Now i found the solution, but i dont know why. I include "win32clipboard"
import os, sys
import win32com.client
import win32clipboard
def Copy():
win32clipboard.OpenClipboard()
# Pfad zum Template
path_to_temp = r"C:\004_Python_Workspace\Persek\Template.xls"
# Pfad zum Testpaket
xlsPath = r"C:\004_Python_Workspace\Testfolder\Testanweisung_LK_ASL.xls"
# Blattname im Template und im Testpaket
Sheet = 'ECU_Config'
excel_app = win32com.client.dynamic.Dispatch('Excel.Application')
###### Kopiere ECU_Config aus Template #####
excel_workbook1 = excel_app.Workbooks.Open(path_to_temp)
excel_workbook1.Worksheets(Sheet).UsedRange.Copy()
###### Fuege in das neue Testpaket ein #####
excel_workbook2 = excel_app.Workbooks.Open(xlsPath)
excel_workbook2.Worksheets(Sheet).Range('A1').PasteSpecial()
excel_workbook2.worksheets(Sheet).Columns('A:B').AutoFit()
excel_workbook2.Close(SaveChanges=True)
del excel_workbook2
excel_workbook1.Close()
del excel_workbook1
excel_app.Quit()
win32clipboard.CloseClipboard()