Battery breakthroughs

That would suit my application perfectly. I only go through around 15 charge cylces per year and the weight saving would be awesome. I wonder if they require similar levels of cooling to existing EV batteries. I then wonder whether the weight of the cooling system would eat into the weight savings.

 

Solid state batteries won't have dendritic growth. And, they will have higher energy density, and better thermal characteristics. They will be essentially non-flammable.

Has John B. Goodenough been mentioned in this thread? There are other people also working on solid state batteries.

 

Not impressed with Sion Power cycle life. Only the lower energy version has about 350 cycles and the high energy version about 130. I don't think this will be acceptable for most people. Image from SionPower.com

 

That certainly isn't going to cut it for commercially produced electric cars. The industry standard is 80% capacity retained after 2000 cycles. No doubt there will be some niche applications where cycle life isn't as important.

But I note the graphs are dated over a year ago. Is it possible they have significantly improved lifespan since then?

 

Possible, yes, likely no. They are acutely aware that cycle life is the Achilles heel of LiS batteries and if there was any improvement in the last year they would have updated their web site. I have read about Sion and LiS batteries for at least 10 years now and the other main problem is that the high energy density is possible because there are several chemical changes, not just one as in normal batteries. Each of these changes is at a different voltage, so it does not stay flat for long but slopes down, this during each charge/discharge cycle. Not as bad as capacitors but you have to design the system to work well at the lower end of the voltage. Too many trade-offs for me. Improving cycle life has been their goal for more than 10 years.

 

There is no particular problem in designing switch-mode electronics to work efficiently over a wide range of voltages. I notice, for instance, that the LED light bulbs I buy will work happily at anywhere between 100 and 250 volts - AC or DC! It is probably cheaper to provide a 'universal voltage' bulb than designing them for different voltages around the world. You run into problems with some batteries in which internal resistance increases as they discharge which means you can't get the extra current you need to maintain power levels but I don't imagine th

at is a problem with these ones.

Cycle life seems to be their worst feature, although as pointed out earlier this becomes less of a problem if the improved energy density can reduce the number of cycles needed to give it them a reasonable life.

 

I don't much like the idea of many kilograms of Lithium metal being present. What happens in a crash?

 

May not be too bad. Lithium's not as dramatic as sodium or potassium. With water, it reacts to produce hydrogen and LiOH I expect, but from what I can recall it doesn't get hot enough to ignite the hydrogen and go bang!

They'll have to do the necessary testing I suppose.

 

Pure lithium metal burns very hot, and the fire is very hard to extinguish. Hot li-ion electrolyte leaking or exploding from an overheating cell is pretty flammable, too. That's why shipping lithium batteries in bulk has been banned from air freight, and it's why the U.S. Postal Service does not accept lithium batteries for shipping. Airline attendants receive special training in dealing with lithium battery fires, in case of a laptop or cellphone bursting into flame.

But lithium-ion batteries, despite the name, don't actually contain that much lithium. As I recall, it's only 1-2% by weight. If a lithium-air fuel cell (often wrongly called a "battery") contains as much lithium as the name suggests, then it's hard to see how that won't be an extreme fire hazard.
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I'm no defender of batteries, as you know. But I'm not sure what would cause it to go on fire anyway. Lithium is stable enough in air, and even if some enthusiastic firefighter elects to souse them in water, the reaction is relatively gentle. Hydrogen is produced, but I think that is so light it would dissipate quite quickly outside, and not pose much of a hazard.

I suppose short circuits might cause the things to overheat and ignite.

Personally, I feel that lithium batteries are potentially quite dangerous. I keep a very firm grip of the ones in our house in phones, cameras, drills etc. etc. and never leave them unattended when being charged. It is my belief that relying on things that need external electronics to prevent them going up in flames is already a step too far.

 

Are you just pulling our legs here, Martin? Playing dumb? Once again, it's hard to believe someone who calls himself a "scientist" can really be so ill-informed.

What happens when you put lithium in water?

Lithium reacts intensely with water, forming lithium hydroxide and highly flammable hydrogen. The colourless solution is highly alkalic. The exothermal reactions lasts longer than the reaction of sodium and water, which is directly below lithium in the periodic chart.
​

The danger of fire in a battery-electric vehicle has certainly been exaggerated in the popular press. Statistics show that a car fire is something like3 to 5 times more likely to happen in a gasmobile.

However, one thing that I find very promising about the demo that Ionic Materials did of their solid-state polymer ("plastic") li-ion battery is that it's actually fire retardant!

I am very much looking forward to seeing solid-state li-ion batteries entering commercial production, and I'm eager to see just what advances will come from that. I hope for faster charging and more cycle life, in addition to eliminating the danger of fire. I also hope that, if the same manufacturing processes used to make consumer electronics can be used to make solid-state li-ion batteries, that the price will drop rapidly over just a few years.

Perhaps I'm being overly optimistic, but hey, I'd rather be hopeful even if I'm occasionally disappointed, than to believe in a bleak and hopeless future!

Up the EV revolution!

 

I wasn't playing dumb. I may BE dumb, but I hope not in the case under discussion. One of us certainly was, it seems. You may be disappointed to find that not everything on the internet is true, and in this case you seem to have stumbled onto the site of a complete numpty who is as ignorant of simple chemistry as a sparrow.

That wasn't Lithium in the video you showed. It was sodium. You can tell in two ways

1. The lithium-water reaction is much gentler, and ignition doesn't take place as it does with the other alkali metals.
2. The flame was orange-yellow - characteristic of sodium. Lithium burns with a scarlet flame

You can find plenty of further good information on the net, in a few seconds, such as this for instance:

http://www.bbc.co.uk/schools/gcsebitesize/science/add_ocr_pre_2011/periodic_table/group1rev3.shtml

Lithium fizzes fairly vigorously and gives off hydrogen and slowly gets smaller until it vanishes but it doesn't get hot enough to autoignite. Sodium shoots about the surface of the water and the reaction is exothermic enough to ignite the hydrogen and you get an orange flame. Potassium is even more dramatic. It autoignites immediately giving a bright lilac flame followed by an explosion! The Lithium - water reaction lasts longer than the others BECAUSE it is gentler! You may also be interested to learn that LiOH is a much less 'strongly alkaline' base than NaOH or KOH. which also conflicts with what you imply in your post.

The danger in lithium batteries is that a short circuit or overcharging can cause them to heat up to the point where they go on fire. I understand that the electrolyte is also inflammable, and once the casing of the cell bursts open you have a vigorous fire on your hands. It is not easy to put out by water, and squirting water over it will generate hydrogen as well as failing to cool down the reacting lithium.

Batteries are a huge pain in the backside. I hate the idea of building into systems, components which have limited life, are expensive, costly, often dangerous, bulky, and have to be worried about and looked after and replaced. Life without them would certainly not be bleak! Why not be really optimistic, and look forward to something better such as Fuel cell or capacitor powered cars.

However, it is also worth remembering that there are no guarantees that the universe is constructed in such a way that we can have exactly what we want. It may NEVER be possible to construct a battery with the energy density of a simple tank of diesel.

 

I thank you for the correction and the information, Martin.

It's too bad that someone who appears to be so well-informed in matters of chemistry, remains a science denier on the subjects of the thermodynamics of hydrogen-powered fuel cell cars, and a science denier on the (lack of) potential for compressed hydrogen being a practical fuel for wheeled vehicles.

That is nearly all true. Water can be used to temporarily cool a li-ion fire, altho it takes a lot of water in relation to the amount of lithium present. I find it interesting that airline attendants are taught to treat small li-ion battery fires (in laptops and cell phones, for example) by first pouring two bottles of water on the fire, to cool down the burning device, and then using a non-water-based fire extinguisher to keep it from re-igniting.

I agree; kinda like using a Model T Ford for transportation. Things will get easier over time for batteries and BEVs, just as they did for gasoline-powered motorcars. Batteries keep improving every year. The element hydrogen... not so much!

But still, BEVs are already much, much more practical than trying to use highly compressed hydrogen as a fuel.

I doubt we ever will get batteries or capacitors with the energy density of gasoline or diesel. Theoretically that's possible, but I suspect practical limitations will prevent it. And so what? Claiming batteries need to have an ED that high is only an EV-hater's argument. It has no logical value, nor any reasoning behind it. Batteries are only one part of an EV powertrain, just as the gas tank is only one part of a gasmobile's powertrain.

Furthermore, a BEV's powertrain does not need to match the overall energy density of a gasmobile's powertrain to make gasmobiles obsolete. Almost nobody is going care if a BEV's curb weight is a few hundred pounds more than a comparable gasmobile, once BEVs are better than gasmobiles in nearly all other respects.

All this has been pointed out to you before. You keep demonstrating that you're a hardcore science denier.
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Battery cars are not 'science'. They are a flop.

After years of advertising hoopla, grants to develop them and to buy them, they make up a tiny percentage of cars sold. I don't know how much more evidence you need to be convinced that the car-buying public is simply not interested in fiddling about with the wretched things.

If you look at the monthly sales figures for the wide range of plug-ins now available, you find that significant growth is limited to a small clutch of them. The remainder of models available show little growth, no growth, or falling growth!

I doubt if you know enough science to identify a science 'denier' if one came up and bit you on the buttocks. Anyone incapable of identifying what is clearly sodium hitting water and accepting that it is lithium is about as clueless as it's possible to get.

Pointing out that battery cars are a flop is not 'denying science'. It is pointing to a glaringly obvious fact. They have had several years trying to persuade the public to change and have achieved little more than one or two percent of the market. This despite generous grants, subsidies and other incentives, growth has been almost identical to the deployment of new models. In other words, little or no average growth.

Your enthusiasm for battery cars is similar to that of your enthusiasm for the estor scam, and I suspect just as ill-advised although it may take a bit longer for the brown stuff to enter the rotating blades. I vaguely remember you as one of the lunatic fringe of fanatics there. One wonders what the next bandwagon you will jump on will be. Spider-silk space elevators perhaps? Or cold fusion? Whatever it is you will, no doubt, be telling us how much we will regret not investing in it it! Just before it all collapses in ruin.

 

I have no particular pretensions to chemical knowledge, having never studied it after school, by the way. But I think one has to have walked about in some form of a daze not to know that the characteristic colour of sodium plasma is orange. Surely you have seen the orange low-pressure sodium lamps used in street lighting around the world? Or been sufficiently curious about how the colours of fireworks are defined?

Had my career taken another course and I'd ended up as a jazz pianist (another enthusiasm of mine) I would have had to wear a blindfold and earplugs all my life in order NOT to have learned that orange = sodium!

 

*Face Palm*

 

Tesla is already more successful than Lexus ever was and Lexus was the last challenge to the upper crust luxury segment.
Nothing is making upper crusters prefer Tesla BEVs over everything else by a huge margin except the raw and radical superiority of the technology. This just the way it is and the difference will only get greater not less and it will repeat in all segments. Its like Musk says, the products stand on their on merits not on fluff or puff pieces.