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A simple way to test the charge level on alkaline batteries (2015) [video]
- gumby 3y agoHere's the paper abstract; full text behind paywall: https://pubs.rsc.org/en/content/articlelanding/2015/ta/c5ta01576f#!divAbstract https://pubs.rsc.org/en/content/articlelanding/2015/ta/c5ta0...
- system2 3y agoThanks to youtube, we are satisfied enough. These people are asking for $50 for the article. Weird.
- knolan 3y agoWelcome to the biggest scam in science. Research funded by the taxpayer, peer reviewed for free by other scientists in a journal run by volunteer editors all to be hosted as a PDF for massive profit by a ‘prestigious’ journal.
- sgregnt 3y agoWhat is the scum part here?
- xyzzy123 3y agoWell the archival and distribution costs (the only part they really do) don't seem like they should cost $50 for say a PDF file in the 10s of MBs. I think the fair value of what Elsevier (say) provide is > $0, but it's interesting to compare with say Spotify or Netflix - who actually have to pay for content.
- psychphysic 3y agoDon't forget most journals take a publication fee in the hundreds. And pay per reviewers nothing.
- xyzzy123 3y agoYep, I guess the reality is that they make all their money from "enterprise-like" sales to educational institutions. Speculating: the reason they slap a $50 charge "per paper" for non affiliated access is that they don't actually care about those sales, that's not where their revenue comes from. Essentially that is the "sucker price".
- shmde 3y agoPaying for something to access that tax payers already paid for in the first place ? How is this rocket science.
- psychphysic 3y agoCan't believe it's still an issue in 2023. The number of times I've gotten to a paywall for an mildly interesting article and I've just walked away because either the institutional access is broken, or not covered or there's simply no way to work out where the full article is.
- gorjusborg 3y agoIt's sad that people who have forgone higher financial reward and pursued a life of exploration and discovery are prevented from discussing their work unless the rent-seeking middleman gets paid. At this point, other than being the arbiters of prestige, what do the journals offer that direct peer review does not?
- olliej 3y agoOh don't forget, the journals charge a fee to submit as well. I believe a number have "open access" submission fees much higher than normal submission.
- thrdbndndn 3y agoMost (at least in my field, can't say about others) don't really charge, but yeah some do. And about open access -- some journals force you to choose open access (and hence more expensive) too.
- vbezhenar 3y agohttps://sci-hub.se/https://pubs.rsc.org/en/content/articlelanding/2015/ta/c5ta01576f https://sci-hub.se/https://pubs.rsc.org/en/content/articlela...
- dclowd9901 3y agoThis might be the first YouTube video I’ve ever actually upvoted. No bullshit, no filler, under 1 minute with all the information shared. Bravo.
- vbezhenar 3y agoReally? No bullshit? 0:20 - 0:35 is content. Rest is filled with bullshit. Worst 30 seconds in my life!
- greennsk 3y agomaxwell equations and laws of newton is the ultimate content. the rest is bullshit!
- xxs 3y agoIt's a quite known fact for long time. Still testing the voltage w/ probes (and under load) is the way to go.
- UberFly 3y agoMaybe the content is ok, but the voice sounds like it was produced with a swap-meet bullshit generator. I think I'll stick to my multimeter.
- Cthulhu_ 3y agoThere's a lot of discussion in the comments here about the format, but it's ironic because the title of the submission tells you everything already in <5 seconds depending on how fast you can read / interpret.
- jereees 3y agoWow. Glad to see that Kipkay is still making videos! The DIY laser with a DVD burner[0] must be one of the first videos I watched on YouTube. 0: https://m.youtube.com/watch?v=CgJ0EpxjZBU https://m.youtube.com/watch?v=CgJ0EpxjZBU
- winrid 3y agoIt really is neat seeing all the different phases his channel has gone through.
- dotancohen 3y agoI see that the two batteries demonstrated were from different manufacturers. I've heard this claim before, but is the difference so pronounced when using batteries from the same manufacturer? Also, the dead battery is at 0.6 volts - I've never seen a battery that dead. Is the bounce effect so pronounced when a battery is at 1.1 volts, which is a far more typical dead battery voltage?
- kalleboo 3y agoEEVBlog did the same test with matching brands and discharged to 1.2 V unloaded/0.8V loaded https://www.youtube.com/watch?v=PRf9JTg3QwA https://www.youtube.com/watch?v=PRf9JTg3QwA
- martin-adams 3y agoAn even better test would be to test the same battery before discharge and after.
- teekert 3y agoYeah that’s basic science.
- bmacho 3y agoNo that would be far far worse test than having 2 equivalent batteries, and discharging one of them. First, it is easier to measure differences than absolute values (by eye, but even with precise equipment), second it automatically cancels out the affects of temperature, humidity, pressure etc. (Okay, you know that these things doesn't matter in this experiment, still.)
- gwd 3y agoOr perhaps, buy six identical batteries, labeled 1-6; randomly charge them to two different levels (100% and 60%), three each, noting down which was which; then hand them to another set of people, who have only seen the numbers, and bounce each of them, to see how reliably they can tell the difference.
- petargyurov 3y agoMan, I remember Kipkay... I actually discovered him on Metacafe (no longer a thing). My teenage mind was blown away by how someone could know so much about electronics/gadgets so I emailed him asking what his background is. I don't quite remember his exact reply but it was something a long the lines of "I'm just a regular dude who's interested in this stuff".
- silisili 3y agoI like to hold mine between finger and thumb, and drop from low height(3/4 of an inch or so) onto a hard surface, keeping my finger and thumb nearby to catch it. A full battery will land with a thunk. An empty battery will make a fast tapping noise, like a basketball does near the end of its bounce. Same exact concept of course, just pointing out that you don't have to actually watch it bounce and fall over, you can hear it pretty easily. Helpful when testing a drawer full of suspect batteries...
- aidos 3y agoThis is an actual life pro tip! How reliable is this method?
- tomatocracy 3y agoI've been doing it this way for years, and it works pretty reliably as long as they're alkaline batteries. Since decent rechargeable AA and AAA batteries came out (Eneloop was the first), I've been replacing a lot with those though because (at least in my experience) the rechargeables seem much less prone to leaking and corroding whatever device they've been left in.
- stavros 3y agoEneloop are fantastic! IKEA carries their branded version with them, for half price, along with their high-density version. I got a bunch of IKEA rechargables and I'm sorted.
- NoZebra120vClip 3y agoJust like float-testing my eggs
- Cthulhu_ 3y agoJust what I was thinking of. Putting it on a surface and spinning it also works, a raw egg will stop fast due to sloshing, a hard-boiled egg will spin for a while.
- teekert 3y agoThe float test is for freshness. I use it a lot. But never saw a floating egg, also never had a bad one. Time for an experiment I guess.
- justsomehnguy 3y ago> also never had a bad one Consider yourself lucky. I had one, breaking them into the bowl for the scrambled eggs and one of the batch was foul. I was ~8 at that time and if my parents weren't there I would probably just run away never to get back to that kitchen, house, city.
- FabHK 3y agoYou can also quickly stop the raw egg, and it'll start turning again (unlike the hard-boiled one).
- TaylorAlexander 3y agoIt’s true a properly charged egg won’t bounce!
- Timon3 3y ago> isNaN(egg) false Seems like you're good to go!
- yieldcrv 3y agoI kind of love how the TikTok version would just show the battery dropping and a caption, and then you could move on with your life funny how this "30 second" 44 second one was supposed to be quick and engaging
- justsomehnguy 3y agoAnd both would be forgotten by the time the next video would start. Still, Vine was the epitome of 'to the deal'.
- spullara 3y agoI was talking to a founder of a battery company the other day and he said "there are two kinds of moving parts in your iphone, the buttons and the battery". The lithium literally moves from side to side as it charges and discharges.
- speedgoose 3y agoThere is also the speakers, the microphones, the lens (focus), the vibrating motors, and probably a few other things.
- bongobingo1 3y agoThe glass moves quite a lot once I drop it.
- NavinF 3y agoNot so much with modern phones; the glass has gotten a lot stronger over the years. I can drop mine on hardwood with no visible effects and dropping it on concrete only causes cosmetic issues (chipped edges) without affecting functionality. I went caseless and screenprotector-less ~10 years ago and never regretted it.
- deepserket 3y agoThe gyroscope and the accelerometer https://youtu.be/9X4frIQo7x0 https://youtu.be/9X4frIQo7x0
- hwillis 3y agoMost/all of the capacitors (which are mostly piezoelectric), the inductors, any ferrite beads, and of course thermal expansion. I'd also bet that liquid crystals change pressure when they rotate, but idk.
- Someone 3y agoSo, can we, in theory (I guess the effect will be small), measure battery charge by measuring the center of gravity and/or rotational inertia of batteries or even smartphones?
- micw 3y agoI just had the idea to analyze this using scientific methods and write a paper in my spare time (would be my fist paper ;-) ). But seems there is already one: https://www.princeton.edu/news/2015/03/30/battery-bounce-test-often-bounces-target https://www.princeton.edu/news/2015/03/30/battery-bounce-tes... Quote: "The bounce does not tell you whether the battery is dead or not, it just tells you whether the battery is fresh".
- alister 3y agoThe explanation as published in the Journal of Materials Chemistry: "As an alkaline battery is discharged, the anode undergoes oxidation from Zn to ZnO. ... The battery most likely begins to bounce because of displacement of water by solid ZnO bridges between particles of zinc in the gel. These bridges provide less impeding and attenuating paths for pressure waves, in turn making the battery bouncier." -- The relationship between coefficient of restitution and state of charge of zinc alkaline primary LR6 batteries (same paper already mentioned by others)
- eezynow 3y agoi am an audiologist. this is my go-to method for checking hearing aid batteries on the fly, especially as it lets me work a bit messily.. for better or worse, i now have a habit of ripping fresh batts out out of a packet, without immediately disposing of the old ones i have removed from an aid, while my attention is focused on programming it (older aids often interface using a cable connected to a programming 'pill' which supplies power and data through an empty battery cavity... so i can be putting batteries in and out and programming cables in an out, multiple times in a session with a client... anyhow..) i no longer need to pay attention as to which battery is which, as i just pick up both together and drop them from about a 15cm height.. the old one bounces jauntily away, while the new one stops dead with zero bounce. it is a super accurate trick and the information never fails to astound clients.. it surprised me when i learnt it from an old salt colleague and it surprises me more that it is not common knowledge.. especially amongst my workmates.
- londons_explore 3y agoHearing aids mostly use zinc-air batteries. I believe your trick works for a different reason - zinc-air batteries get heavier as they discharge since they absorb water from the air.
- eezynow 3y agothanks.. i really know nothing apart from that i enjoy doing it with hearing aid batteries myself.. there is something really satisfying watching the no-bounce battery. as for the reason, i always presumed it was because they take in oxygen. i can't find anything on the weight of discharged vs charged zinc air batteries... but they have always felt a teeny tiny bit lighter when used (i have no evidence!) and i am not sure about your water supposition... i know they -can- swell with water if it is too humid for example, but generally, don't they expel water as they discharge...? "Zn–air battery uses oxygen from the air, and hence, air holes in it are kept open for cell operation. Therefore, loss of water by evaporation through the holes is inevitable. When the water is depleted, the battery ceases to operate. There are two water consumption routes in Zn-air batteries, namely, active path (electrolysis) and passive path (evaporation and corrosion)." source: https://www.jecst.org/journal/view.php?number=300 https://www.jecst.org/journal/view.php?number=300 regardless.. here is a nice video of the effect in hearing aid batteries.. https://www.facebook.com/BMHearing/videos/2037506353043179/ https://www.facebook.com/BMHearing/videos/2037506353043179/ sorry the only link i can find worth sharing is on FB.
- Wowfunhappy 3y agoWhy are people still using alkaline batteries? I have a bunch of Enloops which I pop into everything. Mice, keyboards, game controllers, TV remotes, soap dispensers, etc etc. I also have a bunch sitting in chargers, so I can quickly swap an empty battery with a full one whenever I need to. As far as I can tell, the ones I first bought in ~2015 are still going strong. I do explicitly seek out products which take AAs as opposed to using internal rechargeable batteries, because I can swap out my Enloops in less than a minute, versus plugging the product in and waiting hours for it to finish charging!
- elliottkember 3y agoPeople see batteries as "cheap and disposable". The price tag of $15 for 4 batteries is a one-time hit that most people in the US* don't want to take. You and I both know they will save money over time, and yes, it's much better for the environment to reuse, but that is why. *I come from a non-US country, and was brought up using rechargeable batteries. I have lived here for 10 years and I have not seen a single rechargeable AA at any point.
- sgtnoodle 3y agoLast time I looked into it end-to-end, it seemed like a NiMH cell would need to be reused like 500 times in order for it to actually be an improvement for the environment over one-time-use alkaline. NiMH is better than NiCd but still relatively nasty.
- _joel 3y agoBecause I'm pretty certain most people don't even realise they exist and it's easier to grab some from the local shop when your remote dies.
- zzzeek 3y agowe have dozens and dozens of AA batteries here, like everyone else. and your suggestion "why aren't you using rechargables" is compelling, buying a ton of these and just having them in a charger seems like a good idea. So what are the little things in my mind making me hesitate? 1. how long they will continue to remain rechargable; and if they begin to hold less and less of a charge. if they are still recharging fine for you after 8 years, that seems pretty good. 2. what happens if the rechargable battery is left inside a forgotten toy or device for 7 years? if I find it 7 years later, is it a leaky mess or still viable? this is a big reason "AA's are disposable anyway, who cares" is appealing - we have forgotten batteries all the time. if we forget about a toy and our $3.50/each batteries are ruined we could be buying a lot of these pricey batteries 3. how long do they last on a full charge? if use them for camp lights are we going to run out of light after a day ?
- polishdude20 3y agoAnybody else lick their batteries?
- asadm 3y agocan you tell 1.5v? I do check 9v battery by tongue.