Dendrite deflection when propagating under compressive load. For 𝜎𝜎 𝑎𝑎𝑎𝑎𝑎𝑎𝑎𝑎𝑎𝑎𝑎𝑎𝑎𝑎 = 200 MPa, the metal propagation direction turned about 90°to align with the loading axis. Deflection of a propagating dendrite in response to load. Initially, the dendrite propagates along the segment highlighted in blue under galvanostatic conditions (0.2 mA/cm 2 ). Upon application of 70 MPa compressive stress, deflection of the dendrite along the first red segment occurred. Load removal, and reloading, produced the second blue and red segments, respectively. Image recorded while viewing through the cantilever (viewing direction opposite to that in Fig. ); solid-electrolyte is 90 μm thick. All plating occurred at voltages within the LLZTO electrolyte window (voltage and current data available in the Supplementary Information).