this post was submitted on 22 Feb 2024
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[Dormant] Electric Vehicles
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Batteries are more complex. A 200lb battery is less complex than 1000lb or 2000lb battery.
EDIT: I'm an electrical engineer. I can prove to you the complexities of a modern EV Battery. Or do you think 400V systems composed of parallel transistors, battery-management systems, and a whole slew of literally fucking computers estimating the internal-state of the thousands of individual cells that compose a modern EV is a "simple" task?
EDIT: Do you know what kind of degrees you need to design a battery-management system? To mass produce those circuit boards? And to do it all over again 2 years from now when all the chemistries change and therefore the internal estimates of each of these cells completely and drastically changes? No? Please stop pretending that "Batteries" are simple.
Case in point: it's the battery that will most likely fail in ALL of the discussed designs here. Why? Because chemistry is incredibly difficult and hasn't been solved yet. I do await for the future improvements in the EV battery pack that are sure to come over the next few years and decade... But let's not pretend that anything is done R&D yet.
The gasoline engine? Okay we're up to Atkinson cycle so that's a bit different but was around in the 1800s anyway. Nothing is really new or complex here. The engines mechanics were understood nearly two centuries ago.
There's a reason why gasoline engines are so reliable, while batteries keep having faults. Complexity has a lot to do with it.
If only computers existed and had timers that automatically burned off stale gasoline.
Also, just fill up 2 gallons or so to minimize the stale gasoline effect. You'll only be filling up once or twice a month with all the EV driving you'll be doing in practice.
No. The 800+ to 1500+ extra lbs of battery you lug around with a full 300mi electric car is what's actually being wasted in practice.
What do you mean with batteries will fail?
I mean just that.
The internal chemical structure of Li-ion is only designed to work for a limited number of charge/discharge cycles. As the chemistry is stressed out, the internal metals begin to form dendrites (or in more simple terms, spikes) internally.
We have reasonable estimates for how long this takes, but everyone's battery pack is different. And the process is invisible (you have to cut open & destroy a battery to figure out how much of these dendrites or whatever have formed). So the best we got are some computers slapped on the outside of the battery pack that measures temperature, voltage, current, and time to guestimate the effects from the outside.
As cells fail, modern BMS systems will reroute power away from degenerated cells. Its not that the problem was solved per se, its that modern battery packs have a bunch of extra cells waiting in reserve to pretend that nothing has happened to the end user. But this process eventually breaks enough cells that the whole pack fails and inevitably needs replacement.
Exactly when depends on how many cells were left in reserve, how much "fast charging" you do (which is extremely harsh on the internal chemicals), the temperature of the pack under use, and any aggressive driving you might do that heats up the pack more than usual.
Its... really complex. There's a lot of research going on right now to try to stop these dendrites from forming.
EDIT: In any case, Consumer Reports reliability surveys on various parts of say... a Toyota Prius Prime or other PHEVs. Go look at them all, see what parts fail. Its the battery.
Here's GM Volt. What's the problem? Oh, the EV Battery again, and looks like the EV Charger is also terrible cause GM must have messed that up too.
But yes, its the electrical parts that are more complex and prone to failure in almost all of these cars.
Here's Chrysler Pacifica. Oh boy, lots of parts of this vehicle is terrible. But as predicted, the EV Battery is among the worst of parts again.
.... chrysler what are you doing
That Chrysler Pacifica is one of the few electrified solutions with 7 comfortable seats.
Despite that terrible reliability, its one of your best family-van options if you care about electrification at all. You just gotta grin and bear it.