3 ms·

90 Wh/kg is actually a pretty decent energy density (LiPo batteries are now approaching 200 Wh/kg, but less combustible LiFe chemistries are around 100 Wh/kg).

by lhl 11y ago

90 Wh/kg is actually a pretty decent energy density (LiPo batteries are now approaching 200 Wh/kg, but less combustible LiFe chemistries are around 100 Wh/kg). Does anyone know if there's any information on how the stability/thermal characteristics of the sodium-ion compares?

lhl 11y ago
Just to follow up, since I was curious to do a bit of searching: * Wikipedia's article [1] mentions two other startups working on sodium-ion batteries. Faradion apparently has a 150 Wh/kg sodium-ion battery [2]. According to the Wikipedia article, "These cells can be completely drained (to zero charge) without damaging the active materials. They can be stored and shipped safely." * A Physics Today article entitled "Surprising stability for sodium-ion batteries" [3] summarizes a Brookhaven National Laboratory that despite an expected worse performance for Na vs Li, (with a tin anode), they found that "after that initial damage, subsequent desodiation and nine further charging–discharging cycles produced no further fractures: The expansion and shrinkage were reversible and produced a minimal decrease in charge capacity." * While searching I found an interesting paper on a NA-SO2 formulation "A room-temperature sodium rechargeable battery using an SO2-based nonflammable inorganic liquid catholyte" [4] which has great numbers (discharge capacity similar to LiFe), but seems like one of those battery formulations that never make it out into the real world. That's as far as my passing curiousity took it, but if anyone works in the field, it'd be interesting to hear their thoughts. [1] https://en.wikipedia.org/wiki/Sodium-ion_battery https://en.wikipedia.org/wiki/Sodium-ion_battery [2] http://cen.acs.org/articles/93/i29/Challenging-Lithium-Ion-Batteries-New.html http://cen.acs.org/articles/93/i29/Challenging-Lithium-Ion-B... [3] http://scitation.aip.org/content/aip/magazine/physicstoday/news/10.1063/PT.5.7184 http://scitation.aip.org/content/aip/magazine/physicstoday/n... [4] http://www.ncbi.nlm.nih.gov/pmc/articles/PMC4525335/ http://www.ncbi.nlm.nih.gov/pmc/articles/PMC4525335/

by lhl 11y ago

lhl 11y ago

Just to follow up, since I was curious to do a bit of searching: * Wikipedia's article [1] mentions two other startups working on sodium-ion batteries. Faradion apparently has a 150 Wh/kg sodium-ion battery [2]. According to the Wikipedia article, "These cells can be completely drained (to zero charge) without damaging the active materials. They can be stored and shipped safely." * A Physics Today article entitled "Surprising stability for sodium-ion batteries" [3] summarizes a Brookhaven National Laboratory that despite an expected worse performance for Na vs Li, (with a tin anode), they found that "after that initial damage, subsequent desodiation and nine further charging–discharging cycles produced no further fractures: The expansion and shrinkage were reversible and produced a minimal decrease in charge capacity." * While searching I found an interesting paper on a NA-SO2 formulation "A room-temperature sodium rechargeable battery using an SO2-based nonflammable inorganic liquid catholyte" [4] which has great numbers (discharge capacity similar to LiFe), but seems like one of those battery formulations that never make it out into the real world. That's as far as my passing curiousity took it, but if anyone works in the field, it'd be interesting to hear their thoughts. [1] https://en.wikipedia.org/wiki/Sodium-ion_battery https://en.wikipedia.org/wiki/Sodium-ion_battery [2] http://cen.acs.org/articles/93/i29/Challenging-Lithium-Ion-Batteries-New.html http://cen.acs.org/articles/93/i29/Challenging-Lithium-Ion-B... [3] http://scitation.aip.org/content/aip/magazine/physicstoday/news/10.1063/PT.5.7184 http://scitation.aip.org/content/aip/magazine/physicstoday/n... [4] http://www.ncbi.nlm.nih.gov/pmc/articles/PMC4525335/ http://www.ncbi.nlm.nih.gov/pmc/articles/PMC4525335/