$phpExcel = $this->getPHPExcel();
$sheet = $phpExcel->getActiveSheet();

$sheet->getStyle('A1:C1')->applyFromArray(array(
    // Alignment
    'alignment' => array(
        'horizontal' => PHPExcel_Style_Alignment::HORIZONTAL_CENTER,
        'vertical' => PHPExcel_Style_Alignment::VERTICAL_CENTER,
        'rotation' => 0,
        'wrap' => true
    ),

    // Font
    'font' => array(
        'name' => 'Arial',
        'bold' => true,
        'italic' => false,
        'underline' => PHPExcel_Style_Font::UNDERLINE_DOUBLE,
        'strike' => false,
        'size' => 12
        'color' => array(
            'rgb' => 'FF0000'
        ),
    ),

    // Borders
    'borders' => array(
        'bottom' => array(
            'style' => PHPExcel_Style_Border::BORDER_DASHDOT,
            'color' => array(
                'rgb' => '808080'
            )
        ),
        'top' => array(
            'style' => PHPExcel_Style_Border::BORDER_DASHDOT,
            'color' => array(
                'rgb' => '808080'
            )
        ),
        'allborders' => array(
            'style' => PHPExcel_Style_Border::BORDER_DASHDOT,
            'color' => array(
                'rgb' => '808080'
            )
        )
    ),

    // Border
    'allborders'/'bottom'/'diagonal'/'horizontal'/'inside'/'left'/'outline'/'right'/'top'/'vertical' => array(
        'style' => PHPExcel_Style_Border::BORDER_DASHDOT,
        'color' => array(
            'rgb' => '808080'
        )
    ),
    
    // NumberFormat
    'numberformat' => array(
        'code' => PHPExcel_Style_NumberFormat::FORMAT_CURRENCY_EUR_SIMPLE,
    ),

    // Protection
    'protection' => array(
        'locked' => true,
        'hidden' => false
    ),

    // FILL
    'fill' => array(
        'type' => PHPExcel_Style_Fill::FILL_GRADIENT_LINEAR,
        'rotation'   => 0,
        'startcolor' => array(
            'rgb' => '000000'
        ),
        'endcolor' => array(
            'argb' => 'FFFFFFFF'
        )
    )
));