Eric Gagen + 713 May 27, 2021 1 hour ago, ronwagn said: Thanks for that. America has become a real laggard in preparing for worst case possible scenarios. China and, probably Russia are ahead of us in all such things. They are realists not head in the sand optimists. Being naive and hopeful is not a good defensive strategy! Russia isn't likely ahead of the US in this - rather they are more willing to suffer the consequences. If Russia ever gets hit by a massive EMP it will be fine so long as there is vodka, and firewood still available. The rest they can sort out as they go, and the average Russian is willing to live with that possibility. After all their society collapsed due to other causes a few times in the last 100 years and they made it work Hopefully we can be just as resilient but it's never been tested. 1 Quote Share this post Link to post Share on other sites
Eric Gagen + 713 May 27, 2021 5 hours ago, Dan Clemmensen said: As I said above, the problem is with the way the word "battery" is being used. In an EV, the "battery" is a rack full of modules and each module is a set set of cells. With a "structural battery", the rack is part of the structure of the car, and the modules are just loaded into this structural rack unit. The modules are not structural. In real life most folks would call a module a "battery", and say that the EV has multiple batteries. BTW this sloppy terminology is not new. A WWII submarine had a "battery" consisting of one or more rooms full of lead-acid batteries. All of this confusion happens because the word "battery" actually means "collection of sub-units". A module is a collection of cells. An EV battery is a collection of modules. An artillery battery is a collection of artillery pieces. To further confuse matters, the structural battery rack is one of two uses of the term "structural battery", and it is the one that is currently being implemented by Tesla. The other use of the term is for more exotic applications where things like roof and side panels are somehow magically turned into batteries. I will believe that one only if it actually gets into production. I agree, but I purposely tried not to jump into this mess of terminology. there are improvements to be made, and I expect they will happen as battery electric vehicles 'go mainstream' and more minds and money get put into them. It's just not going to lead to as big a change as some people might expect. Improvements in the construction of the individual cells of the battery system are more likely to lead to significant weight losses IMHO. 1 Quote Share this post Link to post Share on other sites
footeab@yahoo.com + 2,190 May 27, 2021 4 hours ago, Strangelovesurfing said: Lot's of epoxy covered rebar is used where I live. Corrosion levels are very high in the tropics. Epoxy rebar is horrible for corrosion. It is being banned in the USA, Europe, Japan, etc for all structural applications. Non structural it is still sold and used. So, same would apply in the tropics. Why? The paint chips and leaves no protection at all in the most important areas and has led directly to several bridge/road failures. Bending rebar causes epoxy to flake off Can't weld it, as it must be ground off, cleaned, and repainted... just does not happen Just transporting it and rubbing against its neighbors creates wear points that have no epoxy It cracks all by itself due to temperature differentials if left in the sun(Ok, this point was fixed a long time ago, but if you have a bad batch of paint... applied) Construction has turned to heavier galvanizing which allows you to bend the rebar to your hearts content and for the most part, just more concrete in thicker sections as this eliminates most of the oxygen penetration to the steel rebar to begin with. The exceptions are high salt content environments, or environments with high water transport of oxygen, everyone has gone to fiberglass, stainless steel,and upcoming is silicon based rebar(modified glass really but with lots of additives) Quote Share this post Link to post Share on other sites
Strangelovesurfing + 737 JD May 28, 2021 (edited) 4 hours ago, footeab@yahoo.com said: Epoxy rebar is horrible for corrosion. It is being banned in the USA, Europe, Japan, etc for all structural applications. Non structural it is still sold and used. So, same would apply in the tropics. Why? The paint chips and leaves no protection at all in the most important areas and has led directly to several bridge/road failures. Bending rebar causes epoxy to flake off Can't weld it, as it must be ground off, cleaned, and repainted... just does not happen Just transporting it and rubbing against its neighbors creates wear points that have no epoxy It cracks all by itself due to temperature differentials if left in the sun(Ok, this point was fixed a long time ago, but if you have a bad batch of paint... applied) Construction has turned to heavier galvanizing which allows you to bend the rebar to your hearts content and for the most part, just more concrete in thicker sections as this eliminates most of the oxygen penetration to the steel rebar to begin with. The exceptions are high salt content environments, or environments with high water transport of oxygen, everyone has gone to fiberglass, stainless steel,and upcoming is silicon based rebar(modified glass really but with lots of additives) They're still using it in my neck of the woods. I see it all the time on roadway and support structures used in our new light rail monstrosity that's never going to be completed. https://www.civilbeat.org/2021/01/for-the-honolulu-rail-project-2020-was-the-year-the-wheels-fell-off/ https://www.staradvertiser.com/2021/05/13/hawaii-news/problems-piling-up-for-the-honolulu-rail-project/ That damn project is going to bankrupt the city and county over here, by the time it's finished we'll have flying cars. City and County workers = Sitting and Counting the minutes workers. Edited May 28, 2021 by Strangelovesurfing Quote Share this post Link to post Share on other sites
footeab@yahoo.com + 2,190 May 28, 2021 7 minutes ago, Strangelovesurfing said: They're still using it in my neck of the woods. I see it all the time on roadway and support structures used in our new light rail monstrosity that's never going to be completed. https://www.civilbeat.org/2021/01/for-the-honolulu-rail-project-2020-was-the-year-the-wheels-fell-off/ https://www.staradvertiser.com/2021/05/13/hawaii-news/problems-piling-up-for-the-honolulu-rail-project/ That damn project is going to bankrupt the city and county over here, by the time it's finished we'll have flying cars. City and County workers = Sitting and Counting the minutes workers. THey might have gone with prebent galvanized and then epoxy coated. Of course this still has the problem of construction crews banging them around. It also might just be a new paint over galvanized rebar or all of the above instead of stainless steel or Fiberglass.. https://galvanizeit.org/knowledgebase/article/painting-over-galvanizing You will also notice that all railway/bridge structures pillars now have their exterior concrete painted. This keeps the oxygen out as well as water for freeze/thaw cycles which creates the cracks allowing yet more oxygen in... obviously not a problem in Aloha. 1 Quote Share this post Link to post Share on other sites
Rob Plant + 2,756 RP May 28, 2021 (edited) 12 hours ago, Eric Gagen said: I agree, but I purposely tried not to jump into this mess of terminology. there are improvements to be made, and I expect they will happen as battery electric vehicles 'go mainstream' and more minds and money get put into them. It's just not going to lead to as big a change as some people might expect. Improvements in the construction of the individual cells of the battery system are more likely to lead to significant weight losses IMHO. Turbguy said "Until someone determines how a battery can also form the STRUCTURE of a vehicle, battery weight will be a negative. If we could store charge in the frame, panels, glass, seats, etc, then there would be, in effect, "weightless" batteries. But...I'm not holding my breath." @turbguy + @Eric GagenThese guys have had a breakthrough in this. https://www.sciencedaily.com/releases/2021/03/210322091632.htm Edited May 28, 2021 by Rob Plant Quote Share this post Link to post Share on other sites
Eric Gagen + 713 May 28, 2021 (edited) 1 hour ago, Rob Plant said: Turbguy said "Until someone determines how a battery can also form the STRUCTURE of a vehicle, battery weight will be a negative. If we could store charge in the frame, panels, glass, seats, etc, then there would be, in effect, "weightless" batteries. But...I'm not holding my breath." @turbguy + @Eric GagenThese guys have had a breakthrough in this. https://www.sciencedaily.com/releases/2021/03/210322091632.htm Quite frankly, no they didn't. Their claim is that their battery has 24 Watt hours per kilogram of battery weight. The problem is that conventional Lithium ion batteries for automotive use are between 4 and 10 times as energy dense: https://www.cei.washington.edu/education/science-of-solar/battery-technology/#:~:text=Compared to the other high,-670 Wh%2FL). "Compared to the other high-quality rechargeable battery technologies (nickel-cadmium or nickel-metal-hydride), Li-ion batteries have a number of advantages. They have one of the highest energy densities of any battery technology today (100-265 Wh/kg or 250-670 Wh/L)" the researchers you cite are promising future improvements which may be possible: "Now, a new project, financed by the Swedish National Space Agency, is underway, where the performance of the structural battery will be increased yet further. The aluminium foil will be replaced with carbon fibre as a load-bearing material in the positive electrode, providing both increased stiffness and energy density. The fibreglass separator will be replaced with an ultra-thin variant, which will give a much greater effect -- as well as faster charging cycles. The new project is expected to be completed within two years. Leif Asp, who is leading this project too, estimates that such a battery could reach an energy density of 75 Wh/kg and a stiffness of 75 GPa" If and when they achieve them, then they would be getting into a workable range with respect to power density and weight (assuming no improvements in competing technologies. Then all they have to do is overcome the cost and manufacturing challenges associated with having a large chuck of their battery made out of carbon fiber. They are still a long way from having a workable product, and even the researchers in your article acknowledge that. Quote Edited May 28, 2021 by Eric Gagen Quote Share this post Link to post Share on other sites
Rob Plant + 2,756 RP May 28, 2021 (edited) 1 hour ago, Eric Gagen said: Quite frankly, no they didn't. Their claim is that their battery has 24 Watt hours per kilogram of battery weight. The problem is that conventional Lithium ion batteries for automotive use are between 4 and 10 times as energy dense: https://www.cei.washington.edu/education/science-of-solar/battery-technology/#:~:text=Compared to the other high,-670 Wh%2FL). "Compared to the other high-quality rechargeable battery technologies (nickel-cadmium or nickel-metal-hydride), Li-ion batteries have a number of advantages. They have one of the highest energy densities of any battery technology today (100-265 Wh/kg or 250-670 Wh/L)" the researchers you cite are promising future improvements which may be possible: "Now, a new project, financed by the Swedish National Space Agency, is underway, where the performance of the structural battery will be increased yet further. The aluminium foil will be replaced with carbon fibre as a load-bearing material in the positive electrode, providing both increased stiffness and energy density. The fibreglass separator will be replaced with an ultra-thin variant, which will give a much greater effect -- as well as faster charging cycles. The new project is expected to be completed within two years. Leif Asp, who is leading this project too, estimates that such a battery could reach an energy density of 75 Wh/kg and a stiffness of 75 GPa" If and when they achieve them, then they would be getting into a workable range with respect to power density and weight (assuming no improvements in competing technologies. Then all they have to do is overcome the cost and manufacturing challenges associated with having a large chuck of their battery made out of carbon fiber. They are still a long way from having a workable product, and even the researchers in your article acknowledge that. I never stated they had a "workable product" I said they had made a breakthrough, which they have. Glass half empty??? Jeez Edited May 28, 2021 by Rob Plant Quote Share this post Link to post Share on other sites
Eric Gagen + 713 May 28, 2021 12 minutes ago, Rob Plant said: I never stated they had a "workable product" I said they had made a breakthrough, which they have. Glass half empty??? Jeez I'll rephrase - I don't think they made a breakthrough. It's interesting research, but I wouldn't qualify it as a breakthrough. They should keep at it though, because they might in fact have a breakthrough at some point which makes their research more widely relevent, and useful to other research teams. Quote Share this post Link to post Share on other sites
Rob Plant + 2,756 RP May 28, 2021 6 minutes ago, Eric Gagen said: I'll rephrase - I don't think they made a breakthrough. It's interesting research, but I wouldn't qualify it as a breakthrough. They should keep at it though, because they might in fact have a breakthrough at some point which makes their research more widely relevent, and useful to other research teams. That's more like it Eric and a fair assessment! Small steps and we'll get there eventually! Quote Share this post Link to post Share on other sites
footeab@yahoo.com + 2,190 May 28, 2021 (edited) 11 hours ago, Rob Plant said: Turbguy said "Until someone determines how a battery can also form the STRUCTURE of a vehicle, battery weight will be a negative. If we could store charge in the frame, panels, glass, seats, etc, then there would be, in effect, "weightless" batteries. But...I'm not holding my breath." @turbguy + @Eric GagenThese guys have had a breakthrough in this. https://www.sciencedaily.com/releases/2021/03/210322091632.htm Wow, 100% certified Bull Shit rating. That is low grade epoxy. Jeez, does no one know what 25GPa means? They tried slipping the words CF into the article... CF with literally 50X higher at minimum for complete crap CF and upwards of 100X for ordinary CF and upwards of 150X for ultra high tensile CF... before talking carbon nanotubes Then their gargantuan lie about Energy density with 10X difference making even lead acid look good. Any battery with a aluminum shell will have these bulk structural properties... Great, it is not as poor as lead acid. No different than NI-Cd which is actually much higher in BOTH energy density and tensile/compressive strength. There are many silver chemistry batteries with much higher strength and energy density. Got some more 100% certified BULL SHIT to peddle? PS: They also lied about being as strong as aluminum at their theoretical maximum.... That would be UN hardened aluminum and since ALL aluminum used structurally has been heat treated to 6X that strength they think they can get to.... Do yourself a favor NEVER trust ANYTHING out of Science Daily. They are blatant LIARS or utterly IGNORANT yet claim to be peddling "science" Edited May 28, 2021 by footeab@yahoo.com Quote Share this post Link to post Share on other sites
Rob Plant + 2,756 RP June 1, 2021 Nice to see your positivity shining through once again 😅😅😅 Lets all just give up and not try anything new because its all 100% BS if we do! How's that cave of yours doing? Quote Share this post Link to post Share on other sites