Solid state batteries come in several flavours. Most of them don't stop dendrites.
The flavour you want is polymer, single ion conducting solid state with an ion transport activation energy below 10kJ/mol at room temperature and no phase transitions from -40C to 80C.
> The flavour you want is polymer, single ion conducting solid state with an ion transport activation energy below 10kJ/mol at room temperature and no phase transitions from -40C to 80C.
what makes it so? I don't know anything about this subject, I'm really curious now about what the perfect battery would be.
No idea why polymer single ion conducting would stop dendrites (I know people are looking for it, I don't know why).
But 10kJ/mol of activation energy is another way of saying less than 100mV of internal loses, and avoiding phase transitions means that your battery won't stop working on that temperature range.
The only thing different from this list is the ceramic separator. It’s not polymer. However, the ceramic is ultra thin to the point that it’s flexible so volume expansion isn’t a problem and it solves the dendrite problem.
Perhaps a polymer will be invented that can’t be pierced by dendrites. But existing polymers need to be heated for ion transfer efficiency and are combustable.
Technically, QuantumScape also uses an organic liquid catholyte inside the cathode. So it’s not “pure” solid state.
Well that's fine for terrestrial use but aerospace needs that range to be expanded a little in both directions, otherwise it won't be much of a holy grail if it won't cover the needs of one of the largest growing industries.
If you know a bit about electronics, you might be a bit surprised by the term 'solid-state battery'. It's a poor analogue to the more common usage of solid-state with semiconductors, integrated circuits, etc. -- a "solid-state" cell is still a chemical cell. It's not a paradigm shift on the level of, say, replacing a relay with a MOSFET.
The article gives the technical reasons that answer the headline question (e.g. potential for better energy density)
I am surprised they didn't point out the literal "killer app" - military drones. Energy density is king for any airborne power source. And dendrite growth during charge/discharge cycling isn't as big a deal for that application (how many times would you need to charge a disposable weapon?)
For disposable applications like that, aren't there single-use chemistries that are better already? I'm thinking by analogy to things like:
- WW2 proximity fuzes that had batteries where the electrolyte was in a vial that got smashed by the G-forces of being shot out of a cannon providing power to the radio inside for the 10 seconds it needs to get to the incoming aircraft
- Hearing aid Zinc-Air batteries, that are extremely energy dense because you only have to actually manufacture the anode, the cathode is the entire atmosphere of the Earth
- Missile batteries, which are often Lithium-silicon/Iron Disulfide batteries that borrow some thermal energy from the rocket motor to get a molten salt electrolyte
Less weight (all else being equal) is the same thing as more battery for drones. I.e. better range, payload mass, and/or flight time. You probably want both cheap and poor performing as well as expensive and high performing available.
I can - it’s called a bomb. Some of the problems with batteries are heat dissipation (one of those problems that superconductors would mostly solve), fire safety, and end of life disposal. Higher energy density makes it even worse.
A good place to start would be a BMS on individual cells that monitors them for general degradation, unexpected discharge, unexpected temperature changes, and can remove a failing cell from the array.
Gasoline has 10x the energy (MJ/Kg) than TNT, but it's not a "bomb". Being a "bomb" is about energy release rate. A battery is still controlled by its chemistry.
Some heavier elements have hilariously high energy densities and aren't bombs (on their own), but the catch is the energy release is a trickle. Point is it's not an automatic follow that high density = high discharge.
Tesla has been around for nearly 20 years. Model S (12 years) has gained 17% of range due to chemistry (rest is system efficiency and simply bigger battery).
I don't think 10x density is possible without getting into nuclear, at least not with the chemistries we know of today, everything at a certain point becomes an explosive.
Speaking of nuclear, getting tons of the material that powers mars rovers and putting them in every home would generate enough power for decades... At the cost of being able to build a nuclear bomb in a garage.
The next revolution will be small scale generation. Fuel cells, extremely efficient cheap solar, even smaller modular reactors, etc.
I live in western Pennsylvania and have both natural gas and electric service, a roof and 1/3 acre of land to utilize. I would love to get rid of at least one of my utility bills and I’m becoming more interested in decoupling from the electric grid than natural gas service. I dream of a future where competition comes to monopoly utilities by way of direct competition with each other as there is a not so far off future where I can utilize solar, batteries and a natural gas fuel cell to cut ties with my Electric Utility. If that kind of competition can exist then the game is on for those utilities to start fighting for customers.
I seem to remember recent advances in TMSR research and construction. Those tend to e much safer and have safer byproducts than uranium or plutonium fueled water-cooled reactors.
Agreed, but I think people can imagine and companies are very motivated: powertools, phones, laptops, watches, backup UPS, cars, hospital equipment... there's high demand for durable, long-lasting batteries. I think the research is there, it's just complex chemistry. We'll get there. Impressive to see the progress in EV batteries and they've actually turned out to be more durable than first feared.
I think, apart from finding better Batteries altoghether, we should build multi-tier batteries inspired by biology.
Humans have bloodsugar, sugar in the Liver and then fat. All of them have their respective properties with availability and amount. This way, engineering tradeoffs could be allocated much more fine grained.
For example, a while ago I read about a startup building an energy storage where they heat up large amounts of sand to store the surplus of renewables. This could serve analogous to the fat in humans.
Most of the things that we copy directly from humans do not work in terms of robustness.
Its like instead of harddrive use human DNA to store the data for 3T years,but no-one is mentioning the bandwidth speed here(which is the most important thing) etc,
I know it has some usecases.Also "one spoon butter is more energy dense than a battery"
but how we are gonna use butter(I dont know enough bio) but it is way harder to convert energy .
Humans do that because we're big and extra complicated. The closest analogue is probably a hybrid car, though ideally you'd want one that can create synthetic fuel from its battery. But I suspect cellphones are properly analogous to e.g. bacteria that have much simpler energy storage.
I think I've heard of sodium, lithium hybrids. But that's only 2, what's the fat? Gasoline, LPG hybrid? Shit gets expensive fast. Probably 2x cost of just a sodium or ion EV? The human body is too amazing.
It should be relatively straightforward to imagine — we already have that in gasoline-powered internal combustion engines.
The Watt-hours per kilogram of good Lithium Ion batteries is around 250-280 Wh/Kg; for Lithium Iron Phosphate it's about 180 Wh/kg, and for Sodium-Ion about 170 Wh/Kg.
The raw energy in gasoline is about 12,300 Wh/Kg but automobile internal combustion engines get only about 20-30% efficiency yielding about 2500-3600 Wh/Kg. For aviation piston engines it is a bit better at 25-30$ so 3000-3600 Wh/kg.
So, the batteries, instead of being 10-12X the weight of the gasoline for the same net driving/flying range, could weigh about the same as the gasoline. So, a typical car with maybe a 16 gallon tank and 30 miles per gallon fills up with 128 pounds (58 kg) of gasoline to get 480 miles of range. The Li-Ion battery for that range would weigh something like 1300 Lbs (590 kg). That is a substantial additional weight for a car that could be 2800-3800 Lbs in ICE configuration, so 35-45% added weight (a bit less because of savings on the ICE engine, etc). This requires everything else to also be heavier, from the structural frame, the suspension system, and even the wheels and tires (which is also unsprung weight, further impairing performance).
With a 130Lb/60kg battery instead, and saving the weight of the ICE engine and fuel system, the overall car design could go much more lightweight, regaining a lot of performance and range, all while gaining the huge torque of electric motors.
In aviation, a battery systems of that weight would enable all-electric aviation to go from small performance niches to the default for general aviation.
So yes, it would be a HUGE benefit to achieve 10X energy density batteries, and we do have reference points for people to imagine it.
> With a 130Lb/60kg battery instead, and saving the weight of the ICE engine and fuel system, the overall car design could go much more lightweight, regaining a lot of performance and range, all while gaining the huge torque of electric motors.
I think you're underselling it, even. A typical like-for-like modern EV is only marginally heavier than the ICE equivalent. If we were able to drop the weight of the battery by a thousand pounds, cars would be lighter than they have been in decades while retaining all the modern safety and convenience features we've come to expect. And if density improved along with weight, we could make EVs with the same form factor as today but with over a thousand miles of range. Not that we need that, but it is just as a tiny example of how mind boggling the game change would be.
As it is I've only recently internalized the notion that the most powerful electric tools are battery powered (what can I say, I grew up when rechargeable batteries were NiCad and they basically sucked). And it will just get better and better as time goes on.
An EV doesn't need to have 480 miles of range. Nobody is driving that distance daily. 98% of trips are under 50 miles. Only 0.8% of the trips are over 100 miles!
Also, EVs use regenerative braking. That should help a little bit.
EVs should be built with 100 - 150 mile range. All families with 2 cars can immediately switch one of their cars to a daily driver EV and the other vehicle is a minivan. There are lots and lots of people for whom an EV works perfectly well and if they need to go longer, US has a robust rental car industry. What would help is to let people charge anywhere they park. All workplaces should offer free charging, and companies can negotiate to get paid for charging their employees cars. The price of electricity goes negative because of lack of demand, and this is something that they can offer to the grid, demand as a service.
I think people can imagine lighter cars and laptops and things. Is there something bizarre that’s unlocked like battery powered space launches or something?
High density batteries allows us to have dramatically cheaper electricity. Think of it like this, what happens when electricity is 1/10th the cost? Beyond what others have pointed out (electric airplanes, cars that drive thousands of miles), costs for everything would drop as energy is a core driver of it in every good you consume. If you can pull energy where it's very cheaply available and store/transport it anywhere the world millions of lives would be saved. For example;
If energy is cheaper than the price of water you can pull water out of thin air (dehumidifiers).
If energy is cheaper you can grow food in areas you normally couldn't.
When you can transport anything for cheap you can move food to areas that are vulnerable to food insecurity.
If you can store energy at large scale you can nearly eliminate grid failures, savings lives in the summer and winter.
Costs for transporting food would go down significantly, imagine groceries being 10-15% cheaper.
Assuming airlines have competitive pressure you could expect plane flight costs to drop 20-30% improving everyone's mobility.
Aviation, drones with hours+ flight range, more solar power usage as storage gets easier/cheaper, phones that last more than a day, robots with actually useful battery life, smaller IoT devices. A lot of current tech is severely limited by battery capacity.
A 1 GWh grid scale battery takes up about 4 hectares at the moment. The UKs total energy use is about 2,000GWh a day.
It would need to use 240,000 hectares to store all energy requirements (eletric, transport, heating etc) for a whole month. Even in extreme cold conditions it would last a couple of weeks.
Storing a month of energy use doesn't make any sense when it comes to renewable grids. Since you don't have to mine/extract and transport an inventory, far far less storage is required.
Instead of batteries, why not green hydrogen or green ammonia? Ammonia is needed for fertilizer, storage/logistics are a solved problem. Emergency plants around that can use ammonia as fuel can solve the dunkelflaute problem?
Another option is natural gas peaker plant on a ship/barge. Have a fleet of these around that can dock at any port and supply electrictity. A peaker powership is essentially a mobile, marine-class version of an onshore peaking power plant.
What would be best long term if we have a few hundred - few thousand nuclear ships/subs that can go anywhere and supply power.
It can be the sharing economy for clean power at scale.
Aren't sodium batteries close to production and a lot cheaper and safer?
Ambri was working on large scale batteries which seemed like a pretty good idea (looks like they ran out of money): https://en.wikipedia.org/wiki/Ambri_Inc.
Sodium ion batteries are already being mass produced in China. CATL actually just started producing their second generation sodium ion batteries. In the US, Peak energy is doing storage solutions based on sodium ion.
Anyway, you are comparing apples and oranges. While solid state sodium ion might become a thing at some point, it so far isn't. The lithium based solid state batteries currently being readied by several battery companies for mass production around 2028 or so tend to have up to 500-600 wh/kg densities. Sodium ion batteries are currently at or below 175 wh/kg typically. LFP is a bit better, and some high end NMC batteries might do 250ish wh/kg. That would be just the first generation solid state batteries. Densities might improve after that. The theoretical limit is a lot denser than that and there is a lot of money going into researching ways to do better than that.
Of course energy density is just one thing you might optimize for. Other properties you might look at are operating temperatures, amount of charge cycles the battery can handle before it degrades below 85% of its original capacity, the speed at which it can cycle, fire safety, cost, etc. Mostly sodium ion scores very well on all of this except density.
High energy density usually comes at a price. Both in dollars and in compromises with these other things. Think lower lifetime, more constrained temperature ranges, etc. Worth it if weight and volume are really constrained. Like in anything that flies.
Depends on the application - each battery technology has a trade-off between energy density, cost, lifetime, safety, scalability, etc. Sodium may have a place in grid storage, although iron-air is being deployed today and is even cheaper and safer (but poor energy density, which doesn't matter much for grid storage - https://formenergy.com/technology/battery-technology/)
The Two Bit Da Vinci YouTube channel has a good video on solid state battery fundamentals and a deep dive into a battery company (ProLogium) that has demonstrated manufacturing at scale.
The energy density scatter plot is physically correct but misleading and everyone makes this mistake.
From an engineering point of view you have to use work delivered at the end of the drive train not fuel raw energy content.
When you do that lithium ion batteries compare more favorably to liquid fuels. That’s because the conversion path is more than 90% efficient. For ICE engines you’re starting with only 20-40% Carnot efficiency (depending on how good and in good shape the engine is) and then losing in the transmission and then losing more because ICE cars have more other gears and moving parts. Power to wheel is pretty terrible. Most of the energy from gasoline heats the air around the car.
This is also why you get outrageous sounding but accurate things like: an EV charged on 100% coal fired electricity emits less carbon than a typical gasoline car. The fact that coal is literal pure carbon fuel is made up for by the high thermal efficiency of a giant supercritical steam turbine vs a small piston engine. Coal burns real hot too (steeper thermal gradient). So more of the energy from coal ends up doing actual work vs heating the air. (Well directly heating the air I mean.)
Yes, electricity should be the only abstraction layer to deliver energy to end user. We can extract a lot more energy from fossil fuels in large scale plants and also continuously switch out dirtier fuels with clean energy.
For example, no need to build natural gas infrastructure to every home. Use induction stoves (or electric coil -- already 67% of homes). Heat pump water heater instead of gas. And heat pump for HVAC.
If all energy bills are consolidated as electricity (instead of gas, natural gas and electricity), most people would install solar on their rooftops, buy EVs, and save ~$1000/month on energy bills.
> We can extract a lot more energy from fossil fuels in large scale plants
This isn't true at all for natural gas. Burning it for heat in the home is much more efficient than burning it in a plant, converting it to electricity, transferring that electricity, then turning that electricity into heat.
> because the liquid electrolyte currently used in batteries is flammable, replacing it with a solid could make batteries safer and less susceptible to fire.
The problem is primarily that batteries are storing a lot of energy, which can be released when things go wrong. The electrolytes (technically, the solvents) typically don't ignite under 750°F or so, which makes them less flammable than a lot of other common materials, and far less of a concern than, say, the lithium metal.
The liquid electrolyte is the thing that releases most energy when the battery burns, more than the anode and cathode. Some also have a very low self ignition temperature.
IIUC, the main problem with the current Li batteries is that the two plates can over time grow material that will 1) degrade performance; and 2) make it more likely to short circuit and catch fire. Similarly with electric car batteries after accidents where the battery is damaged, short circuits, and then catches fire.
So the main risk here would be the likelyhood of short circuiting under different failure scenarios.
The energy "stored" in the light oil electrolyte of a battery is >10x more than the electrical energy or the energy released by reacting lithium alone.
An 18650 battery weighs ~50g and stores ~10 watt-hours. 10 watt-hours is 8,604 calories, enough to heat 50g of water by 172 C or 310 F. The battery would not even burn without a liquid electrolyte to ignite.
you ever short a car battery? That much electricity running through metal will create a lot of heat which then ignites the lithium. Watch a video on thermite and you'll get the idea.
Manufacturing the batteries would probably benefit from solid state. The Panasonic battery plant in the exurbs of Kansas City, MO has had two evacuations this year from thermal issues related to lithium-ion battery production, including one yesterday morning. [0] [1]
have I misread or 3/4 of the article explained what a battery is and only final tiny part got to "short-circuiting dendrites don't happen without electrolite"?
There are a number of reasons why lithium batteries may catastrophically fail and catch fire. Dendrite shorts is one, another reason is poor alignment of the layers during assembly, allowing for eventual shifting of layers leading to internal shorting. Another is conductive or sharp debris getting into the battery during manufacturing, and after a while the anode/cathode separator getting pierced by the debris. Lots of reasons!
dendrites are not really a significant problem in popular batteries. It's associated with lithium metal, vs lithium in normal batteries is in the form of salts. Solid state lets you use metal, which is much more energy dense since you don't need the salts.
The most common lithium battery failure mode is that you have a hole in the plastic separator between the +/- sheets inside the battery, which shorts and causes a hotspot that eventually starts a fire. Dendrites cause the short by growing across the gap. In normal batteries it is caused by a manufacturing defect. The outcome is pretty similar.
Solid state batteries come in several flavours. Most of them don't stop dendrites.
The flavour you want is polymer, single ion conducting solid state with an ion transport activation energy below 10kJ/mol at room temperature and no phase transitions from -40C to 80C.
That is the holy grail of SS batteries.
> The flavour you want is polymer, single ion conducting solid state with an ion transport activation energy below 10kJ/mol at room temperature and no phase transitions from -40C to 80C.
what makes it so? I don't know anything about this subject, I'm really curious now about what the perfect battery would be.
No idea why polymer single ion conducting would stop dendrites (I know people are looking for it, I don't know why).
But 10kJ/mol of activation energy is another way of saying less than 100mV of internal loses, and avoiding phase transitions means that your battery won't stop working on that temperature range.
I’m still a novice on the material science behind it, but what is QuantumScape lacking here if anything, and why is it a dealbreaker?
The only thing different from this list is the ceramic separator. It’s not polymer. However, the ceramic is ultra thin to the point that it’s flexible so volume expansion isn’t a problem and it solves the dendrite problem.
Perhaps a polymer will be invented that can’t be pierced by dendrites. But existing polymers need to be heated for ion transfer efficiency and are combustable.
Technically, QuantumScape also uses an organic liquid catholyte inside the cathode. So it’s not “pure” solid state.
Are anyone building the battery you described?
No. The holy grail goes undiscovered for now.
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Aliens somewhere, presumably.
"no phase transitions from -40C to 80C."
Well that's fine for terrestrial use but aerospace needs that range to be expanded a little in both directions, otherwise it won't be much of a holy grail if it won't cover the needs of one of the largest growing industries.
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If you know a bit about electronics, you might be a bit surprised by the term 'solid-state battery'. It's a poor analogue to the more common usage of solid-state with semiconductors, integrated circuits, etc. -- a "solid-state" cell is still a chemical cell. It's not a paradigm shift on the level of, say, replacing a relay with a MOSFET.
The article gives the technical reasons that answer the headline question (e.g. potential for better energy density)
I am surprised they didn't point out the literal "killer app" - military drones. Energy density is king for any airborne power source. And dendrite growth during charge/discharge cycling isn't as big a deal for that application (how many times would you need to charge a disposable weapon?)
For disposable applications like that, aren't there single-use chemistries that are better already? I'm thinking by analogy to things like:
- WW2 proximity fuzes that had batteries where the electrolyte was in a vial that got smashed by the G-forces of being shot out of a cannon providing power to the radio inside for the 10 seconds it needs to get to the incoming aircraft
- Hearing aid Zinc-Air batteries, that are extremely energy dense because you only have to actually manufacture the anode, the cathode is the entire atmosphere of the Earth
- Missile batteries, which are often Lithium-silicon/Iron Disulfide batteries that borrow some thermal energy from the rocket motor to get a molten salt electrolyte
If the thing is going to blow up anyway, does it need to be light? Wouldn't you rather have more cheaper drones?
Less weight (all else being equal) is the same thing as more battery for drones. I.e. better range, payload mass, and/or flight time. You probably want both cheap and poor performing as well as expensive and high performing available.
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The lighter the further range or more explosive payload.
We need way more research on batteries. People cant ingine what is possible if we make battery 10x energy dense.
I can - it’s called a bomb. Some of the problems with batteries are heat dissipation (one of those problems that superconductors would mostly solve), fire safety, and end of life disposal. Higher energy density makes it even worse.
A good place to start would be a BMS on individual cells that monitors them for general degradation, unexpected discharge, unexpected temperature changes, and can remove a failing cell from the array.
Gasoline has 10x the energy (MJ/Kg) than TNT, but it's not a "bomb". Being a "bomb" is about energy release rate. A battery is still controlled by its chemistry.
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Some heavier elements have hilariously high energy densities and aren't bombs (on their own), but the catch is the energy release is a trickle. Point is it's not an automatic follow that high density = high discharge.
Have a look at Electric impedance spectroscopy- https://en.wikipedia.org/wiki/Dielectric_spectroscopy
Theres a handfull of Tier 1 BMS chips that support it already. though, half of them are meant for traction/EV packs instead of BESS.
Making it require air (or some other kinetic / transport process) would help with that. E.g. zinc-air battery.
The past 20 years have made lithium ion 2-3x more dense, both because of some chemistry changes and because of better pack level design.
And it's still improving at about 5% per year.
Tesla has been around for nearly 20 years. Model S (12 years) has gained 17% of range due to chemistry (rest is system efficiency and simply bigger battery).
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I don't think 10x density is possible without getting into nuclear, at least not with the chemistries we know of today, everything at a certain point becomes an explosive.
Speaking of nuclear, getting tons of the material that powers mars rovers and putting them in every home would generate enough power for decades... At the cost of being able to build a nuclear bomb in a garage.
The next revolution will be small scale generation. Fuel cells, extremely efficient cheap solar, even smaller modular reactors, etc.
I live in western Pennsylvania and have both natural gas and electric service, a roof and 1/3 acre of land to utilize. I would love to get rid of at least one of my utility bills and I’m becoming more interested in decoupling from the electric grid than natural gas service. I dream of a future where competition comes to monopoly utilities by way of direct competition with each other as there is a not so far off future where I can utilize solar, batteries and a natural gas fuel cell to cut ties with my Electric Utility. If that kind of competition can exist then the game is on for those utilities to start fighting for customers.
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I seem to remember recent advances in TMSR research and construction. Those tend to e much safer and have safer byproducts than uranium or plutonium fueled water-cooled reactors.
In term of dual use nuclear seems culturally radically different from everything else, wondering why.
Agreed, but I think people can imagine and companies are very motivated: powertools, phones, laptops, watches, backup UPS, cars, hospital equipment... there's high demand for durable, long-lasting batteries. I think the research is there, it's just complex chemistry. We'll get there. Impressive to see the progress in EV batteries and they've actually turned out to be more durable than first feared.
hard core lipo user here(for DIY). battery is great but it gets balloon after using some time
How is billions every year on R&D not enough, especially when you measure consistent improvement year over year in the technology?
10x energy dense does not mean 10x safer. Gasoline is still widely used because it is considered one of the safest options around!
The problem is more nuanced than just "let's do all the battery density"
maybe you are right . I was thinking a world where battery improvement is the rate as chip performance improvement ,
I think, apart from finding better Batteries altoghether, we should build multi-tier batteries inspired by biology. Humans have bloodsugar, sugar in the Liver and then fat. All of them have their respective properties with availability and amount. This way, engineering tradeoffs could be allocated much more fine grained. For example, a while ago I read about a startup building an energy storage where they heat up large amounts of sand to store the surplus of renewables. This could serve analogous to the fat in humans.
sorry in advance , but my POV is .
Most of the things that we copy directly from humans do not work in terms of robustness.
Its like instead of harddrive use human DNA to store the data for 3T years,but no-one is mentioning the bandwidth speed here(which is the most important thing) etc,
I know it has some usecases.Also "one spoon butter is more energy dense than a battery"
but how we are gonna use butter(I dont know enough bio) but it is way harder to convert energy .
Biological power is marvelous, but really inefficient. All that sugar and fat in entire human body only generates 50-150 Watts.
Humans do that because we're big and extra complicated. The closest analogue is probably a hybrid car, though ideally you'd want one that can create synthetic fuel from its battery. But I suspect cellphones are properly analogous to e.g. bacteria that have much simpler energy storage.
I think I've heard of sodium, lithium hybrids. But that's only 2, what's the fat? Gasoline, LPG hybrid? Shit gets expensive fast. Probably 2x cost of just a sodium or ion EV? The human body is too amazing.
I look to a future of regularly servicing the immune system of my battery.
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The good news is that humans already exist, so you can already use them. It will give them something to do with AI replacing them elsewhere.
You might not like the efficiency of that type of battery, though.
The article says $4B was put into solid state research/companies as of 2025 in the US alone. Seems like they are working on it
It should be relatively straightforward to imagine — we already have that in gasoline-powered internal combustion engines.
The Watt-hours per kilogram of good Lithium Ion batteries is around 250-280 Wh/Kg; for Lithium Iron Phosphate it's about 180 Wh/kg, and for Sodium-Ion about 170 Wh/Kg.
The raw energy in gasoline is about 12,300 Wh/Kg but automobile internal combustion engines get only about 20-30% efficiency yielding about 2500-3600 Wh/Kg. For aviation piston engines it is a bit better at 25-30$ so 3000-3600 Wh/kg.
So, the batteries, instead of being 10-12X the weight of the gasoline for the same net driving/flying range, could weigh about the same as the gasoline. So, a typical car with maybe a 16 gallon tank and 30 miles per gallon fills up with 128 pounds (58 kg) of gasoline to get 480 miles of range. The Li-Ion battery for that range would weigh something like 1300 Lbs (590 kg). That is a substantial additional weight for a car that could be 2800-3800 Lbs in ICE configuration, so 35-45% added weight (a bit less because of savings on the ICE engine, etc). This requires everything else to also be heavier, from the structural frame, the suspension system, and even the wheels and tires (which is also unsprung weight, further impairing performance).
With a 130Lb/60kg battery instead, and saving the weight of the ICE engine and fuel system, the overall car design could go much more lightweight, regaining a lot of performance and range, all while gaining the huge torque of electric motors.
In aviation, a battery systems of that weight would enable all-electric aviation to go from small performance niches to the default for general aviation.
So yes, it would be a HUGE benefit to achieve 10X energy density batteries, and we do have reference points for people to imagine it.
> With a 130Lb/60kg battery instead, and saving the weight of the ICE engine and fuel system, the overall car design could go much more lightweight, regaining a lot of performance and range, all while gaining the huge torque of electric motors.
I think you're underselling it, even. A typical like-for-like modern EV is only marginally heavier than the ICE equivalent. If we were able to drop the weight of the battery by a thousand pounds, cars would be lighter than they have been in decades while retaining all the modern safety and convenience features we've come to expect. And if density improved along with weight, we could make EVs with the same form factor as today but with over a thousand miles of range. Not that we need that, but it is just as a tiny example of how mind boggling the game change would be.
As it is I've only recently internalized the notion that the most powerful electric tools are battery powered (what can I say, I grew up when rechargeable batteries were NiCad and they basically sucked). And it will just get better and better as time goes on.
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An EV doesn't need to have 480 miles of range. Nobody is driving that distance daily. 98% of trips are under 50 miles. Only 0.8% of the trips are over 100 miles!
Also, EVs use regenerative braking. That should help a little bit.
EVs should be built with 100 - 150 mile range. All families with 2 cars can immediately switch one of their cars to a daily driver EV and the other vehicle is a minivan. There are lots and lots of people for whom an EV works perfectly well and if they need to go longer, US has a robust rental car industry. What would help is to let people charge anywhere they park. All workplaces should offer free charging, and companies can negotiate to get paid for charging their employees cars. The price of electricity goes negative because of lack of demand, and this is something that they can offer to the grid, demand as a service.
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I think people can imagine lighter cars and laptops and things. Is there something bizarre that’s unlocked like battery powered space launches or something?
High density batteries allows us to have dramatically cheaper electricity. Think of it like this, what happens when electricity is 1/10th the cost? Beyond what others have pointed out (electric airplanes, cars that drive thousands of miles), costs for everything would drop as energy is a core driver of it in every good you consume. If you can pull energy where it's very cheaply available and store/transport it anywhere the world millions of lives would be saved. For example;
If energy is cheaper than the price of water you can pull water out of thin air (dehumidifiers).
If energy is cheaper you can grow food in areas you normally couldn't.
When you can transport anything for cheap you can move food to areas that are vulnerable to food insecurity.
If you can store energy at large scale you can nearly eliminate grid failures, savings lives in the summer and winter.
Costs for transporting food would go down significantly, imagine groceries being 10-15% cheaper.
Assuming airlines have competitive pressure you could expect plane flight costs to drop 20-30% improving everyone's mobility.
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Aviation, drones with hours+ flight range, more solar power usage as storage gets easier/cheaper, phones that last more than a day, robots with actually useful battery life, smaller IoT devices. A lot of current tech is severely limited by battery capacity.
Electric long distance passenger planes. Possibly requiring the help of EMALs.
Electric long distance container ships.
Useful portable laser, coil- and rail- guns.
Even longer range drones.
What point is there in gasoline if we can get better energy storage in batteries?
Not all batteries need to be mobile.
A 1 GWh grid scale battery takes up about 4 hectares at the moment. The UKs total energy use is about 2,000GWh a day.
It would need to use 240,000 hectares to store all energy requirements (eletric, transport, heating etc) for a whole month. Even in extreme cold conditions it would last a couple of weeks.
That would be about 1% of land use.
Storing a month of energy use doesn't make any sense when it comes to renewable grids. Since you don't have to mine/extract and transport an inventory, far far less storage is required.
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Instead of batteries, why not green hydrogen or green ammonia? Ammonia is needed for fertilizer, storage/logistics are a solved problem. Emergency plants around that can use ammonia as fuel can solve the dunkelflaute problem?
Another option is natural gas peaker plant on a ship/barge. Have a fleet of these around that can dock at any port and supply electrictity. A peaker powership is essentially a mobile, marine-class version of an onshore peaking power plant.
What would be best long term if we have a few hundred - few thousand nuclear ships/subs that can go anywhere and supply power.
It can be the sharing economy for clean power at scale.
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fun fact: there is already a Sodium-battery with a solid electrolyte - but the operating temperature is above 300^C [0] [0] https://en.wikipedia.org/wiki/Sodium%E2%80%93sulfur_battery
When titles with rhetorical questions sound almost like dumb questions.
Aren't sodium batteries close to production and a lot cheaper and safer?
Ambri was working on large scale batteries which seemed like a pretty good idea (looks like they ran out of money): https://en.wikipedia.org/wiki/Ambri_Inc.
Sodium ion batteries are already being mass produced in China. CATL actually just started producing their second generation sodium ion batteries. In the US, Peak energy is doing storage solutions based on sodium ion.
Anyway, you are comparing apples and oranges. While solid state sodium ion might become a thing at some point, it so far isn't. The lithium based solid state batteries currently being readied by several battery companies for mass production around 2028 or so tend to have up to 500-600 wh/kg densities. Sodium ion batteries are currently at or below 175 wh/kg typically. LFP is a bit better, and some high end NMC batteries might do 250ish wh/kg. That would be just the first generation solid state batteries. Densities might improve after that. The theoretical limit is a lot denser than that and there is a lot of money going into researching ways to do better than that.
Of course energy density is just one thing you might optimize for. Other properties you might look at are operating temperatures, amount of charge cycles the battery can handle before it degrades below 85% of its original capacity, the speed at which it can cycle, fire safety, cost, etc. Mostly sodium ion scores very well on all of this except density.
High energy density usually comes at a price. Both in dollars and in compromises with these other things. Think lower lifetime, more constrained temperature ranges, etc. Worth it if weight and volume are really constrained. Like in anything that flies.
Depends on the application - each battery technology has a trade-off between energy density, cost, lifetime, safety, scalability, etc. Sodium may have a place in grid storage, although iron-air is being deployed today and is even cheaper and safer (but poor energy density, which doesn't matter much for grid storage - https://formenergy.com/technology/battery-technology/)
Cheaper yes. Non-aqueous sodium ion batteries (which are most of them) are more dangerous than LiFePO4 though.
In what way, if you don't mind me asking?
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The Two Bit Da Vinci YouTube channel has a good video on solid state battery fundamentals and a deep dive into a battery company (ProLogium) that has demonstrated manufacturing at scale.
https://youtu.be/xQFVIs4leig?si=iOOt5gg_2MJAIoFR
BYDs battery stress testing: https://www.youtube.com/watch?v=WPTgg3joL5E
Those use liquid electrolyte cells and the video is more promo than rigorous testing.
Tangential to the main article point but…
The energy density scatter plot is physically correct but misleading and everyone makes this mistake.
From an engineering point of view you have to use work delivered at the end of the drive train not fuel raw energy content.
When you do that lithium ion batteries compare more favorably to liquid fuels. That’s because the conversion path is more than 90% efficient. For ICE engines you’re starting with only 20-40% Carnot efficiency (depending on how good and in good shape the engine is) and then losing in the transmission and then losing more because ICE cars have more other gears and moving parts. Power to wheel is pretty terrible. Most of the energy from gasoline heats the air around the car.
This is also why you get outrageous sounding but accurate things like: an EV charged on 100% coal fired electricity emits less carbon than a typical gasoline car. The fact that coal is literal pure carbon fuel is made up for by the high thermal efficiency of a giant supercritical steam turbine vs a small piston engine. Coal burns real hot too (steeper thermal gradient). So more of the energy from coal ends up doing actual work vs heating the air. (Well directly heating the air I mean.)
Yes, electricity should be the only abstraction layer to deliver energy to end user. We can extract a lot more energy from fossil fuels in large scale plants and also continuously switch out dirtier fuels with clean energy.
For example, no need to build natural gas infrastructure to every home. Use induction stoves (or electric coil -- already 67% of homes). Heat pump water heater instead of gas. And heat pump for HVAC.
If all energy bills are consolidated as electricity (instead of gas, natural gas and electricity), most people would install solar on their rooftops, buy EVs, and save ~$1000/month on energy bills.
> We can extract a lot more energy from fossil fuels in large scale plants
This isn't true at all for natural gas. Burning it for heat in the home is much more efficient than burning it in a plant, converting it to electricity, transferring that electricity, then turning that electricity into heat.
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> because the liquid electrolyte currently used in batteries is flammable, replacing it with a solid could make batteries safer and less susceptible to fire.
The problem is primarily that batteries are storing a lot of energy, which can be released when things go wrong. The electrolytes (technically, the solvents) typically don't ignite under 750°F or so, which makes them less flammable than a lot of other common materials, and far less of a concern than, say, the lithium metal.
This isn't true for most lithium ion chemistries.
The liquid electrolyte is the thing that releases most energy when the battery burns, more than the anode and cathode. Some also have a very low self ignition temperature.
IIUC, the main problem with the current Li batteries is that the two plates can over time grow material that will 1) degrade performance; and 2) make it more likely to short circuit and catch fire. Similarly with electric car batteries after accidents where the battery is damaged, short circuits, and then catches fire.
So the main risk here would be the likelyhood of short circuiting under different failure scenarios.
The energy "stored" in the light oil electrolyte of a battery is >10x more than the electrical energy or the energy released by reacting lithium alone.
An 18650 battery weighs ~50g and stores ~10 watt-hours. 10 watt-hours is 8,604 calories, enough to heat 50g of water by 172 C or 310 F. The battery would not even burn without a liquid electrolyte to ignite.
Isn't the key difference that flammable solids have a limited reaction surface when they burn, whereas flammable liquids can be wildly unpredictable?
I wonder about the youtube videos of someone driving a screwdriver through a battery pack.
Is that the electrical discharge, then the lithium going off, then the electrolytes?
you ever short a car battery? That much electricity running through metal will create a lot of heat which then ignites the lithium. Watch a video on thermite and you'll get the idea.
I'm not trying to build a solid-state battery...
Manufacturing the batteries would probably benefit from solid state. The Panasonic battery plant in the exurbs of Kansas City, MO has had two evacuations this year from thermal issues related to lithium-ion battery production, including one yesterday morning. [0] [1]
[0]https://www.kmbc.com/article/lithium-ion-batteries-catch-fir...
[1]https://www.kmbc.com/article/panasonic-plant-de-soto-evacuat...
Yeah I've made peace with this too
have I misread or 3/4 of the article explained what a battery is and only final tiny part got to "short-circuiting dendrites don't happen without electrolite"?
dendrites are an inherent problem with liquid elctrolytes and I would have emphasized that as well
are dendrites why so many people are now burning down their apartment/complex charging their scooters
is LiFePo4 immune to dendrite shorts? Or do they happen just don't burn?
There are a number of reasons why lithium batteries may catastrophically fail and catch fire. Dendrite shorts is one, another reason is poor alignment of the layers during assembly, allowing for eventual shifting of layers leading to internal shorting. Another is conductive or sharp debris getting into the battery during manufacturing, and after a while the anode/cathode separator getting pierced by the debris. Lots of reasons!
dendrites are not really a significant problem in popular batteries. It's associated with lithium metal, vs lithium in normal batteries is in the form of salts. Solid state lets you use metal, which is much more energy dense since you don't need the salts.
The most common lithium battery failure mode is that you have a hole in the plastic separator between the +/- sheets inside the battery, which shorts and causes a hotspot that eventually starts a fire. Dendrites cause the short by growing across the gap. In normal batteries it is caused by a manufacturing defect. The outcome is pretty similar.