Angular2, Reloading browser page decodes URL ['=' to '%3D']

Question

I already researched a lot due to this problem, but couldn't find anything yet. When I use my web-application by clicking on links, the browser is redirecting me without any problems. But when I reload my browser by pressing F5 or the Reload button, my URL gets decoded, turning from

http://localhost:4200/#/kalender;kuerzel=name/list to http://localhost:4200/#/kalender;kuerzel%3Dname/list

causing the following error:

Error: Uncaught (in promise): Error: Cannot match any routes. URL Segment: 'kalender;kuerzel%3Dname/list'

That is the part of the code generating the link:

...
    else {
        this.router.navigate(
            ['.', {kuerzel: this.calendarStore.addSelectedEmployee(query).join()}],
            {relativeTo: this.route}
    );

I get that problem only when I reload my browser. I am new here, so, if you need more information just ask.