with respect, this is horse shit. its not an innovation or discovery in cell chemistry. its yet another electrolyte additive that even in the estimation of these lofty articles only stands to slow dendrite growth -- something that does not on the face of it stand to increase energy density. its not something that will move the needle in any way, not now and most likely not ever.
I believe the electrolyte inflammable. If you slow dendrite growth by 1/2 and have an inflammable electrolyte, that's a huge accomplishment. A 10 year battery becomes a 20 year battery and doesn't burn your house down when something goes wrong.
Prediction: If for a given battery, rechargeable or otherwise, Lithium-Ion or otherwise, energy is drained via a pulsed DC (alternating) frequency (think LC coil) rather than direct DC, and if this frequency is switched at regular intervals (let's say at least once a second) -- then the battery should drain slower at a given current level -- than via direct DC (at the same current level) alone...
Reason: Everything in the universe, including metals, including metal oxides, resonate at given (asymmetric, in the case of two or more different substances) frequencies. Electricity is what naturally seeks the balance between those things. But if you disrupt/interrupt the way Nature flows her electricity and keep doing this quickly, over a long period of time, you'll preserve (for a longer period) the asymmetry that allows the electricity to exist in the first place!
I'll bet a 5% longer lifetime out of any battery could be realized -- by "switching it up" -- the frequency (using Pulsed DC) at which the device is drained, that is!
Depending on the application and how far you want to discharge them, Li-ion batteries generally can transfer more charge when drained with DC. Each battery chemistry has different impedance curves.
Higher impedance means more voltage drop will occur across the internal impedance of the cell while trying to pull current. For an equivalent average power, pulses will have to be higher current than a constant DC.
If you pulse the battery, and it is at a low state of charge where the impedance is high, the battery voltage will effectively "droop" and your system may brown out. This means you have to shut down before you've been able to fully discharge.
So pulsed power delivery does not necessarily improve efficiency.
>Depending on the application and how far you want to discharge them, Li-ion batteries generally can transfer more charge when drained with DC
This might very well be true -- but let's hold off on stating things exactly this way, until we've reviewed some fundamentals...
First off, we have a series of different things that "flow" (for lack of a better term) through a wire, when a circuit (in this case, with a battery as the power source) is shorted/closed/"has an electrical load put on it, etc.
First is voltage. Voltage is near-instantaneous. Next is Current. Current is near-instantaneous too -- but it is or should be slower than Voltage. Next is Magnetism, the magnetic field created by the flow of Current. Again, very fast, but should be slower than Current (the Magnetic field is still forming around the conductor in the instant of time that the conductor reaches maximum current -- in fact, it could be argued that Nature is trying to balance the "flow" of Current one way, with the "flow" of a Magnetic field the other...
Next is Heat. Now, heat may not flow at all, if the current carrying capacity of the conductor in question is not overloaded. But if it is, then heat will flow next. Heat is the last fast / most slowest thing that flows down a conductor, if it flows at all.
But the main point is, all of these various different phenomena associated with Electricity -- all flow at different rates of speed (if only by an instant!), that is, one lags behind the other...
Now, the idea that you're going to get more current out of a Li-ion battery when "drained with DC" (Is there any other way to drain it? Pulsed DC is still DC, albeit with a virtual on/off switch that is switched on/off many times per second -- up to millions of times... the cycle time of that being the frequency that I allude to...) is well, dependent on a lot of factors, for example, the battery's impedance, which you allude to next:
>Each battery chemistry has different impedance curves.
Exactly!
But what do you learn in Electrical Engineering 101?
That you the maximum power transfer in a circuit -- when the impedance between the sender and the receiver -- is perfectly matched!
(Because well, otherwise, fundamentally, impedance = "a type of" resistance (if not exactly matched!))
But, there's even more to all of this in batteries!
That's because there is not one circuit in a battery (the circuit between the + and - terminals of the battery!) -- but actually between the interface of the different metals and electrolytes!
That "second circuit" -- is usually not considered as a circuit, because it's sort of hidden, it's sort of not used (and how would you as the user of a battery access it and modify it anyway? It's deeply embedded in the design and construction of the battery! Without the ability to unravel the battery, and sandwich some other material in it, and roll it back up again, it's a circuit that in general, we (the user of the battery!) cannot touch; cannot modify!
In fact, one might go as far as comparing the outside, modifyable circuit between the battery's terminals as the "far field", and the inside, generally speaking non-modifyable circuit (between the battery's different metals eletrolytes) as the "near field":
But you see, it's not just the impedance of the battery!
It's the impedance of the battery's "near field" -- as compared to it's "far field" (the usual circuit between its terminals!)... which brings us to your statement:
>Higher impedance means more voltage drop will occur across the internal impedance of the cell while trying to pull current.
This article doesn't actually get into what the idea is. Instead, it explains the entire history of the world hoping you don't notice the idea is missing
"Although Goodenough will not spell out his precise new idea, he thinks he is on to something."
I got that impression too, but it does say "But the path he has chosen involves one of the toughest problems in battery science, which is how to make an anode out of pure lithium or sodium metal."
I suppose that implies he's trying to make an anode out of pure lithium or sodium, but you never know with science journalism.
My favorite: Chris Moneymaker, the poker champion. However I wonder if there was reverse causation at work: maybe his name and/or his family tradecraft of gold/silversmithing influenced him to try out competitive poker.
There is a thing called "nominative determinism", that says that your name is more likely to match your occupation.
And it looks like a real effect. It is controversial but there are peer reviewed studies that confirm the effect.
There are plenty of theoretical physicists who live to old age. As far as I can see, they all become increasingly irrelevant as they age. Scientific obscurity is all but guaranteed at around 80 years old, despite some people publishing until well after that age.
Does not apply here. Goodenough is not holding back advances under the pretense of "can't be done". In fact, since maybe the time of the Manhattan Project, I'm hard pressed to think of a prominent scientist or physicist who has.
There are many more factors at play here besides density (though that is one of the most important ones if not the most important one). Longevity, cycle time, fast charging, cost and so on are all important factors too.
There are already battery chemistries that are ahead on some of these but afaik there isn't a clear winner yet for a new chemistry, but if it comes I would expect Lithium to be at least one of the ingredients, it is just too tempting a material property wise for this application.
I'd also say the 2 techs that are interesting less for their density aspect and more for longevity are flow batteries and liquid metal batteries. Both would solely be used for grid storage (Flow MIGHT be used for home storage).
Flow batteries are interesting because they have an very long cycle life and their storage capacity is based on how big a holding tank you have (fill the tank, get more storage). They are less interesting because they require mechanical pumps to operate.
Liquid metal batteries are interesting because of their cycle life and they are made out of pretty cheap materials. They are less interesting because they have very high operating temperature requirements.
Amazingly, John B Goodenough is still alive 6 years after this article, and is now 99 years old. "He became the oldest living Nobel Prize laureate on August 27, 2021, upon the death of Edmond H. Fischer." (WP https://en.wikipedia.org/wiki/John_B._Goodenough)
59 comments
[ 2.9 ms ] story [ 128 ms ] threadhttps://www.metaltechnews.com/story/2020/09/23/tech-metals/g...
https://insideevs.com/news/436729/sk-innovation-develop-batt...
Goodenough was awarded a Nobel, and the technology is being commercialized.
I believe the electrolyte inflammable. If you slow dendrite growth by 1/2 and have an inflammable electrolyte, that's a huge accomplishment. A 10 year battery becomes a 20 year battery and doesn't burn your house down when something goes wrong.
Prediction: If for a given battery, rechargeable or otherwise, Lithium-Ion or otherwise, energy is drained via a pulsed DC (alternating) frequency (think LC coil) rather than direct DC, and if this frequency is switched at regular intervals (let's say at least once a second) -- then the battery should drain slower at a given current level -- than via direct DC (at the same current level) alone...
Reason: Everything in the universe, including metals, including metal oxides, resonate at given (asymmetric, in the case of two or more different substances) frequencies. Electricity is what naturally seeks the balance between those things. But if you disrupt/interrupt the way Nature flows her electricity and keep doing this quickly, over a long period of time, you'll preserve (for a longer period) the asymmetry that allows the electricity to exist in the first place!
I'll bet a 5% longer lifetime out of any battery could be realized -- by "switching it up" -- the frequency (using Pulsed DC) at which the device is drained, that is!
See the plot in the 2nd to last page of this PDF: https://www.omicron-lab.com/fileadmin/assets/Bode_100/Applic...
Higher impedance means more voltage drop will occur across the internal impedance of the cell while trying to pull current. For an equivalent average power, pulses will have to be higher current than a constant DC.
If you pulse the battery, and it is at a low state of charge where the impedance is high, the battery voltage will effectively "droop" and your system may brown out. This means you have to shut down before you've been able to fully discharge.
So pulsed power delivery does not necessarily improve efficiency.
This might very well be true -- but let's hold off on stating things exactly this way, until we've reviewed some fundamentals...
First off, we have a series of different things that "flow" (for lack of a better term) through a wire, when a circuit (in this case, with a battery as the power source) is shorted/closed/"has an electrical load put on it, etc.
First is voltage. Voltage is near-instantaneous. Next is Current. Current is near-instantaneous too -- but it is or should be slower than Voltage. Next is Magnetism, the magnetic field created by the flow of Current. Again, very fast, but should be slower than Current (the Magnetic field is still forming around the conductor in the instant of time that the conductor reaches maximum current -- in fact, it could be argued that Nature is trying to balance the "flow" of Current one way, with the "flow" of a Magnetic field the other...
Next is Heat. Now, heat may not flow at all, if the current carrying capacity of the conductor in question is not overloaded. But if it is, then heat will flow next. Heat is the last fast / most slowest thing that flows down a conductor, if it flows at all.
But the main point is, all of these various different phenomena associated with Electricity -- all flow at different rates of speed (if only by an instant!), that is, one lags behind the other...
Now, the idea that you're going to get more current out of a Li-ion battery when "drained with DC" (Is there any other way to drain it? Pulsed DC is still DC, albeit with a virtual on/off switch that is switched on/off many times per second -- up to millions of times... the cycle time of that being the frequency that I allude to...) is well, dependent on a lot of factors, for example, the battery's impedance, which you allude to next:
>Each battery chemistry has different impedance curves.
Exactly!
But what do you learn in Electrical Engineering 101?
That you the maximum power transfer in a circuit -- when the impedance between the sender and the receiver -- is perfectly matched!
(Because well, otherwise, fundamentally, impedance = "a type of" resistance (if not exactly matched!))
But, there's even more to all of this in batteries!
That's because there is not one circuit in a battery (the circuit between the + and - terminals of the battery!) -- but actually between the interface of the different metals and electrolytes!
That "second circuit" -- is usually not considered as a circuit, because it's sort of hidden, it's sort of not used (and how would you as the user of a battery access it and modify it anyway? It's deeply embedded in the design and construction of the battery! Without the ability to unravel the battery, and sandwich some other material in it, and roll it back up again, it's a circuit that in general, we (the user of the battery!) cannot touch; cannot modify!
In fact, one might go as far as comparing the outside, modifyable circuit between the battery's terminals as the "far field", and the inside, generally speaking non-modifyable circuit (between the battery's different metals eletrolytes) as the "near field":
https://en.wikipedia.org/wiki/Near_and_far_field
But you see, it's not just the impedance of the battery!
It's the impedance of the battery's "near field" -- as compared to it's "far field" (the usual circuit between its terminals!)... which brings us to your statement:
>Higher impedance means more voltage drop will occur across the internal impedance of the cell while trying to pull current.
Absolutely correct!
But let's add an extra statement t...
"Although Goodenough will not spell out his precise new idea, he thinks he is on to something."
I suppose that implies he's trying to make an anode out of pure lithium or sodium, but you never know with science journalism.
Oh, and he did win the Nobel Prize in Chemistry in 2019[1].
[0] https://thedriven.io/2020/04/06/li-ion-co-inventor-patents-g... [1] https://en.m.wikipedia.org/wiki/John_B._Goodenough
No idea if that was their original birth surname, but I wouldn't be surprised.
Too on the nose for a serious novel.
Followup from 2017: "Has lithium-battery genius John Goodenough done it again? Colleagues are skeptical" https://qz.com/929794/has-lithium-battery-genius-john-gooden..., https://news.ycombinator.com/item?id=13916255 (154 comments)
Another story about the same guy: https://news.ycombinator.com/item?id=14058696 (2017, 140 comments)
Imagine if Einstein, Hawking, Feynman, etc all lived to be 100.
It is quite a sad future that awaits.
https://en.m.wikipedia.org/wiki/Leonard_Susskind
People can remain inspirational and contribute well into old age
https://en.m.wikipedia.org/wiki/Freeman_Dyson
https://www.goodreads.com/quotes/111818-science-advances-one...
We don’t need for it to be true, we simply need to be open to learning and accepting new ideas at any age.
Believing Max Planck’s Principle to be a certainty is an example of his principle in action.
Too early to tell really.
> Believing Max Planck’s Principle to be a certainty is an example of his principle in action.
I haven't said that.
Are we going to see a decent factor density improvement over Lithium ion anytime soon?
There are already battery chemistries that are ahead on some of these but afaik there isn't a clear winner yet for a new chemistry, but if it comes I would expect Lithium to be at least one of the ingredients, it is just too tempting a material property wise for this application.
- Recently LiFePO4 achieved energy densities on par with alternatives while retaining its long cycle life.
- Sodium-ion is gaining momentum, but it's not meant to be particularly energy-dense - just cheaper and longer living.
All this is working to reduce the cost per kWh - which will likely remain stable for the next few years because of high demand.
Meanwhile solid state electrolyte batteries are still a long way from commercialization.
I'd also say the 2 techs that are interesting less for their density aspect and more for longevity are flow batteries and liquid metal batteries. Both would solely be used for grid storage (Flow MIGHT be used for home storage).
Flow batteries are interesting because they have an very long cycle life and their storage capacity is based on how big a holding tank you have (fill the tank, get more storage). They are less interesting because they require mechanical pumps to operate.
Liquid metal batteries are interesting because of their cycle life and they are made out of pretty cheap materials. They are less interesting because they have very high operating temperature requirements.
https://cleantechnica.com/files/2020/02/bloomberg-nef-batter...
I think we seem to think here that things can improve indefinitely but some constants come from physics.
https://www.briangwilliams.us/economic-growth-2/images/900_4...
I thought that electrons shuttle from the anode to the cathode.