You Do Need power plug adapter while traveling from Cayman Islands to Cape Verde.

Here is Why You Need An Adapter

The outlet and plug type used in Cape Verde are C and F and in Cayman Islands are A and B. This is how they look like.

Cayman Islands

In Cayman Islands, outlets of type A and B are in use.

Type A

Type B

Cape Verde

In Cape Verde, outlets of type C and F are in use.

Type C

Type F