Capacitors

[DonkeyApple]

Capacitors aren't exactly ideal for powering EVs but what is the reason that we haven't considered using them to bridge charging times?

On paper your EV could have a capacitor and a battery to allow you to stop, bang in a slug of electricity to a capacitor quicker than filling a petrol tank and then drive off with the capacitor discharging into the battery to recharge it as you carry along.

Is it cost, packaging or physics that makes this implausible?

[DonkeyApple]

Dave Hedgehog said:

https://www.youtube.com/watch?v=KQ2Eo6wl5r0

Thanks. This is a solution which is being considered for other battery tech, such as solid state so as to limit the restrictions caused by their initial very high costs while taking advantage of the complimentary way they will work with old battery tech.

[DonkeyApple]

saaby93 said:

Rather than capacitors what about some form of pumped storage system like the CEGB uses.
You have one tank on the roof and one in the floor
When you charge the car or use regen it pumps water into the roof tank.
When you need more power you flush the top tank through a generator
or better still use it to drive a water wheel connected directly to the transmission

Or a horse, on a treadmill on the roof? For people without an Esso fuel depot in their drawing room, powering an EV by green apples would be ideal?

[DonkeyApple]

TheDeuce said:

Thanks for the responses regards power density guys. I already pretty much knew the answer... There's a reason there is billions being invested in new cell tech as opposed to super capacitors.

This goes way beyond EV too. Every aspect of modern tech is crying out for better energy storage. I type this as my phone has just bleeped to ask me for more charge... We need better batteries. Clever stop gap solutions might help a little here and there, but nothing will be as impactful as the next generation of cells will be.

Sadly, we can have no idea if that technology will arrive tomorrow, next year, or in twenty years time. All we can know for certain is the that current EV's will feel like dinosaurs when eventually the new breed comes along and weighs less than ICE and goes twice as far. In the mean time, at least we can say that current li-ion is getting the job done well enough. Driving an EV today isn't a struggle - even if we can imagine it being improved in the future. The same way we all lived very happily with tapes ahead of CD's

Given the typical length of investment cycles being around ten years, the typical length of time for bringing an extraction plant on stream (up to 15 years from start of finance raising to profitability) the amount of money going in does tend to make it clear that no significant change is anticipated for very many years. Since the late 90s, retail gamblers have been hurling their savings at any penny share entity working on graphene. As of yet to no avail and pretty much to the point that we now just walk out of the meeting if it transpires that someone's been silly enough to entertain a discussion on it. It'll happen at some point but it's for dumb money to bankroll, smart money is going to the dumb tech that actually works now.

It would be a genuine 'black swan' event that delivered a commercially viable, mass produced new solution that was smaller, lighter and released the biggest shackles to mankind in the 21st century.

If we just spend a moment considering the existing tech that would be manifestly changed in its use and capabilities of it were possible to store power efficiently then you begin to see that such a breakthrough will change the world more than the internet did or smart phones. It is a truly momentous event in waiting from micro tech to massive industrial solutions. 1859 was when Gaston Plante invented the rechargeable battery and in 160 years it is just about the only technology that genuinely hasn't moved forward in a major step change. In 2021 we are still utilising the same rules of chemistry to produce an extremely large, heavy and low energy density battery. Only hype and spin prevents the clarity of seeing the absence of significant change.

100 years on from really, really crappy petrol out competing batteries as a means to power a car and in 2021, petrol remains superior as a mechanism for storing energy for a car. The absolutely farcical complexity of getting petrol from several miles below the Earth's crust into a car still cannot be bettered by a battery despite the magnitudes of superiority the electric motor has over the comically complex and inefficient internal combustion engine.

However, like you point out with our smart phones, the battery isn't very good at all but we have all adapted around that fallibility to the point that it's genuinely a non issue. We charge our phones at night, we top them up when out and about without giving it a second thought. Those of us who have lifestyles that keep us away from USB sockets for long periods of time have adapted and found other solutions to charging.

The same is true with batteries in cars. They might be crap but the reality is that they are already good enough to work. There are very few people in the U.K. who couldn't make an EV work if they had no choice. The vast majority of humans wake up each day and simply do exactly the same as they did the day before. They've even made films about the repetitive mundanity of almost all human life. At the same time all these humans adapt instantly and almost without any thought to changes and evolutions in how their environment works.

The reality is already clear, has been for a few years and is exactly as predicted: in the main, excluding the apex shoppers who have to have whatever is new in order to find any happiness and confidence in life, people will simply switch to EVs based on the price being at their spending level and refuelling being easy and cheap. All we are seeing today is the start of the millions of households who know they never need to go a long distance with a particular car and are also unlikely to ever need to refuel away from home. We've had a few years of obsession over the hypermiling, 1980s travelling salesman that really just hasn't existed for years. There aren't millions of blokes ploughing hundreds of miles a day in a Vectra or Mondeo any more. All those blokes are now retired and just driving to garden centres, country pubs and doing tens of identical local journeys. And those who still have no choice but to travel long distances will be among the last to switch in 15-20 years time if their employers don't create private networks for them which many are to facilitate staff movement between regional business units and many business are to facilitate customer and partner EV needs.

While these tens of millions of suburban runabouts are slowly switching to EV as more and more EVs hit consumer budgets all these private remote charging networks that they don't really need will be growing, Li tech getting marginally better and maybe new Li tech such as solid state coming on stream. The more easily scared humans will become less terrified as the change becomes more boring and less new. Some of the most rabid antis will have their statistically inevitable conversion to being rabid enthusiasts full of hate for what they once were. People will naturally come to terms with the reality and mundanity of their day to day existence. They'll still post all their fabricated billionaire, action hero tripe on social media, still rush to tell anyone who'll listen just how dynamic and awesome they are as a human but they will have long since accepted that the reality is that they drive to the exact same place on the exact same day, at the exact same time and do the exact same thing and that their EV works perfectly as a result.

There will be no issue with the Grid because the Grid will price consumers away from the peak hours and consumers will follow the pricing without a second thought.

There will be no issue with fast charging because pricing will deter those who really have no need of it.

Grazing will become as common place as Nectar points. People will plug in everywhere they stop to claim their reward for being special and important.

The same people will be sitting by the same roads waiting for someone to arrive with some fuel for them.

Employers and landlords will add endless numbers of chargers to facilitate business and to avoid tax penalties. Employers will also evolve their roles so that they work within the remit of EVs. Their staff will have to drive EVs so the employer will have to ensure work charging so as to not legally discriminate against their poorer employees and they will have to use more local labour to avoid the uncompetitiveness of sending a work unit on a 400 mile journey that would involve hours of zero productivity. No employer wants to be paying a worker to be sitting in a car doing no work if they can avoid it anyway. It's exactly why the number of those jobs has fallen off a cliff in recent years.

For many people on this planet, switching to EV is an impossible dream without a step change in pricing and technology. For a small island like Britain that is one of the wealthiest places on Earth and where workers, employers and lifestyles can easily adapt almost without sentient thought, it is a piece of piss that the vast majority of people could do today if the initial purchase price were down to their desired level, which will eventually happen even with Li batteries.

My pondering around capacitors was whether they could become one of the transition bridges over the next 20 years until Li battery tech is replaced to facilitate a 'splash and dash' fudge solution where a user can dump 50-100 miles into a car very quickly and drive off with the capacitor then releasing that energy into the Li pack which the motor draws from. Such a solution would come close to doing away with the hybrid phase that awkwardly sits between pure ICE and pure EV.

[DonkeyApple]

saaby93 said:

TheDeuce said:

We need better batteries.

Other things too.
Hydrogen cars that use a piston engine are coming through- but how to store the hydrogen?
How does the weight of a hydrogen tank compare to that of batteries? Or can a softer tank be used?
Fuel cells might be able to use capacitors instead of batteries for load levelling.
Some EVs are more efficient in miles per kwh than others - size, weight and aero.

They're already here. The fuel for them doesn't exist and there is no commercially viable position for them, or a legal one for that matter, within the U.K.

[DonkeyApple]

Frimley111R said:

Based on the LPG ones, they are predictably heavier than a fuel tank but much much lighter than batteries. There is a min spec for the strength of hydrogen tanks I am sure but it's not the tech that is the issue, its consumers. Charge an EV at home by plugging it in or go to a service station and connect up a hydrogen line to your car? And there wil be all the 'what if it blows up' comments that will put people off.

Absolutely no company is going to build a retail distribution network for a handful of people who cannot afford an EV. That cost alone guarantees no customers. But as the fuel is made from EV fuel it will always be much more expensive, this such consumers could never afford it. And if the Grid apparently doesn't have enough electricity to fuel EVs then it very obviously doesn't have enough to create hydrogen. And that's just for hydrogen electrolysis EVs. There is already legislation to stop hydrogen ICE due to its NOx pollution and it would be even more expensive as it is considerably less efficient. Nor will such price sensitive consumers like paying for a fuel that escapes so freely having paid so much money for it.

In the U.K. if green hydrogen is proven to be possible it will be used as a battery to store renewable energy and as a means to dilute natural gas and reduce emissions in the home and energy industry.

But all the global projects to create green hydrogen, if it works, are only set to double the amount of global hydrogen production by 2030 which means there still wouldn't be enough to power any kind of automotive fleet. By the time the capability exists to produce that amount of hydrogen the idea of developed nations ever using it in cars will have long been forgotten and everyone will be in cars with electric motors and quite happy.