Submitted 4 days ago by ProdigalFrog@slrpnk.net to energy@slrpnk.net
https://www.youtube.com/watch?v=nPaRs1jllZQ
The sodium-ion performance info in that video seems a bit off. Afaik they are mainly cheaper and with more sustainable materials, but a bit less performant than lithium ion and thus not that suitable for increasing the range of EVs etc.
But still, for cheaper small electric city vehicles and stationary applications they will probably be quite nice.
What about the performance info is wrong, may I ask?
Sodium ion has far higher lab-tested cycle count than standard lithium ion/LiPo (3000-6000 cycles vs 300-500, max 1000 cycles) though in reality since sodium iron batteries are a chemistry that has been around for a few years instead of decades, real world is only 1000-3000 for the first generation while lithium iron phosphate still beats it with 3000-5000 cycles real-world, though that lithium chemistry is significantly more expensive, but indeed relevant to grid storage.
Sodium ion batteries also have a much broader temperature range (-40 to 80C vs -20 to 60C where lithium cells are often capped at 45C to prevent damage).
Charging times: sodium ion can charge between 2C and 3C while lithium ion is recommended to charge <1C. There are a ton of methods to get around that, but those would likely also apply to sodium ion
It falls apart a bit more on density, voltage range, and discharge speed.
Sodium ion can also handle 8C discharge rates, but not up to 10C like lithium, due to their higher internal resistance.
The voltage swing is way larger (4V->1.5V) which isn’t a huge “problem” per-se, but not convenient as all of the current BMS chips and inverters were made for the very low voltage swing of lithium, so you will need seperate ICs or only use 50% of the capacity.
And of course the 30% less density or so.
I don’t think any of those are deal breakers for grid storage or a lot of “general use” when it will be much cheaper as it gets adopted and scaled.
So you answered your own question? Because some of that is described differently in the video.
scrubbles@poptalk.scrubbles.tech 4 days ago
I’ve been waiting for sodium for a whole home battery. Not great for cars but for homes they seem great