Genuine question - what is the thought process behind this comment?

Because we both know that gas generators also require a production step... arguably one that's quite a bit more complex than a battery, at ~$1,000,000/MW of installation costs. And that installation of that complex is going to be very carbon intensive (even the concrete foundation alone...).

And then on top the plant actively burns hydrocarbons for the entirety of its existence.

So fill me in here - what is the exact argument you are trying to make with this?

The good 'ole "Lets start with the premise that all energy in our calculation comes from coal transported by truck, and then work out how "green" these technologies are"

Over the lifetime of the battery it’s not that bad and gets better as the carbon intensity of the grid that runs the factories improves.

that's a one time cost over many years that's quickly amortized. lets assume an upfront cost of ~100kg CO2 per kWh of battery storage and 250g of CO2 per kWh generated by a gas turbine. this means the carbon ROI is there after 400 kWh.

Compared to gas generators? Probably. And unlike gas there's no ongoing cost.

Not particularly, relative to producing anything, including turbines and the fuel to run them. (And then you have to burn that fuel...)

you have to look at CO2/kwh produced over the lifetime, that's the useful metric here

The extraction cost of minerals is only paid once. And a few big batteries will be much easier to recycle than a billion small ones in consumer electronics.