A simple way to test the charge level on alkaline batteries (2015) [video]

https://www.youtube.com/watch?v=nwfFBUVxpac

by gumby • 3 years ago

111 120 3 years ago

youtube.com

gumby• 3 years ago

Here's the paper abstract; full text behind paywall: https://pubs.rsc.org/en/content/articlelanding/2015/ta/c5ta0...

system2• 3 years ago

Thanks to youtube, we are satisfied enough. These people are asking for $50 for the article. Weird.

knolan• 3 years ago

Welcome 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.

vbezhenar2• 3 years ago

https://sci-hub.se/https://pubs.rsc.org/en/content/articlela...

dclowd9901• 3 years ago

This might be the first YouTube video I’ve ever actually upvoted. No bullshit, no filler, under 1 minute with all the information shared. Bravo.

vbezhenar2• 3 years ago

Really? No bullshit? 0:20 - 0:35 is content. Rest is filled with bullshit. Worst 30 seconds in my life!

greennsk• 3 years ago

maxwell equations and laws of newton is the ultimate content. the rest is bullshit!

xxs• 3 years ago

It's a quite known fact for long time. Still testing the voltage w/ probes (and under load) is the way to go.

UberFly• 3 years ago

Maybe 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_2• 3 years ago

There'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• 3 years ago

Wow. 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

winrid• 3 years ago

It really is neat seeing all the different phases his channel has gone through.

dotancohen2• 3 years ago

I 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• 3 years ago

EEVBlog did the same test with matching brands and discharged to 1.2 V unloaded/0.8V loaded https://www.youtube.com/watch?v=PRf9JTg3QwA

martin-adams• 3 years ago

An even better test would be to test the same battery before discharge and after.

rob74• 3 years ago

Well, it should be relatively easy to try to reproduce the experiment... but yes, I agree that a battery will be considered "dead" when the device it was powering stops working with the provided voltage, and 0.6 volts is likely far below that voltage (except maybe for traditional flashlights with incandescent bulbs which get dimmer and dimmer, but will probably still work?).

bentcorner• 3 years ago

I use this all the time with the bulk batteries from Costco. My gut also says the bounce effect is a little too sensitive, as I've had batteries have a good bounce even when the device they're is still able to pull some juice out.

But a fresh battery will 100% not bounce. It's the simplest thing to do when you're changing the batteries in something and you got the old/new batteries mixed up.

petargyurov• 3 years ago

Man, 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".

silisili2• 3 years ago

I 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• 3 years ago

This is an actual life pro tip! How reliable is this method?

tomatocracy• 3 years ago

I'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.

londons_explore4• 3 years ago

doesn't work with cheapo zinc-carbon batteries. You can normally tell those though because they are lighter and if you squeeze them firmly they dent.

londons_explore4• 3 years ago

Very reliable for telling brand new vs 100% depleted batteries.

But if you want to separate 1.4 volt batteries from 1.5 volt batteries, use a multimeter.

NoZebra120vClip• 3 years ago

Just like float-testing my eggs

Cthulhu_2• 3 years ago

Just 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.

teekert2• 3 years ago

The 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.

FabHK• 3 years ago

You can also quickly stop the raw egg, and it'll start turning again (unlike the hard-boiled one).

TaylorAlexander• 3 years ago

It’s true a properly charged egg won’t bounce!

Timon3• 3 years ago

    > isNaN(egg)
    false

Seems like you're good to go!

yieldcrv• 3 years ago

I 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

justsomehnguy2• 3 years ago

And both would be forgotten by the time the next video would start.

Still, Vine was the epitome of 'to the deal'.

spullara• 3 years ago

I 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• 3 years ago

There is also the speakers, the microphones, the lens (focus), the vibrating motors, and probably a few other things.

bongobingo1• 3 years ago

The glass moves quite a lot once I drop it.

deepserket• 3 years ago

The gyroscope and the accelerometer https://youtu.be/9X4frIQo7x0

hwillis4• 3 years ago

Most/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.

Someone2• 3 years ago

So, 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?

hwillis4• 3 years ago

No- the inside of a li-ion battery looks like this: https://www.researchgate.net/profile/Jigang-Zhou/publication...

Li-ion battery comes off the production line as one continuous, miles-long tape that is rolled into shape and then sliced off. The tape is made of a few layers, and li ions move from one layer to another. All of the movement cancels out.

You could measure the state of charge by mass, though! As electrons are moved from anode to cathode, they occupy a lower energy state and therefore have less mass. You'd measure that in eV, electron-volts: convert amp-hours to coulombs and you have the number of electrons, and the average voltage change is from roughly 3.7 volts to 3.2 volts. Or you could use the much easier formula- E=MC^2 :D

hwillis4• 3 years ago

Well, side-to-side as in less than 100 microns. The inside of the battery is a very long tape that is rolled up like folded paper. The tape is:

1: Aluminum foil (about 1/10th as thick as household foil)

2: Cathode material (metal oxides, like NMC or NCA)

3. Separator film (polypropylene + polyethylene, which blocks electrical short circuits but lets li ions through- only ~20 microns thick)

4. Spheroidal graphite anode (mostly artificial, some natural)

5. Copper foil

The ions (and some amount of solvent- the solvation sheath!) travel from cathode <-> anode.

micw• 3 years ago

I 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-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• 3 years ago

The 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)

eezynow2• 3 years ago

i 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_explore4• 3 years ago

Hearing 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.

eezynow2• 3 years ago

thanks.. 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

regardless.. here is a nice video of the effect in hearing aid batteries.. https://www.facebook.com/BMHearing/videos/2037506353043179/ sorry the only link i can find worth sharing is on FB.

Wowfunhappy3• 3 years ago

Why 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• 3 years ago

People 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• 3 years ago

Last 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• 3 years ago

Because 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.

zzzeek2• 3 years ago

we 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 ?

frabert• 3 years ago

For point 2, NiMH cells are _way_ less prone to leakage than alkalines. In fact, I've never seen a leaky NiMH cell (that hadn't completely vented due to severe overcharge, anyway)

Wowfunhappy3• 3 years ago

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.
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 ?

The batteries last long enough that I can't answer these questions. I will say I don't own any devices like camp lights where battery life is a significant problem. The batteries in e.g. my Apple Bluetooth Keyboard last for months.

One thing to be aware of is that the voltage curve is different than for alkaline batteries†, so devices like my keyboard will start giving low-battery warnings when they are still mostly charged. This is legitimately annoying on e.g. macOS where you can't disable the warning. Why I would ever want to replace the batteries before they're actually dead is beyond me.

† I don't really know what I'm talking about, this is the explanation I found when I looked up the problem online years ago.

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

I've been using the batteries continuously for that long and they haven't leaked. I'm not even sure these types of batteries can leak? I'd love for someone who knows more about battery chemistry to chime in here.

memco• 3 years ago

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

I had some eneloops in flashlights when we lost power for several hours—almost all the batteries died within an hour of use. I will use non-rechargeable batteries for those from now on unless the higher capacity rechargeable ones won’t drain so fast. My kitchen scale, remotes and mice have all been fine (often needing to be recharged only once every year or two) but some uses don’t seem suited to rechargeables.

Espressosaurus• 3 years ago

1. I've had batteries for 10 years before the charge was small enough I started noticing and began replacing them

2. I've had the odd leak from an unused rechargeable, but we're talking one out of 16 batteries. I've had more leaks with the unused alkaline batteries in the same long-ignored dish.

3. They last as long as their mAh rating. They're fine.

tzs4• 3 years ago

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.

My first generation AA Eneloops, which I bought sometime in 2008 or earlier (I know this because I bought them at Circuit City which closed in March 2009 and I bought them at least several months before then), are still working fine.

Their specs say minimum 1900 mAh capacity, typical 2000 mAh. Most of them have fallen to slightly below that, in the 1850-1900 mAh range.

My first generation AAA Eneloops, purchased at the same time, are all in the 790-840 mAh range. Spec is min 750 typical 800.

My 4th generation AA Eneloops, bought almost 9 years ago (their 9th anniversary is in 3 days), which I've used more heavily than the first generation ones because they have a lower self discharge (1st gen is 80% after one year, 4th gen is 90%/80%/70% after 1/3/5 years), are mostly still in the 1900-2000 range, with one at 1880 and one at 2055.

I've had 2 (out of 21) first gen AAs and 4 (out of 16) first gen AAAs die. None of my 4th gen AAs have died. By "die" I mean my PowerEx MH-C9000 charger says they fail an impedence check that it does before charging and refused to charge them, and no attempts to revive them worked.

2. what happens if the rechargable battery is left inside a forgotten toy or device for 7 years?

I don't know but someday I'll maybe find out, because I have 3 first gen AAs that I've lost track of. They are probably in something in my junk pile, like a remote for a VCR.

patricklorio• 3 years ago

I think avalanche transceivers need alkaline batteries because they work better in the cold and have a more reliable voltage drop as the energy is drained. But beyond niche applications, rechargeable all the way :).

sixothree• 3 years ago

But lipo AA exist now.

purpleflame1257• 3 years ago

One thing I have noticed is that devices with built in voltage sensors will oftentimes read even fully charged rechargeables as low battery, which can be annoying. This has happened with devices as new as a Roku remote and as old as a Game Boy Advance. It may vary from battery brand to brand, but I just use the AmazonBasics.

p0w3n3d2• 3 years ago

it's because rechargable AA is not a proper AA (standard) battery. It's an "all-what-we-could-fit-in-such-a-small-compartment" battery.

singron• 3 years ago

The common rechargeable battery chemistries are 1.2 V (NiCd, NiMH), but a normal alkaline battery is 1.5 V. It usually works OK because the alkalines drop voltage quickly and devices are designed to operate in a lower range. If you can fit it in somehow, it something makes sense to add an extra battery. E.g. 5 rechargeables has the same voltage as 4 alkalines (6V).

mattmaroon2• 3 years ago

I use plenty of rechargeable batteries, but I also use disposables. Disposable batteries hold significantly more charge and sometimes that matters.

For instance my smart lock if I fill with rechargeables I find myself having to call a locksmith. I think that might be not only due to the lower capacity but that it holds closer to voltage until completely drained so it prevents the lock from giving me adequate warning.

I also have a property that’s an AirBnB and I’m sure those tenants are animals, so I leave the disposables for things like remotes. They would just dispose of rechargeables if I let them.

cogman10• 3 years ago

Disposable batteries hold significantly more charge and sometimes that matters.

Not really true but also not wrong. Disposable batteries tend to be on par with rechargeable when it comes to charge. Disposable AA 2850mAh [1] Rechargeable 2000mAh [2]

What you are (likely) experiencing is that rechargeable batteries tend to have much higher self discharge rates than disposables. The end result is the rechargeable feel like they have less capacity as they seem to last for a shorter period of time. Further, the lower voltage tends to also push you to need to recharge them because your devices fail to work at the lower voltages.

The dastardly part of rechargeable is you can get like 3500mAh AA but you shouldn't because those tend to have absurdly high self discharge rates. (AFAIK) The enloop batteries tend to be the best when it comes to self discharge, but at the cost of lower total capacity.

[1] https://www.supplyhog.com/c/electrical/batteries-flashlights...

[2] https://www.amazon.com/Panasonic-BK-3MCCA4BA-eneloop-Pre-Cha...

kgermino• 3 years ago

I is rechargeable a for almost everything, but I have some devices which don’t tolerate the lower voltage of NiMH

p0w3n3d2• 3 years ago

eneloop battery is not a proper AA battery. Proper alkaline battery does 1.7V when charged, while eneloop does max. 1.5V (usually 1.45V and deteriorate over time). Some electronics which depend on this, will malfunction or work very shortly on rechargable eneloop or similar.

this chart https://www.prosoundweb.com/images/uploads/Fig1CTA_BatteryGr... shows max 1.6 but I witnessed 1.7 on full alkaline and 1.45V on eneloop

tzs4• 3 years ago

Some electronics which depend on this, will malfunction or work very shortly on rechargable eneloop or similar.

Take a closer look at the graph you linked to. Those devices will also stop working very shortly on alkaline batteries. The voltage as a function of discharge capacity curve for alkaline falls below Eneloop about 1/3 of the way in.

That means that if the device can work at alkaline voltage after it has used about 1/3 of the alkaline capacity it will also work as long or longer with an Eneloop of the same total capacity.

The alkaline curve voltages falls below max Eneloop voltage after about 10% discharge. That means a device that actually needs a voltage above Eneloop voltage was poorly designed. It is either going to be ridiculously wasteful on alkaline batteries (unless the user realizes that when the device conks out due to low batter the batteries actually still have 90% capacity remaining and uses those batteries in some other device designed by a competent engineer instead of throwing them out as dead) or should have been using something other than AA batteries such as CR123A that will be above 1.4 V throughout most of its discharge curve.

The only problem you should see in a well designed device that was designed for AA but for which the designers did not take into account rechargeable vs primary is that the battery indicator might not be as accurate on rechargeable. That's because simple batter indicators use the voltage to estimate where they are on discharge curve.

If this assumes an alkaline discharge curve then with a rechargeable it will think fresh batteries are at about 90%, which will rapidly fall to around 75%, and then think it is barely declining for a long time until the batteries are actually at about 10%, and then it will rapidly go down.

petee• 3 years ago

Enloops low voltage causes a few of my devices to freak out, and my guitar tuner will go into 'boot loops'. Not sure why they even sell them when they don't match the characteristics of the AA form.

I only have them for tv remotes/mice. Alkaline are also reliable for headlamps when I'm in the mountains.

jandrese• 3 years ago

I mostly agree, except for TV remotes. My experience is that the cheap off brand batteries that came with the remote will likely last for the entire lifetime of the device, a decade or more. Replacing them with rechargeables is a waste and a hassle since even Eneloops have a self discharge curve that means you have to pop the batteries out and top them off every few years.

spookthesunset• 3 years ago

It's crazy how to batteries that come with electronics seem to last forever isn't it?

copperx2• 3 years ago

Why Eneloops instead of rechargeable batteries? Is there an advantage?

ianburrell• 3 years ago

Eneloops are rechargeable batteries. They have low self-discharge which means they don't lose their charge quickly like normal NiMH batteries, and can store them charged and devices don't need to be charged frequently. There are now other similar brands but Eneloops are most popular and maybe even generic name.

alanbernstein• 3 years ago

I started making the transition, and then I realized that it makes me think of each eneloop as a device that I need to think about and maintain. How much life does it have left in it? How can I measure that? How can I remember which is which?

It's been a few years, so I couldn't tell you exactly what happened that made me think this way. But some devices worked with brand new eneloops but not as well with older ones.

Also, my camera flash dies (e.g. drops from usable to unusable) much more rapidly with eneloops. I missed a few one-of-a-kind photo ops and then decided the flash only uses alkalines now.

nuancebydefault3• 3 years ago

My reasoning is, AAA or smaller use alkaline, they start off 1.5 volts and last a very long time. (if you use nimh, they are only 1.2V). AA or higher: use nimh or li ion instead, those are generally more power hungry devices.

tzs4• 3 years ago

I think part of it is that most people probably think that the cost of the useable energy in a battery is a significant amount of the cost of the battery. And so they expect that the cost to recharge a rechargeable battery is going to be about the same cost as buying a new disposable battery (or more...the disposable battery maker will be getting their electricity at industrial rates which are usually quite a bit lower than residential rates).

And so they think that what you are paying for when you spend 6x as much to buy a rechargeable battery is mostly the convenience of not having to go the store to buy new batteries.

But since batteries are sold at the grocery store and at convenience stores and have something like a 10 year shelf life it isn't actually inconvenient to just keep a small stock on hand and replenish them as needed when buying groceries, except maybe for the exceptionally forgetful or disorganized.

In fact batteries are a very expensive way to buy energy.

Take a 2800 mAh AA alkaline battery. At a nominal 1.5 V that's 4200 mWh of energy, or 0.0042 kWh. If you live in someplace with very high residential electricity rates such as Denmark or Germany that's about $0.0023 worth of electricity.

In the US, where electricity is a bit cheaper, for the average consumer it would be about $0.0007. It would take 1400 of those batteries to get the same amount of electricity that would cost you $1 when taken from a wall socket.

The result is that for most people they will save money with rechargeable batteries. The exceptions will mostly be people who have very few devices that use AA or AAA batteries. They might go through batteries at a low enough rate that the savings each time they need to change batteries isn't enough to overcome the upfront cost of the rechargeable batteries and a charger.

eternityforest• 3 years ago

The only good reason for a disposable battery is if the power draw is somehow that a rechargeable would have expired from calendar aging by the time the disposable is dead. Very high efficiency RTCs, emergency backups never expected to be used, highly specialized devices used for only a few minutes a year, etc.

I do really think that we need a better rechargeable battery standard though. If something is big enough for it, 18650s are close to perfect, but not much is.

There's enough devices like GoPros which have swappable batteries and third-party availability, and so are de facto standards, why don't people just design their stuff to use one of those?

polishdude20• 3 years ago

Anybody else lick their batteries?

asadm• 3 years ago

can you tell 1.5v? I do check 9v battery by tongue.

A simple way to test the charge level on alkaline batteries (2015) [video]

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