Otherwise known as explosives, rocket fuel, and most kinds of batteries.
Authorities said they used 32,000 gallons of water to extinguish the flames because the vehicle's batteries kept reigniting. At one point, Herman said, deputies had to call Tesla to ask them how to put out the fire in the battery.
Where I used to work, they had a machine shop that used to work with magnesium, before my time. Firefighters had a rule if they got a call: don't go in.
Another place I used to hang around during college was a robotics research lab. They had a bunch of 1st or 2nd gen l Li-Poly batteries, in pouch form, to run their little robots. I was told to never use a any of the fire extinguishers hanging on the wall if there was a battery fire. I don
They exist. They trade safety for energy-to-weight and energy-to-volume density.
People act like it's evil bogeyman keeping the masses from using electric cars. It's not. It's technology limitations, some of them surmountable given enough money today, but some of them because of hard physics-based theoretical limits.
Having to carry your own oxidizer as opposed to sucking it out of the air is one of those physics-based limits. A system that carries its own oxidizer will always weigh more than one that only ne
Again: li-ion batteries do not contain oxidizers. The energy storage mechanism is not a fuel-oxidizer reaction. That would be a fuel cell, not a battery. The energy storage mechanism is the voltage potential difference between a lithium ion intercalated into graphite vs. a lithium ion intercalated into a mixed metal oxide.
Fire in a li-ion battery depends on the type. In any system where energy is stored, there is the potential for creating heat. In a battery, this can be from short-circuiting the anode a
From freshmen chemistry I seem to recall that oxidation/reduction reactions are a generic term for two species exchanging electrons along a potential difference. Actual oxygen need not be involved in the oxidizer.
The "packed closely together" bit is the problem. Fuel and air don't spontaneously combust because while there's a lot of both, the contact surface area is relatively small and confined to the surface of the liquid fuel. Hence a gasoline spill can burn but won't explode. Diesel I don't belive will
From freshmen chemistry I seem to recall that oxidation/reduction reactions are a generic term for two species exchanging electrons along a potential difference.
You stated that li-ion batteries contain "oxidizers". Name the component that you think is an "oxidizer". Do you think graphite is an oxidizer? Do you think mixed metal oxides are oxidizers? Do you think hydrocarbon carbonates are oxidizers?
There are no oxidizers in li-ion batteries.
. Fuel and air don't spontaneously combust because while there's a lot of both, the contact surface area is relatively small and confined to the surface of the liquid fuel. Hence a gasoline spill can burn but won't explode.
The rate of ICE vehicle fires vs. EV fires tells a different story, re: ICE safety vs. EV safety.
Who'd have imagined that a system where fuel is just contained loose in a big tank (vs. the huge number of safeties in EV battery packs, to first prevent, and then isolate, failures) - fuels chosen to burn hot and with lots of energy, is plumbed up to a hot engine with tons of moving parts, sparked, burned, and then exhausted passing through a catalytic converter hot enough to ignite grass - might start fires at pretty regular intervals?
I think the oxides are a product of an oxidation reaction that occurs when the battery cycles between charged and discharged states. The metal ions pick up or lose electrons moving from anode to cathode and back. One of those is an oxidation reaction. Hint: it's the one where the oxide reforms.
I think the oxides are a product of an oxidation reaction that occurs when the battery cycles between charged and discharged states.
You think wrong. They are formed at the factory and remain in their form (apart from any slow degradation processes over the battery's lifespan).
Li-ion batteries work by intercalation. Please look up that word before trying to continue this conversation, because I don't want to spend my whole evening dealing with the basics here.
Every single battery ever works by having one type of molecule/atom/ion give up an electron and another type of molecule/atom/ion picking up an electron.
Oxidation is defined as losing an electron. Whatever picks up that electron, either the anode or whatever is on the cathode via the electric circuit is known as the oxidizer of the ion/atom/molecule that originally gave up that electron.
Further, let's see what wiki says about Lithium Ion batteries in particular. Oh look:
The reactants in the electrochemical reactions in a lithium-ion cell are materials of anode and cathode, both of which are compounds containing lithium atoms. During discharge, an oxidation half-reaction at the anode produces positively charged lithium ions and negatively charged electrons...
"Fuel and oxidizer packed close together... otherwise known as explosives, rocket fuel, and most kinds of batteries."
What SPECIFICALLY are you definining as an "oxidizer" in a battery that "explodes" in reaction with "fuel"? Name the component. Are you calling mixed-metal oxides (aka, rocks) "oxidizers"? Are you calling graphite "oxidizers"? This is a very simple question here. What is it that you think is so eager to burn when it comes into contact with "fuels"
FYI, intercalation reactions happen every single day all around you, in that's how clays in the soil store nutrient cations in their interlayer space. Every day they're gaining and losing cations, due to weather, the action of plants, etc. How eager are you to call soil clays "oxidizers"? Are you afraid of having soil clays near fuel because they might behave like "rocket fuel and explosives?
And also FYI, there is a class of next-gen electrodes known as "conversion cathodes" (like iron fluoride) and "conve
Holy crap dude. It doesn't matter if the bond structure doesn't change. If a lithium ion loses an electron, whatever picks it up is by definition the oxidizer.
In a lithium battery, that's (by definition) the graphite at the anode and the other lithium ion at the cathode.
If the energy gradient is there, the reaction will occur spontaneously. An example of spontaneous reactions in nature is rusting: oxidation by atmospheric oxygen.
In solid rocket fuels and many explosives, there is a potential barrier that ne
Okay, after calling you out repeatedly for refusing to answer this very simple question:
What SPECIFICALLY are you defining as an "oxidizer" [aiche.org] in a battery that "explodes" in reaction with "fuel"? Name the component.... What is it that you think is so eager to burn when it comes into contact with "fuels"?... I'll loop back: name the specific battery component that you're calling "an oxidizer" that is "packed close together with fuel" in a manner akin to "rocket fuel and explosives".
The anode and the cathode packed closely together that will undergo a thermal runaway, chemically and thermodynamically, if not mechanically, akin to an explosion of a fuel-air mixture.
Fucking hell you are obtuse.
I answered your question three times. I (and other posters) explained to you several times why it's called an oxidation reaction even if no oxygen is involved and no molecular bonds change. You just got it in your head that some RightwingNutjob used a fancy scientific word wrong and no amount of po
And you're STILL refusing to answer what you're calling an oxidizer that you think is akin to "rocket fuel and explosives". Name the component, for god's sake. Are you calling both mixed metal oxides and graphite both "oxidizers"? And no, touching the anode and cathode together in a fully discharged battery will not cause any sort of reaction, they're not even remotely hypergolic with each other, they're inert; and the only "reaction" from contacting them in a charged cell is heat given off from a short
If you touch the cathode and anode together in a *charged* battery, by say poking a nail through it or squishing it with a hammer, then what happens, smart-ass?
And everyone keeps telling you that if an atom or ion gives up an electron, that's oxidation and whatever took that electron is the oxidizer. And if that electron being givne ip results in a lower energy state, then rhe reaction is exothermic and is subject to thermal runaway. Thermal runaway in a fuel air mixture is an explosion. In a controlled sce
The confounding between oxidation/ reduction and the half-reaction at an electrode against an electrolyte has been confusing teenage proto-chemists since before anyone in this conversation was born. At the molecular level they are the same thing, but when engineered into different assemblies, they become very different things.
But the stored energy remains dangerous. We've all made bangs and flashes from stored energy. Did you see the Formula-1 on Sunday, and
And you're STILL refusing to answer what you're calling an oxidizer that you think is akin to "rocket fuel and explosives". Name the component, for god's sake. Are you calling both mixed metal oxides and graphite both "oxidizers"? And no, touching the anode and cathode together in a fully discharged battery will not cause any sort of reaction, they're not even remotely hypergolic with each other, they're inert; and the only "reaction" from contacting them in a charged cell is heat given off from a short cir
The confounding between oxidation/ reduction and the half-reaction at an electrode against an electrolyte
What you're calling "the half-reaction at an electrode against an electrolyte" is the migration of intercalated Li+ to free Li+ in the electrolyte, reducing the screening charge in the electrode, causing electrons to leave. No change in oxidation states. Still Li+. Still sp2-bonded carbon in the anode and the cathode remains in its layered, spinel or polyanion form with no changes to its oxidation stat
You are talking to someone who would prepare aluminium filings as an energy booster for his home-made explosives.
I couldn't get the grain size small enough to have a noticeable effect, at least when experimenting in a town. I didn't have somewhere far enough away from being overheard to try with larger charges.
There are loads of webpages you can find that describe the Li-ion half reaction that is oxidation at the anode:
LiC6 --> Li+ + C6 + e-
That's an oxidation reaction. No oxygens are involved (not a fuel cell), but it's oxidation nonetheless.
More fundamentally, if the battery provides current, where do the electrons that make up that current come from? They come from the anode. Where does the anode get free electrons? From the oxidation reaction.
The Li in "LiC6" is not bonded to the graphite, but rather exists in the van der Waals gap between graphite layers as a Li+ guest ion. Consequently, there exists an extra electron to balance out the Li+. The reaction is of the form x A+ + x e- + [Z] Ax+[Z](sup)x-, and is known as an electron/ion transfer reaction, not a redox reaction. [Z] becomes a macroanion with mobile negative screening charges, akin to a capacitor. A redox reaction by contrast requires a change in the oxidation states of the reactant
If there was no oxidizer the battery would not work. Somewhere in the chemistry something is giving up an electron. Something else is absorbing that electron. The giver of the electron is being oxidized (even if oxygen is not involved) and the absorber is being reduced.
If the lithium is giving up the electron, then what compound is getting it? There is the oxidizer. Yes, the oxidizer gets reduced in the course of the chemical reaction.
If there was no oxidizer the battery would not work. Somewhere in the chemistry something is giving up an electron.
Lithium is an ion on both sides. It is intercalated on either end. As a lithium ion moves from the cathode to the anode during charging, the cathode loses a +1 (as the intercalated lithium leaves) and the anode gains a +1 (as new lithium intercalates). This creates a voltage differential. There is no change to the bonding structure of either the cathode or anode.
Some mixed metal oxides are rocks, but I wouldn't call LiCoO2 a rock. It's a metal oxide whose Co changes oxidation state from +4 to +3 during discharge, ie is reduced. It's the oxidizer because it takes that electron during discharge. I'm not sure why it's anathema call a solid object (or even a rock for that matter) an oxidizer.
Secondly, LiCoO2 is not used in EV batteries. The closest would be NCA or NMC, which are predominantly oxides of nickel (today cobalt is less than 10% of the metal content).
Third, mixed metal oxides are very much "rocks", and are indeed ores (though sulfates like pentlandite are more commonly used in battery nickel production - cobalt is often found in a solid-state solution in pentlandite). The only reason lithium is not commonly found in nickel/cobalt ores is that the processes that concentra
Seen on a button at an SF Convention:
Veteran of the Bermuda Triangle Expeditionary Force. 1990-1951.
Fuel and oxidizer packed close together (Score:5, Interesting)
Otherwise known as explosives, rocket fuel, and most kinds of batteries.
Authorities said they used 32,000 gallons of water to extinguish the flames because the vehicle's batteries kept reigniting. At one point, Herman said, deputies had to call Tesla to ask them how to put out the fire in the battery.
Where I used to work, they had a machine shop that used to work with magnesium, before my time. Firefighters had a rule if they got a call: don't go in.
Another place I used to hang around during college was a robotics research lab. They had a bunch of 1st or 2nd gen l
Li-Poly batteries, in pouch form, to run their little robots. I was told to never use a any of the fire extinguishers hanging on the wall if there was a battery fire. I don
Re: (Score:3)
Maybe that'll be Musk's next great invention. Self-extinguishing batteries.
Re: Fuel and oxidizer packed close together (Score:5, Informative)
They exist. They trade safety for energy-to-weight and energy-to-volume density.
People act like it's evil bogeyman keeping the masses from using electric cars. It's not. It's technology limitations, some of them surmountable given enough money today, but some of them because of hard physics-based theoretical limits.
Having to carry your own oxidizer as opposed to sucking it out of the air is one of those physics-based limits. A system that carries its own oxidizer will always weigh more than one that only ne
Re: (Score:4, Informative)
Again: li-ion batteries do not contain oxidizers. The energy storage mechanism is not a fuel-oxidizer reaction. That would be a fuel cell, not a battery. The energy storage mechanism is the voltage potential difference between a lithium ion intercalated into graphite vs. a lithium ion intercalated into a mixed metal oxide.
Fire in a li-ion battery depends on the type. In any system where energy is stored, there is the potential for creating heat. In a battery, this can be from short-circuiting the anode a
Re: Fuel and oxidizer packed close together (Score:1)
From freshmen chemistry I seem to recall that oxidation/reduction reactions are a generic term for two species exchanging electrons along a potential difference. Actual oxygen need not be involved in the oxidizer.
The "packed closely together" bit is the problem. Fuel and air don't spontaneously combust because while there's a lot of both, the contact surface area is relatively small and confined to the surface of the liquid fuel. Hence a gasoline spill can burn but won't explode. Diesel I don't belive will
Re: Fuel and oxidizer packed close together (Score:3)
You stated that li-ion batteries contain "oxidizers". Name the component that you think is an "oxidizer". Do you think graphite is an oxidizer? Do you think mixed metal oxides are oxidizers? Do you think hydrocarbon carbonates are oxidizers?
There are no oxidizers in li-ion batteries.
The rate of ICE vehicle fires vs. EV fires tells a different story, re: ICE safety vs. EV safety.
Who'd have imagined that a system where fuel is just contained loose in a big tank (vs. the huge number of safeties in EV battery packs, to first prevent, and then isolate, failures) - fuels chosen to burn hot and with lots of energy, is plumbed up to a hot engine with tons of moving parts, sparked, burned, and then exhausted passing through a catalytic converter hot enough to ignite grass - might start fires at pretty regular intervals?
Re: Fuel and oxidizer packed close together (Score:1)
? Do you think mixed metal oxides are oxidizers?
Really?
I think the oxides are a product of an oxidation reaction that occurs when the battery cycles between charged and discharged states. The metal ions pick up or lose electrons moving from anode to cathode and back. One of those is an oxidation reaction. Hint: it's the one where the oxide reforms.
Re: (Score:2)
You think wrong. They are formed at the factory and remain in their form (apart from any slow degradation processes over the battery's lifespan).
Li-ion batteries work by intercalation. Please look up that word before trying to continue this conversation, because I don't want to spend my whole evening dealing with the basics here.
Re: Fuel and oxidizer packed close together (Score:2)
Every single battery ever works by having one type of molecule/atom/ion give up an electron and another type of molecule/atom/ion picking up an electron.
Oxidation is defined as losing an electron. Whatever picks up that electron, either the anode or whatever is on the cathode via the electric circuit is known as the oxidizer of the ion/atom/molecule that originally gave up that electron.
https://en.m.wikipedia.org/wik... [wikipedia.org]
Further, let's see what wiki says about Lithium Ion batteries in particular. Oh look:
The reactants in the electrochemical reactions in a lithium-ion cell are materials of anode and cathode, both of which are compounds containing lithium atoms. During discharge, an oxidation half-reaction at the anode produces positively charged lithium ions and negatively charged electrons...
htt [wikipedia.org]
Re: (Score:2)
Let's go back to your original comments:
"Fuel and oxidizer packed close together ... otherwise known as explosives, rocket fuel, and most kinds of batteries."
What SPECIFICALLY are you definining as an "oxidizer" in a battery that "explodes" in reaction with "fuel"? Name the component. Are you calling mixed-metal oxides (aka, rocks) "oxidizers"? Are you calling graphite "oxidizers"? This is a very simple question here. What is it that you think is so eager to burn when it comes into contact with "fuels"
Re: (Score:2)
FYI, intercalation reactions happen every single day all around you, in that's how clays in the soil store nutrient cations in their interlayer space. Every day they're gaining and losing cations, due to weather, the action of plants, etc. How eager are you to call soil clays "oxidizers"? Are you afraid of having soil clays near fuel because they might behave like "rocket fuel and explosives?
And also FYI, there is a class of next-gen electrodes known as "conversion cathodes" (like iron fluoride) and "conve
Re: Fuel and oxidizer packed close together (Score:2)
Holy crap dude. It doesn't matter if the bond structure doesn't change. If a lithium ion loses an electron, whatever picks it up is by definition the oxidizer.
In a lithium battery, that's (by definition) the graphite at the anode and the other lithium ion at the cathode.
If the energy gradient is there, the reaction will occur spontaneously. An example of spontaneous reactions in nature is rusting: oxidation by atmospheric oxygen.
In solid rocket fuels and many explosives, there is a potential barrier that ne
Re: (Score:2)
Okay, after calling you out repeatedly for refusing to answer this very simple question:
What SPECIFICALLY are you defining as an "oxidizer" [aiche.org] in a battery that "explodes" in reaction with "fuel"? Name the component. ... What is it that you think is so eager to burn when it comes into contact with "fuels"? ... I'll loop back: name the specific battery component that you're calling "an oxidizer" that is "packed close together with fuel" in a manner akin to "rocket fuel and explosives".
and you STILL refusing to
Re: Fuel and oxidizer packed close together (Score:2)
The anode and the cathode packed closely together that will undergo a thermal runaway, chemically and thermodynamically, if not mechanically, akin to an explosion of a fuel-air mixture.
Fucking hell you are obtuse.
I answered your question three times. I (and other posters) explained to you several times why it's called an oxidation reaction even if no oxygen is involved and no molecular bonds change. You just got it in your head that some RightwingNutjob used a fancy scientific word wrong and no amount of po
Re: (Score:2)
And you're STILL refusing to answer what you're calling an oxidizer that you think is akin to "rocket fuel and explosives". Name the component, for god's sake. Are you calling both mixed metal oxides and graphite both "oxidizers"? And no, touching the anode and cathode together in a fully discharged battery will not cause any sort of reaction, they're not even remotely hypergolic with each other, they're inert; and the only "reaction" from contacting them in a charged cell is heat given off from a short
Re: Fuel and oxidizer packed close together (Score:2)
If you touch the cathode and anode together in a *charged* battery, by say poking a nail through it or squishing it with a hammer, then what happens, smart-ass?
And everyone keeps telling you that if an atom or ion gives up an electron, that's oxidation and whatever took that electron is the oxidizer. And if that electron being givne ip results in a lower energy state, then rhe reaction is exothermic and is subject to thermal runaway. Thermal runaway in a fuel air mixture is an explosion. In a controlled sce
Re: (Score:2)
The confounding between oxidation/ reduction and the half-reaction at an electrode against an electrolyte has been confusing teenage proto-chemists since before anyone in this conversation was born. At the molecular level they are the same thing, but when engineered into different assemblies, they become very different things.
But the stored energy remains dangerous. We've all made bangs and flashes from stored energy. Did you see the Formula-1 on Sunday, and
Re: (Score:2)
And you're STILL refusing to answer what you're calling an oxidizer that you think is akin to "rocket fuel and explosives". Name the component, for god's sake. Are you calling both mixed metal oxides and graphite both "oxidizers"? And no, touching the anode and cathode together in a fully discharged battery will not cause any sort of reaction, they're not even remotely hypergolic with each other, they're inert; and the only "reaction" from contacting them in a charged cell is heat given off from a short cir
Re: (Score:2)
What you're calling "the half-reaction at an electrode against an electrolyte" is the migration of intercalated Li+ to free Li+ in the electrolyte, reducing the screening charge in the electrode, causing electrons to leave. No change in oxidation states. Still Li+. Still sp2-bonded carbon in the anode and the cathode remains in its layered, spinel or polyanion form with no changes to its oxidation stat
Re: (Score:2)
You are talking to someone who would prepare aluminium filings as an energy booster for his home-made explosives.
I couldn't get the grain size small enough to have a noticeable effect, at least when experimenting in a town. I didn't have somewhere far enough away from being overheard to try with larger charges.
Re: Fuel and oxidizer packed close together (Score:3)
There are loads of webpages you can find that describe the Li-ion half reaction that is oxidation at the anode:
LiC6 --> Li+ + C6 + e-
That's an oxidation reaction. No oxygens are involved (not a fuel cell), but it's oxidation nonetheless.
More fundamentally, if the battery provides current, where do the electrons that make up that current come from? They come from the anode. Where does the anode get free electrons? From the oxidation reaction.
Re: (Score:2)
The Li in "LiC6" is not bonded to the graphite, but rather exists in the van der Waals gap between graphite layers as a Li+ guest ion. Consequently, there exists an extra electron to balance out the Li+. The reaction is of the form x A+ + x e- + [Z] Ax+[Z](sup)x-, and is known as an electron/ion transfer reaction, not a redox reaction. [Z] becomes a macroanion with mobile negative screening charges, akin to a capacitor. A redox reaction by contrast requires a change in the oxidation states of the reactant
Re: (Score:2)
If there was no oxidizer the battery would not work. Somewhere in the chemistry something is giving up an electron. Something else is absorbing that electron. The giver of the electron is being oxidized (even if oxygen is not involved) and the absorber is being reduced.
If the lithium is giving up the electron, then what compound is getting it? There is the oxidizer. Yes, the oxidizer gets reduced in the course of the chemical reaction.
Re: (Score:2)
Lithium is an ion on both sides. It is intercalated on either end. As a lithium ion moves from the cathode to the anode during charging, the cathode loses a +1 (as the intercalated lithium leaves) and the anode gains a +1 (as new lithium intercalates). This creates a voltage differential. There is no change to the bonding structure of either the cathode or anode.
And again, we come back to: do
Re: Fuel and oxidizer packed close together (Score:2)
Some mixed metal oxides are rocks, but I wouldn't call LiCoO2 a rock. It's a metal oxide whose Co changes oxidation state from +4 to +3 during discharge, ie is reduced. It's the oxidizer because it takes that electron during discharge. I'm not sure why it's anathema call a solid object (or even a rock for that matter) an oxidizer.
Re: (Score:2)
First, link [slashdot.org]
Secondly, LiCoO2 is not used in EV batteries. The closest would be NCA or NMC, which are predominantly oxides of nickel (today cobalt is less than 10% of the metal content).
Third, mixed metal oxides are very much "rocks", and are indeed ores (though sulfates like pentlandite are more commonly used in battery nickel production - cobalt is often found in a solid-state solution in pentlandite). The only reason lithium is not commonly found in nickel/cobalt ores is that the processes that concentra