I just dont see any reason to ever invest into it nowadays, when renewables and batteries have gotten so good.

Renewables and batteries have their own problems.

Producing and processing cobalt and lithium under current conditions will mean engaging in large-scale deforestation in some of the last unmolested corners of the planet, producing enormous amounts of toxic waste as part of the refinement process, and then getting these big bricks of lithium (not to mention cadmium, mercury, and lead) that we need to dispose of at the battery's end of lifecycle.

Renewables - particularly hydropower, one of the most dense and efficient forms of renewable energy - can deform natural waterways and collapse local ecologies. Solar plants have an enormous geographic footprint. These big wind turbines still need to be produced, maintained, and disposed of with different kinds of plastics, alloys, and battery components.

Which isn't even to say these are bad ideas. But everything we do requires an eye towards the long-term lifecycle of the generators and efficient recycling/disposal at their end.

Nuclear power isn't any different. If we don't operate plants with the intention of producing fissile materials, they run a lot cleaner. We can even power grids off of thorium. Molten salt reactors do an excellent job of maximizing the return on release of energy, while minimizing the risk of a meltdown. Our fifth generation nuclear engines can use this technology and the only thing holding us back is ramping it up.

Unlike modern batteries, nuclear power doesn't require anywhere near the same amount of cobalt, lithium, nickel and manganese. Uranium is surprisingly cheap and abundant, with seawater yielding a pound of enrichable uranium at the cost of $100-$200 (which then yields electricity under $.10/kwh).

We can definitely do renewables in a destructive and unsustainable way, recklessly mining and deforesting the plant to churn out single-use batteries. And we can do nuclear power in a responsible and efficient way, recycling fuel and containing the relatively low volume of highly toxic waste.

But all of that is a consequence of economic policy. Its much less a consequence of choosing which fuel source to use.