"CATL’s “Naxtra” sodium-ion batteries achieve an energy density of up to 175 Wh/kg, the company said, putting it on par with lithium iron phosphate (LFP) batteries."
Useful, but not a "breakthrough" in energy density. More like another good low-end option.
Sodium is a lot more abundant than lithium. Scaled up this could be a breakthrough in battery cost per kWh.
The benefits are cold performance, durability and potentially price in the future.
Isn’t the benefit that it is durable and has much higher charge/discharge amperage limits?
A battery that can charge as fast as you can pump electricity into it, as many times as you want opens up a lot of possibilities.
E.g. a car that has a 200 mile range and a 5 minute charging time is way more useable than a car with 300 miles of range that takes an hour to charge.