Researchers from Lancaster University in England have developed a technique that allows them to see the 3D internal structure of rechargeable batteries for the first time.
The team was led by Professor Oleg Kolosov from Lancaster’s Physics Department in collaboration with University College London and NEXGENNA Faraday Institution Consortium, the university said in a news release.
The study, published in Nature Communications, used a novel 3D Nano-Rheology Microscopy (3DNRM) -based technique to visualise the 3D nanostructure inside rechargeable batteries, from the molecular scale electrical double-layer to the nanoscale-thick electrochemical surface layer on the graphite anode surface in a lithium-ion battery.
This allowed for the first time to directly observe the progression of the entire three-dimensional structure of the solid electric interface (SEI), a nanoscale passivation layer formed on the battery electrode-electrolyte interface that determines key battery properties.
The researchers also discovered key predictors of SEI layer formation in a complex interplay of molecular dimension electrical double-layer structures, surface properties of carbon layers, and solvent-Li ion interactions in the electrolyte.
They claim that the nanoarchitecture of solid-liquid interfaces is crucial for high-performance batteries, but that reaction interfaces inside batteries have been challenging to characterise because of their inherently difficult access.
The lead author, Dr Yue Chen, stated that understanding the SEI formation mechanism is still one of the most difficult and understudied areas because there is no interfacial characterisation technique that can operate with nanoscale resolution and in a working battery environment.
The authors said the dynamics of interfacial reactions govern chemical species transfer and define energy flow and conversion in important physical, chemical, and biological processes ranging from catalytic reactions, energy storage and release in batteries, to antigen-antibody interactions and information transmission across neural cells.
Moving forward, the Lancaster researchers said their study opens up a wide range of areas for the new technique from energy storage and chemical engineering to biomedical applications.
