Currently "Sodium Battery Cell" is priced at US$50–70/kWh on the Shanghai Metals...

		kragen 81 days ago \| parent \| context \| favorite \| on: Pakistan says rooftop solar output to exceed grid ... Currently "Sodium Battery Cell" is priced at US$50–70/kWh on the Shanghai Metals Market, which gives every appearance of being a real thing: https://www.metal.com/en/markets/43. They list LFP batteries currently at US$38–52/kWh: https://www.metal.com/en/markets/42 I think you may be dramatically overestimating how much container shipping costs.

("Shanghai Metals Market" is reportedly a consultancy which provides price data, not a market.)