How much will be the cost for the pay-in lounge at Beijing Capital airport T2?

Hi!
We will be arriving in Beijing at around 1 am and we are planning to take a rest first in the airport until around 7 am instead of checking-in in our hotel (since we will be rated for another night) How much would be the cost for the pay-in lounge in airport terminal 2? the Beijing Capital Airport's website does not say anything about the price.

Please help us. Thank You in advance!