Add bcc to back to stock alert notification

I am struggling to add bcc to back in stock alert notification.
I would like the mail to be sent to customer and bcc admin.
I’ve tried adding the addBcc part but did not work.

    Mage::getModel('core/email_template')
   // NOT WORKING ->addBcc('email@domain.com')
        ->setDesignConfig(array(
            'area'  => 'frontend',
            'store' => $storeId
        ))->sendTransactional(
            $templateId,
            Mage::getStoreConfig(self::XML_PATH_EMAIL_IDENTITY, $storeId),
            $this->_customer->getEmail(),
            $this->_customer->getName(),
            array(
                'customerName'  => $this->_customer->getName(),
                'alertGrid'     => $block
            )