Chinese company claims it's built batteries so dense they can power electric airplanes The world’s top EV battery maker, China's Contemporary Amperex Technology Co. Limited (CATL), announced on Wednesday a battery it believes boasts sufficient energy density to power electric airplanes. The 500 Wh/kg battery was launched at Shanghai International Automobile Industry Exhibition, also known as Auto Shanghai, with …
500 wh/kg will open up a number of applications in aviation.
Do not expect battery powered airliners with these numbers, but battery powered General Aviation (CS 23) becomes competitive in quite a few applications.
On the other hand, pouch cells are not suited for rapid changes in atmospheric pressure, so hopefully they will develop standard format cylindrical cells.
"a larger amount of exhaust gasses"
Just due to the expansion of the air when heated. It's called the Brayton cycle. The source of the heat is of secondary importance, as is the mass flow component of the fuel as a contribution to the thrust.
Nuclear powered Jet Engines?
https://en.wikipedia.org/wiki/Nuclear-powered_aircraft
https://whatisnuclear.com/safety-minutes/htre-3-meltdown.html
Many many issues, but I would hope for better planning & engineering practices than this example from Thunderbirds - Trapped In The Sky!
Captain Hanson: "Well, with our atomic motors, we can stay up here for six months. But the anti-radiation shield on the reactor will need servicing in two hours, ten minutes, or our passengers will be subjected to radiation exposure."
You can just heat the air directly. The US built a direct cycle ramjet and ran a few successful ground tests (PLUTO) and also built a direct cycle turbojet (though this was never tested as propulsion). The Soviets had a similar programme, taken critical in flight but never used for sole propulsion in the same way as the US.
Indirect cycle is also theoretically possible, though less efficient.
Forget about the weight of the reactor.. there is the hardened concrete housing, the grass covered perimeter areas, the double fencing, the guards, the gatehouses, etc. etc.
Getting all of that onto your nuclear airliner (as invented by feynmann) will be difficult.
I did love the US air force approach to the nuclear bomber, just use older crew!
Every time I see press releases like this I expect to see some reference to prefabulated aluminite. It is hard to tell if they are being serious or taking the piss with some of the technical terms.
And aircraft carriers, of course.
Nuclear powered cargo and passenger ships were almost a thing.
There was a cruise missile design based on that principle. It used nuclear fuel rods to power its flight and would cause nuclear fallout as it moved around. It was as horrible as you could ever imagine.
But the plane itself never ejected chunks of the core. In fact, it never powered itself with the reactor, they never connected the whole thing to the conventional jets on the plane, just tested powering it up.
Search Project Pluto, wikipedia. and the plane as NB-36H, nuclear powered aircraft.
It used nuclear fuel rods to power its flight and would cause nuclear fallout as it moved around
I'm surprised Putin doesn't want to build that, and just have them circling around major Ukrainian cities. It would fit in well with his concept of war as being against civilians as much as the opposing military. Even if they are successfully shot down they cause even more fallout, while still allowing him to claim that Russia has not used nuclear weapons.
So after just 25 cycles the battery has already beaten the liquid fuel.
You could have just gone for matter itself which has an energy density of 1.5e13Wh/kg.
Your precious petrol has a couple of serious disadvantages
- you can only access 30% of that energy usefully
- you need a fairly heavy conversion engine
So it's not actually 12kWh/kg if you want to use it in a vehicle... and it gets worse and worse with a small fuel tank.
yes, but you land, spend a few minutes pumping kerosene in to the tanks, then take off again. The point about liquid fuel is that it is consumed, and is then easily replaced. A battery is still heavy when it contains no energy, then must be recharged. Which takes longer.
If you recharge faster, you bring forward the time when the battery must be discarded and replaced. Replacement normally is not economically viable.
My ICE engine can just have a few hundred quid's worth of spannering, and it 's good to go.
Even at 30% efficiency, that's still 3.6kWh as against 0.5kWh.
And expanding on the "battery is still heavy" point, this is of particular importance in the aviation world due to the need to design the aircraft to land safely weighing as much as it did when it took off, which isn't something that's true for most aircraft at present.
Plus, given the need to lug 7.2kg of batteries around to give the same effective available energy as 1kg of kerosene, the weight savings you get from switching from ICE to electric motors doesn't get you very far - looking at general aviation stuff here, electric motors seem to go for around 30-40kg vs around 120kg for an equivalent power output ICE lump, so if you use that 80-90kg for batteries instead then that gives you as much energy as 12.5kg of kerosene, which is less than a tenth of the fuel capacity of a single engine GA aircraft.
Your electric aircraft could therefore at least take off and fly for a short period whilst weighing the same as an unfuelled ICE aircraft, but if you want it to be able to handle the same sort of tasks as an ICE-powered aircraft then you'd need to add more batteries, at which point the overall weight of motor+energy source very quickly starts to favour the ICE option. Hence why much of the talk about electric aircraft at present seems to be focussed on roles where short flight times aren't an issue - e.g. pilot training, where you might only need to be airborne for up to an hour - whilst the point continues to be raised (as in this article!) that electric propulsion still has a way to go before it can displace liquid fuels for the sorts of aviation roles where it'd have the biggest benefit (i.e. longer-distance/higher fuel-burn flights).
So whilst improvements in battery, motor etc. tech are all welcomed, let's not kid ourselves that electric propulsion is currently anywhere close to being a viable alternative to liquid fuels for aviation except in some niche cases.
>yes, but you land, spend a few minutes pumping kerosene in to the tanks, then take off again
Then spend hours servicing the engines
Battery power isn't going to replace plant-goop for 737s but it could enable a lot of quadcopter airport-city centre taxi services with short ranges and strict noise / pollution limits
Yes - it's still very energy dense.
But if your engine weighs as much as your fuel (easily possible in many applications)
Sticking with aviation... 737 Max engines (random newish plane) are about 4 tonnes each, and they carry up to ~20 tonnes of fuel. So that's actually probably 1/3rd engine and 2/3rds fuel (don't usually fully fuel an aircraft)
They also tend to be able land with just a shade under max takeoff weight - Modern Airliners suggests the difference is only 4 tonnes, and they burn (Quora, sorry no good source) about 8 tonnes of fuel during takeoff (don't know how far they include as takeoff). So the weight difference is pretty small - I imagine that the max landing weight is merely an engineering challenge.
There is no reason that the batteries should take any "aircraft time" to recharge - you simply load on replacements as you do cargo and charge at leisure.
And of course that's ignoring the other downsides of liquid fuels.
Swappable batteries can add a huge amount of weight, complexity and safety issues to a plane. Suddenly you've got to have some sort of structural element in the battery pack, and another in the plane, connectors that can reliable attach and detach, and some guarantee that they don't do the latter at the wrong time, and a whole load of additional mechanical and electronic systems to deal with robust swapping in unpredictable environments.
There's no "simply" about it - as demonstrated by the almost complete absence of swappable lithium batteries in cars.
Swappable battery packs aren't necessarily a problem designed in from scratch. We manage it with industrial vehicles.
But for short <30 min flights with a similar turn around time - like shuttles - a DC fast charger would work.
A lot of an electrical aircraft is simpler than a car. There us no regen charging. The load is a lot more constant, especially if it had supercaps for take off.
The lack of swappable batteries in cars is purely economics/infrastructure
"There's no "simply" about it - as demonstrated by the almost complete absence of swappable lithium batteries in cars."
But there are swappable batteries in all sorts of other applications, you just chose cars because they are the same as planes?
Swappable HGV batteries are definitely a thing.
"Modern Airliners suggests the difference is only 4 tonnes, and they burn (Quora, sorry no good source) about 8 tonnes of fuel during takeoff (don't know how far they include as takeoff)."
I believe "take off" in this context includes climbing to cruising altitude. Figures from Boeing suggest about 2300kg for a 737 and around 10000kg for a 747-400 freighter.
It could - but I imagine that they need to be able to perform an emergency landing with basically everything they took off with.
The difference is so thin that I suspect it's closer to an engineering decision (given this max takeoff weight this is the most we can ever be expected to land with, so we'll engineer to that) than a fundamental limit on landing performance.
Well I'm tetatively excited, but only somewhat so at the possible prospect of my 3.9kg ebike battery someday being replaced by a 1.38kg battery of the same capacity. Hopefully whatever cells those battery packs contain, will make their way into the hands of hobbyist ebike battery makers, as other cell types intended for electric cars have. 500 Wh/kg is quite the leap, I very much hope it's true. I also hope they don't burst into flames as easily, or burn as hot for as many hours unextinguishable without complete immersion in swimming pools.
I believe that the issue with Lithium batteries and their wonderful pyrotechnic abilities is that they're...still Lithium.
Following on from that, Sodium batteries would still be Sodium.
Complete immersion in a swimming pool would make the problem worse over a short period of time.
(I'm not a chemist and don't have the full picture on how Li-Ion batteries work and the exact form of the Lithium. I'd very much like to be wrong on this.)
Lithium Ion batteries don't have much metallic Lithium in them (IIRC, they should have no elemental Lithium, but as they degrade they can develop Li deposits internally). The bulk of the fire danger comes from the stored energy (makes sense from a thermodynamics standpoint). The rest of the danger comes from conventional combustion of the electrolyte and other components.
To reduce both the available energy and the odds of an adverse event happening in transport, we ship our (very large) batteries at <35% state of charge.
Water is the recommended extinguishing agent for large Li-Ion battery fires. It's readily available in large quantities, safe to handle, has large specific heat capacity, etc. It's also capable of neutralizing any hydrogen fluoride gas produced from the fire (a common byproduct for at least some chemistries)
HF combines with water to make hydrofluoric acid, so it seems counter productive to add water! The problem is, if you have HF floating around it turns to hydrofluoric acid in your eyes, on your skin, in your lungs, etc. If you drown the HF in lots of water, it's converted and quickly diluted to a safe level.
Not a chemist, but I work on >100kWh batteries (built with CATL cells) at $dayjob.
I don't think anyone doubts its achievable (prototypes have achieved it as the article mentioned) - but as sceptics have pointed (such as Yazami in that article) out the challenge is to have a battery that can be mass produced and keep up that level of performance after some real world use - no point in a battery that dips from 500 down to 300 in the space of a couple of years and it takes time to do all the proper tests. Though given they are an established battery maker likely to get something to market in a reasonable timescale and so we will likely soon find out if they degrade badly (or not) in typical use.
There's lots of good research going into all sorts of battery tech (with some potentially major power / weight improvements) but sadly most of them are a long way from producing a commercially available mass produced battery (a bit like the way that fusion has been achieved for a few seconds and by different teams but going from there to working fusion reactors has (so far) proved a step too far )
Depends on how often the plane will fly. This is obviously not fit for commercial aviation, but for a small privately owned aircraft that isn't flown daily or even weekly, and usually nowhere near the max range it is capable of?
Just like with vehicles, you have to start somewhere. If no one built electric cars until they could handle all vehicles up through long haul trucking and Greyhound buses we'd still be waiting.
Obviously the power/weight ratio needs to get far far better before it becomes something you might buy a ticket to fly along with 300 other people from LA to NYC, but that doesn't mean it is unworkable for all aviation segments.
The article is a bit scant on details (I guess that's the company keeping them secret from their press release)
"highly conductive biomimetic condensed electrolytes that create a miniscule micron-level net structure. The semi-solid-state battery also incorporates new anode and separator materials and cathode materials with ultra-high energy density."
...mostly marketing-speak, doesn't actually say much. Lithium-ion batteries have a theoretical upper limit of about 2MJ/kg, which is about 550 Wh/kg*, and while I'm far from being an expert, my 'spidey-senses' tell me that it's unlikely to get so close to the theoretical limit in practice. So more likely it's not Lithium at all (Could be Sodium, as the article mentioned one of the company's earlier batteries being Sodium-ion). There are various battery chemistries** that theoretically could go to well over 1000Wh/kg, and are expected to approach this figure in prectice.
For comparison, the petrol energy density of around 12,000 Wh/kg is what's stored in the fuel, but the best car engines are maybe 35%-40% efficient (I believe jet engine efficiency is also in this range). So in terms of effectively delivered power contributing to motion, it's more like 4200 - 4800 Wh/kg. And this is after many decades of research and development, it's unlikely to get much better. On the other hand, electric motors are over 98% efficient, so the energy in the battery is practically all available at the wheels / propellers. Still far from what liquid fuel can deliver, but close enough to electrify some short-haul aviation. (It's unlikely that prop-driven electric aircraft could get to more than half a jet engine speed, but quiet, slower, low-emission planes could land on small runways much closer to city centres, and match door-to-door travel times for short-haul flights vs jets that have to land further away from the centre)
* https://thebulletin.org/2009/01/the-limits-of-energy-storage-technology/#:~:text=But%20as%20currently%20designed%2C%20they%20have%20a%20theoretical,lithium-ion%20batteries%20might%20break%203%20mega-joules%20per%20kilogram.
**https://ars.els-cdn.com/content/image/1-s2.0-S240582971931102X-fx1_lrg.jpg
Consider my car making a 2000km trip. It has 117L=88kg of fuel, but needs a 150kg motor and ~25% efficiency.
The net result turns 12000Wh/kg to 1300Wh /kg.
(Not sure what the equivalent electric motor is, but ~50kg at a guess)
Petrol is spectacular when you burn it in a Coleman stove for heat, but not nearly so good in a car, though I think rather better for long haul aircraft where the fuel mass will be higher and the engine mass lower.
Still better than batteries, but less an an order of magnitude even today for cars.
"Sure, but not many people can afford an engine that costs 8 figures to buy, a 30-person team to maintain and lasts less than 5,000 km!!!!"
I've never noticed all of the emission gubbins being put on an F1 engine either. VW had to fiddle settings so their TDI engines would pass US testing yet still get 50+mpg. I recall that causing some issues for the company.
"For comparison, the petrol energy density of around 12,000 Wh/kg is what's stored in the fuel, but the best car engines are maybe 35%-40% efficient "
The source of the petrol has to be considered as well. It doesn't come out of the ground ready to stack in a car's fuel tank. It takes a load of electricity to refine the crude oil into petrol and then get it to a station where a bit more electricity is added to take it from the storage tanks to the car. None of that energy gets embodied in the fuel so it's not there to be extracted.
Not to mention the effort required to find it, drill the well, pump it out of the ground (and other stuff into the ground if it is produced in the US these days) which accounts for the barrels of oil needed to bring one barrel of oil to market continually increasing since the 1950s when all the easiest to exploit oil had already been found.
Obviously there is cost associated with mining lithium or sodium, that materials that go into building wind turbines and solar panels, etc. etc. so people can twist the numbers in either direction to fit their desired claim, but no one can deny that the EROI (energy return on investment) in oil will continue to decline. The same is not true for the renewable energy sector, which is still in the phase where it is still getting more efficient over time on an EROI basis and that looks to continue for quite a while yet.
We're probably already past crossover for passenger cars, but obviously we can't flip a switch and go all electric in a single day so that transition will take a couple decades yet. We'll reach an economic crossover for even jumbo jets someday, and even if the electric versions don't work as well (have to fly slower, have less range, etc.) once they become meaningfully cheaper to fly many airlines will buy them because they'll be able to price flights lower and we already know there's a huge market for cheaper flights or even entire airlines that make "discount" their brand. I might not want to fly to Australia at 400 mph instead of 650 mph, but adding an hour or two on a flight that currently takes two or four hours might be worth it if it saves enough money.
"but no one can deny that the EROI (energy return on investment) in oil will continue to decline. "
It depends on the oil. Light/Sweet has the best eROI and the tar sands in Canada are some of the worst. In a way you are correct in that when L/S crude is found, they pump the heck out of that reservoir until it's dry while not putting in as much recovery effort in wells that produce Heavy/Sour where it takes a lot of refining to shorten the Hydro-Carbon chains and remove the contaminants.
But that's the thing, new light/sweet discoveries are rarer and rarer, and more of the world oil consumption comes from more difficult sources like deep sea, fracking and tar sands every year. Thus the average EROI per bbl goes up every year, and will never stop going up.
I just knew this comment would turn out be useful. The figures you seek lie within.
Well to wheel efficiency is an important topic, however a bit tangential to this topic.
The focus for the potential of battery-powered aircraft is the energy per mass (and to a lesser extent, per volume). Therefore besides the mass of fuel, one has to consider the mass of the engines, and the efficiency in converting stored energy into movement. Inefficiencies that happen before the point of loading fuel / charging batteries are, so to speak, left on the ground at takeoff.
Similair applies, though to a lesser extent, for liquid fuel vs electric cars.
Whether that was tongue in cheek, I don't know, but in the case of liquid fuel, it can disperse quickly. and much of it was consumed in the initial kaboom outside of the buildings, as can be seen from the ball of flame erupting from the buildings after the planes hit.
These batteries are much less likely to disperse quickly, and will firstly act as a single kinetic projectile, rather than flowing past the obstructions, doing much more physical damage, and then probably starting a fire that will be impossible to put out in a building at altitude.
The testing of the steel beams after the fact for the 911 official report, to demonstrate that j-fuel fires can soften steel beams was done in very different conditions than were in the building. The fuel was contained in a pit directly below the steel beam being tested, which was exposed to the hottest part of the flames, rather than being encased in concrete as the floor rafts were in the buildings. It was the collapse of the floor rafts that was blamed for the catastrophic failure that caused the buildings to collapse, not the steel skeleton of the buildings. I'm actually still a little sceptical about the findings of the report. If the structures survived the first impact, I think that they should have remained standing, like almost every other high-rise fire in history.
Much of the fires in the buildings were paper and other combustibles in the buildings, with possibly some of the aluminium from the fabric of the aircraft contributing to the fire. I don't know for certain, but I would be very surprised if almost all of the j-fuel was not consumed in the first couple of minutes.
Moving somewhat away from the main topic here but whatever:
Steel undergoes a phase change in its crystal structure around the 750 degree C mark (give or take).
Jet fuel burns in an open environment at around 1000 degree C mark.
The initial impact is believed to have caused much of the fire resistant cladding to the structural elements to have been broken off.
Fire -resistant cladding specifically does NOT make a structure immune to a fire, it delays the effects, buying time for safe evacuation / for the fire to be extinguished. Even if the cladding had remained in place, it would not have necessarily stopped the beams hitting the phase-change temperature, softening and deforming.
The floor plate provided the lateral connectivity between perimeter and building core; when beams softened and floor sections collapsed, that bracing was lost.
The towers were not designed against progressive collapse - the lessons of the Ronan Point 1968 gas explosion had by that time been learnt by the UK construction industry, but didn't carry over to the US quick enough.
"Much of the fires in the buildings were paper and other combustibles in the buildings, with possibly some of the aluminium from the fabric of the aircraft contributing to the fire"
All of that along with a nice air flow by the building sticking up so high. A hybrid rocket engine is a lump of plastic or rubber with NoX as the oxidizer. Just consider how much plastic there is in an average office. Douse an office with kerosene and spark it off with a fan blowing and not much will be left.
The other thing keep these off commercial jetliners of course is that when you burn fuel, the fuel is gone. A battery is just dead weight. Consider that airliners which have to make emergency landings just after take off generally need to dump fuel to do so safely. What are you going to do with a battery, chuck it out the window into the sea? Actually, probably yes that...
Also on that subject, I suppose I would expect to see batteries in airlines as modular things that get swapped between each flight (no down time for charging). You would also be able to specify "I only need half-capacity for this trip", just as pilots do with fuel.
There is a lot in the economics of flying that would need to change for battery powered air liners.
"I suppose I would expect to see batteries in airlines as modular things that get swapped between each flight (no down time for charging)."
Very doubtful that would be allowed. The process required on aircraft for work being done on that scale isn't something that done in a hurry by PFY ramp staff. Varying a fuel load can be done as it's a liquid and still going into tanks with a well characterized weight characteristic. It would be tricky to vary the number of battery modules and there would also be the problem of depleting modules in one location and accumulating a bunch of them some place else. The same sort of problem shown with the same sort of thing being done with passenger cars.
The reason fuel is jettisoned is the landing gear, not risk of going up. The impact on landing is a lot harder than any bouncing on takeoff, and fuel is needed to make the next airport, so just about all planes take off at a much higher weight than the lamding gear is rated for. Then there is the wings, fuel is carried in the wings and a jarring landing with fully loaded wings will likely damage the airframe if there is a hard jolt. Airliners carry thousands of pounds of fuel in the wings, and are built as light as possible, so something has (and would) give if the plane landed with full tanks. If one or both wings bucked on landing, there would be a large leak, lots of sparks, a fire and possibly an explosion.
With batteries, the battery will weigh the same on takeoff as landing, so the plane will need to be built to land at the same weight as takeoff. They will also need to be constructed so that a belly landing can't get into the batteries. Ideally that would mean wing mounted batteries, but that will be a lot of weight on the wings for repeated landings.
Interesting points, never considered some of them. Having the batteries concentrered in the body would lead to larger in-flight stress, and concentrated in the wings, lead to a lot of landing stress - so they would have to be distributed all over. I wonder if it would also be possible to build battery packs as structural elements? It seems to work for cars, but might not be ideal for planes with higher maintenance and longer lifespan requirements.
"I wonder if it would also be possible to build battery packs as structural elements?"
Tesla is talking about this too but TANSTAAFL. If you needed to replace or service a battery pack that was part of the structure, you'd need to put the aircraft on a stand that supports it while you do the work and then verify that the work hasn't compromised the structure when you are done. With a car, a battery pack that is structural also means you'd need to put the car on a frame that holds the car's shape. There shouldn't be lots of times you might need to R/R a battery pack, but when you do the complication factor goes way up and it can only be done at a facility equipped to do that work.
On the other side of a fence from my manufacturing when I ran it there was a company that built aircraft servicing equipment. Cradles for engines and custom rolling scaffold sort of stuff. I got to know them and got to see the operation a few times and get a bit of background. Everything had to be sized to fit on a flatbed trailer as a whole or in pieces so it could be moved but it was much easier if they could get the aircraft to the place where this equipment was due to downtime being so costly. The scaffold was also a big investment so not every airport or service depot had an engine cradle for every model of engine the airline flew. 3rd party depots tended to have a large assortment. Translate that to electric aircraft and even EV's and the problem is easy to spot. You don't want to take your car in for service and find that the part that needs replacing requires removing the battery and the nearest shop with a stabilizing frame is hundreds of miles away and has a couple of weeks of work already booked for it.
"so just about all planes take off at a much higher weight than the lamding gear is rated for."
Not higher than the rating for a static load and margin for a less than ruler-flat runway. Absolutely right that the dynamic loads on landing would be too much for the landing gear. This would mean that for equivalent take-off weight, the landing gear would need to be much more robust (heavier). Mass is the enemy of anything that flies.
That would be "yes" and "probably no-one's". There is a lot of battery research being done in the open and I'm sure the Chinese have as much expertise as anyone else in turning a lab result into a production line.
Probably more, in fact, since they appear to be the world's production line. :(
Sounds a bit Fu Manchu…
I actually read some of Roemer's Fu Manchu novels during the covid interregnum - a bit Sexton Blake-ish and Boys Own but if you are not too concerned with modern sensitivities and clearly understand that they written in a very different world, they aren't too bad even when compared with the Buchan's Richard Hannay stories.
I think the first Fu Manchu story was written well before 1914 when China wasn't really a player on the world stage and the Manchu dynasty pretty much finished and also before the european powers hadn't started the suicidal insanity of 1914-18.
"... Liquid fuels such as petrol boast density of around 12,000 Wh/kg. ..."
You could have mentioned that a petrol engine weighs getting on for five times as much as an electric motor of the same power output.
Lycoming AEIO-580 piston engine : 235kW, 202kg = 1.16 kW/kg
Siemens SP260D electric motor: 260kW, 50 kg = 5.2 kW/kg
So the bigger the engine, the more weight you've saved if it's electric. :)
A typical air liner carries five tonnes of engines - although turbines are a lot more efficient than piston engines.
Let's take your examples here and assume that you keep the overall airframe mass the same, so that the difference in motor weight is used to provide battery capacity.
With these not yet available batteries, and assuming 30% efficiency for the petrol lump, you'd need 7.2kg of batteries to give the same effective energy capacity as 1kg of petrol, and the 152kg difference in motor weights would therefore allow the electric airframe to include the equivalent of 21kg of petrol.
That'd be enough for a short flight, but leaves you around 130kg short of the full-tank capacity of a typical GA single engine aircraft, and as soon as you start adding more battery capacity to increase range, you're immediately on the slippery slope caused by that 7.2:1 ratio in effective energy densities such that it doesn't take long before you hit the crossover point where the overall airframe mass is equal for the same range, and any additional increase in required range will then favour the petrol engine. If you go all the way to the end of the slope so that your electric aircraft has the same energy capacity as the fully fuelled petrol equivalent, then it'd be around 800kg heavier, at which point it probably isn't even going to get off the ground... And even if it did, it still wouldn't have the same range capability as the petrol aircraft, due to the additional penalty of having to lug around all that extra weight for the entire duration of the flight.
So yes, electric propulsion can be beneficial in some specific use-cases, but as a generic alternative to liquid-fuelled aero engines, there's still quite some way to go there.
Aviation fuel is very very expensive, and piston engines in those small planes require a lot more maintenance than an electric motor. Even if you have to expend more energy per flown mile if the electric version wins in cost to operate per flown mile it would quickly become very popular in that market.
finding a recharging point for your light plane while you're up in the air
There are just as many airborne recharging points for light planes as there are airborne refueling points for light planes.
That's why a lot more training is required to become a pilot than to get a license to drive a car, and among the things they train on is knowing what your range is and making sure you have some reserve for your planned route.
Thanks for adding in some numbers.
I think it makes sense that 500 Wh/kg battery is seen as a breakthrough for planes exactly in the sense that you can start designing/building a competitive small aeroplane. The bigger the airplane requirements, the higher that battery density has to be. But the jet fuel numbers aren't going to change, while the battery energy density will continue to creep up (based on numbers I saw yesterday, theoretically to well over 1000 Wh/kg but expected in practice to top out around 1000 Wh/kg).
Given the limitations, it's likely that there is a certain size beyond which electric aircraft would never be energy-competitive with jet aircraft. BUT as I have seen other commentors mention, cheaper batteries and electricity combined with simpler-maintenance electric motors vs more expensive jets/piston-engined planes and jet fuel might result in battery planes which are cheaper per passenger-km (at least for shorter flights)
Also combine that with the possibility (given less pollution and noise) for small central airports such as London City operating electric-only flights
I totally believe it.
I'm expecting to see this revolutionary communist top-of-the-line, bleeding edge tech any time now. Because surely, if they've announced it, it has to be true, right ? I mean, nobody has ever taken the risk of publicly announcing something that was factually incorrect, right ? Naahh.
Totally believe it.
And it's opposite day today.
"expecting to see this revolutionary communist top-of-the-line, bleeding edge tech any time now. Because surely, if they've announced it, it has to be true, right ?"
Surely your skepticism to "if they've announced it, it has to be true" isn't limited to revolutionary communist top-of-the-line, bleeding edge tech, but also extends to revolutionary capitalist top-of-the-line, bleeding edge tech?? I mean, in the end, is there any difference between "propaganda" and "marketing"?
Electric power aircraft are far off in the distance. If cars, trucks and trains were electrified first, the fuel aircraft are burning is less of an issue. A 500Wh/kg rechargeable battery in a car would mean the same range with much lower weight leading to better efficiency. The same for HGV's and it would start to be very viable to add battery tender cars to trains (trams, trollies, etc) to make it easy to bridge gaps where overhead lines aren't feasible like in low tunnels and complex stations.
As an aside, a company is proposing to add a train service in California between Los Angeles and San Francisco (likely Emeryville east of SF) using the coastal tracks Amtrak uses for the once a day Coast Starlight train (16 hour schedule). The new service would be a sleeper service that departs LA at 10pm to arrive in SF at 8:30am so it would be going around 50mph. I didn't see mention of the schedule for service going the other way. It would be nice to see that route be electrified and used more often so the cost can be amortized. I've been banging on about more overnight trains in the US for ages now. Rather than battle lines and indignities at airports, it would be good to travel while asleep (I sleep well on trains). It takes longer than booking one of the 50+ flights there are between the cities daily, but flying is one hour in the air and 4-5 of everything else that isn't putting miles towards the destination. The distance is likely about the minimum viable distance for electric airplanes since people often find it easier to drive between point closer to save time. This means that even a 'slow' train service can be a better alternative to electric planes given the right set of assumptions.
Crazy, the distance is ~650km.
A current high speed train could do that in 3 hours - competitive with the plane given all the faffing around at airports as you point out.
And with a much higher density of around 800 to 1000 passengers per train.
And a much higher frequency - you can do at least 4 trains per hour if not more.
Not forgetting the added bonus of not being in a plane.
However, an overnight sleeper does have its charms, though usually at a price.
The price of a sleeper is because you can fit much less people in sleeping compartments than seated (around half at most??). But it's also counterbalanced by the fact that for most trips of that length, you would anyway need to get an extra night at a hotel if you don't get the sleeper train - I find that the savings of a hotel night usually more than counterbalances the extra cost of the sleeper.
And the savings on time is extraordinary - what cost an extra 4-6 hours??
"A current high speed train could do that in 3 hours - competitive with the plane given all the faffing around at airports as you point out."
California is still flushing money down that particular toilet. The issue is terrain and that California has a major fault line running N/S that is a serious problem. What still hasn't been figured out is getting from the central valley to the Los Angeles basin. I think the route they want to go with takes the train over the Tehachapi mountains where there is already a freight rail line and the "Tehachapi Loop" (look it up, it's some interesting problem solving). Some of that trackage would need to be shared as there isn't room to add a parallel right of way. It also descends into the Antelope Valley about 150miles north of LA. There is a commuter train there that goes into the city, but it goes through several tunnels that would need to be modified for an electric HST. For a good portion of the route where they are wasting billions of taxpayer dollars in kickbacks and fraud is getting built. They just haven't figured out the hard bits. There is also already Amtrak service through the CA central valley that might be cheaper to modify for fewer level crossings and better dedicated track for higher speeds (120km or maybe a bit faster).
In the US the only really viable HSR is for long routes with few intermediate stops that are also serviced by feeder rail line, airports and inexpensive long term secure parking (with slow EV charging). With modern communications, the need to travel long distance in minimum time is more for pleasure than business so less contribution to GDP outside of the travel itself. I mention that as all of these sorts of projects come at great taxpayer expense. I'd still like to see more trains as air travel gets more and more expensive. Modern electric trains are incredibly efficient.
Assuming different products I imagine the technology is near identical.
At 500wh the Amprius quote C/10 for both discharge and charge and a lifespan of 200 to 1200 cycles.
In full solid state lifespan is the major problem so these will be problematic too.
However, in micromobility they look great, especially if fully safe too. 250 watt EU ebikes would certainly benefit from a 2.5kw/h pack weighing the same as a current 750 watt pack.
There seems to be a lot of news articles where experts deny claims made by China or other countries based outside of the United States and western allies. I remember a time when instead of denying those claims, we emphasized the progress of our own research and capabilities.
With the claim also backed up by promising production this year, I'm more inclined to believe than I would if there was just a claim they've done it in the lab and more work is needed. This is bad news for Tesla and their projects to bring battery production fully in-house. Other auto makers that aren't tied to long term contracts or gobs of capital equipment for making cells will have the ability to adopt these new cells as soon as there is volume production. Tesla can do the same, but it means trashing what they've already done towards making their own.
"Possibly, but it also shows them a way forward... "if they can do it so can we"."
There isn't always more than one way to skin a cat as the saying goes and I'd expect the new cells will be coated in patents. Perhaps Tesla can see what they've done and find a way to match them, but it takes time and investment and may obsolete a bunch of capital equipment they already own in addition to playing catch up with their competitors. If it means a delay of 6 months, GM may have already transitioned several of their models to the new cells and have them coming off the production line.
I do see value in vertical integration for some things, but it's not a universal solvent and holds traps for the unwary. When I had a manufacturing company, we used some outside machine shops for some of out parts. We looked into buying CNC lathes and all of the needed surrounding equipment, but found that it would tie up way too much capital until we hit certain volumes. I had all of those calculations on a spreadsheet and would dust it off from time to time and update the numbers, but we never got there before I had to close up the business. There were lots of benefits to bringing that work in-house, but the financial considerations were a huge roadblock.
"You mean it contains solids or liquids, just like every other battery every made?"
Marketing people make shit up all of the time and "Condensed Matter Technology" sounds really great without saying anything or treading into legally or ethically false descriptives.
I've worked at companies where the marketing dweebs would ask the engineers for something to put into press releases. Lots of beer was involved with those meetings amongst the engineering staff late on a Friday night. Corporate was impressed, but we never got credit or the cost of the beer reimbursed.
still have the lead IMO. Aluminum-ion graphene batteries are going into production later this year with 3 times the energy density of lithium with none of the chemical or moral drawbacks. Once they're being installed, and I can rely on being able to charge anywhere I need to, I'll make the conversion. Sadly only 300wh/kg at the moment, but they're improving.
Thumbs up for GMG, I'm also following their progress with interest. AFAIK the bottleneck is volume production of graphene for the anodes, combined with automated / semi-automated production. I believe they are assembling pouch cells mostly by hand though they should be starting this year the automatic manufacturing of button cell batteries.
In any case 300Wh/kg is nothing to sneeze at if they can get the manufacturing process going, since Al is much more plentiful and cheap than Li, so could keep costs down. Also, if their claimed longevity (2,000 charging cycles with no significant degradation) turns out to hold in real life. 300Wh/kg might not be sufficient for aircraft, but a not-too-expensive and long-lasting battery of that density means you can shave 100-200 kg off the half-tonne battery mass in current long-range cars while still keeping or increasing the range, or go all-out for an ultra-long-range car (500kg > 150kWh X 5,5km/kWh = 825km range)
Everyone seems to be treating it as an either / or.
One use case for electric motors in airliners is getting the aircraft from the ramp to the runway - by driving the wheels directly. Which would save on fuel and dispense with the need for a tug to back the aircraft away from the gate.
Another use case is to provide additional thrust during take-off / go-around, allowing smaller, lighter turbines to take care of everything once over 200 knots or so.
I just can't keep up with it all. What I know is my rubber band powered balsa aircraft has around 30 turns to get it flying - which keeps it airborne for 30 seconds and allows it to fly in a loop.
Crossing the ocean will take considerably more turns and will probably result in structural failure.
Anyway it's Friday so good luck with it all.
This whole thing is ridiculous, from the concept to the claims. There is no point in fitting batteries to commercial aircraft unless there's a 1000x increase in energy density. There are no problems lifting significant weight off a runway (eg even a 787 can stagger into the air at more than 250 tonnes), but you can't *land* at that weight. Don't forget that you'll need ~1MW continuously for air conditioning / pressurisation, hydraulic motor pumps, in-flight entertainment, flight computers, pilots' heated seats, ovens etc etc.
Far, FAR better accept that aviation will need to use hydrocarbon fuels and instead to concentrate on minimising the environmental impact from aviation by carbon capture and carbon-neutral fuel production.
The max take off Max landing weight issue is exaggerated - it is certainly a factor for really big, really long range aircraft such as an A380, but for a short haul turboprop the two are usually the same. Obviously if you expect to fly 10 hours you can factor fuel burn in your design, if you expect to fly 45 minutes you don't.
A Fokker f50 carries 58 passengers and about 1500 kgs of fuel. An electric motor is probably about twice as efficient as a jet turbine, and the fuel for the jet 20 times as energy dense as these batteries. So roughly that balances out as 10 times less fuel/weight per mile for the electric option. Granted that means you would need pretty much all your load capacity and a bit more to match a Fokker's 3500 kilometer range. But equally you might mage a half load of passengers over 1500 kilometrers, which would cover a lot of short haul flights. the 350 kilometers London to Amsterdam could be viable with about 35 passengers,, and over those distances, no ovens, no inflight entertainment, give the pilots blankets to keep their seats warm etc...
Not saying its realistic tomorrow, but you can see we are getting closer....Too often El Reg falls back on the old EV 'but I commute 500 miles each way towing a trailer full of depleted Uranium every day so UI cant use an EV therefore all Evs are rubbish' argument
"Far, FAR better accept that aviation will need to use hydrocarbon fuels and instead to concentrate on minimising the environmental impact from aviation by carbon capture and carbon-neutral fuel production."
Such nice buzzwords you have. It would be a shame if anything happened to them.
The US had a coal power plant with carbon-capture... That didn't work out so well. Speaking of wells, pumping CO2 down old wells has been tried and they've found a new way to discover old wells with insufficient plugs. A Carbon-Neutral fuel would be amazing depending on how you calculate the 'neutral' part.
It makes little sense to burn vast amounts of money trying to develop Silver bullets. The low hanging fruit right now is personal and cargo transport and there are many different ways to make improvements using technology that's already around. If governments are mandating/subsidizing which one will be the best and therefore the only one that will be allowed, perhaps there would be more progress made. In fact, governments could take some lead. In the US there are vast numbers of 'government' vehicles and effectively zero BEV's among them. If they would prod Ford or GM to build a useful vehicle that meets certain criteria and dispenses with all of the fluff, they could set a precedent without giving away money in subsidies to their chosen 'winners'. The Ford Crown Victoria and Taurus sedan were fleet models. The Taurus went on to do pretty well as a production car for general sale. The Crown Vics got snapped up by taxi companies when the police departments were done with them as they're built like a tank. In my general area there are something like 8 or 9 welfare offices with varying signage and they all have cars parked in from with exempt plates on them. I doubt they're going on long trips, need race car acceleration or 27 speaker entertainment systems. Why not an EV that has none of that and won't be future compatible with automated driving at some point in the future when the software is sorted. That should save a stack of bank notes and a couple hundred kg of mass.
According to the Wiki EE are now fuelpositive.com having switched to green Ammonia from 700w/h kg solid battery cells.
In their reason to invest they say 'Once we have completed the full validation in our facility, we will have two third-parties – a university and an accredited lab – conduct independent validations before the system will be moved to the farm.'
Something different, yet a similar story. Maybe.
"having switched to green Ammonia "
Green Ammonia would be good in the US and a great use of wind turbines. There is a network of underground Ammonia pipelines in the US (Call before you dig). Plant a turbine next to one, pipe in some water and drop off a Haber/Bosch cell in a shipping container with the output fed into one of those pipelines. The intermittency of the wind is less of an issue compared to hooking the turbine into the grid and Ammonia production is one of the largest users of electricity in the US so win-win. I've over simplified, but I've seen some work done on this and it makes sense. I'm not convinced that an Ammonia fuel for aircraft is a good choice. It's nasty stuff. I'm not using kerosene as a cologne, but at least the smell won't burn my sinuses out and cause vision problems. There are other fuels that can use Ammonia as a feed chemical. I'm not sure if any of those is viable for aircraft use.
In an article from 2016 https://aerospaceamerica.aiaa.org/features/the-buzz-over-batteries
The most advanced aviation batteries such as those powering small drones, have an energy density of 500 watt-hours per kilogram.
Just last tear from Japan https://www.sciencedaily.com/releases/2022/01/220120140724.htm
About the development of a lithium-air battery with an energy density over 500 wh/kg
"Anything you hear from Chinese is going to come from their Ministry of BS Propaganda. "
In aerospace the tell-tale that a technology isn't close is when a company says that something will be coming out in two years. When you hear "two years", that tells you that investing in that company is premature if you aren't a risk junky.
OTOH, saying that something is due in production in the third quarter and it's the second quarter is usually a good indicator that it IS real and the production lines are being built.
The Register 
Biting the hand that feeds IT
Copyright. All rights reserved © 1998–2024
