Store external API expire time in Custom Module

Question

I use ajax to get the access token from the external API. How can I store the expired time across the site and the ajax only call again when the session expired?

test.js

/helloworld/index/display is the controller that will get the input from Store -> Configuration and call the external API by using cURL

$.ajax({
    url: "/helloworld/index/display",
    type: "GET",
    complete: function (response) {
        access_token = response.responseText;
    }
});