I would take a look at the Laerdal LSU suction device. https://www.laerdal.com/gb/nav/21/Suction-Units
You can get the batteries from various suppliers and modify the unit to whatever supplier of suction liner that you have.
I have used them clinically and service them and find them robust and practical. You can also have wall mounted docking stations that recharge them, these can also be mounted on various systems such as incubators and trolleys.