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Extremely. Tesla batteries require some disassembly effort, and the model 3 makes recycling trickier because the cells are potted in plastic, but the actual ce

Extremely. Tesla batteries require some disassembly effort, and the model 3 makes recycling trickier because the cells are potted in plastic, but the actual cells of any li ion battery are eminently recyclable. The process involves shredding or incinerating the cells first, then dumping the results in an electrolysis tank. Because the cells are essentially just chunks of plastic, aluminum, copper (and steel for teslas) and various powders, the large chunks can be easily sorted from the anode and cathode material by washing. The powder goes into an electrolysis bath, which extracts the high-value metals (cobalt and nickel) to a pretty good purity. The carbon leftovers (anode, electrolyte, and plastics) collect at the bottom with the lithium and leftover cathode material (aluminum, silicon, other things depending on the chemistry). The leftovers are mostly sold as clinker. You could extract the lithium from that, but at present it's not done. For one thing, batteries actually have a lower concentration of lithium than lithium brine and even some lithium-bearing ores. Recycling is also just so low-volume that if you did extract the lithium you wouldn't really have enough to be worth selling. Regardless, the clinker material is ecologically inert. Nickel and cobalt are the only hazardous materials in the battery. Everything else is extremely common in nature- lithium is present in every water supply since it's a natural component of salt. Carbon is obviously everywhere, even in elemental forms. Any rock you pick up almost anywhere in the world is overwhelmingly likely to be primarily made of silicon. Aluminum is similar. NB that all the clinker materials will be in oxide or hydroxide forms.

mrfusion 8y ago
Another option is to simply repurpose old batteries to stationary storage applications. Even if it’s only holding a five percent charge, who cares if they’re just sitting in a building somewhere.
- snowwindwaves 8y ago
  Because they take up space and space in a building isn't free. Nor is the equipment to use the batteries as storage
  - JoeAltmaier 8y ago
    Nor is the electricity lost due to heating the inefficient battery. Old batteries also get hot, as their cathode(?) breaks down
    - hwillis 8y ago
      This is incorrect; the cathode only breaks down during a fire or something catostrauphic. Li ion develops higher internal resistance due to SEI buildup, which is less plastic and causes voltage sag as ions migrate. However this effect is cubic (iirc, cant look it up on the throne) so at low draw its heavily reduced. What is low draw depends very heavily on the chemistry, but at <1 C most batteries are only a couple percent less efficient. Every other energy storage method including hydraulic is far less efficient.
- hwillis 8y ago
  Yep! Old batteries tend to still hold a charge quite well- they become less efficient under the same load, which gives the impression that they lose capacity much faster than is actually the case. If you derate them they perform quite well- a battery may last 60% as long as it did originally, but when used more slowly it will hold more like 80% of its original capacity. In fact, battery degradation has in some cases been slower than battery innovation! Batteries have gotten better so quickly that the newer ones may have 50% more capacity even if the old ones didnt degrade much at all. Edit: its also complicated by the multitude of batteries and chemistries. Li ion is incredibly diverse compared to other battery families, and the various types can't be used together. Practically speaking you can only reuse batteries of a single chemistry and form factor, and the chemistry changes every few years or less. Its just not a stable enough industry for that yet.
- WorldMaker 8y ago
  Arguably that's a reason for Tesla's PowerWall project, to secondary use old car batteries as additional source for PowerWall. Interestingly, Nissan has a PowerWall-like project of their own, but only for secondary use batteries (as they want to prioritize car production, being you know a car company). You don't hear it advertised because Nissan has seen a far slower trickle of secondary use batteries than they originally expected to see, and thus have had very few of their PowerWall-like systems to sell to any market.
oblio 8y ago
> lithium is present in every water supply since it's a natural component of salt I guess you mean salts in general, otherwise NaCl has no Li(thium) in sight :)
- hwillis 8y ago
  "table salt" is pretty much just NaCl, but no I don't mean salts in the general chemical sense. I mean salt- the kind in all water and the prehistoric stuff that is mined. That kind of salt is a big ol' mix that is primarily NaCl but has nontrivial amounts of lithium, potassium and magnesium compounds as well. Lithium salts in particular are more common in freshwater than other kinds of salt, due to various geological properties that I dont really know much about.
gandreani 8y ago
That's neat! Where did you learn this?
- hwillis 8y ago
  Academic papers, press releases, a habit of closely following batteries for many years, and chemistry and engineering in school. Batteries are fascinating!
olivermarks 8y ago
thank you @hwillis
ant6n 8y ago
> Everything else is extremely common in nature- lithium is present in every water supply since it's a natural component of salt. Carbon is obviously everywhere, even in elemental forms. The problem with carbon is not the element, but the molecules. Plastic is largely made of carbon, but doesn't belong in nature.
- hwillis 8y ago
  The "pyrolytic" (incineration + electrolysis) process just leaves elemental carbon. Shredding obviously varies. I believe the plastics are usually burnt, but I'm not sure what happens to the other carbon compounds- they're fairly simple things (eg ethylene carbonate and dimethyl carbonate), both of which break down in nature relatively quickly. I'm not sure what the timeline on biodegradeability is, but for comparison ethylene glycol (which is a bit simpler, but similar) breaks down in ten days according to wikipedia. It seems to me like it'd be easier to burn them off rather than skimming them after electrolysis, but I don't want to assume.

mrfusion 8y ago

Another option is to simply repurpose old batteries to stationary storage applications. Even if it’s only holding a five percent charge, who cares if they’re just sitting in a building somewhere.

snowwindwaves 8y ago
Because they take up space and space in a building isn't free. Nor is the equipment to use the batteries as storage
- JoeAltmaier 8y ago
  Nor is the electricity lost due to heating the inefficient battery. Old batteries also get hot, as their cathode(?) breaks down
  - hwillis 8y ago
    This is incorrect; the cathode only breaks down during a fire or something catostrauphic. Li ion develops higher internal resistance due to SEI buildup, which is less plastic and causes voltage sag as ions migrate. However this effect is cubic (iirc, cant look it up on the throne) so at low draw its heavily reduced. What is low draw depends very heavily on the chemistry, but at <1 C most batteries are only a couple percent less efficient. Every other energy storage method including hydraulic is far less efficient.
hwillis 8y ago
Yep! Old batteries tend to still hold a charge quite well- they become less efficient under the same load, which gives the impression that they lose capacity much faster than is actually the case. If you derate them they perform quite well- a battery may last 60% as long as it did originally, but when used more slowly it will hold more like 80% of its original capacity. In fact, battery degradation has in some cases been slower than battery innovation! Batteries have gotten better so quickly that the newer ones may have 50% more capacity even if the old ones didnt degrade much at all. Edit: its also complicated by the multitude of batteries and chemistries. Li ion is incredibly diverse compared to other battery families, and the various types can't be used together. Practically speaking you can only reuse batteries of a single chemistry and form factor, and the chemistry changes every few years or less. Its just not a stable enough industry for that yet.
WorldMaker 8y ago
Arguably that's a reason for Tesla's PowerWall project, to secondary use old car batteries as additional source for PowerWall. Interestingly, Nissan has a PowerWall-like project of their own, but only for secondary use batteries (as they want to prioritize car production, being you know a car company). You don't hear it advertised because Nissan has seen a far slower trickle of secondary use batteries than they originally expected to see, and thus have had very few of their PowerWall-like systems to sell to any market.

oblio 8y ago

> lithium is present in every water supply since it's a natural component of salt I guess you mean salts in general, otherwise NaCl has no Li(thium) in sight :)

hwillis 8y ago
"table salt" is pretty much just NaCl, but no I don't mean salts in the general chemical sense. I mean salt- the kind in all water and the prehistoric stuff that is mined. That kind of salt is a big ol' mix that is primarily NaCl but has nontrivial amounts of lithium, potassium and magnesium compounds as well. Lithium salts in particular are more common in freshwater than other kinds of salt, due to various geological properties that I dont really know much about.

gandreani 8y ago

That's neat! Where did you learn this?

hwillis 8y ago
Academic papers, press releases, a habit of closely following batteries for many years, and chemistry and engineering in school. Batteries are fascinating!

olivermarks 8y ago

thank you @hwillis

ant6n 8y ago

> Everything else is extremely common in nature- lithium is present in every water supply since it's a natural component of salt. Carbon is obviously everywhere, even in elemental forms. The problem with carbon is not the element, but the molecules. Plastic is largely made of carbon, but doesn't belong in nature.

hwillis 8y ago
The "pyrolytic" (incineration + electrolysis) process just leaves elemental carbon. Shredding obviously varies. I believe the plastics are usually burnt, but I'm not sure what happens to the other carbon compounds- they're fairly simple things (eg ethylene carbonate and dimethyl carbonate), both of which break down in nature relatively quickly. I'm not sure what the timeline on biodegradeability is, but for comparison ethylene glycol (which is a bit simpler, but similar) breaks down in ten days according to wikipedia. It seems to me like it'd be easier to burn them off rather than skimming them after electrolysis, but I don't want to assume.