All-Solid-State Batteries Using Rationally Designed Garnet Electrolyte Frameworks

Functioning
bulk-type all-solid-state batteries in a practical
form factor with composite positive electrodes, using Al-substituted
Li7La3Zr2O12 (LLZO) as
the solid electrolyte, have been demonstrated for the first time.
The devices incorporate bilayers composed of dense LLZO membranes
and porous LLZO scaffolds infiltrated with LiNi0.6Mn0.2­Co0.2O2 and other components
as positive electrodes, combined with lithium anodes. The porous scaffolds
are prepared using an easily scaled freeze-tape-casting method. The
unidirectional pores of the scaffold facilitate infiltration of cathode
components and shorten lithium ion diffusion path lengths, while the
addition of a soft ionically conductive solid to the scaffold ensures
good contact among the components.