Technically it is the battery inside the blower that needs to be charged. If you are a team and can switch the blowers between you it is easy to take off the filter and pull out the blower and put in a charged blower, put back the filter (if it is okay to use again, that depends on circumstances) and you are ready to go again. If you are on your own and only have one blower you will have to wait until the blower is fully charged again.
There is a powerful battery as an accessory. It will work for at least 8 hours on one full charging. Check the external battery.