Electrochromic sheet and electrochromic device

An electrochromic sheet comprising:

• a support layer;
• an electrolyte layer provided over the support layer;
• an electrochromic layer provided over at least one surface of the electrolyte layer;
• and
• a sealing part provided to cover at least a side surface of the electrolyte layer,
• wherein an amount of deformation measured according to the following procedure i is 0.01 mm to 0.09 mm,
• Procedure i:
• a test piece (having a maximum length of 20 mm or more) in which the electrolyte layer is located at a central part and the sealing part is located at an outer edge is produced by using the electrochromic sheet, the test piece is chucked at both ends by a chucking part, the central part of the test piece is pressed at 30 N for 30 seconds, and a difference in depth between the central part of the test piece before being pressed and the central part of the test piece after being pressed is defined as an amount of deformation (mm).