Ford and Purdue develop new EV charging cables

[tangoseal]

Considering a 30kV power cable is what? 1000amp max for a daily load? The physics portion of my brain is going "NOPE NOPE NOPE" the first time I see one of these being used.

Would love to see how they did this. Still terrifying though.

Voltage doesnt matter for a cables amperage rating.

You can have speaker wire rated for 10 amps current and put 2 million volts through it as long as the curent draw of the load doesnt exceed the cables 10 amp rating. Or you can put 1v at 10 amps and its all the same to the cable.

However, the diaelectric properties of speaker wire insulation will protect you all day long up to its rated value, say 300v, but 2,000,000v would jump through it and smoke your ass. But that has nothing to do with load ratings of cables. It was just a fun fact.

There really isnt any physics to consider except a few formula to help understand.

V=I/R
Voltage=current÷resistance
And algebra around that all day.
Also things like type of power matters since were talking DC and not AC it is preferrable to use thick solid cables over stranded. Dc uses the width of the conduxtor whilst ac uaes the outer skin of the conductor.

However a cable that can support 2500 amps has to be made from exotics and has to be flexible so it is interesting to see the metallurgy they used.

 

[Nafensoriel]

Voltage doesnt matter for a cables amperage rating.

You can have speaker wire rated for 10 amps current and put 2 million volts through it as long as the curent draw of the load doesnt exceed the cables 10 amp rating. Or you can put 1v at 10 amps and its all the same to the cable.

However, the diaelectric properties of speaker wire insulation will protect you all day long up to its rated value, say 300v, but 2,000,000v would jump through it and smoke your ass. But that has nothing to do with load ratings of cables. It was just a fun fact.

There really isnt any physics to consider except a few formula to help understand.

V=I/R
Voltage=current÷resistance
And algebra around that all day.
Also things like type of power matters since were talking DC and not AC it is preferrable to use thick solid cables over stranded. Dc uses the width of the conduxtor whilst ac uaes the outer skin of the conductor.

However a cable that can support 2500 amps has to be made from exotics and has to be flexible so it is interesting to see the metallurgy they used.

I was more speaking about the most robust cable I personally have seen and had access to not being in the realm of handling 2500amps without failure.
I personally have seen "pet projects" trying to do things like this with liquid gold inside carbon tubes. While that works the loss rate due to liquid metal and the sketchy conditioning phase that doesn't handle failure or shutdown well left them as just pet projects of the "Hey... I made a cable out of gold and diamonds!" kinda thing.

The OPs solution is elegant from an engineering standpoint and actually pretty safe. Because it is actively cooled you don't really need absurd exotics and can integrate safety features to mitigate the worst types of failure. The joke you missed was pointing out the challenges. With this project you have kilovolts and high amps in the same system. KV+Amps with any form of significant resistance is explosive at worst and very thermally excitable at best. That isnt even considering what happens if the insulation fails while there is still current in play. They are intentionally using smaller cables than typically used and bypassing the resistive effects with cooling to make the whole system more efficient and functional.

Their challenges are a laundry list of catastrophics that could be really terrifying when you throw the general public into the mix. The risk assessment process for deploying these things would require a lawyer(this is a joke).

To put this into perspective with a gasoline car you dont really have that much risk at the pump. The design elements of the fueling system, gas tank, and pump system are heavily engineered to prevent you from exposure to risk. As long as you follow extremely basic "stick dick into hole" engineering your personal risk is effectively zero. To get there though they had to consider all forms of benzine and toluene exposures, ignition risks, environmental damage over time due to microspills, user error, atmospheric sparking due to low humidity, etc...
This cable is a different beast mostly dealing with the above mentioned high voltage+high amps=bomb factor and the potential of this current to have some fun electromagnetic and arcing effects.
The "nope nope nope" is due to the risk factor for this cable including a reality where I and anyone within 10 feet of me is potentially dead before anyone even knows there was a problem.
Watch a high voltage switch at a power plant arc and realize this cable is talking about putting that level of current in the palm of your hands.

This is a grid level application reduced to 5 minute charging cycles in the 80 to 160kWh range. That's nearly three to six times the power your house uses per day in five minutes.

 

[NightReaver]

Correct me if Im wrong, but isn't excessively quick charging harsher on existing batteries? What would 5 min charging cycles do to them?

 

[cdabc123]

Correct me if Im wrong, but isn't excessively quick charging harsher on existing batteries? What would 5 min charging cycles do to them?

You can't charge them in 5 min. Those battery cells have a finite max charging current and this would go way beyond that for current battery configurations.

 

[N4CR]

Open pit mining for everyone! It'll make fracking look cuddly.

Fracking is cuddly until a pipe casing goes and the toxic muck or oil gets into your ground water.

Back in the early 80's I was working on a speed modification for a Philips Laser Disc player. These players used a helium-neon laser so the power supply output was around 20kV. Getting zapped by that was an experience! I could taste my metal fillings, but luckily didn't otherwise hurt myself.

Are you Steve/Mixedgas?

 

[sfsuphysics]

Lord 2500 amps....if something goes wrong you won't have a car left.

I would imagine that EV cars could somewhat simply just have a sacrificial hunk of frame attached to a wire that you'd hook up to ground in case there was a short somewhere between the electrics and the frame of the car, could also just have it built into the charging station too, but then they'd need two of these mythical 2500A capacity wires.

 

[sadsteve]

Fracking is cuddly until a pipe casing goes and the toxic muck or oil gets into your ground water.

Are you Steve/Mixedgas?

Nope

 

[Nafensoriel]

Correct me if Im wrong, but isn't excessively quick charging harsher on existing batteries? What would 5 min charging cycles do to them?

Currently used cells are not capable of 5-minute charging. There are physical restrictions in play with their design. One of the worst is needing to be at 60c for optimal charging.
There are cells that can be charged in 5 minutes in preproduction or in labs. Lab batts pretty much can do whatever magical thing you want but rarely do these effects go beyond button cell size and almost never enter actual production.

There are technologies, like supercaps, which are being dusted off and improved which can be charged rapidly and can function inside an EV.
While LiFePO4 is what I consider a dead-end technology they are by no means the only technology in the game.

 

[Wade88]

Fracking is cuddly until a pipe casing goes and the toxic muck or oil gets into your ground water.

Are you Steve/Mixedgas?

It's satire, everyone else got this but you. gg.

 

[Krenum]

Great! But if you think electricity is "cheap" you're sadly mistaking. When and if EV's become as common as combustion engines, you're going to be playing exactly the same or probably more for making your vehicle move than you are now. Don't let anyone tell you that EV's are cheaper, they are not.

The tax man cometh.

 

[cpufrost]

Great! But if you think electricity is "cheap" you're sadly mistaking. When and if EV's become as common as combustion engines, you're going to be playing exactly the same or probably more for making your vehicle move than you are now. Don't let anyone tell you that EV's are cheaper, they are not.

The tax man cometh.

Exactly this! When electric demand soars so will the bills. Actual rates lag due to regulations but the distribution surcharges go through the roof. Hello .35 per kWh (actual). Which is pretty bad. We have about 350kW of solar on the lands (grid tie) and it helps tremendously when we over generate and get credits which will increase as well. We are looking into electric ATVs and even dirt bikes to replace our ICE ones. And without getting too much into a political debate, the per mile charges coming due to the reduced income from lack of petrol road tax revenue.

 

[Nafensoriel]

Great! But if you think electricity is "cheap" you're sadly mistaking. When and if EV's become as common as combustion engines, you're going to be playing exactly the same or probably more for making your vehicle move than you are now. Don't let anyone tell you that EV's are cheaper, they are not.

The tax man cometh.

Idiots think EV means cheap because power is cheap.
Smart people think EV is cheap due to basically zero maintenance compared to ICE, especially for larger vehicles.

While demand soars so can supply though. A handful of nuclear power plants pretty much erases the cost concern for "fuel"... and no nuclear is not "super expensive". It hasn't been for decades.

 

[NightReaver]

A handful of nuclear power plants pretty much erases the cost concern for "fuel"... and no nuclear is not "super expensive". It hasn't been for decades.

While true, as mentioned in previous EV threads, the people who push EVs are usually anti nuclear at the same time.

 

[Nafensoriel]

While true, as mentioned in previous EV threads, the people who push EVs are usually anti nuclear at the same time.

Whelp can't fix stupid I can be a stubborn old bastard and outlive their kale smoothy arses.

 

[GreenLaser]

The only way i see this EV stuff scaling up successfully is that each "Charging Station" has a giant supercapacitor inside that can dump into a car quickly then SLOWLY recharge in off peak hours. Your backyard solar panels and windmills could also be supplemental.

What irks me most in this entire discussion is the complete ignorance or outright dishonesty being uses to shill for it. The attractiveness of a perfectly quiet vehicle with no apparent emissions sounds like a no brainer to the blissfully ignorant. The dishonesty comes when we try to ignore the layers upon layers of technical and physical inefficiencies needed to support this crystalline vision of the perfectly pure zero emissions vehicle.

Any rational person when shown the piles of wires, batteries, supercapacitors and electronic gadgetry to make an EV go 100 miles and then compare that with a small metal can full of fuel that can do the same thing will instinctively see there also must be a complexity/cost differential. That dishonesty is also artificially driving up ICE fuel costs and camouflaging it with inflation. Nobody wants EV to disappear and i actually like the additional choices it brings but please stop peeing on my leg and telling me its raining.

 

[sfsuphysics]

The only way i see this EV stuff scaling up successfully is that each "Charging Station" has a giant supercapacitor inside that can dump into a car quickly then SLOWLY recharge in off peak hours.

Since this thread is about pushing mucho amounts of current (and presumably power) I think you're onto something, just a bit backwards. Charge up a super capacitor on the vehicle super quickly, then that can slowly charge up the battery at a rate that doesn't prematurely damage the battery (much).

Now while this idea is totally fine and dandy, last I checked super capacitors are at least an order of magnitude lower than lithium batteries in energy density per mass, so unless something big happens there... yeah not going to work either.

That said, if someone made fast charging batteries, the idea of the super capacitor to charge up with whatever your service can dump on it like it's a secondary fuel tank is good too, but again some technology is needed to make it work one way or another.

 

[cpufrost]

Super caps can help with brief inrush currents to protect the distribution systems from dips and overloads. Much as car audio guys put them right on the amp terminals to keep the amp source from dipping under bass drum kicks. The cap impedance is much lower than ten feet of 1/0 wire.

Speaking of car audio, EV opens up a huge opportunity for truly high power systems without the need for multiple 1000 kcmil wires running everywhere! I was a SQ guy back in the 80s and 90s but now all it seems as you have vans full of 18s and some random easy on the eyes chick with long blonde hair looking like she's sitting on a big Van De Graaf generator cranked up to 10 million volts while some crappy sounding beats are playing loud enough to be felt in the next county!

 

[tangoseal]

Super caps can help with brief inrush currents to protect the distribution systems from dips and overloads. Much as car audio guys put them right on the amp terminals to keep the amp source from dipping under bass drum kicks. The cap impedance is much lower than ten feet of 1/0 wire.

Speaking of car audio, EV opens up a huge opportunity for truly high power systems without the need for multiple 1000 kcmil wires running everywhere! I was a SQ guy back in the 80s and 90s but now all it seems as you have vans full of 18s and some random easy on the eyes chick with long blonde hair looking like she's sitting on a big Van De Graaf generator cranked up to 10 million volts while some crappy sounding beats are playing loud enough to be felt in the next county!

Until a cap comes unwound. That is a site to behold especially after you get your medical bill.

In Amateur radio mobile setups where we have 80 to 120 amp 12v transistor based HF amplifiers, it is frowned upon to use caps due to the inherently dangerous unwinding events that can occur. However I would think a high level manufactured capacitor by say, Tesla, would be far more robust than what is offered on the shelves of Bestbuy.

 

[Nafensoriel]

Since this thread is about pushing mucho amounts of current (and presumably power) I think you're onto something, just a bit backwards. Charge up a super capacitor on the vehicle super quickly, then that can slowly charge up the battery at a rate that doesn't prematurely damage the battery (much).

Now while this idea is totally fine and dandy, last I checked super capacitors are at least an order of magnitude lower than lithium batteries in energy density per mass, so unless something big happens there... yeah not going to work either.

That said, if someone made fast charging batteries, the idea of the super capacitor to charge up with whatever your service can dump on it like it's a secondary fuel tank is good too, but again some technology is needed to make it work one way or another.

Super(ultra)caps are around 5 times less energy-dense per kg right now.
The maximum lab-tested supercap is 90ishWh/kg which is damn close to what LiFePO4 can do... and it was more in the realm of possibility than most Li-ions lab batts.
The issue is while Li-ion can theoretically top out at 250ish Wh/kg and possibly with fairy dust get to 460 Wh/kg a supercap can theoretically exceed 1000Wh/kg. Gasoline is 12000ish Wh/kg

While it seems absurd getting to that 1:24 or 1:12 ratio with an EV puts it on par with a gasoline vehicle due to the different configurations of the car(not needing transmissions etc).

This doesn't even count the safety advantages of supercaps, their charge rate maximums, and the fact that you can 3D print them.

tangoseal
Supercaps don't fail like caps. When a supercap fails it typically just stops working. Most of them don't even require a major risk assessment for use because of their near lack of catastrophic failure modes. In comparison, many sites don't even let Li-ion on-site without it being intrinsically safe.

 

[GreenLaser]

Since this thread is about pushing mucho amounts of current (and presumably power) I think you're onto something, just a bit backwards. Charge up a super capacitor on the vehicle super quickly, then that can slowly charge up the battery at a rate that doesn't prematurely damage the battery (much).

Now while this idea is totally fine and dandy, last I checked super capacitors are at least an order of magnitude lower than lithium batteries in energy density per mass, so unless something big happens there... yeah not going to work either.

That said, if someone made fast charging batteries, the idea of the super capacitor to charge up with whatever your service can dump on it like it's a secondary fuel tank is good too, but again some technology is needed to make it work one way or another.

I don't see a need to carry supercaps on vehicle. I'm thinking a supercapacitor "box" the size of a refrigerator in a persons garage able to store enough electrons to feed one or two vehicles completely off the grid if necessary. The charging of the supercap could be offset to off peak hours and also at a much slower rate overnight negating power cabling upgrades at the street level.

When i was a kid we had tiny electric racing cars called "Sizzlers". The charger looked like a gas pump with large D batteries inside. Same concept to decouple the massive amperage charging operation from the grid and NOT use expensive batteries for the intermediate storage.

 

[Not_Me]

I don't see a need to carry supercaps on vehicle. I'm thinking a supercapacitor "box" the size of a refrigerator in a persons garage able to store enough electrons to feed one or two vehicles completely off the grid if necessary. The charging of the supercap could be offset to off peak hours and also at a much slower rate overnight negating power cabling upgrades at the street level.

When i was a kid we had tiny electric racing cars called "Sizzlers". The charger looked like a gas pump with large D batteries inside. Same concept to decouple the massive amperage charging operation from the grid and NOT use expensive batteries for the intermediate storage.

View attachment 413838

WOW!? I had to look this up. I have never heard of sizzlers. I had hot wheels & match box and slot race track but rechargeable cars in 1971? Even rechargeable flash lights and razors were rare back then.

 

[sfsuphysics]

I don't see a need to carry supercaps on vehicle. I'm thinking a supercapacitor "box" the size of a refrigerator in a persons garage able to store enough electrons to feed one or two vehicles completely off the grid if necessary. The charging of the supercap could be offset to off peak hours and also at a much slower rate overnight negating power cabling upgrades at the street level.

But how is a supercap fundamentally different than a battery in this case? Sure you could argue that they can discharge current at might higher rates, but discharge it where? Into another battery, so you still limited by the charging rates of a battery and really aren't gaining anything from using a supercap over just having a battery bank. That said, if you are parking in your garage I believe Tesla allows you to wait until off-peak times to charge, I forget if it needed the Powerwall to do this or not.

The idea of putting supercaps on a vehicle was that if charging at insanity levels of current became the norm you'd have a buffer to accept the charge and discharge it at a rate to save your battery

 

[serpretetsky]

But how is a supercap fundamentally different than a battery in this case? Sure you could argue that they can discharge current at might higher rates, but discharge it where? Into another battery, so you still limited by the charging rates of a battery and really aren't gaining anything from using a supercap over just having a battery bank. That said, if you are parking in your garage I believe Tesla allows you to wait until off-peak times to charge, I forget if it needed the Powerwall to do this or not.

The idea of putting supercaps on a vehicle was that if charging at insanity levels of current became the norm you'd have a buffer to accept the charge and discharge it at a rate to save your battery

Yeah neither case really makes much sense to me.

Supercaps at the charging station: like you say, still need to slowly discharge into battery. One pro might be that you can buffer the electric grid better. But on a larger scale I dont think it matters much.

Supercaps in the EV: Supercap energy density is abysmal compared to batteries. If you somehow have enough supercaps to fully buffer and charge the batteries then why do you have the batteries to begin with? If you have supercaps that can only hold about 10% the energy of the batteries (much more likely) then it really doesn't help that much anyways. You can charge that 10% superfast, but then your still stuck trying to charge up the actual batteries which hold most of the energy.

The extra complexity and cost for either of these situations doesn't seem worth it to me (just by judgement, not having done any actual estimates/math)

 

[Nafensoriel]

The only reason to do Grid>Cap>cap is to limit the investment needed in grid upgrades.

Most fuel service times fall in very narrow bands of time. There is no point upgrading the grid if you can replace underground liquid tanks with underground supercaps that do essentially the exact same thing.
The "fuel station" only needs enough fuel on hand to handle the days load or whatever timeframe the delivery process is. Anything less is inefficient.

Why you want supercaps in a vehicle is pretty simple. They are cheaper, can be 3d printed, do not explode, and can be charged in a similar time frame to a gasoline vehicle.
Batteries cannot match this performance in the typical usage case for a car. A battery has advantages but if it is a daily use vehicle a supercap is superior in function.

serpretetsky Right now supercaps are capable of matching midtier lithium cells. Unlike lithium cells, this advancement can be rolled into production without scaling issues. Supercaps are viable right now but the lead time is now in engineering their actual use in a practical application. Just because you have a thing doesn't mean you can suddenly slap it into a preexisting vehicle. Additionally, supercaps only make sense once we truly start shifting the grid to charging EVs. They are the eventual path that will be taken. LiFePO4 isn't viable for general use for the greater population.

Supercaps are also ridiculously easier to design for. As mentioned you can 3d print them and they have no catastrophic failure modes.

 

[serpretetsky]

serpretetsky Right now supercaps are capable of matching midtier lithium cells.

Already in production? link?

 

[Lakados]

Already in production? link?

Supercapacitors are used in large industrial electric vehicles like massive dump trucks used on mining sites because they can be perpetually charged via their regenerative braking and the weight difference isn't a factor and neither is the range for the most part. Supercapacitors have 1/10'th the storage capacity of modern Lithium-Ion battery packs. Graphene tech can supposedly vault supercapacitors well ahead but that costs big money and isn't feasible outside of a lab at this point. It is heavily being looked at though and in another 10 years, I can easily see it coming along but right now not a chance.

 

[serpretetsky]

Supercapacitors are used in large industrial electric vehicles like massive dump trucks used on mining sites because they can be perpetually charged via their regenerative braking and the weight difference isn't a factor and neither is the range for the most part. Supercapacitors have 1/10'th the storage capacity of modern Lithium-Ion battery packs. Graphene tech can supposedly vault supercapacitors well ahead but that costs big money and isn't feasible outside of a lab at this point. It is heavily being looked at though and in another 10 years, I can easily see it coming along but right now not a chance.

Good to know about the dump drunks. Seems like a good use-case. And generally agreed with your assessment, although I think even saying that supercaps are 1/10th storage capacity of modern battery packs is optimistic for current supercaps and current batteries.

https://newatlas.com/energy/superca...power densities around 10 kilowatts per liter.

Even lab research supercaps using graphene (not production) in 2020 were only competing with lead acid batteries, and not even lithium based batteries.

 

[Lakados]

Good to know about the dump drunks. Seems like a good use-case. And generally agreed with your assessment, although I think even saying that supercaps are 1/10th storage capacity of modern battery packs is optimistic for current supercaps and current batteries.

https://newatlas.com/energy/supercapacitor-density-breakthrough/#:~:text=That figure is toward the high end of,massive power densities around 10 kilowatts per liter.

Even lab research supercaps using graphene (not production) in 2020 were only competing with lead acid batteries, and not even lithium based batteries.

The numbers may have been for new proposed supercaps vs batteries or they may have just been comparing their stored energy differently.
Found this on a different site from 2020 which shows the Wh storage even worse than that.

In either event it’s going to be a while before supercaps become viable for the general public. But they could possibly be used in conjunction with a lithium ion battery pack, supercharge the capacitor and have that trickle down to the batteries. We can have hybrid power trains why not hybrid battery packs?

 

[Nafensoriel]

Supercapacitors are used in large industrial electric vehicles like massive dump trucks used on mining sites because they can be perpetually charged via their regenerative braking and the weight difference isn't a factor and neither is the range for the most part. Supercapacitors have 1/10'th the storage capacity of modern Lithium-Ion battery packs. Graphene tech can supposedly vault supercapacitors well ahead but that costs big money and isn't feasible outside of a lab at this point. It is heavily being looked at though and in another 10 years, I can easily see it coming along but right now not a chance.

Correct. In industrial applications, we are already seeing or have on order parts that are lab listed at 350Wh/kg range(will explain this later). Nanoramics is pretty much the cutting edge at the moment.
Capacity 10 years ago was around 1Wh/kg. Today commercially available supercaps are 20-55wh/kg or on par with higher-end lead-acid. (typical lithium is 80-120 wh/kg)
Lab condition caps are in excess of 350wh/kg (practical usage of these cells is expected to be 60-90wh/kg)

The difference in comparison of lab caps vs lab batts is that LiFePO4(lithium modern cell) advancements typically require very precise construction and structure to reach significantly different numbers. This precision makes any of these advancements decades behind practicality at best and impossible at worst. For lab caps, the inherent design doesn't really care about size since it is functionally a simple structure repeated. Seriously an ELDC(supercap) is basically thin layers of material. To make advancements you simply change the material and structure of the "tape". Because of this, the iteration rate is rapid and far far easier. If you see nanoramics say they have a product then they can SELL that product in years not decades. Considering rolling a new technology into modern car manufacturing takes about 5 years you will start seeing capacitor technology in cars around 2025-2027. The first market is likely performance EV cars.

Downsides... Cost. It's expensive right now, especially on the engineering front. Caps don't really directly replace batteries. Their charge storage lifetime is a blink of an eye compared to Li-ion. The only way supercaps work is when most people are using EVs and charging them regularly is a common everyday occurrence. Leaving a supercap EV in your garage for the winter would drain the cell to empty where a lithium battery would store just fine for such a short period of time. The good news is the cost overrun is almost identical to how Li-ion was two decades ago with a similar trend in reduction. Once people figure out the chemistry for construction the technology is almost instantly scalable.

The Wh/kg listing has to be taken in context. When I say 350wh/kg there is an adjustment due to engineering designs when applied to practical usage cells. Think about it like hydrogen. Technically the best fuel source you can find short of antimatter or liquid metallic hydrogen. Hydrogen gas plus storage is the absolute worst in density to weight. While the actual "capacitor" is 350wh/kg the practical cell weight capacity is typically between 5 and 10 times less. I have to stress that this is disingenuous and must always be taken into context. supercaps do not require a shape to function properly. When they transition to car usage there will be custom blocks built just for them rather than the LiFePO4 cylinder cell method in use right now. You cannot take an industrial cells wh/kg and use it as a direct comparison. The curve for scaling capacity is also heavily in favor of caps since you do not need massive computer systems and heating/cooling systems to keep them from... well detonating.

-------------
TLDR extras
In practical application what the end point design will leverage both technologies but the lithium cells will not be exposed to the charging cycle. lithium(and batteries in general) do not lose the amount of work power(v) they apply over their charge life. The opposite is true for caps which are fairly linear in what they can supply vs what they are currently at charge-wise. Caps are at their best when you need a massive absurd amount of power suddenly... such as accelerating a car or quickly charging a car-sized fuel capacity. Batteries are at their best when the work they need to do is stable and constant. Hybrid structures for EVs is the natural evolution and where everyone and their brother is currently heading. It is the only way without a novel technology to do what is required to mass adopt EVs and handle them without fairy dust budgets and lifestyle changes.

Pure capacitor vehicles will be relegated to transport and local work vehicles or even simple short-range commuter vehicles. A mass-produced supercap is cheaper than any comparable Li-ion. The cost is only in the "new" bleeding edge. Think of a taxi service. Does a taxi need to really have a constant 600km range when it only ever takes short less than 75km trips? Wouldn't it be most cost-effective to design a lighter, safer, and more simple design that can be charged between stops?

 

[serpretetsky]

Today commercially available supercaps are 20-55wh/kg or on par with higher-end lead-acid.

I am genuinely curious about this. Do you have links to these? Everything I'm finding is less than 10wh/kg

 

[Lakados]

I am genuinely curious about this. Do you have links to these? Everything I'm finding is less than 10wh/kg

Look into Curved Graphine Ultracapacitors or Hybrid Ultracapacitors. Those can reach those sorts of densities
But most super or ultra capacitors currently available on the market look like these guys here which are still solid sells and represent a pretty big breakthrough in what is available out there.

But this here is a good read on the state of current graphene supercapacitor research. https://iopscience.iop.org/article/10.1088/1361-6528/aa8948/meta
The abstract tells you pretty much all you need to know

Supercapacitors, based on fast ion transportation, are specialized to provide high power, long stability, and efficient energy storage using highly porous electrode materials. However, their low energy density excludes them from many potential applications that require both high energy density and high power density performances. Using a scalable nanoporous graphene synthesis method involving an annealing process in hydrogen, here we show supercapacitors with highly porous graphene electrodes capable of achieving not only a high power density of 41 kW kg−1 and a Coulombic efficiency of 97.5%, but also a high energy density of 148.75 Wh kg−1. A high specific gravimetric and volumetric capacitance (306.03 F g−1 and 64.27 F cm−3) are demonstrated. The devices can retain almost 100% capacitance after 7000 charging/discharging cycles at a current density of 8 A g−1. The superior performance of supercapacitors is attributed to their ideal pore size, pore uniformity, and good ion accessibility of the synthesized graphene.

 

[cpufrost]

Wow that would make for some crazy super sub ohm vaping! ;-)

 

[serpretetsky]

Look into Curved Graphine Ultracapacitors or Hybrid Ultracapacitors. Those can reach those sorts of densities
But most super or ultra capacitors currently available on the market look like these guys here which are still solid sells and represent a pretty big breakthrough in what is available out there.

Yeah those skeletontech caps looks pretty good. Seems they are VERY new (are they even selling them yet?) I'm not too interested in research or lab conditions, more curious what someone can actually buy right now.
So how much does something like that cost?

 

[Lakados]

Yeah those skeletontech caps looks pretty good. Seems they are VERY new (are they even selling them yet?) I'm not too interested in research or lab conditions, more curious what someone can actually buy right now.
So how much does something like that cost?

They are selling them, those ones posted up there from Skelcap are supposedly used in the 3 Electric Busses that we just signed off on and should be here in July.

 

[serpretetsky]

They are selling them, those ones posted up there from Skelcap are supposedly used in the 3 Electric Busses that we just signed off on and should be here in July.

Not sure if you know, but even if you do know I imagine you probably cant give prices. But in terms of $ / energy, I assume they probably cost more than typical supercaps ?

 

[Lakados]

Not sure if you know, but even if you do know I imagine you probably cant give prices. But in terms of $ / energy, I assume they probably cost more than typical supercaps ?

I would have to assume so, but how much more compared to normal supercaps or battery packs I can't say (because I don't know not because of a gag order or something). The pricing sheets for my part of the decision making wasn't that detailed, for the bus purchase my part of that conversation was more about how I can pull the data from solar panels and cross-reference it against our diesel purchases for the past few years because we already know that the local "electric is fake and solar is a waste" crowd are gonna be all over us on this and we need to have our numbers front and center to keep them quiet. That and I had specific questions on the camera setup inside and out and blah blah blah because with the current busses I am the only one who seems to be able to pull dashcam and interior footage whenever there is an issue so my part focused around those topics. The battery tech was more our Mechanic who is not happy about this because he has no clue how to service these things but we all know he's looking to retire soon anyway and these things are fully enclosed and most of the problems in our existing fleet come from all the empty pockets under them that never get cleaned properly and corrode away. All the sales guy told him was something along the lines of how Lithium Ion burned too fast to give any evacuation time in the event of an accident so they are using these new german designed supercapacitors as they are lighter and offer more storage than the existing lead-based options, and that the power banks will likely outlive the busses themselves.

 

[Darunion]

Not sure if you know, but even if you do know I imagine you probably cant give prices. But in terms of $ / energy, I assume they probably cost more than typical supercaps ?

About 70ish bucks on digikey for the 3200F one

 

[serpretetsky]

About 70ish bucks on digikey for the 3200F one

I think you are referring to this one?
https://www.digikey.co.uk/en/products/detail/skeleton-technologies-gmbh/SKELCAP-SCA3200/13180992
I meant the high specific energy one. SCX5000
https://www.skeletontech.com/skelcap-scx-ultracapacitor-cells

But as an example lets use the one you found.

Lets pretend we want a 10 kwh battery (typical batteries on EVs are 40kwh to 100 kwh ).
Lets pretend we can get a price of 25$ per cell since we are tesla/GM/Nissan/Vokswagen/etc and we are going to be ordering hundreds of millions of them.

Using E= (1/2) (C) (V^2)
Using 1J = 0.00028 watt hours

Capacitor​	​
​	​
Inputs​	​
C per cell (F)​	3200​
Potential per cell (V)​	2.85​
Required total capacity (watt hours)​	10000​
price per cell:​	25​
mass per cell (kg)​	0.5​
​	​
Outputs​	​
E per cell (Joules)​	12996​
E per cell (watt hours)​	3.63888​
required number of cells​	2748.09831596535​
total cost for all cells​	68702.4578991338​
total mass for all cells​	1374.04915798268​

So lets compare to tesla S just using numbers I found searching internet:

Supercaps	1374kg	10kwh	$68 000
Tesla S battery	550kg	85kwh	less than $10 000

Obviously like others have mentioned supercaps have their applications. 30 seconds (or less even?) recharge time would be awesome for example. If someone finds the cost of those higher end caps i can redo the calculations. If future supercaps blast through these numbers that would be awesome, but there is a lot of catching up to do.

 

[Darunion]

serpretetsky oh for sure it isn't ready as a replacement. I do like how far it has come though.

Ah you are right it is a different series and I couldnt find those on octopart either. I appreciate the calculations you provided too thank you. I figured it was far off but that is staggeringly different.

 

[sfsuphysics]

If someone finds the cost of those higher end caps i can redo the calculations. If future supercaps blast through these numbers that would be awesome, but there is a lot of catching up to do.

No need to redo, just look at the data sheet, 11.1 Wh/kg, you can play happy with the price but as I mentioned earlier "at least an order of magnitude lower than lithium batteries in energy density per mass" cost is certainly a great thing to worry about, but if you can't crack the energy density side of things it really doesn't matter if they were free, no one is going to want either (using the above spreadsheet calcs) 11000+ kg of supercaps to have the same total energy as a Tesla battery, or less than 1/20th the range before you have to recharge. Ok the range part could work if there was an integrated electrical grid so you can constantly (or periodically) recharge like a slot car track, but I don't even want to think about the potential dangers of that. Hell there's a reason why electric buses that pull from overhead wires do so fairly high into the air.