4 ms·

$40/kWh sounds so fantastic, I can't believe it. Could you please provide a source for that price? Where will I get such cheap batteries?

toomuchtodo 1y ago
Not OP, but a recent auction in China has utility scale at $52/kWh. Given the cost decline curve of storage, I would assume we arrive at $40 within 1-2 years. https://news.ycombinator.com/item?id=44513185 https://news.ycombinator.com/item?id=44513185
- bryanlarsen 1y ago
  That $52/kWh is for more than batteries, it's for a fully packaged bulk storage system. So it's quite possible that we're already at $40/kWh for batteries.
  - toomuchtodo 1y ago
    Thank you, I will try to remember to include this on my next comment when referencing this cost point.
Tepix 1y ago
CATL sodium-ion batteries, currently in mass production. https://aukehoekstra.substack.com/p/batteries-how-cheap-can-they-get https://aukehoekstra.substack.com/p/batteries-how-cheap-can-... https://energynews.biz/catls-19-kwh-sodium-ion-claims-face-reality-check-in-1-82-billion-market/ https://energynews.biz/catls-19-kwh-sodium-ion-claims-face-r... https://www.nextbigfuture.com/2025/08/catl-sodium-ion-batteries-lower-cost-than-lithium-ion-batteries.html https://www.nextbigfuture.com/2025/08/catl-sodium-ion-batter...
- bb88 1y ago
  It is also worth noting that you can buy sodium ion batteries if you want to play around with them. The only trick is charging method is not the same as lithium ion, so they need a specialized charger. There are some sources on aliexpress. One listing sells a ~700Wh battery for around $76. So not quite $50/KWh but not awful either. The discharge curve is also different than lithium ion, so it's easy to see if you actually have a lithium ion battery or a sodium ion.
  - alecco 1y ago
    That sounds dangerous for inexperienced people.
    - Havoc 1y ago
      Sodium batteries are a lot safer than the lithium batteries usually used for hobby projects
    - kragen 1y ago
      Why, do they use pyrophoric electrolytes like Li-ion or something?

toomuchtodo 1y ago

Not OP, but a recent auction in China has utility scale at $52/kWh. Given the cost decline curve of storage, I would assume we arrive at $40 within 1-2 years. https://news.ycombinator.com/item?id=44513185 https://news.ycombinator.com/item?id=44513185

bryanlarsen 1y ago
That $52/kWh is for more than batteries, it's for a fully packaged bulk storage system. So it's quite possible that we're already at $40/kWh for batteries.
- toomuchtodo 1y ago
  Thank you, I will try to remember to include this on my next comment when referencing this cost point.

Tepix 1y ago

CATL sodium-ion batteries, currently in mass production. https://aukehoekstra.substack.com/p/batteries-how-cheap-can-they-get https://aukehoekstra.substack.com/p/batteries-how-cheap-can-... https://energynews.biz/catls-19-kwh-sodium-ion-claims-face-reality-check-in-1-82-billion-market/ https://energynews.biz/catls-19-kwh-sodium-ion-claims-face-r... https://www.nextbigfuture.com/2025/08/catl-sodium-ion-batteries-lower-cost-than-lithium-ion-batteries.html https://www.nextbigfuture.com/2025/08/catl-sodium-ion-batter...

bb88 1y ago
It is also worth noting that you can buy sodium ion batteries if you want to play around with them. The only trick is charging method is not the same as lithium ion, so they need a specialized charger. There are some sources on aliexpress. One listing sells a ~700Wh battery for around $76. So not quite $50/KWh but not awful either. The discharge curve is also different than lithium ion, so it's easy to see if you actually have a lithium ion battery or a sodium ion.
- alecco 1y ago
  That sounds dangerous for inexperienced people.
  - Havoc 1y ago
    Sodium batteries are a lot safer than the lithium batteries usually used for hobby projects
  - kragen 1y ago
    Why, do they use pyrophoric electrolytes like Li-ion or something?