Unless other situations where the established technology wins due to inertia, sodium ion batteries have two benefits that make them interesting regardless:

Firstly, they are safer. A punctured sodium ion battery doesn't catch fire, which massively simplifies safety design. That makes them very attractive for certain scenarios, especially ones where density is a secondary concern. That in turn means they get further development money instead of withering on the vine.

Secondly, they require fewer hard-to-obtain materials, which makes them attractive from a strategic perspective. This one should be less important than the safety factor but it's also relevant.

I'm pretty sure we'll actually see wet sodium cells in the wild if they are actually practical. Sodium ion tech is already being commercialized and if this brings it within the same ballpark as lithium ion then it becomes a very interesting choice for vehicles due to instant crash safety gains.

They have slightly lower density right now, but there is work to increase the density, and it could very well get up to about 210wh/kg which would put it directly on par with current lithium ion batteries. So it could replace the low end of the EV market without any significant change except for a reduction in price by a lot.

Voltaire was a French poet.

Alessandro Volta was the electrochemist.

JFC..what do they teach in schools any more?

LI-ion is pretty efficient compared to NA-ION.

at room temperature, but in the real world, where it gets cold, sodium batteries have an advantage.

Li-ion technology has huge factories behind it, so economies of scale apply here. The first Na-ion battery factories have just started, so everything is more expensive to manufacture on a small scale. However, the ingredients are cheaper and easily available. Once they ramp up production, we can make a fair comparison between the two.

I have a feeling LIBs are going to be more expensive, but they won’t disappear since high energy density is very handy in mobile applications like cars and phones. NIBs are probably going to end up being a lot cheaper, which should make them a popular option in all the less demanding applications, like grid energy storage, kitchen scales, and anything in between.