Technically speaking, a more powerful power supply can be used without any problems and does not pose any danger to your device, as it always draws as much energy as it currently needs. The only disadvantage is the usually higher price of the more powerful product.
Yes, as general rule this is possible. Although you have to consider the power capacity and the type of the connection.
Basically yes, you can use them to charge your laptop, however you have to make sure, that it has enough power to do so. To find out, if it has it, please compare the specifications on the back of the original power supply with those of the one, that came with your docking station. The output voltage should not differ more than 1 volt and the output power should be greater or equal to that of the original power supply.
In our shop we also offer combinations of docking stations and power supplies.
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