Beijing Airport transit please

Hello,
I will be traveling from Vientiane, Laos to Geneva, Switzerland this weekend, and I have to transit at BJ airport.
My flight schedule is given below:

QV445 Lao Airlines 18:35 Vientiane 19:40 Bangkok

CA980 Air China 01:00 Bangkok 06:30 BJ

CA861 Air China 13:30 BJ 18:25 Geneve

I was told by Laos Airline that they can only check in my luggage to BJ.I don't know if I would need a Chinese visa in BJ. I am not going to leave the airport, but I am sure I would have to leave the transit area, because I would have to get my luggage from the flight from Bangkok, pass customs and security and then check in for my next flight to Geneva.

Will I need a Chinese visa to pass security and check in for my second flight to Geneva? since I already have a seat booked on my next flight and I will leave the airport before 24 hrs. Information on the Chinese embassy website doesn't state what happens if you have to leave the transit area and collect luggage before connecting the next flight.

I have a Nigerian passport and hold a Switzerland residence permit B.
Thank you.