<script>
    $(function(){
        $('#maisestrelas').click(function(){
            $.ajax({
               url:'application/views/includes/grava_estrela.php',
               type:'POST',
               dataType:'html',
               data:{},
               success:function(resp){
                 console.log(resp);
               }
            });

        });
    });
</script>

arquivo grava_estrela.php

<?php
$id = 12;
$query = $this->nome_model->verifica_voto($id)->row();
echo $query->id;

erro:<b>Fatal error</b>:  Using $this when not in object context in