Improved technologies for storing electricity are crucial for many facets of energy use ranging from better batteries for mobile devices and electric cars to large-scale power buffers for greatly expanded use of wind and solar resources on the electric grid.

University of Michigan energy researchers are working to overcome these challenges through a multi-pronged approach that enhances the capability of batteries that use established materials while developing the next generation batteries that need to pack more energy and be safer.

This work is highlighted in recent advances including:

  • An innovative laser-patterning process for producing three-dimensional graphite anode architectures that can enable highly efficient fast-charging of lithium-ion batteries, done through a collaboration among UMEI faculty affiliates Katsuyo Thornton, Jeff Sakamoto and Neil Dasgupta along with their students and colleagues.
  • Advances in the use of Electrochemical Impedance Spectroscopy (EIS) to more effectively probe the intrinsic properties of materials used for lithium-ion battery cathodes and other energy applications, led by UMEI faculty affiliate Katsuyo Thornton.
  • New insights into how to craft composite electrodes suitable for making solid-state batteries, obtained through sophisticated analysis of the material stresses that ultimately cause their degradation by UMEI faculty affiliates Jeff Sakamoto, Katsuyo Thornton and colleagues.
  • Breakthrough coupling of solid-state electrolytes with a Li-metal anode to create a path for developing inherently safe batteries with high energy density. Graduate student Michael Wang and Professor Jeff Sakamoto in a Nature Communications article have demonstrated the holy grail of battery anodes, namely, an anode made out of pure, in situ-formed Lithium metal.

A figure from Nature Communications showing the expected gains in energy density from the solid states batteries with pure and in situ-formed Lithium metal.

These items are just a small sample of work that draws on the deep bench of expertise among UMEI faculty affiliates who are advancing progress in materials science and engineering for energy applications. A wide range of creative collaborations are underway among U-M leaders in solid-state electrolytes, the engineering of material interfaces, in situ electrochemistry, atomistic and multi-physics modeling, electro- and thermo-chemical characterization, materials synthesis, nano-scale fabrication, electrochemical architecture, and related specializations.

Fig.1:

Fig. 1. Schematic illustration of anode fabrication processes showing slurry casting, calendered conventional high-tortuosity graphite anode, and highly ordered laser-patterned electrode (HOLE) design. Li-ion concentration gradients are reduced in the HOLE architecture due to the improved ionic transport in the vertical pore channels.

Fig 2:

Fig 2 Top-down and cross-sectional SEM images of the (a–d) HOLE anode and (e–g) conventional high-tortuosity anode.  3-D surface reconstructions from high-resolution optical microscope images showing the shape of tapered pore channels.

 

Graphical Abstract of advances in the sse of Electrochemical Impedance Spectroscopy (EIS):

Graphical Abstract of material stresses that cause solid-state battery degradation: