For stopping an EC2 instance via PowerShell, you can use the Stop-EC2Instance cmdlet. You need to use an instance ID with the cmdlet. You can get an instance ID using the Get-EC2Instance cmdlet by passing the instance reservation ID. EC2 instances that use Amazon EBS volumes as their root devices can be quickly stopped and started via PowerShell. When an EC2 instance is stopped, the compute resources are released; and you are not billed for an hourly instance usage for the instance. Even though you stop the instance, you will still have your root partition holding data on the EBS volume, and you are charged for EBS volume usage. You can restart your instance at any time.
To stop an EC2 instance, you can use this:
PS C:\> Stop-EC2Instance -InstanceId i-0cab647fc9e824f2c
