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Designing better batteries for electric vehicles

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Re: Designing better batteries for electric vehicles

#31

Post by sokoloff »

gameswithgo wrote: post #29
sokoloff wrote: post #27

Earlier quoted context omitted.

I've driven (and overall enjoyed) a Nissan LEAF (pure EV) for the last 6.5 years. It's true that 99/100 of trips are not an issue, because many trips are short. Back/forth to work, back/forth to lunch, back/forth to sports, back/forth to the post office or grocery store. Those quickly add up the 99% of trips (as measured by getting into the car and going somewhere). Those 1% of trips really impact your overall satisf…

You might be able to get a used Tesla by then. Shops are proliferating that can repair battery packs for way less than replacement which offsets a lot of the risk.

Tesla's got their service information and parts supply far too locked up for someone like me to ever own a used Tesla.

Could be a good option for people who prefer paying someone else to maintain their cars (which is most people, of course).

Re: Designing better batteries for electric vehicles

#32

Post by lithium_throw »

guerby wrote: post #25
lithium_throw wrote: post #17

Earlier quoted context omitted.

>For example cobalt is used for getting rid of sulfur in pretty large quantities as part of the oil refining process. I don't know why this piece of misleading information is recently circulating so much. By far the most common usage (63%, in 2020, and having grown from 20% in 2006)[1] of cobalt is for lithium battery electrodes (and that is despite the fact that EVs make up a miniscule percentage of cars on the road…

"kg per millions of litres of fuel" we consume lots of fuel, if 1kg per million liter that's between 5 and 6 thousands metric tons of cobalt per year. number two cobalt producer is russia with 6 thousand metric ton per year (first is DR Congo with 100 thousand metric ton). Also rare earth are present in fossil fuel cars (Catalytic converter amongst other pieces): https://engineering.stackexchange.com/questions/13757/…

Apparently, a typical EV battery contains 0.13kg cobalt per kwh. That's 13kg cobalt in a 100kwh battery.

Over ten years, I might drive 100,000 miles, using 12,500 litres of petrol. That's 13g cobalt, in the form of sulphur-removing catalyst.

Very obviously, widespread adoption of EVs is going to cause a tremendous increase in the demand for cobalt.

You don't do EV advocacy a favour when you try to distract from these things.

Re: Designing better batteries for electric vehicles

#33

Post by lithium_throw »

jillesvangurp wrote: post #22
lithium_throw wrote: post #17

Earlier quoted context omitted.

>For example cobalt is used for getting rid of sulfur in pretty large quantities as part of the oil refining process. I don't know why this piece of misleading information is recently circulating so much. By far the most common usage (63%, in 2020, and having grown from 20% in 2006)[1] of cobalt is for lithium battery electrodes (and that is despite the fact that EVs make up a miniscule percentage of cars on the road…

It's not nothing; so it isn't misinformation. Also there are many other rare earths used for cars of course. The point here is that ICE proponents get all green and hippy like when it comes to EVs but are not willing to talk rare earth sourcing when it comes to ICE engines, fuel production, etc. It's called selective bias. The reality is that ICE vehicles contain a wide variety of materials. Ice vehicle recycling is…

>It's not nothing; so it isn't misinformation.

I could nitpick over your definition of "a very large amount of cobalt is used in petroleum refining", but the fact that an EV owner creates orders of magnitude more demand for cobalt than an ICE car owner speaks for itself.

>Ice vehicle recycling is mostly focused on extracting steel and aluminium however.

What other rare earths are present in an ICE car's engine? They are almost entirely comprised of alu and steel, which is why recycling them is so easy. Platinum is also very widely extracted from old catalytic converters.

Obviously modern cars also include a huge amount of (almost entirely un-necessary) electronics, but if you want to start talking about that, then we'll also have to include all of the other (almost entirely un-necessary) electronics we own.

Nice article on Tesla and battery recycling. Exactly which part supports your previous assertion that "Tesla recycles all of its batteries"?

>You need economies of scale for battery recycling to become more significant.

I get a feeling we'll be hearing this line for a long time.

Re: Designing better batteries for electric vehicles

#34

Post by guerby »

lithium_throw wrote: post #32
guerby wrote: post #25

Earlier quoted context omitted.

"kg per millions of litres of fuel" we consume lots of fuel, if 1kg per million liter that's between 5 and 6 thousands metric tons of cobalt per year. number two cobalt producer is russia with 6 thousand metric ton per year (first is DR Congo with 100 thousand metric ton). Also rare earth are present in fossil fuel cars (Catalytic converter amongst other pieces): https://engineering.stackexchange.com/questions/13757/…

Apparently, a typical EV battery contains 0.13kg cobalt per kwh. That's 13kg cobalt in a 100kwh battery. Over ten years, I might drive 100,000 miles, using 12,500 litres of petrol. That's 13g cobalt, in the form of sulphur-removing catalyst. Very obviously, widespread adoption of EVs is going to cause a tremendous increase in the demand for cobalt. You don't do EV advocacy a favour when you try to distract from these…

I did the computation because I just learned about this cobalt use for fossil cars (thanks to HN !) and wanted to check if it was significant or not.

On your comment:

- Cobalt (and CO2 and other chemicals) from fossil car is lost as pollution, cobalt from car batteries will be recycled (cheaper than mining) - even if recycling losses will likely be near in magnitude to fossil losses in the case of Cobalt.

- Typical EV batteries are not 100 kWh

- Tesla Model 3 SR+ MIC have 0 cobalt since use LFP chemistry. Tesla said it will use LFP for all entry level cars in the near future, and no longer use cobalt

- You didn't address the point about rare earth media coverage for fossil cars vs EV

My take on the last one: given that the company currently owning 75% of the BEV market in the USA doesn't pay mass media for advertisement at all, given that fossil car maker spend lots and lots of money for advertisement (in the 10% of car value range), mass media has massive incentives to paint EV in a negative way and it what's they're doing since the beginning.

Re: Designing better batteries for electric vehicles

#35

Post by lithium_throw »

guerby wrote: post #34
lithium_throw wrote: post #32

Earlier quoted context omitted.

Apparently, a typical EV battery contains 0.13kg cobalt per kwh. That's 13kg cobalt in a 100kwh battery. Over ten years, I might drive 100,000 miles, using 12,500 litres of petrol. That's 13g cobalt, in the form of sulphur-removing catalyst. Very obviously, widespread adoption of EVs is going to cause a tremendous increase in the demand for cobalt. You don't do EV advocacy a favour when you try to distract from these…

I did the computation because I just learned about this cobalt use for fossil cars (thanks to HN !) and wanted to check if it was significant or not. On your comment: - Cobalt (and CO2 and other chemicals) from fossil car is lost as pollution, cobalt from car batteries will be recycled (cheaper than mining) - even if recycling losses will likely be near in magnitude to fossil losses in the case of Cobalt. - Typical E…

Sure, cobalt can be recycled from EV batteries (it's one of the few things that is currently economical to extract, and even then, only if the batteries are essentially incinerated first). At around 98% recovery, that means you'd lose about as much cobalt as an ICE-driving person would consume over that same period. However, it doesn't help the fact that every EV currently needs around 10kg of the stuff in the first place, so that all has to come from somewhere.

>Typical EV batteries are not 100 kWh

For these order-of-magnitude calculations, it doesn't matter if we're talking about a 100kwh battery or a 75kwh battery.

>Tesla Model 3 SR+ MIC have 0 cobalt since use LFP chemistry.

LFP might have some nice properties, but it has around 2/3rds the energy density, and poor temperature performance. I'm sure you'll tell me "it'll get better", but then it looks to me like we're going to continue buying many generations of EVs with the promise that "the next one will fix everything!".

>You didn't address the point about rare earth media coverage for fossil cars vs EV

Why is that an issue? ICE cars don't use much in the way of rare earths, and certainly not until de-sulphurisation became a thing (which is predominately for diesel, anyway), and catalytic converters became mandated.

Once we're done talking about cobalt, we can move on to all the rare earths in an EV's traction motor...

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