary analysis, the emergence of conditioned behavior in some individual amoebae cells. In these experiments, cells were able to acquire new migratory patterns and remember them for long periods of their cellular cycle, forgetting them later on. Here, following a similar conceptual framework of Pavlov’s experiments, we have exhaustively studied the migration trajectories of more than 2000 individual cells belonging to three different species: Amoeba proteus, Metamoeba leningradensis, and Amoeba borokensis. Fundamentally, we have analyzed several relevant properties of conditioned cells, such as the intensity of the responses, the directionality persistence, the total distance traveled, the directionality ratio, the average speed, and the persistence times. We have observed that cells belonging to these three species can modify the systemic response to a specific stimulus by associative conditioning. Our main analysis shows that such new behavior is very robust and presents a similar structure of migration patterns in the three species, which was characterized by the presence of conditioning for long periods, remarkable straightness in their trajectories and strong directional persistence. Our experimental and quantitative results, compared with other studies on complex cellular responses in bacteria, protozoa, fungus-like organisms and metazoans that we discus here, allow us to conclude that cellular associative conditioning might be a widespread characteristic of unicellular organisms. This new systemic behavior could be essential to understand some key principles involved in increasing the cellular adaptive fitness to microenvironments.This work was supported by a grant of the University of Basque Country (UPV/EHU), GIU17/066, the Basque Government grant IT974-16, the UPV/EHU and Basque Center of Applied Mathematics, grant US18/21, and the Israel Science Foundation (536/19)Peer reviewe

Methodology for the characterization and understanding of longitudinal wrinkling during calendering of lithium-ion and sodium-ion battery electrodes

"The manufacturing of lithium-ion battery (LIB) cells is following a complex process chain in which the individual process steps influence the subsequent ones. Meanwhile, increasing requirements especially concerning the battery performance, sustainability and costs are forcing the development of innovative battery materials, production technologies and battery designs. The calendering process directly affects the volumetric energy density of an electrode and therefore of a battery cell. Calendering is still challenging as it causes high stresses in the electrode that lead to defects and thus increased rejection rates. The interaction between electrode material and process as well as the formation of defects is still not fully understood, especially when new material systems are used. In this context, the sodium-ion battery (SIB) is one post-lithium battery system that is a promising option to overcome the limitations of conventional LIBs. Therefore, this paper presents a first material and machine independent methodology to describe and understand the defect type longitudinal wrinkle, which mostly appears at the uncoated current collector edge of an electrode and in running direction. The aim is to systematically characterize the longitudinal wrinkles according to their geometry. The automatic data acquisition is carried out with a laser triangulation system and a 3D scanning system. The geometry values are calculated from the raw data and correlated to selected process parameters. The methodology is applicable regardless of the material as shown by exemplary results of NMC811 cathodes for LIB and hard carbon anodes for SIB. By using two different pilot calenders it is shown, that the data acquisition can be carried out independently of the machine. The presented methodology contributes to finding solutions for the avoidance of longitudinal wrinkling in any battery electrode and therefore to reducing the rejection rate.

Evidence of conditioned behavior in amoebae

Associative memory is the main type of learning by which complex organisms endowed with evolved nervous systems respond efficiently to certain environmental stimuli. It has been found in different multicellular species, from cephalopods to humans, but never in individual cells. Here we describe a motility pattern consistent with associative conditioned behavior in the microorganism Amoeba proteus. We use a controlled direct-current electric field as the conditioned stimulus, and a specific chemotactic peptide as the unconditioned stimulus. The amoebae are capable of linking two independent past events, generating persistent locomotion movements that can prevail for 44 min on average. We confirm a similar behavior in a related species, Metamoeba leningradensis. Thus, our results indicate that unicellular organisms can modify their behavior during migration by associative conditioning.We would like to thank Dr. Andrew Goodkov from the Institute of Cytology (Russian Academy of Science) St. Petersburg, Russia, for valuable advices related to Amoeba organisms, Laura Perez Gomez and Luis Rojo Garcia for their assistance designing Fig. 1 and the AutoCAD 3D model, A-M Perez Biedermann for her valuable contribution in our study, Jose Gonzalez Romero and Jose Miguel Perez Perez from the Institute of Parasitology and Biomedicine "Lopez-Neyra" for their technical assistance. In addition, we thank Maria Calleja-Felipe for her valuable help in the peptide gradient experiments. This work was supported by a grant of the University of Basque Country (UPV/EHU), GIU17/066, the Basque Government grant IT974-16, and by the UPV/EHU and Basque Center of Applied Mathematics, grant US18/21"

Computational and Experimental Evaluation of the Immune Response of Neoantigens for Personalized Vaccine Design

In the last few years, the importance of neoantigens in the development of personalized antitumor vaccines has increased remarkably. In order to study whether bioinformatic tools are effective in detecting neoantigens that generate an immune response, DNA samples from patients with cutaneous melanoma in different stages were obtained, resulting in a total of 6048 potential neoantigens gathered. Thereafter, the immunological responses generated by some of those neoantigens ex vivo were tested, using a vaccine designed by a new optimization approach and encapsulated in nanoparticles. Our bioinformatic analysis indicated that no differences were found between the number of neoantigens and that of non-mutated sequences detected as potential binders by IEDB tools. However, those tools were able to highlight neoantigens over non-mutated peptides in HLA-II recognition (p-value 0.03). However, neither HLA-I binding affinity (p-value 0.08) nor Class I immunogenicity values (p-value 0.96) indicated significant differences for the latter parameters. Subsequently, the new vaccine, using aggregative functions and combinatorial optimization, was designed. The six best neoantigens were selected and formulated into two nanoparticles, with which the immune response ex vivo was evaluated, demonstrating a specific activation of the immune response. This study reinforces the use of bioinformatic tools in vaccine development, as their usefulness is proven both in silico and ex vivo.This work was supported by Basque Government funding (IT456-22; IT1448-22, IT693-22 and IT1524-22; ONKOVAC 2021111042), as well as by the UPV/EHU (GIU20/035; US21/27; US18/21; PIF18/295) and Basque Center of Applied Mathematics (US21/27 and US18/21)

Machine learning-based assessment of the impact of the manufacturing process on battery electrode heterogeneity

Electrode manufacturing process strongly impacts lithium-ion battery characteristics. The electrode slurry properties and the coating parameters are among the main factors influencing the electrode heterogeneity which impacts the battery cell performance and lifetime. However, the analysis of the impact of electrode manufacturing parameters on the electrode heterogeneity is difficult to be quantified and automatized due to the large number of parameters that can be adjusted in the process. In this work, a data-driven methodology was developed for automatic assessment of the impact of parameters such as the formulation and liquid-to-solid ratio in the slurry, and the gap used for its coating on the current collector, on the electrodes heterogeneity. A dataset generated by experimental measurements was used for training and testing a Machine Learning (ML) classifier namely Gaussian Naives Bayes algorithm, for predicting if an electrode is homogeneous or heterogeneous depending on the manufacturing parameters. Lastly, through a 2D representation, the impact of the manufacturing parameters on the electrode heterogeneity was assessed in detail, paving the way towards a powerful tool for the optimization of next generation of battery electrodes