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When the Govt can fix the many pot holes in my area and increasingly on the inside lane of the M25, I will believe they can install and maintain an electric highway....
 

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I completely agree with you but the whole electro-chemistry thing is thinking inside the box from my POV. Every way to make batteries at the moment relies on taking different tacks on the same thing - attach the atoms to some carrier then make more.
I think there could be some way of having one without the other even though that isn't on the spectrum at the moment.
Also I wouldn't say we've had 100 years of quantum leaps. I would say we had a leap at the beginning then 80 years of dragging feet until Lithium came along. I make that two decent overhauls in 100 years. Graphene may lead to another jump but again it's just a new way of making tech that's been around since the 1800 volta.
I haven't read the whole thread yet but 2 things I want to add.

First is that I spoke to an industry insider from a reputable company "off the record" about a year ago and was informed there are test mules running around with LiSulphur batteries with double the energy density and 10C charging rates which charge from 0 to 100% with no tail off. Doubling density at the time means a 200kg 40kWh battery or a 400kg 80kWh battery. Assuming you have a means to dump several hundred kW into the battery that's an 8 minute refill for 220 mile range. No idea on cost though.

Then I was down at Le Mans was a guy who used to work for BMW i came over to chat as he spotted my UK plated rex down there. Very interesting conversation... he left me quizzical as he's now working for a new start up and says he doesn't think batteries are the future of electromobility. I said "not hydrogen" and he said no but couldn't tell me what. So what's that all about? Direct methanol fuel cells? What else can generate 100kW in something car sized? Their goal is "reducing cost to mass market adoption instead of the luxury market".

PS the most range you need at 10C charge rates is about 200 miles. Despite doing a 400 mile trip each way I stopped once on the 180 mile UK side and twice on the 220 mile French side. I took the opportunity to add fuel and battery top up but was actually stopping for coffee, loo and *** break ;) I suppose if you don't smoke(I don't either until I go to Le Mans), have an on board nespresso machine and waste storage tank then longer ranges might be required.
 

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... he doesn't think batteries are the future of electromobility ...
Hmm, hard to see what else is! For my part, I'm now doing about 50% of my recharging from solar, so having spent the capital (6k) I now have 50% free motoring. If I had a home-battery with say 12kWh capacity I'd get this up to 100% free motoring in summer; ok both these figures need a x two-thirds reduction as I do some long-distance petrol journeys, but give me a 300 mile Phev & I'd be closer to 95% free in summer.

An LPG Phev might be cheaper & better, but I still see batteries (or supercaps, whatever) as proven & sorted tech, and one that I can refill at minimal cost. Nothing's going to displace this for me!

It will be some years before anything like the under-motorway inductive charging systems are developed & shown to work, and the static ones use batteries. Or do they think they can make 100% efficient solar cells to put on the roof of a bus & power it with the 30 kW they'd get on a sunny day?

If his energy reserve isn't batteries, then surely it has to be kinetic energy storage, so it's a vacuum-sealed flywheel going at incredibly high rpms using super-strong ultra-high-tensile strength flywheel - maybe layers of graphene - and they'll have to deal with designing & making a suitable containment vessel for it. All that energy's going to be dissipated in a very few milliseconds, if the thing ruptures due to internal fatigue/whatever ... nasty.
 

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I haven't read the whole thread yet but 2 things I want to add.

First is that I spoke to an industry insider from a reputable company "off the record" about a year ago and was informed there are test mules running around with LiSulphur batteries with double the energy density and 10C charging rates which charge from 0 to 100% with no tail off. Doubling density at the time means a 200kg 40kWh battery or a 400kg 80kWh battery. Assuming you have a means to dump several hundred kW into the battery that's an 8 minute refill for 220 mile range. No idea on cost though.
I've been pondering the idea of an electric tank for a long time. Rather than have the atoms attached to whatever goo/metal mix, they should attach to one another or be forced to live inside a box. Only way in/out would be the electrodes and from what I can see (I'm not great on these things but I've done a lot of reading up), the hardest thing would be creating some way of stopping them all trying to get out at once and melting the electrodes/box. At the moment all storage relies on having two sets of chems/metals/whatever basically to keep the peace between + and - until needed. I think there could be legs in + and - being stored seperately in two sides of a "tank" then used/connected on demand.
The current methods are equivalent to storing air in the same tank as petrol then using it all at once.
 

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I've been pondering the idea of an electric tank for a long time. Rather than have the atoms attached to whatever goo/metal mix, they should attach to one another or be forced to live inside a box. Only way in/out would be the electrodes and from what I can see (I'm not great on these things but I've done a lot of reading up), the hardest thing would be creating some way of stopping them all trying to get out at once and melting the electrodes/box. At the moment all storage relies on having two sets of chems/metals/whatever basically to keep the peace between + and - until needed. I think there could be legs in + and - being stored seperately in two sides of a "tank" then used/connected on demand.
The current methods are equivalent to storing air in the same tank as petrol then using it all at once.
If you managed to fill even a small container with electrons, the explosion would make an atomic bomb look minor!

Edit: Actually there is something similar to what you propose, but on a different scale, and that is called a capacitor. In fact to be large enough to get a useful charge you would probably need to rename it as a super-capacitor. Oh...!
 

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I've been pondering the idea of an electric tank for a long time. Rather than have the atoms attached to whatever goo/metal mix, they should attach to one another or be forced to live inside a box. Only way in/out would be the electrodes and from what I can see (I'm not great on these things but I've done a lot of reading up), the hardest thing would be creating some way of stopping them all trying to get out at once and melting the electrodes/box. At the moment all storage relies on having two sets of chems/metals/whatever basically to keep the peace between + and - until needed. I think there could be legs in + and - being stored seperately in two sides of a "tank" then used/connected on demand.
The current methods are equivalent to storing air in the same tank as petrol then using it all at once.
:D

This isn't quite how batteries work.

There's plenty of reading material on chemical batteries you can go look up.

An electrochemical cell is actually quite easy to define - it consists of two electrodes that can be connected either side of an electrical load by conductors such that electrons can flow from one side of the cell to the other, whilst within the cell itself electrons cannot travel, but as it forms part of the electrical circuit then charge carriers must pass the current instead.

This is done in the form of ions in an electrolyte.

A cell can be thought of as a device through which an electric current can pass, but no electrons can pass. It's like an 'electron filter' in an electrical circuit, if you like.

A cell remains electrically neutral at all times. It will polarise but will not change its overall charge state. It does this by changing the oxidation state of the substances in the electrodes, and in doing so valency bonds are made and consumed. This is what prompts the electrons to flow in or out at the electrodes.

As mentioned, an electric 'tank' is a capacitor. But if you do a few sums and work out exactly how much charge you need for a relatively small amount of energy, it is really huge. The physical forces of electrostatic repulsion are huge as you try to cram more and more electrons into a space. This is why batteries are chemical and remain electrically neutral - there is no way they could hold their 'charge' as charged substances. It has to be by a change of oxidation state.
 

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I suspect also that if you tried cramming electrons into your insulated box, you'ld find it very hard to get an insulator good enough to make he box walls from.

Air itself is reckoned to be a pretty good insulator, but breaks down & ionises at about 10,000 volts/cm potential gradient, from memory. Maybe it's 20kV/cm. So somehow you might end up trying to get megavolts in this "box". Lets suppose you do, it's going to be a one-way box - no way will you get the "used" electrons back in the other side! So your car will probably end up with a load of very fine conductive whiskers along the rear bumper, and there will be a gentle charged-wind as electrons still at say 1kV crowd onto the tips of these whiskers, then launch themselves into the air & finally to ground. Just like those piezo-electric pistols you used to be able to buy to eliminate the static build-up on vinyl LPs. Used to have one, lovely toy, sadly can't find it now.

I see no problems with this discharge mechanism, except the largeish current involved may mean rather a large & "interesting" lightning-like effects between the car & the road - or between you & the car behind if it gets too close !!! :):):)

Oh, and the chances are the driver & passengers will end up charged to a kV or two, and their hair will start standing on end - I love it!
 

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As it happens, it might be interesting to consider that the way you put more energy into a capacitor is by increasing the voltage of the charge in the capacitor.

A capacitor in which the electrodes are not connected in some way will always have its rated 'capacitance' of charge on it, but when 'discharged' that charge will be of such small voltage that there is nothing to measure.

For example, let's say you had a 1 Farad capacitor. That is a MIGHTY capacitor. If you put 2 Joules of energy into that capacitor, the voltage of the electrons in it would then be 2V each. It follows this formula;-

E = 1/2 . C . V^2 (a half of the product of capacitance and voltage squared)

OK, so if we put 200 Joules in the electrons would have a voltage of 20V

20,000 Joules, we'd have a voltage of 200V.

20,000 J is 20kW for a second. So that's about cruising power at 70mph for a second.

Let's look at a kWh - 3,600,000J. It'd have to have electrons on it at a voltage of ~3kV.

Here's a 2.3V 1F capacitor;-


Here's a 12V 1F capacitor;-


Do you see how for just 6 times the voltage you get a linear increase of over 10 times, and a volume increase of over 1000 times. That's because of the strong repulsion of charge all together.

If you string capacitors together, their capacitances don't stay the same, unlike battery cells. This is because of the way energy distributes itself in capacitors. If you strung 10 capacitors together for 10 times the voltage, you'd get only 1/10th of the capacitance. So you need 100 of the above capacitor to get 10 times the voltage.

Now multiply that up by 100 times to 3kV. You'd end up with a capacitor some 30 foot long and 10 foot in diameter.

It should go without saying that people don't make high voltage 1F capacitors!

So holding charge directly does not appear to be a viable solution with anything we currently know about capacitors. The River-thing car is about as good as you can currently make capacitors useful in an EV.
 

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Nice one, Donald! Just for interest, I thought I'd design a supercap version of my Ampera battery and see what it looks like. Trawling thru Farnell site looking for the best one to use, I spreadsheeted them and here's the best I can find - it has the best power to weight ratio, as well as lowest total system cost.

There's a nice 3000F 2.7V one for £43.89 in quantity, not surprisingly it's the largest & heaviest in that particular range of caps.

To make a 10 kWh supercap (what the Ampera uses out of it's actual 16 kWh theoretical max) I'll need 3,292 of these.
Together they'll weigh 1,679 Kg and cost me only £144,000 ! The total volume will be 1300 Litres, (each cap being about 0.7 pints in size!) but as that's based on the cylindrical vol, I won't be able to pack them quite that well. Still, a honeycomb pattern should get pretty close, and that volume's only 30% more than my entire boot-space with rear seats folded forwards, so by the time the old battery's gone I should be able to shoehorn them in somehow! If Tesla can do it with small AA cells, why can't I do likewise...superchargers, here I come ...! :)
 

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Nice one, Donald! Just for interest, I thought I'd design a supercap version of my Ampera battery and see what it looks like. Trawling thru Farnell site looking for the best one to use, I spreadsheeted them and here's the best I can find - it has the best power to weight ratio, as well as lowest total system cost.

There's a nice 3000F 2.7V one for £43.89 in quantity, not surprisingly it's the largest & heaviest in that particular range of caps.

To make a 10 kWh supercap (what the Ampera uses out of it's actual 16 kWh theoretical max) I'll need 3,292 of these.
Together they'll weigh 1,679 Kg and cost me only £144,000 ! The total volume will be 1300 Litres, (each cap being about 0.7 pints in size!) but as that's based on the cylindrical vol, I won't be able to pack them quite that well. Still, a honeycomb pattern should get pretty close, and that volume's only 30% more than my entire boot-space with rear seats folded forwards, so by the time the old battery's gone I should be able to shoehorn them in somehow! If Tesla can do it with small AA cells, why can't I do likewise...
On the other hand how large and heavy would the ampera battery be if it was split into 3292 seperate, useable units?
 

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Well, the 2011 Volt's cell is made up of 288 individual cells & weighs 197 Kg, so in theory could be split up rather like the Leaf's can, if you're prepared to ditch the liquid cooling. Looking at the supercaps, there's an improvement in the power/weight ratio as they get bigger, but there's going to be an asymptotic ratio for a particular range/model/type (whatever you want to call it), and even if I could buy a supercap 10x larger than current one I found, it'll probably still weigh 90% of 10 smaller ones stacked up. Put it this way, I can see why EVs aren't yet chock-a-block with them!
 

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There's a nice 3000F 2.7V one for £43.89 in quantity, not surprisingly it's the largest & heaviest in that particular range of caps.

To make a 10 kWh supercap (what the Ampera uses out of it's actual 16 kWh theoretical max) I'll need 3,292 of these.
Nice caps, and nice thought process.

On the other hand how large and heavy would the ampera battery be if it was split into 3292 seperate, useable units?
Well, the problem here is that it'd actually get a lot worse, not better. The reason is that these 2.7V type supercapacitors will go phutt if they hit 3V or so, now imagine stringing 150 of them together. If you throw 400V at that, the chances that every single capacitor will only see less than 2.7V (and therefore survive) is diminishingly small. You have to baby these capacitors so accurately that the add-on kit makes a Li-ion BMS look as complicated as a knife and fork.

That's why you always try to make a single capacitor of the correct operating voltage, not string a series of them together.
 

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Nice caps, and nice thought process.


Well, the problem here is that it'd actually get a lot worse, not better. The reason is that these 2.7V type supercapacitors will go phutt if they hit 3V or so, now imagine stringing 150 of them together. If you throw 400V at that, the chances that every single capacitor will only see less than 2.7V (and therefore survive) is diminishingly small. You have to baby these capacitors so accurately that the add-on kit makes a Li-ion BMS look as complicated as a knife and fork.

That's why you always try to make a single capacitor of the correct operating voltage, not string a series of them together.
Makes sense. So ideally you would have one cap controlled by one BMS (CMS?). Or go for the high tech idea and just use loads with complicated controls?
At the moment that would still be massive and heavy but it would charge much faster than battery tech allows and not have the usual degradation to worry (or not) about.
That brings in another thought. If you have a 100 mile range battery pack, the cooling system, box to put it in, multiple connections for the heavy duty wires between cells, etc - would it be much smaller and lighter than a 50 mile capacitor system? Taking into account the capacitor can make better use of regen and can charge far more quickly, which would people choose?
 

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Why not dramatically lighten existing and future ev's, Czero has very heavy steel doors just like leaf ive lifted them plus boot. It may seem irrational to ask two people to race both 6ft but one weighing 20 st compared to 10st.
 

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Rather then put all these supercaps in series to make a 400V supercap, I'd be tempted to put them in parallel & have a voltage inverter to go from 2.7V up to the 400V the motor wants. But never having designed&built a buck converter to go that way, I have no idea of the currents/cost/chippery etc involved. I'm quite happy going the other way from 40V down to 3.3V - can build those all day long! But it's all hypothetical at the mo.

Re Siraffs qn about 100 mile battery .vs. 30 mile supercaps - I think that's already answered. Ampera 100 mile battery would be about 400 Kg - double the current 45 mile battery weight. Teslas may do better - 85 kWh weighs 540 Kg (but what %age of this do thay actually use?) The Supercaps would be as per my 45 mile Ampera-equiv above - 1700 Kg, then you add the circutry, packaging, and you're looking at 1800 Kg I guess. Too heavy, really. I suspect supercaps only make sense today as a way of quickly storing excess electricity, if your main battery is too small to accept the charging rate that your regen is capable of outputting - which could be rather high if doing an emergency stop! Supercaps are too expensive & heavy at the mo to be used as grunt-work batteries I suspect. But would be fantastic for a car using megawatt chargers & refilling 100s of miles in a minute or so! When they get the weight & cost & size down ... when ...
 
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Why not dramatically lighten existing and future ev's, Czero has very heavy steel doors just like leaf ive lifted them plus boot. It may seem irrational to ask two people to race both 6ft but one weighing 20 st compared to 10st.
Isn't this what the i3 manages to do? loads of carbon fibre, so they have a v large battery but keep the overall weight down.
All vehicle design is a compromise - existing steel-bashing tech for ICEs is well known & understood, and the bent cars easily recycled. As the materials get more sophisticated, stronger & lghter & tougher, they also tend to become harder to repair & recycle, and often use a slower manufacturing process (curing epoxy resins etc), so it's actually rather hard to get the throughput of your new machinery to match a crude but effective steel stamping press + spot-welder robot!
 
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