Well, to begin with, it's worth indicating that power stations are not strictly "generators", as they are often referred to because they do not generate
power. Instead, they are sources of electrical energy stored in a lithium battery that has been charged, which is released over time when connected to devices and appliances either in the process of charging or powering them.
Portable generators are in the main heavy ad unwieldy. Portable power stations on the other hand are generally light in weight with some small enough to be carried in a backpack.
Another important point where power stations differ a lot from portable generators is that they cannot compare in terms of power delivery, with the latter equipped with engines and therefore able to produce lots more while there is available fuel. Conversely, portable power stations are able to use solar panels to provide what manufacturers claim as limitless power availability (provided there is plenty of sun!).
Portable power stations do not themselves pollute like portable generators and are virtually silent (though fans can be heard when they come on to cool the unit).
While advances in the battery technology continue to offer improvements and impress casual onlookers, they are still some way off before their application in portable power stations can realistically be seen as a substitute for the power supplied by gas/LPG generators, about which we review some of the best in our sister site generatorjungle