Newsletter #1 / November 2022

Welcome to the first SUBLIME newsletter. We want to keep you informed about ongoing tasks and report on major breakthroughs during the project. SUBLIME started in May 2020, right at the beginning of the COVID-19 pandemic. In spite of this global tragedy, all consortium members stayed dedicated to their tasks and kept SUBLIME’s vision in sight, i.e. the development of a complete value chain centering around new sulfide electrolyte based solid-state battery cells with high capacity and high voltage stability.

Three milestones have been reached so far
The first milestone, Specification of requirements regarding performances, cost and safety was already reached early in the project in Oct. 2020. All specifications and requirements on the final costs of the battery cells as well as their safety were reported in D2.1 (Report on specifications, performances, and cost requirements for the large cell). End of 2020 the second milestone Protocol for safe handling and testing defined was passed, keeping the project in line with the work plan. Handling and testing protocols for the sulfide electrolyte components were established, thus increasing safety and reproducibility of the data.
During summer 2022 and after lots of efforts to characterize and optimize the cell components, the first technical milestone was reached, i.e. Lab-scale cell ready. The gained knowledge and experience will further be used for upscaling and processing at pouch cell level.

Upcoming milestones include
– assembly of pouch cells (up to 40 mAh)
– definition of recycling paths
– the delivery of materials at kg scale.

Major results so far

Materials development
Development of the sulfide electrolyte has entered the final stage. Ionic conductivities of more than 1 mS/cm could be obtained. The manufacturing process has been upscaled and more than 500 g of the sulfide electrolyte can be produced in a single batch.

Figure 1, +500 g batches of the sulfide electrolyte could be manufactured showing ionic conductivities of more than 1 mS/cm

Li metal protective layers have been investigated for use in sulfide-electrolyte based cells. AIMD simulations on a range of different model systems revealed promising coating layers for Li metal anodes. Materials, reducing the degradation processes at the Li-electrolyte interface, though, at the same time exhibiting high enough ionic conductivity to sustain higher C-rates, were proposed.

Electrolyte film and composite cathode processing
Different approaches are taken to evaluate the best processing parameters for all-solid-state battery cells using sulfide electrolytes. Dry processing of the materials was used for a preliminary characterization of their performance and evaluation of their compatibility with each other. Wet-processing by solution casting and extrusion is further applied to prepare electrolyte layers and composite cathodes, as well as bilayer assemblies. Different polymeric binders and binder combinations have been selected and their effect on the performance of all-solid-state cells have been investigated.

Figure 2, Homogenous and freestanding electrolyte films could be developed.

Furthermore, composite cathodes have been developed. Major processing parameters were optimized including the morphology and particle size of the active material and sulfide electrolyte particles, the amount and quality of the conducting additive, the active material-to-solid electrolyte (AM:SE) ratio, as well as the amount and quality of the binder material. Thus, improvements in the first cycle discharge capacity by more than 50% could be achieved.

Figure 3, Performance improvements could be achieved by optimization of the processing conditions for the composite electrode

Conferences & Events

It was a busy summer 2022 for SUBLIME and many dissemination activities were conducted. After the return of face-to-face meetings, it was nice to see the community come back together to share results on common research topics. A short summary is presented below:

SUBLIME @ Power Our Future 2022
SUBLIME was heavily represented at the “Power our Future 2022” conference at CICenergiGUNE in Vitoria-Gasteiz (Spain) from 5th to 8th of July 2022. Two oral and one poster contribution were presented in the 4 day event.

Contributions:
- Electrochemical properties and ageing of all-solid-state batteries with argyrodite electrolyte
(Vladislav Kolotygin/ CICe; oral)
- Influence of binder-solvent combinations on ionic conductivity of Li6PS5Cl electrolyte films
(Alexander Beutl/ AIT; oral)
- Infiltration process of sulfide based solid electrolyte solutions into conventional electrodes
for solid-state batteries (Artur Tron/ AIT; poster)

SUBLIME @ Ceramics in Europe 2022
The “Ceramics in Europe 2022” took place from 10th to 14th of July, gathering scientists from all over the world. SUBLIME was also represented with an oral contribution about the influence of different processing routines on the electrochemical performance of all-solid-state batteries.

Contributions:
- Electrochemical behaviour of dry-processed and slurry-casted all-solid-state batteries with argyrodite electrolyte (Vladislav Kolotygin/ CICe; oral)

SUBLIME @ Giornate dell’Elettrochimica Italiana 2022
The Division of Electrochemistry of the Italian Chemical Society continued their annual Congress after a two-year forced break. SUBLIME could contribute to the event which took place from 11th to 14th of September 2022 in Orvieto, Italy. A poster was presented on results obtained from modelling of the interface between Li metal and sulfide-based electrolytes.

Contributions:
- Modeling of Lithium-ion battery with sulfide-based solid-state electrolyte (Davide Dessantis/ POL; poster)

Figure 4, f.l.t.r, Davide Dessantis (POL) presenting his work at the GEI 2022, Alexander Beutl (AIT), and Artur Tron (AIT), and Vladislav Kolotygin (CICe) at the POWER OUR FUTURE 2022

Furthermore, SUBLIME was presented at several exhibitions, symposia and workshops throughout summer 2022, including the International Vienna Motor Symposium, HyVolution, the Car Symposium Bochum, and the Battery Experts Forum.

Figure 5, SUBLIME exhibition booths at various events

6th General Assembly @ CEA
On 19th and 20th October 2022, the 6th SUBLIME - General Assembly took place at the premises of CEA in Grenoble, France. It was the second hybrid meeting since the beginning of the project and participants both on site and online could discuss together the current status of the ongoing work packages.

Upcoming Events
Fall 2022 will continue to be an exciting period. The TRA 2022 is just around the corner at which SUBLIME will participate as part of the LC-BAT-1 research and innovation cluster. An Invited Session on batteries will be organized and held together with the LC-BAT-5 and LC-BAT-10 (Collabat) research and innovation clusters.

Moreover, an oral contribution will be made at the IBPC2022 in Braunschweig, discussing the results on composite cathode optimization.

Publications

Molecular-Level Insight into the Interfacial Reactivity and Ionic Conductivity of a Li-Argyrodite Li6PS5Cl Solid Electrolyte at Bare and Coated Li-Metal Anodes, ACS Appl. Mater. Interfaces 13, 43734 (2021)
Golov, A., Carrasco, J
https://doi.org/10.1021/acsami.1c12753

Enhancing first-principles simulations of complex solid-state ion conductors using topological analysis of procrystal electron density, npj Comput Mater 8, 187 (2022)
Golov, A., Carrasco, J
https://doi.org/10.1038/s41524-022-00877-6

Current Status of Formulations and Scalable Processes for Producing Sulfidic Solid-State Batteries, Batteries & Supercaps e202200328 (2022)
Batzer, M., Heck, C., Michalowski, P., Kwade, A.
https://doi.org/10.1002/batt.202200328

Meet the TEAM

A Meet the TEAM section will be implemented on the project homepage soon with updates from our colleagues from AIT. Find out about their role in the project and what it means for them to work in the field of battery science.