Comment by cconcepts | Hacker News Reader

Comment by cconcepts | Hacker News Reader

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In terms of mass energy storage from intermittent renewable sources, this seems like a winner - less cost means increased competitiveness for renewable energy.

However, it seems like energy density will be the winning factor in consumer battery tech which, as far as I can tell, appears to be a significant chunk of the EXISTING market. This is something that Na ion doesn't yet seem competitive at - which is not to say that it won't get better with time/investment/research.

Unless lithium gets crazy expensive, I don't see the battery being a big enough expense in a laptop or mobile phone for people to be willing to put up with more weight for an incremental price saving.

This is definitely great news for renewable energy though.

Sodium atoms have a much higher molecular weight (22.99 u) than Lithium atoms (6.94 u). This alone makes Lithium more competitive by weight in the long run.

The ideal battery consists of two electrodes where one consists purely of the alkali metal in the charged state and the other one is weightless at the charged state but then collects the metal oxide when discharging. The oxygen is ideally taken from the air.

Currently we are far from that ideal since the electrodes contain additional matrix materials, between the electrodes an electrolyte is present, the oxidizing agent is stored inside the battery requiring yet other chemicals to keep it stable. Then the battery needs a casing which adds more weight.

> consumer battery tech

Depends which consumers you're talking about. There are huge, untapped markets in Africa and Asia where people have no refrigeration or washing machines (partly due to having an insufficient electrical grid, or a complete lack of one), and they would benefit immensely from being able to store cheaply generated solar power.

A large enough battery system based on this tech might be out of reach for a single individual in those circumstances, but not for a group who pooled their money and shared it.

If you could build a giant battery the size of a large warehouse, on the cheap..... even people in Texas would be buying, as then all that wind could be used.

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