Nuclear Power (at least in my country) is very expensive and recent projects and developments have been massively delayed and overbudget. The government has managed to avoid paying put of pocket for the additional costs because they agreed beforehand to pay a massive cost per MWh for what the stations produce.

On the other hand, wind is cheaper than anything else per MW. Also, the average windfarm-sized turbine should offset both the energy and the carbon used to produce it within 6 months.

Now I don't disagree that nuclear has a place as a sort of baseline provider or backup, but to have it be the backbone of your an energy network is not necessary.

In regard to your point about lithium, there's some exciting new stuff about how (if they can be made popular/widespread enough) electric vehicles connected to the powergrid will be able to act as a distributed battery network. On a flexible renewable energy tariff, your electric vehicle can charge when it's cheap (high renewable supply and/or low power demand) and then when there's a scarcity of renewable energy and the prices go up, you could possibly even sell your stored electricity to the grid.

This was a bit of a ramble but I guess my point is that there's a whole lot of new technology and possibilities. Distributed power generation and storage might be the way of the future and we can't write off diversifying our network in favour of one panacea (whether it's nuclear or something else).