Yes. Custom elements require a closing tag. Only certain tags in HTML are allowed to be self-closing due to the parser.
The following is a complete list of the void elements in HTML:
area, base, br, col, command, embed, hr, img, input, keygen, link, meta, param, source, track, wbr
and :
A non-void element must have an end tag, unless the subsection for that element in the HTML elements section of this reference indicates that its end tag can be omitted.
http://www.w3.org/TR/html-markup/syntax.html#syntax-elements