Add <br> to the cell excel with PHP

I am going to create a excel with php, but to convert into excel I just created the table with HTML and setup the header:

  header("Pragma: public");
    header("Expires: 0");
    header("Cache-Control: must-revalidate, post-check=0, pre-check=0"); 
    header("Content-Type: application/force-download");
    header("Content-Type: application/octet-stream");
    header("Content-Type: application/download");
header ("Content-Disposition: inline; filename=XLS_".$dati[0]['cognome'].".xls");
header("Content-Transfer-Encoding: bina开发者_StackOverflow社区ry");

If I add the <br> into the cell, the document show a new cell every <br> that I added. I don't want a new cell every <br>. There is a special char to say "new line".

Or if there is a good library and easy to use?