this post was submitted on 03 Jul 2023
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I think the point that is counter to yours is that we are nowhere near the fundamental limits of energy density for batteries. It's probable we are near a fundamental limit for LiPo, but the point is that battery tech improves by changing technologies/chemistries. BEVs couldn't exist at all when the best rechargeable battery tech was lead-acid, but were enabled by LiPo. Theres most likely a type of battery you can't even imagine that has yet to be invented that could store >10x or more energy than current LiPo per unit cost or mass.
I would say that's pretty unlikely there will be a 10x improvement in battery chemistry. At some point, we will have to deal with the fundamental limitations of the technology. That will likely imply a different kind of EV. Other conversations in this thread have brought up the FCEV, which is honestly the mostly likely guess for what comes after the BEV. In other words, the solution is to move beyond batteries, not pretend we can just improve batteries ad absurdum.
Also, this is basically the point of the book The Innovator's Dilemma. Technology does not improve linearly exclusively. At some point, major shifts in the market will have to happen. If you think about this problem honestly, you probably have to conclude that the limitations of the BEV must be solved by a big leap forward, not incremental improvements in batteries. And if you can reach that conclusion, then you must realize that the BEV has to be a transitional technology. Perhaps, even a fad.
If we're talking approaching fundamental limits, Hydrogen fuel cell is not a great comparison. A high pressure tank can only get so light, even with linerless ultra high strength carbon fiber pressure vessels, the mass of the vessel is maybe 6-10x the mass of the hydrogen it carries. To increase specific energy there you need to go to cryogenics which is a whole technology leap and has its own set of challenges.
Battery tech has been improving more than you have seen, clearly. Since '08, lithium batteries have increased energy density by 8x (https://www.energy.gov/eere/vehicles/articles/fotw-1234-april-18-2022-volumetric-energy-density-lithium-ion-batteries). The best LiPo batteries are around 0.9MJ/kg right now, but there's no fundamental reason a battery couldn't achieve 9MJ/kg. Lithium-air batteries could theoretically achieve way higher energy density than that even (https://en.m.wikipedia.org/wiki/Lithium%E2%80%93air_battery), and have already been demonstrated in a lab to achieve more than 5x what current commercial automotive batteries are doing.
Except those fundamentally limits are far higher. The fact is that hydrogen stores energy at 120 MJ/kg. Even at 5% weight efficiency, that's 6 MJ/kg. Or 1,666 Wh/kg. Far beyond any battery.
Your link is seriously lying. 8x is the gap between lead-acid and li-ion batteries. The claims are simply impossible. The author must be unknowingly comparing lead-acid battery powered cars to li-ion battery powered cars. I cannot see any other way his claim is true.
A lithium-air battery is literally a fuel cell. In fact, what did you think hydrogen fuel cells were this entire time?
Driving with something that power dense is incredibly dangerous. You're literally driving a bomb, dynamite is 4.6 MJ/kg
Gasoline is 46 MJ/kg
On one had we've got links to the department of energy and to Wikipedia. And just some hand waving on the other hand.
It's wrong because li-ion batteries at the time were way better than what it claims:
https://news.panasonic.com/global/press/en091218-2
This is from 2009, and already we reached 675 Wh/L. So there's no way the DoE link is true.
Calling them BEVs is misleading and damaging to EVs as a whole, because you're right, batteries do have their limitations, at least today's batteries. The proper industry term is FEV, fully electric vehicle. Choosing to limit EVs to only batteries is an arbitrary decision made for argument's sake, but instead of looking at how they can be improved, you're just focusing on why it'll fail. A "battery" is anything that stores energy, not just the traditional battery, and once EVs are the norm, they probably won't be using LiPos, they'll be using something that hasn't been invented yet.
Are you talking about FCEVs? You can also include directly electrified vehicles, but that is mostly mass transit.
And yes, electrification as a whole will succeed. But BEVs probably are not. I call them fads because they are just toys for the rich and they are unlikely to be affordable for most people.