Quote:
Originally Posted by IamIan
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I feel like there's a challenge there, ha. Accepted.
You have said that I can't overgeneralize when it comes to different kinds of vehicles. I quote from the NHTSA: "The ability to store and deliver substantial energy onboard a vehicle also implies that substantial
energy can be released, with corresponding hazards, in the case of failure. In this case, the energy
is stored electrochemically in batteries, rather than chemically as a fuel. While systems safety
engineering can achieve levels of safety with Li-ion technology comparable to that of
conventional fuels, the automotive industry does not have decades of experience with it and the
same understanding that it has concerning conventional and alternative fuels".
They have also articulated well what I have been trying to say this entire time about the overall safety of EVs: "The risks associated with Li-ion battery systems derive fundamentally from the novelty of the
technology and limited long-term experience base with its safety performance. Vehicle service is
one of the most diverse and challenging engineering applications because of the diversity of
environments, vehicle users and potential for misuse and abuse. There is limited experience in
understanding how the rigors and challenges of severe vehicle duty cycles affect the long-term
safety of Li-ion batteries and systems. Auto makers and battery manufacturers are working
diligently to ensure that the battery systems being deployed are safe for consumers, but it is an
evolving field. The same was true of natural gas and propane fuel vehicles in the 1990s and of
hydrogen fuel vehicles in the 2000s".
In essence, I am wary of the technology right now because of the inexperience we have with it. The media has spun some negativity on the technology and I see some truth to it. The ICE industry has the advantage of being around for 100 years. We have a very good idea on what causes a fire in an ICE. EVs have some unknowns still.
These are some of the things that can cause fires, or "thermal runaways": Perhaps best known of the potential failure mechanisms of Li-ion batteries is thermal runaway in
which external short circuits, internal short circuits, cell overcharging, cell over-discharging,
physical abuse such as crush, or exposure to high ambient temperatures can each potentially
cause overheating of a cell and initiate thermal runaway events, or weaken the cell such that it is
more prone to thermal runaway (Arora, Medora, Livernois, & Stewart, 2010; Brenier,
McDowall, & Morin, 2004). Once initiated, thermal runaway is self-propagating failure within a
cell, a series of cells, an array or module, or even beyond the enclosure to the vehicle. Thermal
runaway is most likely to be realized when an event occurs that results in rapid heating of the cell
that outpaces the rate of heat dissipation in the cell. Adiabatic self-heating can be caused by
thermal (e.g., radiant heating), electrical (e.g., short circuiting), or physical (e.g., compression)
external effects".
There are many failsafes in EVs to try to prevent this, but this can still happen despite preventative measures given the correct conditions.
There is a reason why batteries are supposed to be replaced after a certain timeframe, and this is it: "Battery failures that lead to sub-optimal performance and degradation can often be traced back to
aging mechanisms within the cell. The cathode and the anode age differently, and the majority of
aging in the system takes place at the interface of the separator, the electrolyte, and the cathode
or anode. Aging at either electrode can lead to a change in its properties that varies with both
calendar time and use. During storage, self-discharges and increasing impedance can shorten
shelf life. In addition, trace contaminants, such as water and iron, can have significant effects on
the degradation. The cycle life is typically influenced by stress induced degradation and lithium
metal plating".
Battery life isn't just about the battery capacity. Using old batteries is basically driving on borrowed time; the chance of thermal runaway or a short circuit is dramatically increased.
This is an explanation of what happened in the Rich video: If not prevented or mitigated, the causes and contributors to damage and failure at the cell level
can result in uncontrolled exothermic reactions and heating and pressure rise within a cell, i.e.
thermal runaway. If thermal runaway cannot be controlled or mitigated through measures such as
thermal shutdown separators, then the cell may vent, creating local overpressure and releasing
combustible solvent vapors that may ignite and burn, the primary hazards of cell failure. If
pressure relief protections are not present or fail, then cells may rupture, potentially also
releasing hot particles and projectiles. If the failures do not propagate beyond the cell, then these
primary hazards may be contained within the casing of an array or module".
As we have seen and read in the news, this is not always contained in the battery casing, such as in a vehicle crash.
So, will the EV overtake and eventually replace the ICE?
I don't think so. And many experts in the field are also skeptical that they will be overtaken and replaced. If you compare a new vehicle today to a vehicle made in the 70s, you will see a huge difference in efficiency and emissions. Who's to say the trend won't continue? One big factor for EV supporters is the cheap price of electricity. Electricity will not be so cheap if you take out the fossil fuel factor, and when you add in a huge additional load from electric powered vehicles.
As far as what you have said about stationary ICEs being replaced, I wouldn't be so certain of that. Most managers (especially American managers) suffer from managerial myopia; they choose the short term gain rather than investing for the future. New equipment is expensive. For a very long time it will be cheaper to repair existing equipment. That is why we still see 50 year old equipment in use today, when new equipment is more energy efficient and shinier.
Biofuel:
When you think of it, we are already supplementing a large portion of our fuel with biofuel.
https://www.epa.gov/environmental-ec...omics-biofuels
After doing some research (including reading a scholarly paper), my sources have not really presented any major reason why we are not using cellulosic biofuel. Would someone like to share? The major reason the paper presented is that it would compete with people who want firewood, etc. But there is a lot of waste in this country.
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