GexSi1−x alloys have demonstrated synergetic effects as lithium-ion battery (LIB) anodes because silicon brings its high lithium storage capacity and germanium its better electronic and Li ion conductivity.
Light-induced structural changes of g-As45S55 were probed both by macro FT-Raman and energy-dependent micro-Raman spectroscopy. We suppose that new observed features in the Raman spectra of As-rich As-S glass are related to transformations of As4S4 molecules. Being initially in the structure of g-As45S55 closed and connected with glassy network only by weak Van der Vaals forces α(β)-As4S4 molecules are transformed into pararealgar pAs4S4 form during laser illumination. The effectiveness of transformations depends mainly from photon energies used for irradiation but transformation tendency observed for all used photon energies ranged from 1.65 to 2.54 eV. Observed Raman features and their structural origin are discussed. Theoretical and experimental investigations in the last years shown that chalcogenide glassy semiconductors (ChGS) continuous media are formed in a wide variety of basic short range order structural units (s. u.) than their crystal analogs [1-3]. The majorities are combined into the middlerange ordering (MRO) grouping (clusters), depending on concentration of additives and producing technology [4-6]. The ordering groups’ geometry in ChGS system' s bulk glasses and films determines physical properties [6,7]. During the few years a great importance starts to be given to structural fluctuations and separated nano-scale phases with homopolar As-As bonds for interpreting photo-induced phenomena in binary As-S glasses [8,9]. The concentration of nano-phases, n.f.~1.02.0 % in g-As2S3 is much larger than that of charged defects (Cdef~1 p.p.m.) which is foreseen by model [10,11]. The model of charged defects [10,11] in glass is known for a long time and has been the most widely spread one used to explain the photo-induced absorption in ChGS. This model is also used to explain the optical behavior in ChGS induced by the light with the energy of photons (E) lower than the Tauc band gap ( 0) in the Urbach edge region of optical absorption spectra. We have experimentally revealed that the introduction of HgS into g-As2S3 increases the absorption in the weak absorption region and is accompanied by the separation of β-As4S4 [12]. However, the
Among the alternative host materials for solid polymer electrolytes (SPEs), polycarbonates have recently shown promising functionality in all-solid-state lithium batteries from ambient to elevated temperatures. While the computational and experimental investigations of ion conduction in conventional polyethers have been extensive, the ion transport in polycarbonates has been much less studied. The present work investigates the ionic transport behavior in SPEs based on poly(trimethylene carbonate) (PTMC) and its co-polymer with ε-caprolactone (CL) via both experimental and computational approaches. FTIR spectra indicated a preferential local coordination between Li(+) and ester carbonyl oxygen atoms in the P(TMC20CL80) co-polymer SPE. Diffusion NMR revealed that the co-polymer SPE also displays higher ion mobilities than PTMC. For both systems, locally oriented polymer domains, a few hundred nanometers in size and with limited connections between them, were inferred from the NMR spin relaxation and diffusion data. Potentiostatic polarization experiments revealed notably higher cationic transference numbers in the polycarbonate based SPEs as compared to conventional polyether based SPEs. In addition, MD simulations provided atomic-scale insight into the structure-dynamics properties, including confirmation of a preferential Li(+)-carbonyl oxygen atom coordination, with a preference in coordination to the ester based monomers. A coupling of the Li-ion dynamics to the polymer chain dynamics was indicated by both simulations and experiments.
Scientific publications constitute the main information source of battery-related data for academic research. There is an impressive number of papers published on Lithium Ion Batteries (LIBs) for instance. Such impressive amount of data in principle could be used by machine learning (ML) methods in order to optimize efforts and even make possible the discovery of new optimal experimental conditions. Yet, the majority is published as unstructured data, making ML analysis difficult. Here, in order to unravel researchers’ habits when reporting their results, we present a text mining study using primarily publications containing original experimental data from the LIB field. We analyze the reported data structure and we discuss the remaining challenges for applying automated knowledge discovery techniques. We then present a Named Entity Recognition approach to automatically extract quantified parameters from the battery literature and how to build an in house generated database containing a wide diversity of materials, experimental parameters and conditions. Our in house approach achieves a data extraction F-scores ≥ 90% and can thereby pave the way towards an automatized way of generating large databases for use in battery ML models. References El-Bouysidy, H., Lombardo, T., Primo, E. N., Duquesnoy, M., Morcrette, M., Johansson, P., Simon, P., Grimaud, A., & Franco, A. A. submitted (2020). Torayev, Amangeldi, Pieter CMM Magusin, Clare P. Grey, Céline Merlet, and Alejandro A. Franco. Journal of Physics: Materials 2, no. 4 (2019): 044004.
New lithium salts for non-aqueous liquid, gel and polymeric electrolytes are crucial due to the limiting role of the electrolyte in modern lithium batteries. The solvation of any lithium salt to form an electrolyte solution ultimately depends on the strength of the cation-solvent vs. the cation-anion interaction. Here, the latter is probed via HF, B3LYP and G3 theory gas-phase calculations for the dissociation reaction: LiX <--> Li(+) + X(-). Furthermore, a continuum solvation method (C-PCM) has been applied to mimic solvent effects. Anion volumes were also calculated to facilitate a discussion on ion conductivities and cation transport numbers. Judging from the present results, synthesis efforts should target heterocyclic anions with a size of ca. 150 A(3) molecule(-1) to render new highly dissociative lithium salts that result in electrolytes with high cation transport numbers.
We propose a nano-fibrous polymer (NFP) film, fabricated by electrospinning poly(2,2,6,6-tetramethylpiperidinyloxy-4-yl methacrylate) (PTMA), as a key component in high performance organic batteries. The new strategy with a NFP film enables extraordinary rate capability and excellent cyclability, due to its special morphology. Moreover, the NFP film enhances the flexibility of the electrode at a low cost and prevents dissolution of PTMA into the electrolyte.
New lithium imide salts have been studied using computational chemistry methods. Intrinsic anion oxidation potentials and ion pair dissociation energies are presented for six lithium sulfonyl imides (R-O2S-N-SO2-R) and six lithium phosphoryl imides (R2-OP-N-PO-R2), as a function of -F, -CF3, and -C≡N substitution. The modelled properties are used to estimate the electrochemical oxidation stability of the anions and the relative ease of charge carrier creation in lithium battery electrolytes. The results show that both properties are improved with cyano-substitution, which in part is corroborated when comparing with other classes of lithium salts. However, the comparison also shows ambiguous oxidation stability results for cyano-substituted reference salts of the type PFx(CN)6−x− and BFx(CN)4−x−, using two different approaches – we present a tentative explanation for this. For the imide anions and PF6−, the bond dissociation energy is introduced as a third property, to gauge the thermal stability of the imide anions. The results suggest that the C-S and C-P bonds are the most liable to break and that the thermal stability is inversely related to the ion pair dissociation energy.
True North: This Guest Editorial introduces the NordBatt Special Collection, dedicated to the conference series of the same name. The Guest Editors reflect on the beginnings of the conference series and its evolution over the past 10 years. All great things have humble beginnings. In 2013 when NordBatt started, we had no lithium-ion battery manufacturing in the Nordic countries and we had rather few EVs on the roads, although things were clearly starting to move – Tesla Model S in fact topped the monthly new car sales of Norway in September that very year. Yet, even if the field was advancing and lively, relatively few Nordic research groups were doing any kind of battery R&D. Now, in 2023, almost everything is different; batteries and “electrify everything” are seen, not only by us, as the next industrial revolution – it is a topic gathering considerably many more actors in academia as well as in the whole ecosystem of batteries. But not all is new. The feeling we already had back then in 2013 – the very special Nordic collaboration climate and community – remains and it has also been reinforced by the NordBatt conference series. When the community gathered in Uppsala in 2013, we were a relatively small community – most people already knew each other and met anyhow in different settings – and NordBatt was clearly dominated by academics. Today we are more diverse, but at large the legacy and the core remain. The idea of NordBatt came from Kristina Edström, who brought us all in to Ångström Advanced Battery Centre and set the standard for further meetings: concise 2–3 day meetings (every 2nd year), focus on allowing many (younger) researchers to present (including poster presentations), and be inclusive in terms of battery technologies and topics. In addition, the conference would have some prominent international non-Nordic battery scientists as invited keynote/plenary speakers. At NordBatt 2013, Dominique Guyomard, Bor Yann Liaw and Robert Armstrong were the very first strong trio out, and they have since been followed by, e. g., Saiful Islam, Petr Novak, Noshin Omar, Bernd Friederich, Martin Winter, Jerry Barker, and Celine Merlet. The success commonly felt at NordBatt, alongside many dedicated initiatives starting both at national and European levels (not really any large Nordic effort!), gave a push to continue the series. We also agreed early on to embrace the Baltic countries and to emphasize the social side: excursions and dinners. Ever since, during its five meetings (Table 1), NordBatt has grown in size and attention, and is now an established respected venue. It is also almost growing out of its costume as a small-medium sized meeting where informal interactions are emphasized is not totally compatible with the growth. On the positive side, we find much more diversity in topics and speakers – with the most notable change being the many battery producers and start-ups willing to present and share their experiences, strategies, and future plans. # Year Venue Chair (s) Number of attendees 1 2013 Uppsala University, Uppsala, Sweden Kristina Edström 126 2 2015 Norwegian University of Science and Technology, Trondheim, Norway Fride Vullum-Brauer 90 3 2017 University of Oulu, Kokkola, Finland Ulla Lassi 127 4 2019 Technical University of Denmark, Lyngby, Denmark Jonathan Højberg and Paul Norby 168 5 2022 Chalmers University of Technology, Gothenburg, Sweden Patrik Johansson 230 This Special Collection gathers a few directions of research present in the Nordic battery community at present, such as: applied studies of NMC811 and LNMO lithium-ion battery cathodes, both by experiments and modelling; materials for sodium-ion batteries; several less common battery technologies: aluminum metal batteries, vanadium redox-flow batteries, and lithium-ion capacitors; a couple of popular electrolyte concepts: solid-state and local highly concentrated electrolytes; and also moving beyond the cell to state-of-health and circular economy models. The Special Collection is also a half-stop celebrating the legacy of NordBatt's first 10 years and pointing to the future 10 years or more – next in line is NordBatt at UiO, Norway, in September 2024. We foresee this meeting to be even larger and longer – not the least as Norway is the global role model for electrification and all Nordic countries are at the forefront of the green energy transition. We all look forward to meeting you at future NordBatt conferences and please enjoy the science presented in the NordBatt Special Collection!
