New hybrid and ionic polymer electrolytes for lithium metal solid state batteries

Los capítulos 1 y 2 están sujetos a confidencialidad por la autora 182 p.The rising need for the development of the electric transportation requires batteries with higher energy densities. Lithium metal batteries look to be the most promising technology. Nonetheless, common organic liquid electrolytes cannot be used, due to their poor chemical stability towards the lithium and the formation of dendrites. Solid state batteries, where the liquid electrolyte is replaced by a solid ionic conductor, enable to reach higher energy density, are safer and can mitigate dendrites formation. In this thesis, we report new hybrid and polymer solid electrolytes to couple with a lithium metal anode. For this purpose, we developed ionic polymer matrices based on poly(ethylene glycol) derivatives. For the hybrids, we choose to use garnet nanoparticles Li7La3Zr2O12 (LLZO) as active inorganic fillers. The performance of the hybrid and polymer solid electrolytes was carried out in lithium symmetrical solid-state batteries. The study of voltage shapes at different current densities reveals about the homogeneity of Li stripping/plating processes and the formation of Li dendrites

Single-ion polymer/LLZO hybrid electrolytes with high lithium conductivity

Hybrid solid electrolytes which combine the properties of inorganic and polymeric ion conductors are being investigated for lithium batteries which use lithium metal anodes. The number of inorganic/polymer compositions and their synergy in ion-conducting properties are limited by the hybrid fabrication method and the limited compatibility between both types of materials. Here we report a hybrid solid electrolyte formed by a poly(ethylene glycol) type single-ion polymer network and ceramic garnet-type nanoparticles of Li7−3XAlXLa3Zr2O12 (LLZO) with very high lithium conductivity. The combination of a lithium-single ion polymer matrix with LLZO inorganic particles results in flexible free-standing films by using a fast UV-photopolymerization process with facile control of its composition. This methodology showed excellent dispersion of the LLZO nanoparticles within the gel polymer network with up to 50 wt% ceramic content, as shown in the enviromental ESEM images. These hybrid electrolytes have high ionic conductivity values (1.4 × 10−4 S cm−1 at 25 °C) and high lithium transference number as compared to previous hybrid electrolytes. The effect of LLZO nanoparticle content on the lithium transport was investigated in detail using solid-state nuclear magnetic resonance spectroscopy (NMR). Finally, determination of the critical current density (CCD) before lithium dendrites are initiated has been carried out on both pristine and hybrid electrolytes, so as to assess their potential as solid electrolytes for lithium metal batteries.This work was supported by the European Commission’s funded Marie Sklodowska-Curie project POLYTE-EID (Project No. 765828). L.P. has received funding from the European Union’s Horizon 2020 research and innovation programme under the Marie Skłodowska–Curie grant agreement No 797295

Comparison of efficacy and safety of single versus repeated intra-articular injection of allogeneic neonatal mesenchymal stem cells for treatment of osteoarthritis of the metacarpophalangeal/metatarsophalangeal joint in horses: A clinical pilot study.

The purpose of this prospective study was to evaluate the effects of single and repeated intra-articular administration of allogeneic, umbilical cord-derived, neonatal mesenchymal stem cells (MSC) in horses with lameness due to osteoarthritis (OA) of a metacarpophalangeal joint (MPJ). Twenty-eight horses were included. Horses were divided into two groups. Horses in group MSC1 received an MSC injection at M0 and a placebo injection at M1 (1 month after M0). Horses in group MSC2 received MSC injections at M0 and at M1. Joint injections were performed with a blinded syringe. Clinical assessment was performed by the treating veterinarian at M1, M2 and M6 (2 and 6 months after M0), including lameness evaluation, palpation and flexion of the joint. Radiographic examination of the treated joints was performed at inclusion and repeated at M6. Radiographs were anonymized and assessed by 2 ECVDI LA associate members. Short term safety assessment was performed by owner survey. A 2-month rehabilitation program was recommended to veterinarians. There was a significant improvement of the total clinical score for horses in both groups. There was no significant difference in the total clinical score between groups MSC1 and MSC2 at any time point in the study. There was no significant difference in the total radiographic OA score, osteophyte score, joint space width score and subchondral bone score between inclusion and M6. Owner-detected adverse effects to MSC injection were recorded in 18% of the horses. Lameness caused by OA improved significantly over the 6-month duration of the study after treatment with allogeneic neonatal umbilical cord-derived MSCs combined with 8 weeks rest and rehabilitation. There is no apparent clinical benefit of repeated intra-articular administration of MSCs at a 1-month interval in horses with MPJ OA when compared to the effect of a single injection

Superionic Diffusion through Frustrated Energy Landscape

Solid-state materials with high ionic conduction are necessary for many technologies, including all-solid-state lithium (Li)-ion batteries. Understanding how crystal structure dictates ionic diffusion is at the root of the development of fast ionic conductors. Here, we show that LiTi2(PS4)3 exhibits a Li-ion diffusion coefficient about an order of magnitude higher than that of current state-ofthe-art Li superionic conductors. We rationalize this observation by the unusual crystal structure of LiTi2(PS4)3, which offers no regular tetrahedral or octahedral sites for Li to favorably occupy. This creates a smooth, frustrated energy landscape resembling the energy landscapes present in liquids more than those in typical solids. This frustrated energy landscape leads to a high diffusion coefficient, combining low activation energy with a high pre-factor