Laravel/Eloquent 5 whereBetween not worl

Use Laravel 5

I would like get rows included between 2 dates in my database (sqlite), I use this command:

        $trackers = Tracker::whereBetween('detect_at', [$date1, $date2])->where("serial", "uhu")->get();

But reply nothing.

Entire request :

        $date1 = "2015-07-13 03:53:38";
        $date2 = "2015-07-13 03:58:36";
        $trackers = Tracker::whereBetween('detect_at', [$date1, $date2])->where("serial", "uhu")->get();

example of one row in my database :

id   serial  latitude   longitude   altitude    accuracy    detect_at                     created_at               updated_at
728  uhu    48.0491     -1.74138    0           20          2015-07-13 03:54:38           2015-07-02 13:40:15         2015-07-02 13:40:15

I don't understand, I need help thx ^^