By Dr. Michelle Tokarz, VP of Partnerships and Innovation, and Dr. Nathanael Downes, Research Scientist

Batteries power the tools and materials all around us from everyday household items to vehicles to medical devices to grid storage. The demand for sustainable, rechargeable, long-lasting batteries to power more and more of our daily lives has led to a surge in research on how to create a better battery. Through its Endurion project, The Coretec Group is developing a unique silicon anode battery material to improve cycling stability, run times, and energy density in lithium-ion batteries.   

The way a lithium-ion battery’s four main parts – cathode, anode, separator, and electrolyte – work is that the lithium-ions flow from the anode through the electrolyte and separator to the cathode during discharge and from the cathode through the electrolyte and separator to the anode during charge/recharge. In order to obtain the necessary voltages for industrial applications, typically, several cells are combined to create a battery pack. Battery packs, comprised of multiple battery cells, can in turn be combined to form battery modules. 

Run time, safety, cycle life, power, energy density, and costs are the battery performance goals that can be improved upon and are the reason for the increase in industry research. 

Dr. Nathanael Downes, Research Scientist, has been working in The Coretec Group’s wet lab to create silicon anode material for characterization testing. The results of these tests help determine which materials to use to create the electrode slurry – a mix of solid, conductive particles along with active materials, polymer binders, and a solvent. Each of the ingredients in the slurry, along with the amounts and order of addition to the mix impact the effectiveness of the electrode in a lithium-ion battery. 

Last week, Dr. Michelle Tokarz, VP of Partnerships and Innovation, and Dr. Downes worked in the University of Michigan Battery Lab (UMBL) making slurries, building battery cells, and running cycle testing.  

See their insights on their experiences at UMBL below:

1. What was your overall impression of UMBL?

Dr. Tokarz: The depth of knowledge of the UMBL team was most helpful in our work. They worked side by side with us and gave us useful guidance.   

Dr. Downes: The battery lab has state-of-the-art equipment. It was a great experience working with it.   

2. What was the most important thing you learned during your week in the UMBL?

Dr. Tokarz: The importance of the right “casting” quality – namely things like how volatile the solvent is, the particle size, the presence/absence of a “skin”, etc. Getting the right chemistry and slurry characteristics are the keys to success. 

Dr. Downes: The importance of collaboration and teamwork. We were fortunate to have Joe Gallegos to help orient and assist us in the Battery Lab which helped us be more efficient in our work there. 

3. What surprised/didn’t surprise you the most while at the UMBL?

Dr. Tokarz: We were prepared, as we always are, to hunker down and complete our work with just the two of us but were delighted to find a staff that was more than ready to help out. The comradery and collaboration made for a wonderful lab experience. 

Dr. Downes: The art of making a good slurry is more than putting together all the ingredients. A discerning hand, a keen eye, and exacting standards are required.  

4. What are your goals for future tests of The Coretec Group’s silicon anode materials?

Dr. Tokarz: With the UMBL in our backyard, there’s always the possibility of making additional slurries and/or cells for further testing. 

Dr. Downes: Ultimately, to more exhaustively explore the variations in electrode formulation to find the best recipe and to apply those variations to cell production. 

5. What are you most excited about when working with technologies like these?  

Dr. Tokarz:  The ability to work “hands-on” in a facility dedicated to battery work. The equipment was suited to exactly what we needed, and we had oversight from UM Battery lab staff. This experience will complement our work in our own wet lab perfectly.  

Dr. Downes: The opportunity to work with state-of-the-art equipment and with the knowledgeable and experienced staff at UM. 

6. Where do you see the biggest advancements in battery R&D over the next year?

Dr. Tokarz: With the known critical material shortages worldwide, it is important to be able to “get more out of” our batteries. Silicon active material is one way to do that, and many researchers are working on creative ways to get access to the increased charge capacity of silicon while also working with the challenges.  

Dr. Downes: The significant funding increase from the federal government will have a huge impact in alternative battery technologies and battery manufacturing.