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[DonTom]

Or is this just more EV battery vaporware?


"A higher-performance version is still under research and development but has the potential to deliver 50% more cruising range — over 900 miles, according to Toyota. That could get you from New York to Chicago and then some, and charge time would be just 10 minutes."


-Don-  Reno, NV

[Fran K]

It is probably a bit overly enthustaic writer.  It is probably the same semi solid state that has been discussions about,  Toyota seems to have their own in house engineering team.  Going to need more than 50% more range than what the 2024 model will do?  That won't be 900 miles on I80or I90 will it?

[Oilcan]

It’s vaporware if it came from Toyota. They don’t build BEV’s. Why would anyone need an EV to go twice as far as an ICE vehicle anyway. Can you imagine the heat generated charging a battery that fast.

[MyFirstElectric]

It’s vaporware if it came from Toyota. They don’t build BEV’s. Why would anyone need an EV to go twice as far as an ICE vehicle anyway. Can you imagine the heat generated charging a battery that fast.

That's exactly my point also! All the folks who are fast-charging their EVs all the time, RUIN their batteries. It's chemical science. Nothing to feel surprised about.

I can understand the one-off fast-charge when someone is stuck on a long trip and short of time. But doing that as a rule, is foolish squared.

Of course those running fast chargers (incl Tesla) don't like to admit that, but everyone in the industry knows.

It's not only the heat that causes problems. It's the fact that electrons don't move fast enough through the electrolyte from the cathode to the anode, and so oxidation at the anode increases.

Likewise, it's foolish to charge a battery to full and keep it there, for the same reason. If you're not planning to use the power, then charge only to ~70%. Charge to full only before you will be discharging the EV on a drive/ride.

Next, don't charge immediately after discharging (coming home). Let the battery cool down first for half an hour minimum. Same after charging, let it cool down for half an hour.

The most striking of all the research papers I read was the one that summarized: it's far better for longevity to run a battery empty, than to charge it to full - ever. That surprised me so much, I still remember it like I read it yesterday (it was long ago). I should go looking if now more such research exists. I haven't had the time though.

[DonTom]

The most striking of all the research papers I read was the one that summarized: it's far better for longevity to run a battery empty, than to charge it to full - ever. That surprised me so much, I still remember it like I read it yesterday (it was long ago). I should go looking if now more such research exists. I haven't had the time though.

But is that for safety reasons or for battery life?


The reason I ask, is just today, on Xmas, I received my $1,400.00 because of this.


But AFAIK, all the Bolt fires were at the very end of the charge at 100% SOC after a charge from near 0 SOC.


Since the current is lowest at the end of the charge, what it is that causes the batteries to blowup?


And how come it only seems to happen while charging and never while driving when the current draw from the battery is sky high?


FWIW, I have a hard time buying it's better for the battery to stay discharged than fully charged. Discharged can permanently ruin the battery in a couple of days or so, unlike fully charged.  In fact, many vehicles will void the battery warranty if left at 0 SOC for more than 24 hours. I fact, IIRC, it states such with the Zero Battery warranty.


But I have never heard of a warranty being even reduced because of charging to 100%.


-Don-  Auburn, CA

[Specter]

Dendrites, internal shorts, taking rest of the attached packs with it.  Also when fully charged and you keep adding electricity to it, the voltage will spike very quickly.  BMS systems typically are woefully under engineered, they do the very basic to pretend to keep the battery alive, however most of them, their  auto shutoff point is already so far into the red volt wise it's pretty much too late, the damage is started / done.  If you have an imbalanced cell / branch-arm, THAT is what will cause the catastrophic failure, it will push that pack so far past it's danger point it just gives up the ghost.

aaron

[DonTom]

Likewise, it's foolish to charge a battery to full and keep it there, for the same reason.

I was just thinking (danger!):


Here we have to define "full" as "full" is well above 100% SOC. That is why we have a max capacity and a useable capacity. Same issue below 0 SOC as we can usually still drive/ride a little below 0% SOC as well.


The Zero DSR/X will let me go a bit more into the max capacity and will show as 110% charged. Of course, even 110% is well below true max "full".


We normally think as "full" as 100% SOC. As that is full in most cases to the EV owner.


But if we really could charge to the very max, it probably then is true that charging to "full" is worse than fully discharged, but again, we also need to define what "fully discharged" as well, as that is below 0% SOC.




-Don-  Auburn, CA