elma wrote:So far you're making a convincing argument which I don't disagree with. The environmental problems which concern me are more to do with the batteries. I've seen how they extract and refine lithium and it's not good. I also am aware there is an environmental cost to disposing of old batteries but have no idea how recyclable or damaging they are.
I'm actually pro electric cars but have always believed that battery technology, currently, is their Achilles heel. Are you well informed on this as well Simon? It's something I'll be researching in time but haven't had a chance yet.
I agree that batteries have always been the Achilles heel of electric cars, and probably what has stopped adoption until now. Electric motor technology (including the inverter/controller) suitable for high performance electric cars has been ready for at least 20 years but the battery tech hasn't. The issues being of course high weight, low energy density, and slow charging.
Modern lithium iron batteries don't completely solve these problems but with a bit of innovate design get you "close enough" to bridge the gap to practicality. Tesla in particular pioneered two "breakthroughs" in applying batteries to electric cars - the shape and location of the battery and the temperature regulation.
The first generations of electric cars (even including the Tesla roadster) and electric hybrids put the batteries in more traditional locations such as under the bonnet next to the motor, and where the fuel tank would go in a normal car, taking up some of the boot space etc. As they're so big and heavy they take up a lot of space that could be luggage space and being up high they raise the centre of gravity a lot.
Tesla's insight was to make the entire floor the full width of the car and right from axle to axle one big massive flat battery pack that is bolted up onto the body from underneath. It's about 4 inches thick so it does lower the ground clearance a bit but it completely frees up the boot for luggage, the front "engine bay" to be another boot (huge in the RWD model, reduced in size but still present in the 4WD version) and the rear for an engine. To make the battery safe in that location it is made of modules which are separately contained and literally "fire-walled" from each other and the interior of the car. If one module somehow caught fire it would vent towards the ground and other nearby modules are unaffected. This grid like structure is reinforced and a significant part of the weight of the battery pack, however it becomes a major structural part of the car in both frontal and side impacts. Because this battery pack (which is about 500Kg) is literally under the floor it gives the car an unusually low centre of gravity - helped by the alloy body construction.
The other breakthrough they made is their active cooling/heating system for the battery - lithium batteries are most "happy" over a relatively narrow range of temperatures. To get long life, high efficiency, high power output and fast charging you have to be able to both heat and cool the batteries to keep them in their happy range. To do this they have a pumped cooling system which I believe actually uses traditional glycol coolant similar to a normal engine - this is pumped around past all the cells in the battery pack through a heat conductive sleeving that is in contact with the individual cells. There are quick release coolant lines connecting all the battery modules to each other and to the rest of the car, so when the entire battery pack is dropped out you have both electrical cables and some coolant lines that are disconnected.
Here is what one looks like:
https://teslamotorsclub.com/tmc/threads ... ack.34934/
There are three separate cooling loops in the car which connect batteries, a small radiator, the motor and the inverter, which can be reconfigured and connected to each other with valves depending on what needs heating or cooling.
On a very cold morning it would initially use some energy from the batteries to heat the fluid to warm the batteries up - sounds wasteful but you gain more than you lose by bringing the batteries up to a comfortable working temperature. Later on as the engine and inverter module start to heat up their waste heat can be pumped to the batteries to keep the batteries warm (in cold conditions) for "free" using the waste heat from those. If you're in a hot climate the motor, inverter and batteries may all need cooling instead in which case a small radiator cools all three of them, and also provides A/C in the car I believe.
In recent software updates the heating/cooling system will even come on automatically when the car is parked and locked to either actively cool or warm the batteries if the temperatures are getting dangerously low or high. I don't recall what the exact figures are but its something like above 40 degrees and below -10. This uses a small amount of energy but the payoff is a massively increased battery life, because subjecting the batteries to temperature extremes shortens their life even when not in use. When the car is driving I think it tries to keep the batteries in a narrower range between about 20-30 degrees.
Some (most ?) other makes of EV do NOT do all this elaborate battery temperature management, and subsequently don't have anything like the same battery life expectancy.
The point of all this is that if your batteries can last twice as long then you both halve the recycling problem and also avoid the depreciation cliff that you might get if the battery was expected to die after 10 years...Nobody is going to buy a 10 year old EV if you can expect a £15000 battery to be about to die but if you can reasonably expect 20 years (eg the life of the car) out of the battery then it won't be an issue.
As for recycling of lithium - it doesn't look like there is much recycling specifically for lithium at the moment as it is not "valuable" enough. However it is also only a very small part of the materials in a lithium battery:
https://waste-management-world.com/a/1- ... -challenge
It's certainly something that needs to be thought through. The fact that Tesla is building a battery factory that will have more output of lithium batteries than the entire rest of the world current production is quite sobering, but I would imagine that regulations will come into place that make it illegal to dump or crush electric cars without first removing the battery for reuse or recycling of some kind.
white exec wrote:Some really good arguments by Simon. Allowing millions of people to inefficiently burn unnecessarily transported liquid fuel has had its day. We now know how to do better, and will one day soon look back on all this with some disbelief!
Some things are best done 'centrally', and that certainly includes use of energy. From the 1960s, and almost all of Moscow was kept heated by piped hot water from just four "thermal stations". In the mid-70s when we visited, one of these was burning wood and general rubbish, the others fossil fuels. All probably Gazprom now, I guess! Only snag was it was decreed in the Moscow diary the day that winter would start, and this was writ in stone, so if it got cold a week early, it could be a bit grim. How cold? -32C over Christmas/New Year.
Heh heh...
If you're generating electricity from fossil fuels centrally, it can certainly be done more efficiently, for example another point I thought of is even if a fossil fuel generator only has a 50% efficiency for rotational output driving a generator the waste heat can also be harvested to run something like a thermopile to generate secondary electricity - when you don't have size, weight, complexity or (to some degree) cost constraints that you have in a car there is a lot more you can do. On a car apart from using a small amount of the waste heat for heating the interior the rest is all thrown away - and I can't think of anything that could be added to a car to harness that waste heat in the way that you could do at a power generation plant.
The great thing about electricity though is that some methods of generation are more efficient when done centrally at scale, but there is absolutely nothing to stop you doing your own local generation with solar panels either. Electricity becomes the global energy currency if everything can run off it.
Will we still be allowed to 'motor' as we do today ? Will we be issued with 'transport credits' which permit us to travel x miles in our own vehicle, and once they're used up, we've got to buy more on the 'transport credits trading scheme' (government controlled, of course !). In 20+ years time, how far are we intending or needing to travel in cars ? 
I'm not sure if that's a good thing, or a bad thing though 
