CPAP battery rules

I am traveling to China, and am aware that there are CCC rules that apply to domestic flights, but there are also instances where this is enforced for international flights.

I am carrying a portable CPAP battery (Medistrom Pilot 24 Plus) with me, and will be having both the instruction booklet and doctor prescription with me. I’m bringing the battery pack as I’m taking a red eye flight in, and will be using it in flight.

What are the rules and risks of the power bank being confiscated?