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Some applications still require higher energy densities than what LFP can provide. Are you saying silicon anodes are more promising than solid state for those a

Some applications still require higher energy densities than what LFP can provide. Are you saying silicon anodes are more promising than solid state for those applications?

Tade0 4y ago
My position is as follows: -LFP wins on price where it fits the use case, so grid storage, current-gen EVs. -Silicon anode competes for market share with solid-state in areas where LFP can't, namely aerospace and next-gen EVs or even aviation, should they ever reach 1kWh/kg. The former has easily a decade lead considering that they're already selling packs and the latter exists largely in the lab or on paper. I also believe even 400Wh/kg at pack level is already good enough to be a serious proposition as replacement for internal combustion in land transportation, provided pricing is adequate.
- ngrilly 4y ago
  I totally agree with your position on LFP, and about 400 Wh/kg being enough to unlock some applications. But I’m not fully convinced on silicon anodes versus solid state. Yes, energy density is very promising, but I understand capacity fade is still a huge problem due to silicon volume expansion/reduction while charging/discharging?
  - naasking 4y ago
    Is there still a fire risk with LFP? From my understanding, solid state batteries have a large safety advantage here because of this.
    - Tade0 4y ago
      Yes - LFP still uses a flammable, liquid electrolyte - usually ethylene carbonate. That being said LFP survives the nail penetration test without causing a fire, so it's considerably safer than the usual alternatives.
  - Tade0 4y ago
    That's the problem they've solved here using nanowires - the cells have a 200-1200 cycle life depending on operating conditions - I suppose the range is so wide because of the temperature range - -30°C - 55°C. It's not surprising to see cells degrade fast at the hotter end of this spectrum. For EVs they advertise cells with no less than 410Wh/L, 4C rate of discharge.
panick21_ 4y ago
LFP cathodes and silicon or 'solid state' aka lithium metal anodes are not incompatible.

Some applications still require higher energy densities than what LFP can provide. Are you saying silicon anodes are more promising than solid state for those applications?

Tade0 4y ago

My position is as follows: -LFP wins on price where it fits the use case, so grid storage, current-gen EVs. -Silicon anode competes for market share with solid-state in areas where LFP can't, namely aerospace and next-gen EVs or even aviation, should they ever reach 1kWh/kg. The former has easily a decade lead considering that they're already selling packs and the latter exists largely in the lab or on paper. I also believe even 400Wh/kg at pack level is already good enough to be a serious proposition as replacement for internal combustion in land transportation, provided pricing is adequate.

ngrilly 4y ago
I totally agree with your position on LFP, and about 400 Wh/kg being enough to unlock some applications. But I’m not fully convinced on silicon anodes versus solid state. Yes, energy density is very promising, but I understand capacity fade is still a huge problem due to silicon volume expansion/reduction while charging/discharging?
- naasking 4y ago
  Is there still a fire risk with LFP? From my understanding, solid state batteries have a large safety advantage here because of this.
  - Tade0 4y ago
    Yes - LFP still uses a flammable, liquid electrolyte - usually ethylene carbonate. That being said LFP survives the nail penetration test without causing a fire, so it's considerably safer than the usual alternatives.
- Tade0 4y ago
  That's the problem they've solved here using nanowires - the cells have a 200-1200 cycle life depending on operating conditions - I suppose the range is so wide because of the temperature range - -30°C - 55°C. It's not surprising to see cells degrade fast at the hotter end of this spectrum. For EVs they advertise cells with no less than 410Wh/L, 4C rate of discharge.

panick21_ 4y ago

LFP cathodes and silicon or 'solid state' aka lithium metal anodes are not incompatible.