Most of us have no basis for evaluating the quality of kids education.
I grew up under the (basically) Soviet education system. I can tell that it's waaaaay better than the average K-12.
One easy fix? Have a high stakes gaokao-style exam for the US students. SAT/ACT are about as tough as a wad of toilet paper.
It's the classic right wing trick where you take a government program that's working just fine and maybe needs a few touch ups and then yank all the funding while methodically sabotaging it in devious ways and then tell everybody, see we tried to have public services but she just can't do it like the private sector can.
The K-12 system in the US has failed. The conservative fix here is absolutely right: institute a voucher system, with the Federally guaranteed funding level, and let parents choose schools. With obvious allowances for students with special needs, rural areas, etc.
It's quite clear that regulation is getting nowhere fast. Even the milquetoast Common Core requirements resulted in a revolt from schools not able to teach even basic literacy.
The same thing is especially important for BEV's !
The battery heater in BEVs does NOT use water-based coolants at all because of the risk in case it leaks. Instead, they use glycol. Tesla even has a sensor that will disable the HV battery if it detects a conductive liquid in the battery loop.
Given the mass of a typical EV battery it might not be enough to have a 120 volt 15 amp outlet like that used for the typical block heater to get the battery warm enough for maximum range.
Let's get some chemistry to help!
On average, the rate of chemical reactions goes up by 2x for every 10C of temperature increase. If your battery is at -20C then it produces about 12 times less energy than at 15C. A typical car battery can produce about 300kW of power, so that still leaves you with 25kW (or 33 horse power). A typical battery is about 400kg for the cells themselves, and apparently the cells have specific heat capacity of 800 J/kg/C, so heating them at 25kW will require 448 seconds.
But heating the battery _improves_ the discharge rate, so you get a nice differential equation. If you solve it, the resulting time is around 240 seconds or 4 minutes.
In reality, modern EVs drive just fine in Midwestern weather without ANY pre-heating. You get very sluggish performance for the first ~10 minutes while the battery warms up, but the car is perfectly drivable.
A 2020 Model 3 has 65% capacity at 15F outside temperature, according to the linked study. In 2021 they replaced the resistive heating with a heat pump, so it only goes down to 67% range.
This study is BS. I have a 2018 Model 3 with resistive heating, and I did many road trips in sub -20C conditions. Heating a cold-soaked battery from that temperature to 10C takes about 5kWh, or around 7% of the total capacity. You typically can do that on "shore power" while the car is plugged in but you can do that unplugged. After that the battery gets enough heating from its internal inefficiencies.
The major energy sink is actually heating the _cabin_. People tested driving a Tesla Model 3 at -20C without any heating, and the range is around 86% of the normal.
So the range impact has NOTHING to do with the "battery chemistry" or "fundamental problems with lithium". It's just a question of using more energy to drive a given distance. Good news is that it can be solved by just making the battery larger.
TIOBE gets its data by searching for "$LANGUAGE programming" in various search engines, and applying some magical scaling factors.
It's complete nonsense and has no relationship to actual real world usage.
Let's be honest, EV drivetrain design isn't exactly cutting-edge science.
LOL. A simple EV drivetrain is easy. A modern EV? It's an engineering work of art, with specialized power electrics, electric motors with power density that is insane, etc.
A lot of complexity is not apparent to classic mechanical engineers, but it's no less real. If anything, it's the gasoline engines that require no real expertise anymore.
I also think you overestimate the value of teaching to a standardized test is.
No, I'm not. Studying any topic is hard work that requires a lot of exercise and practice. And you need objective criteria to measure your progress. You can do competition-style measurements, where you pit yourself against other people. But it's not practical for math. So you're only left with "track running" style measurements, i.e. testing.
No Child Left Behind - teach test taking, rather than subject matter or how to think.
Oh, do fuck off. The teach-to-test is FINE for math. In fact, it's the absolutely best way to teach it. It's just that the tests _themselves_ have the consistency of wet toilet paper. And since they keep showing just how bad the US education is, they keep getting even mushier: https://newsroom.collegeboard....
Bring gaokao to the US!
Wanna bet that their business plan, much like Solyndra's business plan back in the day, was based on nearly endless supplies of government-backed money to fund their business when rational investors wouldn't...
Their business plan was to develop sodium-ion batteries. This requires a lot of speculative research, which requires time and money. Meanwhile, Chinese CATL launched a new sodium-ion battery line. And BYD is building a $2B sodium-ion factory right now.
In 5 years, the US will face international battery competition from two fronts: solid-state batteries for high-performance cars and electronics, and sodium-ion batteries for grid-scale projects and cheap cars. With thousands of patents protecting all the important technologies.
And the US answer will likely be a new purple-colored F250 with even lower fuel economy and built-in coal-roller.
The next person to mention spaghetti stacks to me is going to have his head knocked off. -- Bill Conrad
