Thr IRF2804 may not be a good choice due to the Vgs(thr) rating (look at Fig 3 for 5V). Most heatbed drivers are controlled by the MCU directly so you need to select what is commonly referred to as a logicalLevel MOSFET or subLogicLevel. It's a good idea to check what the RDSon for 4.5V is if they don't claim to be Logic Level driven.
I've always recommened IRLB8743 or IRLB3034/IRLB3036 as good ones to use. IRLB3034/IRLB3036 are usually more expensive but have better RDSon (specially the IRLB3034) and sometimes can be found when the IRLB8743 isn't available.
I've always recommened IRLB8743 or IRLB3034/IRLB3036 as good ones to use. IRLB3034/IRLB3036 are usually more expensive but have better RDSon (specially the IRLB3034) and sometimes can be found when the IRLB8743 isn't available.