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- čas přidán 21. 08. 2024
- Dave shows you an interesting ionic resistance phenomenon that lets you increase the battery capacity in typical Alkaline AA and AAA cells.
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Very interesting video!
This is a well-known occurrence in batteries with solid particles.
Alkaline batteries (and a great many other batteries) are made with electrodes consisting of powdered zinc for one and powdered carbon and manganese dioxide for the other. Now ideally when you pack them into the battery all the particles in the same electrode will touch and eventually give you a conducting path from every particle to their respective current collector component, a carbon rod or a metal can. BUT, in practice some of the particles will remain suspended in the electrolyte and not conduct. These orphan particles can't be oxidized/reduced in the electrochemical reactions and thus essentially remain unused. Additionally, during discharge, loosely connected structures of particles will disconnect as the weakest particles get oxidized/reduced first and no longer conduct the current of its neighboring particles. So more orphan particles are created. Eventually all the connected particles are discharged and the battery is dead. But these orphan particles remain.
Compressing, striking, grinding, or even sonicating the battery will dislodge the orphan particles and cause them to connect, forming a low-current path to their respective current collectors and giving some extra capacity. This capacity was always in the battery, it was just unavailable. Continued mechanical action will eventually dislodge all available particles and the battery will truly be dead.
This effect is an active area of battery research as it has implications for the life cycles of rechargeable batteries. When a battery is discharged and recharged the particles don't quite recrystallize exactly the same way as in the previous cycle and this leads to increased ESR, physical wear of the membranes and components and other problems that contribute to limited numbers of charge/discharge cycles.
Ways to reduce the effect include better manufacturing methods, additives that make the particles stick together better and prevent the weakest particles from disconnecting, as well as advanced charging/discharge circuitry that presents a pulsating load of a special waveform to the battery that discharges the particles more evenly rather than going after the weakest ones first.
Batteries with molten electrodes, fuel cells, all-liquid electrodes and similar chemistries don't exhibit this particular effect.
+NurdRage WHAT? you watch EEVBlog? maybe colab with EEVBLOG? H2SO5 vs. Fluke 78? (and other chemicals)or some LN2 stuff?
+NurdRage And? I must know!
yaaaay the Nurd squad maybe you could join Dave in his new giant lab and set up your chem lab in there .
+NurdRage Yaaaay the Nurd squad maybe you could join Dave in his new giant lab in australia.
Even though commonsense and normal, it's still cool to see all you guys interact and watch eachothers' stuff. Science & youtube 4 ever!
Batterizer better not see this video, they'll kickstart a battery squisher.
+Mickice All they need to do is make their batterizers slightly smaller and they may actually do something!
+Robee Shepherd Like turn them into mini C-Clamps?
It seems natural that when you squeeze the plates together harder, more juice will come out.
"I have no idea how much to squeeze it by." Yeah, that's what she said.
Sorry... I'll get my coat.
Didn't work with a car battery. After several hours of jumping up and down on it, all I have is battery acid all over the garage floor.
+Dave Curran That's why you need a batteriser.
+edwardecl well, I tried jumping up and down on the batteriser and all I got was a sense of happiness.
+Dave Curran that's already enough:)
You mean sulfuric acid.
Clive's vice of truth
BigClive*
bigclivedotcom
hail bigclive
+iN00bT00ber I really don't want to think about BigClive's vices
every kid from the 80/90's with a tv remote knows this squeeze trick, cept you do it on the sides instead of each end, and usually with your teeth lol
When I read " interesting ionic resistance phenomenon " I checked the date and thought you wont fool me! But this is something I used to do years ago when batteries were less plentiful and more expensive. New batteries would be used in a high current draw torch. When the torch got dim they would be transferred to a transistor headphone radio for another few hours of use. When this failed the batteries would be removed and squeezed "laterally" and put back in the radio for another 20 minutes of listening. The other trick that we used to do was put the batteries on a radiator or by the fire to heat them up. Once they were toastie you could get a bit more juice out of them. Definitely worked in the good aul days. SO now I don't know if this is an double bluff type of Aprils fool or not, especially since the other "New Office" video seemed a more obvious type of foolery!
TL:DR This video I believe, The new office one I call Shens!
Fuck's sake Dave, did you have to release this on April 1st? Now everybody thinks it's a bloody April fool's joke.
+hellterminator He also released an April Fools video on the same day.
I reckon you could get double the capacity if you throw the now squeezed battery into a turbo encabulator for a few minutes but I haven't got one on hand so I can't test.
+MrT1melord They are pretty rare I've heard.
+EEVblog The newer model Retro-Encabulator might be a little easier to find I hear.
+MrT1melord u funy
+MrT1melord If you stick it up u'r ass you'll turn into an energizer bunny
+EEVblog Will we see the turbo encabulator on TearsDown Tuesday once please?
I've heard of similar results from baking the batteries in the oven for a while. People have been known to "recharge" non-rechargeable cells thinking that they are adding power to the battery but all they are really doing is heating up the cell due to the internal resistance.
My guess is that since the cathode of an alkaline electrochemical cell is a solid (manganese dioxide mixed with a liquid electrolyte) , the products that result from the chemical reaction that occurs during discharge will stay in place after they form resulting in an area of higher resistance. Squeezing or heating the cell causes these products to become agitated (or perhaps even dissolved in the case of heating), moving them out of the way, effectively eliminating or reducing that area of high resistance and allowing current to flow more easily.
Edit: This most likely occurs on both the inner surface of the battery can (at the cathode) _and_ at the rod going up the middle of the battery (at the anode) where it exchanges ions with a zinc-containing paste or gel. The products that form are manganese(III) oxide (Mn2O3) at the cathode and zinc oxide (ZnO) at the anode. These grow inward as needle-like structures from the outer can into the manganese dioxide/potassium hydroxide mixture at the cathode and outwards from the center rod into the zinc metal/potassium hydroxide solution at the anode. Mn2O3 and ZnO are both non-conducting and basically these two will products build up until the point where they are blocking so much of the surface of the conductors that electrons can no longer get through to initiate the reactions with the manganese dioxide and zinc metal. The needle-like structures are very brittle and fragile so a little bit movement from the squeeze will cause them to break off from the surface of the conductors and migrate into the slurry around them, allowing electron flow to resume and further chemical reactions to take place.
Hope that makes sense.
It would be interesting to put isolated metal plates in the vise with the 4 terminal measurement and give it a squeeze during the discharge to see how much you can spike the output.
so AVE was right all along? keeping something in the vice makes it better?
+DUKE NUKEM
That's it keep your batteries in a vice. ;)
+kolby4078 Nice :)
he's been dispensing sagely advice all these years and we were blind to the wisdom. Why am I not surprised Duke Nukem watches AvE
Get your Vice patented right away and call it: BatterVicer! :-)
+Elnufo Vicerizer!
Nailed it
+Elnufo And market a pair of pliers as the Portable BatteryVicer :D
+Elnufo Quite or you'll give them actual ideas :P
You'll have to repeat these experiments when it's not 01-Apr.
Having said that, I had a used up (wouldn't hold much of a charge) LiPoly cell (battery?) that I extracted from a Palm T|X, and I was connecting a 50 ohm resistor across it to discharge whatever was left in it, so it wouldn't short out in the recycling bin and cause a problem such as a fire. I had a multimeter on it so I could monitor the voltage. Eventually I had to bypass the overcharge/overdischarge circuit board, but I did notice while monitoring the voltage that if I pressed on it, the voltage would rise temporarily. I attributed that to moving around the reactants, mostly the electrolyte, so that more molecules would react to produce electricity...sort of like agitating it. So to me anyway, it's not super surprising that changing the geometry slightly will change the discharge characteristics.
Yeah we used to do it back in 1880's, when we had no power in my small village in Morocco to power on the stereo. I used to hammer the top of the batteries like you did here Dave, some other people hammer the battery in all sides, some other people even boil them in water for few minutes..... Brings back memories
I foresee a "Batteriser Vice" being released in the next few months.
what's gonna be next, Sydney Opera house gonna be your basement???
+m abraham
Nice one.
+m abraham Every one knows that Australia is renting cheap since no one listen to opera anymore
+m abraham next video : how to smoke a weed (420% legit)
Not sure if two april fools videos or he really got that building...
When i was kid I had cassette walkman player. I used to chew depleted battery's to get extra hour of playback :)
Keep your stick in the vice!
+Stefan Gotteswinter AVE haha
Very interesting. I'd suggest also trying some sideways pressure to see if that also happens
I have used this trick for ages. Works great on tv remotes.
*checks date *
goddamnit, Dave...
+Falcrist Nope, April 2 in Australia. He can't have two days worth.
+John Ridley "Published on Apr 1, 2016"
+Daniel Wiggins +16 hours.... do the math?
+Falcrist I didn't even think of April fools, but the possibility exists it's not a joke. Batteries are sensitive to the resistance of their connections and even without squeezing them, if you just lightly scrape the ends with steel wool and clean the battery contacts in the device, the batteries will last longer especially in low drain devices like a television remote control. When my remote batteries die, I just open the battery door and give them a spin to scratch up the oxidized metal and they will work a few more weeks or months like that.
I think what is happening is you disturb the mostly depleted layer of electrode material and allow fresh material to be in contact with current collector rod and/or separator. See how alkaline battery is constructed.
+Lukáš Andrysík Indeed, this is the most likely explanation.
+Gameboygenius Yep, sounds plausible.
+EEVblog it would be interesting to squeze the battery during discharge and see if the voltage rises.
Wikipedia has an interesting article about REDOX a term for chemical reactions. Something has Oxidised just like Oxygen Oxidising Iron into rust. And by removing that Oxidised layer or push throughout it good contact is established again. The Zinc Carbon battery does 'eat' the outer layer of the battery but I think Alkaline doesn't really 'eat' its outer metal layer. Note, Oxidising is not something which needs Oxygen but just a term. See Wikipedia for REDOX. Like a rusty metal surface no longer a good conducter after removal of rust (Oxidised layer) will conduct much better again.
+Lukáš Andrysík What I want to know if Dave can repeat this experiment tomorrow and still get the same results ;)
i thought it was april fools video judging by the title and the date.... lol
Hi Dave, what would happen if you squeeze the fresh battery?
+Cristian Conrads Same thing I guess, but haven't tried it.
+EEVblog Or possibly developing a mechanism that would continuously apply force to the battery to ensure fresh material contacts the current collector (but that would consume energy as well)
+Cristian Conrads Donald Trump appears before you
Dennis Cat God forbid
+Cristian Conrads
Electrons would fall out of the battery.
This is known thing to squeeze battery transversely with pliers in several places and remote control will work some more
When I was growing up, if our Walman AA batteries died, we'd whack the batteries and dent them from sides -this gave more juice for like half hour(?).
Handheld Tetris lasted longer on the smashed batteries :) Some people actually chewed on them
Back when I was little, when we went camping and the D cells in our portable tape recorder died, we used to bang them against hard surfaces (or other D cells) until the sides formed visible and hefty dents. That did squeeze a few more minutes of playback out of them. Go figure. That was like thirty years ago.
+Ast A. Moore There is nothing new under the sun :)
This is useful information for those workers who listen to their MP3 players while gathering the spaghetti tree harvest.
The phenomenon that you are observing is due to the battery being under stress and hence, in pain. The increased performance is due to alkali-adrenal compounds causing momentary extra conductivity in the electrolyte, as the battery screams in the ultrasonic range. Only cats can detect this and that is why they stay away from cheap toys. Your battery will last longer if you wrap it in soft, comfortable foam and play Barry Manilow albums to it.
Hmm... The metal can of the battery would absorb most of the force from the vice so very little of it would be transferred to the electrolyte paste, and it's a paste so squeezing it doesn't change it's structure much.
What I think is happening is this forces a tighter connection and better contact between the cathode and the button top. This would cut down the resistance of the battery and lessen the voltage drop, which is what you observed. I think if you measure the internal resistance of the squeezed battery, you will find it lower.
Great advice! I stomped on my battery then installed in in place of one of the main fuses in the circuit breaker of my house. Now I'm getting free electricity off the grid! The utility company is pretty upset but theres not much they can do. I went out to the street with some hedge clips and cut the power line going to my house. Totally unneeded now! The utility company must have been watching me because as soon as I cut those wires they retaliated by shutting off the power to every house on the block! What jerks. Thats fine. I'll tell my neighbors about this free power solution later tonight.
Another battery tip for those who are interested. Batteries have a lot of energy inside of them. I found that when you've got the water kettle on the stove for morning tea, drop in a couple of AA batteries. The internal energy gets absorbed into the water so you're tea will have a little extra kick! Make sure before you drink it to remove the battery shell. Theres other harmful chemicals inside the battery that you DO NOT want to ingest. With this tip Im saving money too! I only use one bag of tea in the morning instead of two and the battery battery seems to last for about a month of daily usage. So much good information out there if you just know where to look.
Yeah man! I got a small lead acid and used a double copper helix winded DC transformer I got from ebay (make sure you get the type with the chrome core, its is 20x better at channeling the magnetism than the cheap iron core which will drain your battery in weeks) and ran my fridge on it for a year! just wacked it in place of my regular car battery, charged it up and its still rockin my fridge!
So i guess this means that Dave really did take on that massive Altium building after all? Shocker!
+100SteveB Yesterday, when viewing the video i has thinking what would happen if today there was a crazy video that looked a lot more like a april fools day joke
Brings back memory from the 90's. For every walkman-remote-boombox-RC car-or any other battery operated device.. you just squeeze them a bit (on the sides, with the teeth for AAA and AA or just bang them together on the sides for the D cells for a boombox all battery's were mashed several times and those were not even alkaline but cheap mercury based batteries.. idk the correct chemistry, but the "heavy-duty" ones)
I can't wait for Dave's Battersqueezer Kickstarter campaign!
Great info. Excellent video!
+electronicsNmore I think it was a fake video (april 1st n' all.)
Power Max Appeared realistic and logical.
+electronicsNmore Dave does make the fake video's, but luckily I think it was his last video, meaning I might be able to get free energy from squeezing batteries!
Nice video, Dave! My father and grandpa always tapped the batteries in the remote, when they were low. :-) I enjoyed very much to see real engineering approach to this phenomena. Waiting for the follow up. :-)
I don't know how you made this video with a straight face ;)
We used to deform "AA" and "AAA" many years ago in the school to get more battery life from kaset and then later CD players.
totally thought he was gonna pull an april fools joke and show off the batterizer XD
+Ben Tzion Zuckier That'll have to wait until 2020 at earliest. They might deliver then.
By squeezing a battery you shorten the flux path length. This is why ionic resistance lowers and you can get additional charge out of a battery.
This is why there is always a small spring at the end of a battery holder.
I heard rumors Batteriser just invented a squeeziniser coming soon to market.
I just use the batterizer. It works great, and some Batteroos as well. They help me economize my battery usage by spending my battery budget on them, and not having money to spend on actual batteries. It really helps cut down on the number of batteries I buy.
hahaha, Dave, never lose your sense of humor
Dave, I hope this is not April fool's joke.
If it is not, then I would suggest to make more than two cycles of all the batteries. I think 5 will be a good number (as 3 cycles are shown in data sheet, every having 1/2 the capacity of the previous one).
Hmmm not sure if April fools or sound scientific findings....I've seen's some crap april fools this year and thought I'd got off lightly this year. Then Dave comes along and throws in this curve ball. I'm off in the shed in the morning to test this!
Dave, 2 AA batteries that were squeezeв by teeth gave about an hour or two of additional working time in my walkman many many year ago when I was a kid =)
I used to do this in the 90s, we were getting crappy 777 marked batteries that were sitting for year in warehouse (poor east EU country), I would squeeze it with pliers on the sides, they ended up looking crappy but they did offer a lot more capacity, what I heard at the time is that there is some hardened (compacted) chemicals on the sides and by mashing them you would be loosening them and they would participate in the actual chemical reaction.
The EEVBlog Squeezerizer!!!! Best video for the 1st of April.
Its basically the same thing that happens when you make a homemade capacotor. The closer the plates are to eachother internally, the higher the capacitance. Essentially what your doing here when squeezing the battery is preasing the anode and cathode closer to eachother.
The reason for this is that the speed of the Chemic Reaction and so the flow of electrons will approach 0 when a certain balance between products and educts is reached (the battery seems empty). When you look at the reaction thats Happening, you'll see that (very simplyfied) 4mol of Educts react to 3 mol of Products. The Law of Le chatelier says that a reaction will always tend to the site with less force and since we're going from 4 mols to 3 mols and you increase the preasure while you're squeezing it, the reaction will tend to build more products which means more current flow.
I heard that Solar Roadways found a way to squeeze out some extra voltage today too.
On applying pressure from end-to-end, the cylindrical core with its core layered windings separate enough to move static chemistry that then is exposed to the anode and the cathode. In short, the squeezing is acting like a pump which then irrigates relatively active chemistry to the poles. The vice squeezing may be shearing off the old chemistry from the plates, where vibrating would not shear like a squeeze. I think vibrating over X_time would move more chemistry.
An alternative process is to move the internal chemistry then recharge.
Had you uploaded this in any other month, I'd probably believe it Dave :-)
What a discovery ! I knew about this since I was a little kid :)
"[...] That you can actually increase the capacity, by squeezing them in a vice"
*Me raising my left eyebrows... suspiciously checks upload date... Yes. Seems correct* 😂👌
I thought this was pretty common knowledge: Pressure and small shocks basically shakes down the chemical layers freeing more ions that otherwise can't react because they're accidentally insulated by inert material and reducing the internal resistance of the battery. That's why the battery squeezes out more aH out and the voltage drop is less sudden. I've found it's best to use a repeated taps with a rubber mallet on a concrete surface, for about 5mn per battery.
I have now tried this with 65 different batteries from various manufacturers getting on avarage 112 to 114 more mAh out of the squeezed ones. I applied between 105 and 108 N of force to the squeezed ones and had 49 batteries for control.
Wow, Duracell got their production process quite under control. 12 seconds within each other for the discharge.
I can't take anything seriously today....
Very good dave, now if I use this together with my Batterizer I bet they will last for ages to come!
No more having to buy car batteries only to dismantle them to get the precious 1.5V AAAs inside
If you squeeze flux capacitors you get extra time, useful for when you are outatime.
Maybe when a battery discharges, the internal contacts don't touch as much? Compressing it like that would force contact I think.
If you squeeze it a little more, you'll get some electrolyte juice, which is really great for hangovers. It also prevents aging, cures headaches and phimosis. Electrolyte juice mixed with some pineapple juice is a good source of vitamin C.
WARNING! ⚠
Please, for anyone reading this unironically, YOU WILL DIE! You 100% destroy with your mouth, tongue, esophagus, stomach and the rest of your digestive system, and probably get brain damage because your blood pH be so fucked your doctors will wonder how the fuck you might still be alive.
@@Lucas_Simoni what kind of people watch this channel and is unable to understand sarcasm? C'mon!!! Electrolyte juice isn't even a real thing!
Hi Dave
A few months ago
My physics professor. Mentioned it. He taught us that if the battery runs out
Throw it hard on the floor and it woke up the electrochemical action.again
battery whse not the subject so we didnt dived into that issue
I knew it was true!
We used to (gently) chew the GameBoy's batteries, in the early 90s, as kids
=)
Just clicked, trying to decide whether this is another April Fool's video or not.
10 minutes later: I first learned this from an exchange student from Mali. The batteries in a graphing calculator died and he took them out and bit them hard to get them working again. The other students and I were surprised, but it worked.
Watching this video on SnoopaVision is the shit!
+1300l Didn't you hear? The FineBros® are now suing CZcams and Snoop for copyright violation, it is now illegal to React©.
TerryMacka McKenzie
Yea but no fear as the Snoop will be the lawyer ;)
I just squeezed my iPhone in a vise and it totally worked! I was able to squeeze 20% more capacity out of it.
+Angelo Li hopefully you increased the screen's pixel density as well.
That batterizer thingy is just like 500+ in Poland...
When i was desperate to get more music out of my Walkman/Discman, i used to bite the batteries and/or bash them on the hard metal bits of the train. I didn't know this wasn't common knowledge.
I got a bucket full of used batteries , ill start smashing them and test them
Pfffffsh, every school kid from the nineties knew that! If your walkman stops playing, give dem batteries a bit of bashing and bam, it plays again, magic! Can't Explain that!
its because the battery has carbon graphite powder inside. when you pressurize it you get to well, get more Amperes from it. if you squeeze the sides also it might even make it last longer
that is true
There is obviously a good reason why a squeeze would allow a bit more capacity to be available, but has anyone tried stretching them? You can squeeze a bit more out, but you should be able to stretch more out too.
You're clearly drawing energy out of the chemo-gravitic field! It's rotated 90 degrees from the quantum vacuum and supplying more electrons by converting tachyons into electrons through chemo-gravitic action! Whoooooaaahhhhhh!
Most of these things use a 'paste' of chemicals, and whilst they do their best, probably gets impurities, like air bubbles, and other such unavoidable contaminants, so my theory is simply that you're lowering the the resistance by squishing the impurities out, whilst probably refreshing some of the electrolye paste that may have otherwise been unused up until that point.
Dammit!! I waited until the end before checking the date. Nearly got me :-)
Used to do this as a kid. Specially with remote control batteries.
The only two differences are
1- I used to squeeze them from the side, not longitudinally.
2- I used my teeth, not a vice lol.
Excellent demonstration!
The squeezed battery had a longer recovery time. That is why Dave got "more" power out of it. Over time the battery is recovering due to the chemistry. So squeezing the battery did not give the extra power. Waiting for it to recover did.
I wonder if the surfaces inside were chemically and/or physically changed from the process of discharging it, and by squeezing the cell, it caused the alignment of maybe some little pits in the surfaces to shift away from each other. Very interesting video!
Dave I've found that AA and AAA can be reinvigorated by putting them in a small plug-in to the wall battery charger. I leave them in for no longer than 30 minutes and I can use them for quite a long while. I do this with the batteries for my wireless mice and keyboards and they go at least as long as new ones. I've never measured the time by wrote but it works.
In my city this is a well known thing, when the battery runs out we put them between our teeth and deform it with a bite, or if the shell was hard we use one battery as a hammer to hit the body of the other to deform it, and it's suddenly working again .. however we squeeze the body, not the top&bottom
I used this trick long time ago. works well on dead batteries for remote control. It is handy because you can get several month of extra use. Might be useful fo wireless keyboards and mouse. For other electronics it might be not as useful because squeezed batteries will not last for any usefull time.
You dont need to squeeze them in wice. Also taping two batteries side to side, or side to hard object also works. Geting some dents on the battery bodie is what you are looking for to get the extra capacity.
For the experimet you can try to squeze thime in vice from sides.
I used to roll old carbon zinc batteries to get a bit more out of them. I thought it was my body heat but it might have been internal resistance between the carbon rod and the top metal cap. What you need is stronger springs in the battery holder. You should try it with a fresh cell on the first discharge, with bathroom scales in the vice with the battery so you can measure the squeeze force. you might need a bigger vice for that, or very small bathroom scales.
I believe you moved the center electrode just enough from the exhausted electrolyte to fresher.
Repeat giving time (24hrs) for the exhausted electrolyte to "mix" or even out. Don't squeeze.
There is a battery chemistry based on Si which has huge capacity, but enormous volume reduction when discharged.
Must be a density thing.
Like a capacitors rating is a combination of dielectric density and surface area, changing one will change the spec.
Compacting the internal compound or chemicals maybe having a similar effect.
That's my first guess anyway.
In my experience if you heat the battery up (after it was called empty), then you got also some sort of additional capacity. As i was a kid i have done this all the time for my tools.
You're putting mechanical energy into the system, like loading a spring.
I thought Wow Then I realised it's 1st April.
I don't believe anything I see today. But I like that you "squeezed" out some extra current out of it.
You got me going until drop capacity test... Ahahahahahaha... Nice one Dave :D
It must have something to do with acceleration. If you put them on a dashboard of a fast car for a while, you get a similar effect. You have to align them properly with the direction of travel for maximum effect, otherwise you're depending on the g-forces when cornering.
This only works like in the video if you squeeze longitudinally. If you squeeze laterally then the battery voltage will go up which can damage your circuit. Stay safe
you may be changing the chemical equilibrium, try repeatedly tapping it (need a mechanical device) or mechanically shaking it (maybe a bead beater or paint shaker). that may be your next product.
Once I used 2xAAA Duracell batteries for remote control for my table music player, they worked more then 10 years.)
Could be very useful in an emergency situation, I will have to keep this one in the memory bank.