How does `this` work in es6 object literal pattern?

Question

I am learning about the object literal pattern. Here is a pretty simple example of an object (es5) with some navigation functionality using jQuery. Take note of how this refers to the object navigation.

(function() {
    var navigation = {
        init: function() {
            this.cacheDom();
            this.bindEvents();
        },
        cacheDom: function() {
            this.$nav = $('nav');
            this.$hamburger = $('button.ham');
        },
        bindEvents: function() {
            this.$hamburger.click(this.toggleNav.bind(this));
        },
        toggleNav: function() {
            this.$nav.toggleClass('active');
        }
    }
    navigation.init();
})()

In ES6 and am having trouble understanding why I cannot reference this in the same way. Example code block:

(function() {
    var navigation = {
        init: () => {
            console.log(this)
            navigation.cacheDom();
            navigation.bindEvents();
        },
        cacheDom: () => {
            navigation.$nav = $('nav');
            navigation.$hamburger = $('button.ham');
        },
        bindEvents: () => {
            navigation.$hamburger.click(this.toggleNav.bind(this));
        },
        toggleNav: () => {
            navigation.$nav.toggleClass('active');
        }
    }
    navigation.init();
})()

In the above example this will log to the console. How can I let my object know that this refers to the object?

Any help appreciated, Thanks