this post was submitted on 03 Jul 2023
2 points (75.0% liked)
Technology
59674 readers
3028 users here now
This is a most excellent place for technology news and articles.
Our Rules
- Follow the lemmy.world rules.
- Only tech related content.
- Be excellent to each another!
- Mod approved content bots can post up to 10 articles per day.
- Threads asking for personal tech support may be deleted.
- Politics threads may be removed.
- No memes allowed as posts, OK to post as comments.
- Only approved bots from the list below, to ask if your bot can be added please contact us.
- Check for duplicates before posting, duplicates may be removed
Approved Bots
founded 1 year ago
MODERATORS
you are viewing a single comment's thread
view the rest of the comments
view the rest of the comments
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 fundamental 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. At 10%, it is 3,333 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