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This paper presents selected interim results of the H2020 project 3beLiEVe, which aims to deliver next-generation Lithium-Nickel-Manganese-Oxide (Generation 3b) battery cells for automotive applications, encompassing research activities across three pillars: (i) Selection and optimisation of the cathode (LNMO) and anode (Si/C) materials, as well as the high-voltage electrolyte, (ii) development and integration of cell-internal and external sensors, and demonstration at cell, module and pack level, (iii) demonstration of large-scale manufacturing capability and compatibility with a circular economy. This article shows selected results of the project achieved so far in these three pillars, aiming to inform the scientific community about some of the latest achievements of European research on Generation 3b Li-ion batteries.

Fabrication of SOFC cathodes by infiltration of LSCF into composite scaffolds were investigated. Two composite materials, LSF-YSZ and LSCrF-YSZ, were tested as potential SOFC cathode scaffolds for cells operating at 973K. Zr migration in LSF-YSZ scaffold was determined to be harmful, but changing the Sr dopant level in LSF was found to tune the Zr migration. LSCrF-YSZ scaffold was able to eliminate Zr migration, but the poor sinterability of the LSCrF hindered sintering of the electrolyte. Although problems still exist, both scaffolds showed improved performance at low LSCF loading due to the reduced ohmic loss.

Aim of this work is the development of a distributed charge-transfer numeric model for intermediate temperature solid oxide fuel cells (IT-SOFCs) with composite electrodes. The model describes the leakage current inside a mixed ionic electronic conducting (MIEC) electrolyte. The reaction interface is extended along the whole length of the electrodes and a one-dimensional description of charge transfer phenomena is entailed. The profiles of the ionic and the electronic current density, as well as the profiles of the ionic and the electronic potentials are described along the whole length of the cell. The model is applied to analyze the experimental results of IT-SOFCs based on Samarium doped Ceria (SDC) electrolytes, Cu-Pd-CZ80 anodes and LSCF cathodes. Hydrogen electro-oxidation experiments are examined first, then the analysis is extended to the simulation of OCV data collected when feeding biogas mixtures to the anode

A distributed charge transfer model for IT-SOFCs with MIEC electrolyte and composite electrodes is developed. A physically-based description of the electronic leakage current in the electrolyte is included, together with mass and charge conservation equations. The model is applied to simulate experimental polarization curves and impedance spectra collected on IT-SOFCs consisting of SDC electrolytes, Cu-Pd-CZ80 infiltrated anodes and LSCF/GDC composite cathodes. Hydrogen electro-oxidation experiments are examined (H2/N2 humidified mixtures, 700degC, 30-100% H2 molar fraction). A significant increase of the ohmic resistance measured in the impedance spectra is revealed at decreasing the H2 partial pressure or increasing the voltage (from 0.71 cm2 at 100% H2 to 0.81 cm2 at 30% H2). Good agreement between the calculated and experimental polarization and EIS curves is achieved by fitting the exchange current density and the capacitance of each electrode. Model and theoretical analyses allow to rationalize the observed shift of the ohmic resistance, highlighting the key-role played by the electronic leakage current. Overall, the model is able to capture significant kinetic features of IT-SOFCs, and allows to gain insight into relevant parameters for the optimal design of the cell (electrochemically active thickness, current and potential distribution, mass diffusion gradients).

Aim of this work is the development of a distributed charge-transfer numeric model for intermediate temperature solid oxide fuel cells (IT-SOFCs) with composite electrodes. The model describes the leakage current inside a mixed ionic electronic conducting (MIEC) electrolyte. The reaction interface is extended along the whole length of the electrodes and a one-dimensional description of charge transfer phenomena is entailed. The profiles of the ionic and the electronic current density, as well as the profiles of the ionic and the electronic potentials are described along the whole length of the cell. The model is applied to analyze the experimental results of IT-SOFCs based on Samarium doped Ceria (SDC) electrolytes, Cu-Pd-CZ80 anodes and LSCF cathodes. Hydrogen electro-oxidation experiments are examined first, then the analysis is extended to the simulation of OCV data collected when feeding biogas mixtures to the anode

Fabrication of SOFC cathodes by infiltration of LSCF into composite scaffolds were investigated. Two composite materials, LSF-YSZ and LSCrF-YSZ, were tested as potential SOFC cathode scaffolds for cells operating at 973K. Zr migration in LSF-YSZ scaffold was determined to be harmful, but changing the Sr dopant level in LSF was found to tune the Zr migration. LSCrF-YSZ scaffold was able to eliminate Zr migration, but the poor sinterability of the LSCrF hindered sintering of the electrolyte. Although problems still exist, both scaffolds showed improved performance at low LSCF loading due to the reduced ohmic loss.

A distributed charge transfer model for IT-SOFCs with MIEC electrolyte and composite electrodes is developed. A physically-based description of the electronic leakage current in the electrolyte is included, together with mass and charge conservation equations. The model is applied to simulate experimental polarization curves and impedance spectra collected on IT-SOFCs consisting of SDC electrolytes, Cu-Pd-CZ80 infiltrated anodes and LSCF/GDC composite cathodes. Hydrogen electro-oxidation experiments are examined (H2/N2humidified mixtures, 700°C, 30–100% H2molar fraction). A significant increase of the ohmic resistance measured in the impedance spectra is revealed at decreasing the H2partial pressure or increasing the voltage (from 0.71 Ω cm2at 100% H2to 0.81 Ω cm2at 30% H2). Good agreement between the calculated and experimental polarization and EIS curves is achieved by fitting the exchange current density and the capacitance of each electrode. Model and theoretical analyses allow to rationalize the observed shift of the ohmic resistance, highlighting the key-role played by the electronic leakage current. Overall, the model is able to capture significant kinetic features of IT-SOFCs, and allows to gain insight into relevant parameters for the optimal design of the cell (electrochemically active thickness, current and potential distribution, mass diffusion gradients).