Low-expansion composite electrodes for all-solid-state batteries

An all-solid-state electrochemical cell that cycles lithium ions comprising:

• a first solid-state electrode comprising:
• a solid-state electroactive material in the form of a plurality of particles that undergoes volumetric expansion and contraction during cycling of the electrochemical cell,
• wherein each particle of the plurality of particles comprises a plurality of intraparticle pores and has an average porosity ranging from greater than or equal to about 10% to less than or equal to about 75%, and
• wherein the intraparticle pores of the solid-state electroactive material accommodate the volumetric expansion and contraction of the solid-state electroactive material inwardly so to minimize outward expansion of the plurality of particles in the first solid-state electrode;
• and
• a solid-state electrolyte in the form of a plurality of solid-state electrolyte particles that are intermingled with and contacting the solid-state electroactive material,
• wherein the first solid-state electrode has an average interparticle porosity between the solid-state electroactive material particles and the solid-state electrolyte particles ranging from greater than or equal to about 0% to less than or equal to about 40%, and
• wherein the interparticle porosity together with the intraparticle pores minimize micro-cracking and delamination within the all-solid-state electrochemical cell;
• and
• a second solid-state electrode opposing the first solid-state electrode;
• and
• a separator disposed between the first solid-state electrode and the second solid-state electrode.