The Dark Side Of Tesla's Masterful Short Squeeze [View article]
For anyone who doesn't want to read this, feel free to skip by it...
Julian—
Thanks for taking the tim to reply over the holiday weekend. I have no reason other than to help present the balanced view.
“It seems to me you are championing the use of prismatic LiFePO4 and trying to dismiss alternatives…”
I have never championed LiFePO4 in any of its forms. I have worked with it from time to time, but it didn’t work for the applications we were interested in. In fact, full EV applications are one where I don’t feel that iron phosphate can truly excel. I also have never said that they are safer. In fact, I often say the opposite. I don’t know about the BYD E6, but I know that the Volt uses manganese-based chemistry (I believe spinel). The fire source was tracked to a coolant leak on to electronic components, as opposed to a cell-related problem, which could happen to any system using coolant. A similar cause was noted for the FIsker, although the storm surge from Hurricane Sandy which completely submerged the cars could have also been the cause.
“If you put a lot of energy together in a small space…”
No argument here. There benefits and drawbacks to both the large and small cell approach. For many designs, I prefer the small cell approach, for others large cells. Of course, that can be dictated by the customers. The Tesla’s design mitigates safety problems to a huge extent, but by no means completely eliminates it. No battery design completely eliminates it.
“By all means use LiFePO4 prismatics - 20Ah cell no problem, but don't go around selling the idea that this a license to skip battery design safety protocols…”
Since I don’t work with iron phosphate, I have no desire to put them into packs. And I have always made the point that NO Li-ion battery chemistry is completely safe. Some are safer than others, but they all will catch fire just the same. I have seen safety testing done by OEMs in several different fields where iron phosphate cells burned the same as “unsafe” LiCoO2 cells. Safety is always my first concern at the cells level, unless dictated otherwise, although most of those features fall on the MEs and EEs. The best anyone can do is design to the spec supplied by the customer, add a huge safety margin, and add to that safety trying to anticipate what people might do. That being said, it is impossible to design for every ridiculous scenario that the end user might conceive. You can only mitigate the damage that they will do to the pack and themselves. And I won’t be the least bit offended if you don’t want to do anything that involve cells I have worked on, although there are probably a couple of industries where the odds are ~50:50 that you will have to use them…
“As a matter of fact the tests performed are closer to the charge/discharge limits set by the Model S battery management system in standard mode …”
I don’t know what you consider deep discharge, but the some of the same cells Tesla uses are spec’d to ~300 cycles before reaching 80% capacity under deep discharge (full 100% state of charge to 0% state of charge). Of course, Panasonic could be lying about the data that they supply, but then again, I have run the same testing in the lab and gotten similar results. I don’t think that you misrepresented the data as much as misinterpreted it as to how it applies to automotive. If that degree of capacity restriction, i.e. only using ~40% of the battery, is how they are guaranteeing the Model S battery life, then everyone is really only getting ~34kWh battery. That is the difference between “true” and “usable” capacity/energy. Thermal pack management is done by a number of manufacturers. We have supplied prototypes for a variety of uses that have charge/discharge restriction tied to temperature, at both the high and low end.
My point has consistently been that lab testing is no substitution for real world usage. Tesla has used a lot of pack building and cycling techniques that other manufacturers have used successfully over the past 2 decades to improve safety, extend cycle life, and optimize performance. That being said, lab testing just adds another data point to help improve your case. The jury will be out until a significant number of vehicles are in use for a significant number of miles to be statistically relevant. I am not trying to cast any FUD, just show the real world challenges of pack design for an uncertain usage model, how there is a disconnect between test data and real usage, and the difference between the PR hype and the real world.
“That brings us to the next point. 45,000 miles / 3 years of use…”
There is no guarantee that the pack will have 91% energy left. Some may have 95%, others 80%. That is going to be highly dependent on usage. And I did mean “buy.” Sometimes my hands can’t keep up with my brain. I never suggested that they should pay recycling fees for the pack. My point (again pretty consistently) has been, if there are huge breakthroughs in performance or cost, why would anyone buy a used pack, when a new pack, with better performance could be had at a small premium. Unless they plan on taking a loss on any used packs. If I was a stock holder in Solar City, or a customer, I would be very skittish at the prospect of using a pack of unknown veracity for any purpose.
You quoted Spiderman, so allow me to quote Pulp Fiction. “If my answers frighten you then you should cease asking scary questions.”
The Dark Side Of Tesla's Masterful Short Squeeze [View article]
Julian—
First let me thank you for not referencing the same tired out Panasonic presentation that everyone spouts off about. Second, I had seen that ECS abstract.
That being said, yes, I will argue such a simple thing, especially when you misrepresent/misinterpret data.
Your link is not the cell spec. It is an abstract for an ECS presentation, which might be the same general chemistry, but is not the same cell (especially since it says 400mAh cells). Those cycles are nowhere in the vicinity of deep discharge. An end of charge voltage of 4.05V corresponds to ~85% state of charge (SOC), while an end of discharge voltage of 3.6V corresponds to ~40% SOC. So in the end they are cycling over ~40% of the available capacity of the cells. Not very impressive in that light. Additionally, as I have noted time and time again, simple charge discharge cycles are not very indicative of how a cell will behave in an EV-type application, which requires higher rate pulses in both the charge and discharge regime often with no equilibrating rest in between. So what you really have is a battery that is probably double in size to ensure that it will still have a lot of range in 5+ years time.
I could care less how it works. The question is WILL it work, and the jury is out as to whether or not used packs of unknown veracity will be good for anything other than a several hundred kg doorstop. That doesn’t even begin to get into, this question:
If the price of batteries drops, or the performance see the order of magnitude increases that everyone screams about, why would anyone by a used battery when a newer, better performing battery can be had for a small premium?
And I didn’t twist what you said. “High residual value of battery makes cheap upgrade path for new tech - i.e. a new battery sale for every model s owner every few years for a few thousand USD.” To me, that says that people are going to be clamoring for a new battery after a couple of years, which they very well might. They are highly unlikely to pay $3500 for it though, since the battery now is probably >$10k in cell costs alone, likely higher.
The Dark Side Of Tesla's Masterful Short Squeeze [View article]
Julian—
Access to pilot scale equipment (~200k cells/year) would give them access to equipment and that’s it. Then there is the fun bit of having to source all the actual components, which is virtually impossible in some instances unless you have a well defined spec in mind already or an in with the company in question. It would give them in house capability to license and test things from a variety of places, most of which are dead ends. The national labs are particularly harsh about who gets credit for discoveries and are loathe to give up credit or rights to patents.
As for licensing it back, the Japanese are loathe to bring in anything out of house unless it was developed nearby, i.e. in Japan.
I believe John’s comment was that he had heard that Tesla is considering manufacturing the cells themselves, not doing R&D./pilot scale.
While I agree about the research culture in Asia, to a point, the same holds true to many universities and national labs, unfortunately. Many “breakthroughs” in academic settings are virtually meaningless in the real world for the same reasons that you stated about battery research in Asia.
The Dark Side Of Tesla's Masterful Short Squeeze [View article]
" Model S NCA battery is good for nearly 800,000 miles."
There is no evidence of this in real world use or empirically.
There is currently no residual value is used batteries. Lots of people hope that there will be, but there just isn't. Besides, what value is there in a battery that has an unknown heritage in terms of usage other than the number of miles?
As an aside, if the Model S needs a battery upgrade every few years, there will be a lot of pissed off people. Of course, since most of Tesla's battery warranties are of the, "Does not cover normal capacity loss," variety, it wouldn't surprise me one way or another if they need to be replaced.
The Dark Side Of Tesla's Masterful Short Squeeze [View article]
"The Model S is 'mostly' American made, whether you believe it or not."
Unless Panasonic has a 18650 manufacturing facility stateside that no one knows about, I don't know if it is even "mostly." The parts may all be put together here, but they definitely come from all over.
Tesla's Q1 Earnings, An Epic April Fools Prank [View article]
John--
I found an error in my calculation. Going from the Panasonic spec sheet, if they are using the highest capacity cell, it is closer to 250Wh/kg. If they are using one of the lower capacity cells, it is in the 225 to 235 Wh/kg range.
The really curious thing is that recently the capacities for the two highest capacity cells has be reduced by about 50mAh each from where they were initially presented at.
Tesla's Q1 Earnings, An Epic April Fools Prank [View article]
Dave_M—
At least you and I are in agreement that there is potential for failure in anything.
--Acceptable range—Why does the range have to be >200 miles for it to be successful? All that I ever hear is how most everyone drives <40 miles in a day. It can’t be both ways, i.e. needing to have >200 miles and only needing 80 to 100. -Weight—Tesla’s pack is so large, they go from ~270Wh/kg at the cell level to ~150Wh/kg at the pack level. This means that there is significant weight added to the pack to make it functional. This is an inherent weakness with the small cell approach. -Cost—Again, I have never seen hard cost numbers from anyone about ANY OEM’s pack costs, just lots of fuzzy numbers and cell cost numbers. -Thermal management--This is one area that I think Tesla excels at. That being said, with a different cell choice, they could have lessened the need for this type of management. -Operational life—TBD. There is not enough statistical evidence to support this.
I don’t know if Tesla has the best battery solution. That remains to be played out. I disagree about unacceptable range, I agree about cost, although that stems significantly from battery costs, and I think even Tesla is TBD for thermal management and operational life. I suspect that Tesla is not nearly as ahead of everyone as you think, but that’s only because I have spoken with enough people at different levels of the battery supply chain to know what some people have in the wings.
Tesla's Q1 Earnings, An Epic April Fools Prank [View article]
KCN--
"For 30M miles - resolve your skepticism by calling Tesla."
That really isn't the independent verification that I mean, but thanks anyway.
As for Li-ion in a pure EV, I have read a couple of reports from either OEMs and/or the govt about EVs from the 1990s that were highly successful in small fleet testing, but were not pursued because there was no market or economic incentive. I can't speak for Daimler, but I know that Toyota has a very good handle on EV technologies. They don't have any reason to get in the game until costs are to their liking for components, particularly batteries.
My cost comment wasn't directed at you, but since you felt the need to stick in your $0.02... Cost always matters. If better, cheaper batteries are developed, what incentive does anyone have to use old batteries in the mythical "second life" that people so desperately want to believe in? How can Tesla guarantee residual value for something that may be completely obsolete? I have had enough "behind the doors" discussions with people all up and down the supply chain from raw material vendors all the way up to OEMs in a number of industries, and what is said then is not lock step in line with what the PR hacks spout off about.
As for Vegas, I get into the action for the hell of it, but I usually stick to cards, although it is fun to gawk at the suckers.
Tesla's Q1 Earnings, An Epic April Fools Prank [View article]
Dave_M--
"Not in automotive. None of the other EVs on the road use the affordable 18650 cells."
Not actually. A number of OEMs have looked at it, but there is a weight penalty using a small cell approach, which they are loathe to take. Same goes with liquid cooling. Additionally, with liquic cooling there is another major failure mode that has to be taken into account. In reality, you could probably make a care with similar range and cheaper. Heck, I even think Tesla could do the same if they made the right cell choice.
Tesla's Q1 Earnings, An Epic April Fools Prank [View article]
KCN--
I had heard that there may be 30 million aggregate miles. I don't know if that is fact or not since I only have the CTO's word to go on. "Battery incident" could mean anything from simple cell failure or a bad weld to complete catastrophic fire, depending on the source. I am assuming that he means complete catastrophic fire.
As for high power, even Tesla is no where near the realm of high power, even in EV applications. A fast 0 to 60 time does not necessarily mean high power.
Dave_M--
I know what he meant, and he was still wrong. People have been making large arrays of 18650s into larger packs going on 20 years. People have been using active liquid cooling with Li-ion for nearly as long. Their approach is not unique, and is not necessarily lower cost.
Tesla's Q1 Earnings, An Epic April Fools Prank [View article]
KCN--
"FYI. TSLA invented the battery pack - that now has over 30 Million miles without any incidence - and the electric drive train."
I have never read such a bogus statement before. Tesla invented neither the battery pack (none of which have 30 million miles on them) or the electric drive train. They have taken a number of techniques/technologies that others have developed and incorporated them into their packs/drive train.
"TSLA battery pack proves that Li-Ion can be effectively used in high power applications including Boeing 787 if properly designed."
Pure EV applications are one of the milder applications that Li-ion can be used for. It is nowhere in the realm of high power. It might be high power compared to laptops or cell phones, but is nothing close to most applications. People have been doing high power Li-ion for nearly 2 decades now, and Tesla isn't even in the ballpark.
"My bad. Yuasa exonerated. Note to self to inform Boeing of good news."
That battery has been in the works for years and just shows that lab testing is no substitution for real world usage. There are only two or three actual usage models where lab testing give a >90% view of what should happen under actual usage. Everything else gets you into the ballpark at best.
Why Batteries Are Too Valuable To Waste On Solar Power Integration And Electric Cars [View article]
Dave_M--
Much less has changed in the automotive industry than you would think over the past few years. Many of the same issues that were being looked at the last time EVs were made commercially have cropped up in one form or another this next go around. the different is that the OEMs have a somewhat better understanding this time around. That being said, what is said behind closed doors and what is said in public are two completely different things.
Toyota spends plenty on R&D and they have a very good understanding of the Li-ion space (at least in my dealings with them). I would like to think that they have a pretty good nose for good tech. I wonder why the RAV4 EV would cost so much. It couldn't be because of the batteries could it?
Why Batteries Are Too Valuable To Waste On Solar Power Integration And Electric Cars [View article]
Not this tired presentation again...
There is no 1C charging in there. It is all at at rates much lower than 1C. The "1C" discharge is also not really 1C. If you look at the two main graphs depicting cycle life, they have very different voltage windows, 4.2 to 2.5 at RT, and then 4.1 to 2.5 at elevated temperatures. Lowering the cutoff voltage can give the illusion of more capacity just as lowering the charge voltage at higher temperature cycling can improve the cycle life.
Fact of the matter is that single cell test data is meaningless as to how a pack will perform, for any application. This is particularly true when comparing simple charge discharge cycles with complicated usage profiles that can be seen with many systems. Until a statistically significant amount of people have a large number of miles, the data is nice, but proves nothing.
The Dark Side Of Tesla's Masterful Short Squeeze [View article]
Julian—
Thanks for taking the tim to reply over the holiday weekend. I have no reason other than to help present the balanced view.
“It seems to me you are championing the use of prismatic LiFePO4 and trying to dismiss alternatives…”
I have never championed LiFePO4 in any of its forms. I have worked with it from time to time, but it didn’t work for the applications we were interested in. In fact, full EV applications are one where I don’t feel that iron phosphate can truly excel. I also have never said that they are safer. In fact, I often say the opposite. I don’t know about the BYD E6, but I know that the Volt uses manganese-based chemistry (I believe spinel). The fire source was tracked to a coolant leak on to electronic components, as opposed to a cell-related problem, which could happen to any system using coolant. A similar cause was noted for the FIsker, although the storm surge from Hurricane Sandy which completely submerged the cars could have also been the cause.
“If you put a lot of energy together in a small space…”
No argument here. There benefits and drawbacks to both the large and small cell approach. For many designs, I prefer the small cell approach, for others large cells. Of course, that can be dictated by the customers. The Tesla’s design mitigates safety problems to a huge extent, but by no means completely eliminates it. No battery design completely eliminates it.
“By all means use LiFePO4 prismatics - 20Ah cell no problem, but don't go around selling the idea that this a license to skip battery design safety protocols…”
Since I don’t work with iron phosphate, I have no desire to put them into packs. And I have always made the point that NO Li-ion battery chemistry is completely safe. Some are safer than others, but they all will catch fire just the same. I have seen safety testing done by OEMs in several different fields where iron phosphate cells burned the same as “unsafe” LiCoO2 cells. Safety is always my first concern at the cells level, unless dictated otherwise, although most of those features fall on the MEs and EEs. The best anyone can do is design to the spec supplied by the customer, add a huge safety margin, and add to that safety trying to anticipate what people might do. That being said, it is impossible to design for every ridiculous scenario that the end user might conceive. You can only mitigate the damage that they will do to the pack and themselves. And I won’t be the least bit offended if you don’t want to do anything that involve cells I have worked on, although there are probably a couple of industries where the odds are ~50:50 that you will have to use them…
“As a matter of fact the tests performed are closer to the charge/discharge limits set by the Model S battery management system in standard mode …”
I don’t know what you consider deep discharge, but the some of the same cells Tesla uses are spec’d to ~300 cycles before reaching 80% capacity under deep discharge (full 100% state of charge to 0% state of charge). Of course, Panasonic could be lying about the data that they supply, but then again, I have run the same testing in the lab and gotten similar results. I don’t think that you misrepresented the data as much as misinterpreted it as to how it applies to automotive. If that degree of capacity restriction, i.e. only using ~40% of the battery, is how they are guaranteeing the Model S battery life, then everyone is really only getting ~34kWh battery. That is the difference between “true” and “usable” capacity/energy. Thermal pack management is done by a number of manufacturers. We have supplied prototypes for a variety of uses that have charge/discharge restriction tied to temperature, at both the high and low end.
My point has consistently been that lab testing is no substitution for real world usage. Tesla has used a lot of pack building and cycling techniques that other manufacturers have used successfully over the past 2 decades to improve safety, extend cycle life, and optimize performance. That being said, lab testing just adds another data point to help improve your case. The jury will be out until a significant number of vehicles are in use for a significant number of miles to be statistically relevant. I am not trying to cast any FUD, just show the real world challenges of pack design for an uncertain usage model, how there is a disconnect between test data and real usage, and the difference between the PR hype and the real world.
“That brings us to the next point. 45,000 miles / 3 years of use…”
There is no guarantee that the pack will have 91% energy left. Some may have 95%, others 80%. That is going to be highly dependent on usage. And I did mean “buy.” Sometimes my hands can’t keep up with my brain. I never suggested that they should pay recycling fees for the pack. My point (again pretty consistently) has been, if there are huge breakthroughs in performance or cost, why would anyone buy a used pack, when a new pack, with better performance could be had at a small premium. Unless they plan on taking a loss on any used packs. If I was a stock holder in Solar City, or a customer, I would be very skittish at the prospect of using a pack of unknown veracity for any purpose.
You quoted Spiderman, so allow me to quote Pulp Fiction. “If my answers frighten you then you should cease asking scary questions.”
The Dark Side Of Tesla's Masterful Short Squeeze [View article]
First let me thank you for not referencing the same tired out Panasonic presentation that everyone spouts off about. Second, I had seen that ECS abstract.
That being said, yes, I will argue such a simple thing, especially when you misrepresent/misinterpret data.
Your link is not the cell spec. It is an abstract for an ECS presentation, which might be the same general chemistry, but is not the same cell (especially since it says 400mAh cells). Those cycles are nowhere in the vicinity of deep discharge. An end of charge voltage of 4.05V corresponds to ~85% state of charge (SOC), while an end of discharge voltage of 3.6V corresponds to ~40% SOC. So in the end they are cycling over ~40% of the available capacity of the cells. Not very impressive in that light. Additionally, as I have noted time and time again, simple charge discharge cycles are not very indicative of how a cell will behave in an EV-type application, which requires higher rate pulses in both the charge and discharge regime often with no equilibrating rest in between. So what you really have is a battery that is probably double in size to ensure that it will still have a lot of range in 5+ years time.
I could care less how it works. The question is WILL it work, and the jury is out as to whether or not used packs of unknown veracity will be good for anything other than a several hundred kg doorstop. That doesn’t even begin to get into, this question:
If the price of batteries drops, or the performance see the order of magnitude increases that everyone screams about, why would anyone by a used battery when a newer, better performing battery can be had for a small premium?
And I didn’t twist what you said. “High residual value of battery makes cheap upgrade path for new tech - i.e. a new battery sale for every model s owner every few years for a few thousand USD.” To me, that says that people are going to be clamoring for a new battery after a couple of years, which they very well might. They are highly unlikely to pay $3500 for it though, since the battery now is probably >$10k in cell costs alone, likely higher.
The Dark Side Of Tesla's Masterful Short Squeeze [View article]
Access to pilot scale equipment (~200k cells/year) would give them access to equipment and that’s it. Then there is the fun bit of having to source all the actual components, which is virtually impossible in some instances unless you have a well defined spec in mind already or an in with the company in question. It would give them in house capability to license and test things from a variety of places, most of which are dead ends. The national labs are particularly harsh about who gets credit for discoveries and are loathe to give up credit or rights to patents.
As for licensing it back, the Japanese are loathe to bring in anything out of house unless it was developed nearby, i.e. in Japan.
I believe John’s comment was that he had heard that Tesla is considering manufacturing the cells themselves, not doing R&D./pilot scale.
While I agree about the research culture in Asia, to a point, the same holds true to many universities and national labs, unfortunately. Many “breakthroughs” in academic settings are virtually meaningless in the real world for the same reasons that you stated about battery research in Asia.
The Dark Side Of Tesla's Masterful Short Squeeze [View article]
There is no evidence of this in real world use or empirically.
There is currently no residual value is used batteries. Lots of people hope that there will be, but there just isn't. Besides, what value is there in a battery that has an unknown heritage in terms of usage other than the number of miles?
As an aside, if the Model S needs a battery upgrade every few years, there will be a lot of pissed off people. Of course, since most of Tesla's battery warranties are of the, "Does not cover normal capacity loss," variety, it wouldn't surprise me one way or another if they need to be replaced.
The Dark Side Of Tesla's Masterful Short Squeeze [View article]
Unless Panasonic has a 18650 manufacturing facility stateside that no one knows about, I don't know if it is even "mostly." The parts may all be put together here, but they definitely come from all over.
Tesla's Q1 Earnings, An Epic April Fools Prank [View article]
I found an error in my calculation. Going from the Panasonic spec sheet, if they are using the highest capacity cell, it is closer to 250Wh/kg. If they are using one of the lower capacity cells, it is in the 225 to 235 Wh/kg range.
The really curious thing is that recently the capacities for the two highest capacity cells has be reduced by about 50mAh each from where they were initially presented at.
Tesla's Q1 Earnings, An Epic April Fools Prank [View article]
At least you and I are in agreement that there is potential for failure in anything.
--Acceptable range—Why does the range have to be >200 miles for it to be successful? All that I ever hear is how most everyone drives <40 miles in a day. It can’t be both ways, i.e. needing to have >200 miles and only needing 80 to 100.
-Weight—Tesla’s pack is so large, they go from ~270Wh/kg at the cell level to ~150Wh/kg at the pack level. This means that there is significant weight added to the pack to make it functional. This is an inherent weakness with the small cell approach.
-Cost—Again, I have never seen hard cost numbers from anyone about ANY OEM’s pack costs, just lots of fuzzy numbers and cell cost numbers.
-Thermal management--This is one area that I think Tesla excels at. That being said, with a different cell choice, they could have lessened the need for this type of management.
-Operational life—TBD. There is not enough statistical evidence to support this.
I don’t know if Tesla has the best battery solution. That remains to be played out. I disagree about unacceptable range, I agree about cost, although that stems significantly from battery costs, and I think even Tesla is TBD for thermal management and operational life. I suspect that Tesla is not nearly as ahead of everyone as you think, but that’s only because I have spoken with enough people at different levels of the battery supply chain to know what some people have in the wings.
Tesla's Q1 Earnings, An Epic April Fools Prank [View article]
"For 30M miles - resolve your skepticism by calling Tesla."
That really isn't the independent verification that I mean, but thanks anyway.
As for Li-ion in a pure EV, I have read a couple of reports from either OEMs and/or the govt about EVs from the 1990s that were highly successful in small fleet testing, but were not pursued because there was no market or economic incentive. I can't speak for Daimler, but I know that Toyota has a very good handle on EV technologies. They don't have any reason to get in the game until costs are to their liking for components, particularly batteries.
My cost comment wasn't directed at you, but since you felt the need to stick in your $0.02... Cost always matters. If better, cheaper batteries are developed, what incentive does anyone have to use old batteries in the mythical "second life" that people so desperately want to believe in? How can Tesla guarantee residual value for something that may be completely obsolete? I have had enough "behind the doors" discussions with people all up and down the supply chain from raw material vendors all the way up to OEMs in a number of industries, and what is said then is not lock step in line with what the PR hacks spout off about.
As for Vegas, I get into the action for the hell of it, but I usually stick to cards, although it is fun to gawk at the suckers.
Tesla's Q1 Earnings, An Epic April Fools Prank [View article]
"Not in automotive. None of the other EVs on the road use the affordable 18650 cells."
Not actually. A number of OEMs have looked at it, but there is a weight penalty using a small cell approach, which they are loathe to take. Same goes with liquid cooling. Additionally, with liquic cooling there is another major failure mode that has to be taken into account. In reality, you could probably make a care with similar range and cheaper. Heck, I even think Tesla could do the same if they made the right cell choice.
Tesla's Q1 Earnings, An Epic April Fools Prank [View article]
I had heard that there may be 30 million aggregate miles. I don't know if that is fact or not since I only have the CTO's word to go on. "Battery incident" could mean anything from simple cell failure or a bad weld to complete catastrophic fire, depending on the source. I am assuming that he means complete catastrophic fire.
As for high power, even Tesla is no where near the realm of high power, even in EV applications. A fast 0 to 60 time does not necessarily mean high power.
Dave_M--
I know what he meant, and he was still wrong. People have been making large arrays of 18650s into larger packs going on 20 years. People have been using active liquid cooling with Li-ion for nearly as long. Their approach is not unique, and is not necessarily lower cost.
Tesla's Q1 Earnings, An Epic April Fools Prank [View article]
"FYI. TSLA invented the battery pack - that now has over 30 Million miles without any incidence - and the electric drive train."
I have never read such a bogus statement before. Tesla invented neither the battery pack (none of which have 30 million miles on them) or the electric drive train. They have taken a number of techniques/technologies that others have developed and incorporated them into their packs/drive train.
"TSLA battery pack proves that Li-Ion can be effectively used in high power applications including Boeing 787 if properly designed."
Pure EV applications are one of the milder applications that Li-ion can be used for. It is nowhere in the realm of high power. It might be high power compared to laptops or cell phones, but is nothing close to most applications. People have been doing high power Li-ion for nearly 2 decades now, and Tesla isn't even in the ballpark.
Are EV Dreams Going Up In Smoke? [View article]
That battery has been in the works for years and just shows that lab testing is no substitution for real world usage. There are only two or three actual usage models where lab testing give a >90% view of what should happen under actual usage. Everything else gets you into the ballpark at best.
Are EV Dreams Going Up In Smoke? [View article]
Yuasa merged with Japan Storage Battery to form GS Yuasa a over a decade ago. JSB was one of the leaders of Li-ion.
Why Batteries Are Too Valuable To Waste On Solar Power Integration And Electric Cars [View article]
Much less has changed in the automotive industry than you would think over the past few years. Many of the same issues that were being looked at the last time EVs were made commercially have cropped up in one form or another this next go around. the different is that the OEMs have a somewhat better understanding this time around. That being said, what is said behind closed doors and what is said in public are two completely different things.
Toyota spends plenty on R&D and they have a very good understanding of the Li-ion space (at least in my dealings with them). I would like to think that they have a pretty good nose for good tech. I wonder why the RAV4 EV would cost so much. It couldn't be because of the batteries could it?
Why Batteries Are Too Valuable To Waste On Solar Power Integration And Electric Cars [View article]
There is no 1C charging in there. It is all at at rates much lower than 1C. The "1C" discharge is also not really 1C. If you look at the two main graphs depicting cycle life, they have very different voltage windows, 4.2 to 2.5 at RT, and then 4.1 to 2.5 at elevated temperatures. Lowering the cutoff voltage can give the illusion of more capacity just as lowering the charge voltage at higher temperature cycling can improve the cycle life.
Fact of the matter is that single cell test data is meaningless as to how a pack will perform, for any application. This is particularly true when comparing simple charge discharge cycles with complicated usage profiles that can be seen with many systems. Until a statistically significant amount of people have a large number of miles, the data is nice, but proves nothing.