Lithium–air battery Puns

I have been learning a little about batteries and I came across that lithium-air batteries are the most energetically dense there is but then I went looking to buy them and there are none for sale and then I had a doubt, these batteries really exist or are they only theoretical, and if they do not exist which are the most energy dense batteries on the market?

Hi, at work we need to ship lithium batteries that weight 52 kgs. It is my understanding that the air freight forwarders can not take batteries that weight more than 35 kgs.

Is there any way to ship via air these 52kg batteries?

Any thoughts or suggestions?

Worth a watch if you're in iron ore and/or lithium

https://www.youtube.com/watch?v=UDjgSSO98VI

1/10th the cost of Lithium-ion batteries, 2-3 times the energy density, improved carbon footprint.

Only apparent downside is that it is suitable for stationary applications. So maybe not cars but houses, power grids etc.

https://www.wsj.com/articles/startup-claims-breakthrough-in-long-duration-batteries-11626946330

>Backers [of Form Energy] include Breakthrough Energy Ventures, a climate investment fund whose investors include Microsoft Corp. co-founder Bill Gates and Amazon.com Inc. founder Jeff Bezos. Form recently initiated a $200 million funding round, led by a strategic investment from steelmaking giant ArcelorMittal SA, one of the world’s leading iron-ore producers.
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>Form is preparing to soon be in production of the “kind of battery you need to fully retire thermal assets like coal and natural gas” power plants, said the company’s chief executive, Mateo Jaramillo, who developed Tesla Inc.’s Powerwall battery and worked on some of its earliest automotive powertrains.