This is controlled by the web-mode-tag-auto-close-style
variable:
Tag auto-close style:
0=no auto-closing
1=auto-close with </
2=auto-close with > and </.
The default value is 1
. Disable automatic tag closing completely with
(eval-after-load "web-mode"
'(setq web-mode-tag-auto-close-style 0))