I’ve always thought phase cancellation technology could potentially be crazy revolutionary. Seems these guys know what they’re doing, but the real challenges come with high decibel levels if I remember right.
If you tried to phase cancel out the sound of a jet engine, it would work and you wouldn’t hear it, but you could also have easily just burst your eardrums too, because the sound pressure level is still present, even if the actual sound is inaudible. It’s a crazy phenomena.
Edit: the sound pressure level IS cancelled out by destructive wave interference, but if this is knocked even by a matter of milliseconds, the wave is doubled and that’s not good for anyone.
Also, on retrospect, phenomena was poor word choice. It’s physics.
The waves are canceled (i.e. gone) until something goes wrong. You could end up accidentally causing constructive interference, in which case you my double the sound’s amplitude.
I feel like this doesn’t happen very often though. I mean I wear sound canceling headphones all the time and I’ve never noticed it accidentally making anything louder. Then again, I don’t normally stand near jet engines.
I wouldn’t imagine noise cancelling headphones would have the ability to output high enough for serious damage. But some people do experience discomfort and pressure when using noise cancelling headphones for the first time, this could be due to a number of factors though.
Yes, sorry, I didn’t phrase that well at all. The sound pressure is actually cancelled out, but with the hypothetical example of the jet engine, anything going wrong could double the dB level instead of cancelling, and because we’re talking milliseconds difference, it would be quite easy to go wrong in this sense.
Besides what you mention, I have my reservations about ‘crazy revolutionary’. If I remember correctly, noise cancelling only works in one very concentrated spot where the waves are measured and cancelled out. If you move a couple of inches, the cancellation isn’t perfect anymore and does practically nothing. That’s why ANC headphones work well (always right by your ear) but any other open application seems implausible to me.
Absolutely, this is spot on, but if they can find ways to work around this like with these microphone swarms they’re proposing, then there could be a lot more applications for it. Some quite scary.
You’re right. Without a demonstration I don’t believe it works. Could be a misunderstanding on the part of the author trying to interpret what the inventors are saying…
Yes when the path between the noise and the noise canceling is out of phase the sound will be lower when they are in phase it will be amplified. Their canceling speakers will need to be very directional to stop this from happening
The cafes would not want that because guests are expected to leave and make room for new ones after some time. That’s also why they crank up the music in these places.
The thing is, we dont generally needed the noisy table muted, we just need it reduced in volume enough at our own table so we are able to carry out a normal conversation
As an autistic person this technology could actually allow me to access the community without being overwhelmed. This is revolutionary and would change my life.
It’s the presentation of the information that really matters. Even if it’s not effective, a water based battery proof of concept is still better than nothing. Just because it isn’t practical right now doesn’t mean it isn’t noteworthy.
The issue is presenting it with the implication that it’s a ready to use product.
Did I miss that or are you saying it rhetorically? I didn’t pull the actual scientific article but this one mentioned decent performance over 800 cycles and 100 mAh/g. I’m not really up on this kind of tech but that seems pretty nifty for a new chemistry .
If you were just being rhetorical I get the frustration. There’s always gremlins hiding somewhere.
Still, I take stuff like this as indicitive that were absolutely not going to be stuck with Li ion forever.
This sounds like it’s worth the hype to me. It has about the same energy density as lithium-ion, and it uses non-toxic and abundantly available materials (unlike lithium-ion).
The cycle count is a little poor but it’s in the ballpark of lithium-ion, is likely to get better, and is much less of an issue if the batteries are non-toxic.
Also… the fact it’s non toxic could effectively reduce the weight especially for small batteries (where they’re still not safe enough despite heavy enclosures - kids literally die after swallowing coin cell lithium batteries).
I’d say worth discussing but none of these articles are ever “hype” worthy. Its really cool to know about, and should point to a brighter future, but there are always gremlins in this kind of thing. Even fuel cells, which have a deserved reputation on WAY over hyping early, helped lay the groundwork for a lot of manufacturing infrastructure and technical know how that laid the work for a lot of the battery boom we saw and continue to see.
Salt batteries are really bad, but, you know, at least they’re salt. I don’t know much about salt batteries at the expert level, but I also work on an e-chem system that is low current low density. There’s definitely applications, especially because materials and tanks are cheap, but it turns out power is stupid cheap as well.
I don’t think anyone can really predict a new “winner” right now, but it’s the biggest reason why I’m a proponent of electronification in general; we absolutely won’t be tied to Lithium forever.
Yeah I suppose thats true, I mean without a power curve the OCV isn’t all that interesting to me (and that power curve is going to be influenced by manufacturing which is probably not optimized and may or not be compatible etc etc). So like I said, neat bit of chemistry, but I do get why people get burned out on these articles.
I wonder how big it is to physically deliver (only) 1.25 V at a capacity of 110 mAh. This won’t be powering much of anything in the near term. Also I’d be curious, as they claim it being water and organic matter based, if we could just “drain” the existing battery quickly and load in new pre-charged fluid to quickly recharge (I.e. recharge an EV as quickly as a gasoline based vehicle).
if we could just “drain” the existing battery quickly and load in new pre-charged fluid
That would be huge!
For this, of course, it matters a lot how energy dense the battery is. Also for the environmental impact. If I have to exchange three gigatons of liquid for my trip to the grocery store, a rolling coal truck might have the smaller footprint.
Professor Jia said that most batteries contained hazardous materials and could pollute the environment when disposed of in landfills or when thrown out elsewhere. He said that materials like lead, cadmium, and mercury
The water powered car “disappeared” because it was never real in the first place. Every “demonstration” has turned out to be a hoax. It doesn’t even make sense in terms of physics.
Water is effectively the ash equivalent of hydrogen. If you burn carbon stuff you get ash from the impurities as well as CO2 (and some other possible things), and when you burn hydrogen you get water.
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