I have another laptop besides a V570, and when that laptop has finished charging the charger light turns blue.
I haven't noticed any indicator light that tells me when my battery is fully charged. How can I tell if my laptop is fully charged without having to switch on the computer?
You have to switch on your laptop.
Look for the battery icon located at the bottom right of your screen. Once your laptop is fully charged it will disappear. Otherwise it will show you the percentage of power charged in your battery.