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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

#181

Post by simplotek »

satiric wrote: post #164
subarctic wrote: post #136

Earlier quoted context omitted.

>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.

Still, I'm not sure OP's train of thought holds. Mass matters because you need to spend energy to accelerate it and move it uphill. Regenerative breaking does not have 100% efficiency. Therefore, energy losses are proportional to weight. Also, isn't tire drag proportional to weight? That's a energy sink that can't be recovered by breaking.

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

#182

Post by [deleted] »

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.

[deleted]

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

#183

Post by rbanffy »

briffle wrote: post #104
rbanffy wrote: post #94

Earlier quoted context omitted.

> For example, a Chevy Bolt has a lithium ion battery to power the drivetrain and a conventional lead-acid battery for the accessories. This seems like an odd choice - unless you already bought a supply of lead-acid batteries for the next 50 years or so. I've read about a car using supercapacitors in the regenerative brakes to capture energy at high current and, then let it trickle back into the main batteries (or dr…

It could be great if you were a car manufacturer that already had an existing, very large supply chain for lights, dashboard, powered window motors, and other accessories, that were already 12 volt.

But unless you have a already contracted lifetime supply of lead-acid batteries, a buck converter is much cheaper, and lighter.

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

#184

Post by rbanffy »

robocat wrote: post #177
dreamcompiler wrote: post #171

Earlier quoted context omitted.

This was the best news I heard at Tesla investor day. It should simplify and cut the cost of the in-cabin wiring. When Sandy Munro interviewed Elon Musk a couple of years ago he said "Why are you still using 12v stuff in the cabin?" Musk's answer was that the automotive supply chain was entirely geared around 12v equipment and they had to take advantage of that to get to market quickly. I'm glad those days are almost…

Isn’t there a whole trucking supply chain geared around 24 Volts?

All it'd take is a middle terminal in a 24V battery to make it a 12/24V one.

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

#185

Post by rbanffy »

xxs wrote: post #103
rbanffy wrote: post #94

Earlier quoted context omitted.

> For example, a Chevy Bolt has a lithium ion battery to power the drivetrain and a conventional lead-acid battery for the accessories. This seems like an odd choice - unless you already bought a supply of lead-acid batteries for the next 50 years or so. I've read about a car using supercapacitors in the regenerative brakes to capture energy at high current and, then let it trickle back into the main batteries (or dr…

The 12v lane is ubiquitous, and standardized. Supercaps are inefficient when it comes to storage per weight and volume, discharge rate too. Both lead acid and supercaps are not even remotely comparable to the main liion battery, they're suppliments, and not interesting ones

The supercaps aren't for long-term storage - just long enough to allow the extra juice to flow back to the batteries. Racing cars sometimes do that with flywheels.

As for 12V, all one needs is a regulator. Unless you have a long-term supply contract (that, I bet, won't be renewed for too long), a lead-acid battery is just dead weight.

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

#186

Post by robocat »

rbanffy wrote: post #184
robocat wrote: post #177

Earlier quoted context omitted.

Isn’t there a whole trucking supply chain geared around 24 Volts?

All it'd take is a middle terminal in a 24V battery to make it a 12/24V one.

That would run the risk of unbalanced batteries. I had a small truck years ago, and everything was 24V as far as I recall.

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

#187

Post by uoaei »

mabbo wrote: post #91
uoaei wrote: post #73

Earlier quoted context omitted.

Different battery designs and chemistries are appropriate for different applications. I don't care about how much a battery weighs if it never moves, for example.

I'm of two minds on this. On the one hand, you're right that for different applications having different metrics can be acceptable. Sure, a battery for your home that never moves can be heavy and large and that's okay. But then you have to consider the economics of production. How many of those batteries will you make? What will the factory for them cost to build? And what would it cost instead to just make a bunch m…

Some of the more exotic battery designs are things like "rust powder held in a silo at a certain temperature" which presumably can be assembled on-site. It seems to me overly reductive to assume that stationary batteries will be "just mobile batteries but heavier".

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

#188

Post by entropicgravity »

PragmaticPulp wrote: post #144
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…

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.

In the not too distant future cities will ban large vehicles EV and ICE from the downtown core. The automotive market will then split into small city cars and bigger highway cars. In the city core roads will be covered (because no poisonous exhaust gases).

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

#189

Post by entropicgravity »

DennisP wrote: post #114
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.…

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.

These batteries will target the aviation market which will be willing to pay much more than the automotive segment. EV's need a certain weight for safety and once a battery pack goes lower than that weight the incentive for buying lighter batteries quickly fades.

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

#190

Post by entropicgravity »

somewhat_drunk wrote: post #131
greggsy wrote: post #61

Earlier quoted context omitted.

H2 has the benefit of being much easier to store, transport and transfer than batteries. It’s able to be stored in small containers and large vessels of any shape. Batteries manufacturing is much more complex. Electricity needs to be transferred from a power station over wires, while hydrogen can be pumped into a vehicle from a bulk source. Sure H2 is dangerous, but so is LNG, and petrol for that matter. 100+ years o…

Nah. I worked as a project engineer in a hydrogen fuel cell test lab for a few years. H2 is EXTREMELY hazardous. It can be ignited by a miniscule amount of energy (i.e. a tiny static spark will do it), and it has a very fast flame front, which creates an extremely energetic explosion. It's also the smallest molecule, so it's very difficult to prevent leakage, and it embrittles and degrades most steels over time. Addi…

All true. The real reason Toyota is interested in hydrogen is that it would maintain its current balance sheet.

Hydrogen would allow Toyota to swap one messy, expensive, heavy power plant requiring lots of maintenance (ie fuel cell) for ICE technology.

Whereas EV technology has almost no maintenance, a motor with one moving part and regenerative braking that means even the brakes last forever. The accountants at Toyota would definitely frown at that.

All the other car companies did the same calculations and said 'NO'. Lets just say we'll do that and keep kicking the can down the road for as long as possible.

Now, thanks to Tesla, the cat is out of the bag and the entire industry knows they'll need a new financial platform to survive in the future and no, hydrogen will not save their sorry butts.

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