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Solid-State Battery Has 2x the Energy–and No Anode

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Re: Solid-State Battery Has 2x the Energy–and No Anode

#161

Post by jgtrosh »

lazide wrote: post #148
PragmaticPulp wrote: post #144

Earlier quoted context omitted.

Heavier cars are more dangerous in collisions. The extra weight of a big battery requires a bigger frame to carry it, bigger suspension, wider tires, and so on. I’m not really happy that some of these monster EVs are approaching 10,000lbs with fast 0-60 times. It’s like a kinetic missile that can reach a momentum capable of obliterating your average 3000lb compact car in under 5 seconds.

That is pretty much the definition of moving the goal posts?

There can be multiple reasons for heavy cars to be bad. Additionally, extra heavy cars wear roads much faster.

It's nice to have a way of recuperating energy but it doesn't solve everything.

Re: Solid-State Battery Has 2x the Energy–and No Anode

#162

Post by eknkc »

dheera wrote: post #160
mabbo wrote: post #63

Lithium ion batteries set the standard because they have an acceptable level of all the key metrics: energy storage by weight; energy storage by volume; discharge rate; charging rate; production costs. Every single one of these big breakthrough announcements touts how great this new tech is- in just one or two particular metrics. The problem is that Li-Ion batteries are just barely acceptable in all of those metrics.…

Those are only a few metrics. Li-ion is not fantastic in (a) charging cycles and battery depletion or (b) fire safety. It also depends a lot on use case; for example, for home electricity storage (like a PowerWall) I would gladly give up energy density for safety. If there's some battery tech that can handle 50000 charge cycles and completely non-flammable but weighs 100 tons and has 10% of the energy density of Lith…

I guess LTO is right there at the moment. Even LiFePo4 batteries are a lot more safer than Li-Ion ones. From what I’ve seen, I would gladly have a LTO pack in my house.

Re: Solid-State Battery Has 2x the Energy–and No Anode

#163

Post by DennisP »

panick21_ wrote: post #150
DennisP wrote: post #114

Earlier quoted context omitted.

Here are the specs on the Amprius silicon-anode battery, currently shipping in low volume: https://amprius.com/products/ That's better on all the metrics you listed except cost, which it doesn't mention. Whatever their current cost is, it should drop significantly once they complete their factory in 2025. https://amprius.com/facility/ Most of the battery is standard lithium-ion, the anode is a drop-in replacement.

Amprius technology will not magically drop in price as much as people think. Some manufacturing methods don't just scale and become cheap. Their large facility planned is still tiny in terms of battery factories. This will remain an expensive niche product.

No small company is going to suddenly build a gigafactory. But 5GWh, if they manage it, is not that small. One of Tesla's gigafactories is 37GWh.

Re: Solid-State Battery Has 2x the Energy–and No Anode

#164

Post by satiric »

subarctic wrote: post #136
phkahler wrote: post #127

Earlier quoted context omitted.

Actually, energy storage by weight is not as big a deal for electric cars. Regenerative braking can recover most of a vehicles kinetic energy, which is where the weight dependent energy goes. This is why several hybrids get better fuel economy in city driving than highway, the biggest losses are due to aero which increases nonlinearly with speed. Otherwise yes, it's important to find something better without sacrific…

>Regenerative braking can recover most of a vehicles kinetic energy I used to think that was the case, but then i think i read somewhere that it only recovers 20% of the kinetic energy. Can't find it anymore though

It depends a lot on how you drive. If you do a lot of hard braking, the car will have to use a lot of friction braking. If you slow down more gradually, the car can just use regen which is gonna be pretty efficient.

Re: Solid-State Battery Has 2x the Energy–and No Anode

#165

Post by _a_a_a_ »

jgtrosh wrote: post #161
lazide wrote: post #148

Earlier quoted context omitted.

That is pretty much the definition of moving the goal posts?

There can be multiple reasons for heavy cars to be bad. Additionally, extra heavy cars wear roads much faster. It's nice to have a way of recuperating energy but it doesn't solve everything.

They didn't say it solved everything

Re: Solid-State Battery Has 2x the Energy–and No Anode

#166

Post by brightball »

mabbo wrote: post #63

Lithium ion batteries set the standard because they have an acceptable level of all the key metrics: energy storage by weight; energy storage by volume; discharge rate; charging rate; production costs. Every single one of these big breakthrough announcements touts how great this new tech is- in just one or two particular metrics. The problem is that Li-Ion batteries are just barely acceptable in all of those metrics.…

The only one that I'm actively monitoring is this one because it handles the other metrics AND gives a path forward to rapid charging, which is the core requirement to displace liquid fuels. IMO any battery advance that doesn't address rapid charging is going to fall to the wayside for exactly the reason you stated.

https://www.forbes.com/sites/michaeltaylor/2021/05/13/ev-ran...

Re: Solid-State Battery Has 2x the Energy–and No Anode

#167

Post by megaman821 »

dheera wrote: post #160
mabbo wrote: post #63

Lithium ion batteries set the standard because they have an acceptable level of all the key metrics: energy storage by weight; energy storage by volume; discharge rate; charging rate; production costs. Every single one of these big breakthrough announcements touts how great this new tech is- in just one or two particular metrics. The problem is that Li-Ion batteries are just barely acceptable in all of those metrics.…

Those are only a few metrics. Li-ion is not fantastic in (a) charging cycles and battery depletion or (b) fire safety. It also depends a lot on use case; for example, for home electricity storage (like a PowerWall) I would gladly give up energy density for safety. If there's some battery tech that can handle 50000 charge cycles and completely non-flammable but weighs 100 tons and has 10% of the energy density of Lith…

How often will you fully cycle a home battery? At 100 cycles a year it would take 50 years to deplete a 5,000 cycle battery down to 80%. Another 50 years before it was 50%. There is no way the casing would be fully intact and the electronics even be functioning after that long.

Current LFP batteries should last multiple decades as a home battery. The already have low flammability. The price is getting more affordable. They could just be part standard of a home electric system in a decade or two, like a whole-home surge protector.

Re: Solid-State Battery Has 2x the Energy–and No Anode

#168

Post by cptskippy »

Tagbert wrote: post #133
mabbo wrote: post #63

Lithium ion batteries set the standard because they have an acceptable level of all the key metrics: energy storage by weight; energy storage by volume; discharge rate; charging rate; production costs. Every single one of these big breakthrough announcements touts how great this new tech is- in just one or two particular metrics. The problem is that Li-Ion batteries are just barely acceptable in all of those metrics.…

Lithium ion batteries are not a single technology and are not static. There are periodic changes that improve the batteries in various dimensions. They are constantly evolving. At the same time, it is perfectly feasible for EVs to switch to alternate chemistries a construction methods. Individual vehicles might not switch but a manufacturer could switch their product line to start using sodium or sulphur or whatever…

You're right and so is the OP.

Lithium based batteries of varying chemistries collectively in space that few other battery chemistries overlap.

Re: Solid-State Battery Has 2x the Energy–and No Anode

#169

Post by meatmanek »

AlotOfReading wrote: post #145
newZWhoDis wrote: post #137

Earlier quoted context omitted.

> increased danger to pedestrians and cyclists, etc. Why do seemingly so people here understand clipping functions? The lethality of a pedestrian-vehicle collision with a 4,000lb vehicle at 60MPH and a 400,000lb vehicle at 60MPH are both 1 In practical terms, the additional weight of an EV has zero effect on pedestrian collision lethality, whereas something like bumper design would.

I'm not sure why clipping functions are relevant, because the probability of death isn't 100% even for semis hitting pedestrians at highway speeds. It's actually more like 80-90%. There's still quite a bit of long tail for higher speeds beyond that as well. SUVs and other "heavy" consumer vehicles are somewhere in the 75% range at comparable speeds, while sedans are down around 65% mortality. Feel free to find your o…

Vehicle mass matters a lot in vehicle-to-vehicle collisions, where the energy and momentum of each vehicle is going to change a lot, but when a car collides with a person, the car's momentum is barely affected, because the car is already significantly more massive than the person. A 20x mass ratio is already practically infinite.

In a direct collision between a moving 1000kg car going 10 m/s and a stationary 50kg person, the person will end up moving somewhere between 9.5 m/s (perfectly inelastic collision) and 19.05 m/s (perfectly elastic). The car will end up moving 9.5 m/s (perfectly inelastic) and 9.05 m/s (perfectly elastic).

In a direct collision between a moving 10000kg car going 10 m/s and a stationary 50kg person, the person will end up moving 9.95 m/s (perfectly inelastic) and 19.90 m/s (perfectly elastic). The car will end up moving somewhere between 9.95 m/s (perfectly inelastic) and 9.90 m/s (perfectly elastic).

Even though we 10x'd the weight of the car, we only increased the velocity of the person after impact by about 5%, and energy imparted on the person by about 10%.

I suspect vehicle size (or rather, the size/shape of the front of the vehicle) has way more effect on pedestrian survivability than the weight of the vehicle. SUVs and trucks will impart the force of impact directly to your torso and head, and then subsequently run you over. Sedans hit you in the legs and then roll you over the top of the vehicle.

Re: Solid-State Battery Has 2x the Energy–and No Anode

#170

Post by GaryNumanVevo »

newZWhoDis wrote: post #137
jackmott42 wrote: post #41

Earlier quoted context omitted.

EVs are already very heavy, and when the model 3 switched to LFP it got even heavier. This mass has lots of subtle consequences that aren't always appreciated. Like accelerated tire wear (which Tesla owners notice after they buy) and increased particulate pollution from that, increased road wear, increased danger to pedestrians and cyclists, etc. So, I'm less excited about LFP. There are a number of ideas in the work…

> increased danger to pedestrians and cyclists, etc. Why do seemingly so people here understand clipping functions? The lethality of a pedestrian-vehicle collision with a 4,000lb vehicle at 60MPH and a 400,000lb vehicle at 60MPH are both 1 In practical terms, the additional weight of an EV has zero effect on pedestrian collision lethality, whereas something like bumper design would.

Higher curb weight correlates with longer breaking distances
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