AngularJS: How to export ui-grid data to excel with custom HTML?

Question

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AngularJS: How to export ui-grid data to excel?

I like this answer but if I have a custom HTMl in grid for example chart :

https://plnkr.co/edit/irskqERheTOiFql82QFC?p=preview

  $scope.gridOptions.columnDefs = [
    { field:'name' },
    { field:'gender' },
    { field: 'spark', cellTemplate: 'sparkline-cell.html', width: 100 }
  ];

how can I export this cells to Excel.