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To merge Microsoft Excel files together, it is best to save them as CSV files first. Open the Excel files and in the menu bar, click File, Save As. In the Save as type drop-down list, select CSV (comma delimited) from the list.
Do this for each Excel file you want to merge, then place all the CSV files in the same folder. For ease, place them in a folder in the root of the C: drive (e.g. c:\csvfiles).
Open the Windows command prompt and navigate to the folder containing the CSV files. Type dir to view the files in the folder and ensure all the files are there.
Type in the below command to merge all CSV files in the folder into a new CSV file titled "newfile.csv" (any name could be used).
copy *.csv newfile.csv
Após a criação do novo arquivo, abra o novo arquivo CSV na Microsoft Excel e salve-o como um arquivo do Excel.