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Disrupting Li-ion has to do with disrupting the high energy density + high power + high round trip efficiency use cases that it currently dominates. Much of th

by danans 4y ago

Disrupting Li-ion has to do with disrupting the high energy density + high power + high round trip efficiency use cases that it currently dominates. Much of these are existing use cases, like personal electronics and cars. The leading horse there is sodium ion last I checked. But there are many emerging energy storage use cases for which lithium ion was never a real contender. Trading off those constraints gets you options like cheap long term energy storage (metal air batteries, flow batteries, heat batteries), or batteries for lower performance vehicles or stationary storage (lithium iron phosphate).

sroussey 4y ago
You get 2-4x the energy density with aluminum over lithium. But the tech needs a decade and lithium will keep getting better.
jacquesm 4y ago
Those are all important but degradation is very important as well and a limiting factor in many use cases, as well as low temperature performance and safety.
- danans 4y ago
  LiFePo handle temperature extremes much better than Li-ion, have many times the cycle life, and can be more deeply discharged and charged. The downside is the increased weight.
  - jacquesm 4y ago
    Indeed they do. My personal favorite is Lithium-Titanate but they are still a bit expensive. https://en.wikipedia.org/wiki/Lithium-titanate_battery https://en.wikipedia.org/wiki/Lithium-titanate_battery These are not very good for mobile applications such as vehicles due to the lower energy density but for stationary applications they hold a lot of promise and they are in production already. The volume is still too low though, once that goes up this will be a serious contender for things like home batteries. They have some really interesting properties, one of which is a very long predicted life span (30 years!!).
    - danans 4y ago
      Nifty chemistry. It seems to have half the energy density of LiFePo4, but double the lifespan. Titanium seems like an expensive cathode material though. Their other standout property seems to be fast charging, which alas would be most useful in vehicles.
      - jacquesm 4y ago
        Quite interesting indeed. For RVs they are already used, but not so much in regular EVs for obvious reasons. The perfect battery will probably never become a reality, but the incremental changes may get us specialist solutions that are good enough for all practical applications. Titanium isn't all that expensive in raw form, it's when you start machining it that it gets expensive quickly. Typically it's about 1.5 times whatever the going rate for Aluminum is.

by danans 4y ago

sroussey 4y ago

You get 2-4x the energy density with aluminum over lithium. But the tech needs a decade and lithium will keep getting better.

jacquesm 4y ago

Those are all important but degradation is very important as well and a limiting factor in many use cases, as well as low temperature performance and safety.

danans 4y ago
LiFePo handle temperature extremes much better than Li-ion, have many times the cycle life, and can be more deeply discharged and charged. The downside is the increased weight.
- jacquesm 4y ago
  Indeed they do. My personal favorite is Lithium-Titanate but they are still a bit expensive. https://en.wikipedia.org/wiki/Lithium-titanate_battery https://en.wikipedia.org/wiki/Lithium-titanate_battery These are not very good for mobile applications such as vehicles due to the lower energy density but for stationary applications they hold a lot of promise and they are in production already. The volume is still too low though, once that goes up this will be a serious contender for things like home batteries. They have some really interesting properties, one of which is a very long predicted life span (30 years!!).
  - danans 4y ago
    Nifty chemistry. It seems to have half the energy density of LiFePo4, but double the lifespan. Titanium seems like an expensive cathode material though. Their other standout property seems to be fast charging, which alas would be most useful in vehicles.
    - jacquesm 4y ago
      Quite interesting indeed. For RVs they are already used, but not so much in regular EVs for obvious reasons. The perfect battery will probably never become a reality, but the incremental changes may get us specialist solutions that are good enough for all practical applications. Titanium isn't all that expensive in raw form, it's when you start machining it that it gets expensive quickly. Typically it's about 1.5 times whatever the going rate for Aluminum is.