10 second recharge of cold NiMH batteries - Page 1
Forum section: electronics / general

author: Circlotron
author_rank: Super Contributor
timestamp: December 10, 2018, 10:41:01 am
content: This guy tells us that if you put your old NiMH batteries in the refrigerator for a short while they can then be recharged in something like 10 seconds in a *normal* charger and yet still give full capacity...https://youtu.be/f2JJH8EM9AI

author: beanflying
author_rank: Super Contributor
timestamp: December 10, 2018, 11:10:18 am
content: Wowis mild for how wrong this is. A reduction in Temperature lowers battery resistance and is like a super conductor and Liquid Nitrogen ....Currently the highest temperature super conductor is -70C under very particular circumstances. Domestic even deep freezer hit -30C at best soLowers the 'activation energy' in 30 years of charging batteriesChart shown seems to talk about photon energy and Gate voltage on one axisInternal resistance of NiMh batteries goes way up at colder temperatures which is partly why we charged at 5A+ to get them warm prior to use under heavy loads. Below zero I nearly splattered $2k of plane due to low battery under load in the early days of their use. We learned the hard way.Condensation in a Freezer by definition is an Oxy Moron water is way below the point of being a solid. Doesn't mean you won't get condensation as they warm again but the reverse is BS any water on the battery will freeze in or out of a bag.Wow after 10 seconds they have a higher surface charge than before it for just how long and how much capacity went in. 2000mAh in 10 seconds is only about 700A. This is a truck load ofThe thing I want to know is how this Muppet scammed 2 Million subs

author: ogden
author_rank: Super Contributor
timestamp: December 10, 2018, 11:17:34 am
content: Quote from: Circlotron on December 10, 2018, 10:41:01 amBS indeed. Chemical reactions slow down in cold. You shall NEVER charge cold batteries. Speaking of cold - if you know that batteries will become frozen, better use AA alkaline (or Li-SoCl2 + sleeve) rather than NiMH.

author: CJay
author_rank: Super Contributor
timestamp: December 11, 2018, 10:55:23 am
content: Just musing, please critique and correct if wrong but my thought process is making me wonder...Low temperature reduces battery/cell capacityResult, you chill or freeze a battery and a smart charger will be able to fully charge the lower capacity *much* faster?(Or it's just another bullshit clickbait video with some dubious trickery happening)

author: MK14
author_rank: Super Contributor
timestamp: December 11, 2018, 11:27:33 am
content: [EDIT: This post was badly constructed by me. It is partly better explained in later posts I make.][Feel free to dislike the way that youtuber does videos.]No No.I think you are (all) misunderstanding.He is one of the GOOD guys!He has kindly made a lot of "Public Education Videos", in an attempt to train up the general pblic, to NOT be fooled by crazy scam videos, with ridiculous claims.He also, sometimes tries to make them funny.https://youtube.fandom.com/wiki/ThioJoeI can't find the original source. So from memory (he explained what and why he does this, in one of his videos, I saw years ago, can't remember which one) ...He explains, that he got fed up with all the scammers, selling "double your internet speed" devices/techniques, etc. Hence, he use to make these videos, to try and get people to learn that ridiculous claims, are FALSE. By making these SILLY videos.Hence he use to make videos like this one:

author: ogden
author_rank: Super Contributor
timestamp: December 11, 2018, 11:45:32 am
content: Quote from: CJay on December 11, 2018, 10:55:23 amFar from "fully charge", rather 1/10 - charge. By freezing you "shrink" your battery capacity *and* it's ability to take charge. You just fool yourself and charger.Quote from: MK14 on December 11, 2018, 11:27:33 amMaybe he is, yet his "battery freezing video" is dumbest battery advise EVER. Oh, ok. I see. It's prank.

author: beanflying
author_rank: Super Contributor
timestamp: December 11, 2018, 11:51:55 am
content: Clickbait BS with hidden or NO disclaimer that it is intentional BS. The BS level on youtube is already high enough without this.Not so much Ironic as Moronic and potentially dangerous to mislead people and their place their equipment at risk for a joke.

author: MK14
author_rank: Super Contributor
timestamp: December 11, 2018, 11:52:00 am
content: Just in case anyone doubts what I say.Here is one of his explanation videos, on why he does these Prank/Funny videos. It is related to another of his prank videos.

author: beanflying
author_rank: Super Contributor
timestamp: December 11, 2018, 11:56:05 am
content: And among his back catalogue of videos chances of that one popping up first in your feed ZERO.Here is the disclaimer btwhttps://www.youtube.com/user/ThioJoe/aboutPersonally he should go back and amend his descriptions or change their category to humor.

author: MK14
author_rank: Super Contributor
timestamp: December 11, 2018, 12:01:11 pm
content: I think my original post in this thread, is a bit misleading.What I should have said is, you are fine to have your own opinion, on if this is the right or wrong/unsafe way of doing things, etc.I am just trying to point out, that he is at least claiming, that he is doing it for "good" reasons, to educate people.If in practice his videos are a good idea or not, is another matter, entirely.tl;drThey are intentionally PRANK (funny) videos.

author: MK14
author_rank: Super Contributor
timestamp: December 11, 2018, 12:06:24 pm
content: Quote from: beanflying on December 11, 2018, 11:56:05 amThat is intentional.He is trying to get some of the people, who unfortunately get taken in (believe) such videos. In the hope that they will learn from the experience and NOT fall for such videos/scams in the future.

author: beanflying
author_rank: Super Contributor
timestamp: December 11, 2018, 12:14:53 pm
content: I had a bit of a look back at some of his video titles some would certainly have the potential in the wrong hands to screw up computers for a start and I can't be bothered watching any quantity of them.Sorry but that's not funny.

author: MK14
author_rank: Super Contributor
timestamp: December 11, 2018, 12:18:44 pm
content: Quote from: beanflying on December 11, 2018, 12:14:53 pmI to quite an extent agree with you.His way of doing videos, I agree, is very controversial, and many won't agree with it.But, I think he means well. He is trying to educate people, who get easily fooled by some of these crazy/scam videos on youtube. They are also meant to be funny.EDIT: It is a balancing act. He is trying to especially reach out to audience members, who genuinely believe that "You can turn an old PS3 into a Xbox One, for free, in only 2 minutes", and stuff like that.He believes this is one way of reaching out to such people and hopefully re-educating them (mending their ways).

author: hayatepilot
author_rank: Frequent Contributor
timestamp: December 11, 2018, 02:29:24 pm
content: Thio Joe doesn't do the fake tutorials anymore.The last one he did was "Quadruple your internet speed for free" over 2 years ago.It is a serious tech channel now.

author: Wan Huang Luo
author_rank: Regular Contributor
timestamp: December 11, 2018, 03:02:36 pm
content: I can't stand the narcissism of these young YouTube hacks who put pictures of themselves in the thumbnail. Utter narcissistic trash.

author: Kilrah
author_rank: Unknown
timestamp: December 11, 2018, 03:17:00 pm
content: Quote from: Wan Huang Luo on December 11, 2018, 03:02:36 pmThey don't do it becasue they're narcissistic, they do it becasue youtube makes them do it (yes, it sucks - you could say youtube pushes people to become narcissistic?)I follow a few channels who aren't that way at all but have had to start doing it and made videos explaining that was because youtube algorithms now shoot your content down the "forgotten" pile if there's no face in the thumbnail.Aka there's a very noticeable ranking improvement for videos with faces in thumbnails, so now everybody "has to" do it if they want correct exposure.

author: Wan Huang Luo
author_rank: Regular Contributor
timestamp: December 11, 2018, 04:09:33 pm
content: Quote from: Kilrah on December 11, 2018, 03:17:00 pmShameful. YouTube enforcing clickbait. The platform jumped the shark.

author: Kilrah
author_rank: Unknown
timestamp: December 11, 2018, 05:03:51 pm
content: Nothing new.

author: IanB
author_rank: Super Contributor
timestamp: December 11, 2018, 05:30:32 pm
content: Quote from: CJay on December 11, 2018, 10:55:23 amAs thoroughly discussed in this thread, this is a bullshit video.However, to your question:Temperature has very little effect on battery capacity. The capacity is primarily determined by the quantity of materials in the battery (for higher capacity, batteries get bigger).What temperature does affect is the rate of charge or discharge of a battery. Warmer batteries work better than colder batteries. With NiMH in particular, cold is bad. If you try to fast charge a cold NiMH battery it will tend not to accept the charging current, it will have a tendency to generate gas internally, and may be damaged.

author: ogden
author_rank: Super Contributor
timestamp: December 11, 2018, 06:07:23 pm
content: Quote from: IanB on December 11, 2018, 05:30:32 pmI would not consider 50% capacity loss at -20oC as "little effect" (consumer grade NIMH AA). Usually NIMH are not even specified for operating temperatures below 0oC, that's why number is not widely known.QuoteRight. Max 0.3C discharge rate and no charge at freezing temperatures.https://batteryuniversity.com/learn/article/charging_at_high_and_low_temperatures

author: Kilrah
author_rank: Unknown
timestamp: December 11, 2018, 07:26:41 pm
content: He's just being nitpicky and suggesting it's not a "loss of capacity", it's a "rise in internal resistance that doesn't allow you to leverage said capacity until warmed up again".

author: Halcyon
author_rank: Unknown
timestamp: December 11, 2018, 07:48:50 pm
content: Quote from: Wan Huang Luo on December 11, 2018, 03:02:36 pmWhy would you talk about Dave like that?

author: Wan Huang Luo
author_rank: Regular Contributor
timestamp: December 11, 2018, 07:58:06 pm
content: Quote from: Halcyon on December 11, 2018, 07:48:50 pmHa-ha. Nice trap. Dave specifically excluded. I wanted to word what I said originally in a manner that excluded EEVBlog implicitly. Dave's doing what he needs to probably for the algorithm. The youngsters flexing for the thumbnail are the kind of folks who admire themselves in the mirror and take selfies constantly.

author: Halcyon
author_rank: Unknown
timestamp: December 11, 2018, 09:15:39 pm
content: Quote from: Wan Huang Luo on December 11, 2018, 07:58:06 pmI know what you meant. I was just taking the piss.

author: IanB
author_rank: Super Contributor
timestamp: December 11, 2018, 09:34:58 pm
content: Quote from: ogden on December 11, 2018, 06:07:23 pmHere's an experiment for you:Fully charge a consumer grade NiMH at room temperature. Now place it in a freezer and freeze it down to -20°C for a while. After that, bring it back up to room temperature and discharge it. What do you think will be the remaining charge in the battery as measured by the discharge? Will it be 50% less than nominal, or will it be more or less the expected full charge?

author: MrMobodies
author_rank: Super Contributor
timestamp: December 11, 2018, 09:45:45 pm
content: They might appear charged.He should have used a proper charger, like a SkyRC MC 3000 and apply the same charging parameters as that Energizer 15 minute charger, that would have displayed the current going into them and discharge them and then do the comparison between hot and cold. That would have been interesting.On a charger like that in the video you can't just make assumptions because they reach a certain voltage in a shorter amount of time or if the lights change that is fully charged.It sounds misleading.

author: Kilrah
author_rank: Unknown
timestamp: December 11, 2018, 09:46:36 pm
content: You missed the whole point didn't you?

author: ogden
author_rank: Super Contributor
timestamp: December 12, 2018, 12:54:16 am
content: Quote from: IanB on December 11, 2018, 09:34:58 pmPretty close to nominal obviously. Most likely meaning was lost in translation - I am not native speaker. I did mean -50% capacity lossAT-20oC - when you discharge frozen battery you get only 50% of the nominal "room temperature energy" out of it. After all we are talking about battery charging at frozen state right?

author: IanB
author_rank: Super Contributor
timestamp: December 12, 2018, 01:12:22 am
content: Quote from: ogden on December 12, 2018, 12:54:16 amYes, sure, but I do not have evidence or sources to accept your statement about capacity loss. If we stipulate that none of the internal chemicals are permitted to freeze or solidify (for example, by crystallization), then I assert that the capacity of the battery during charging and discharging will not be strongly affected by temperature. This includes when charging or discharging at low temperatures. The limitation will mainly be on the rate at which charging or discharging can proceed, and the time that must be allowed for this.My thought experiment was designed to convince you that this is the case. If it wasn't the case the frozen battery would lose some of its charge during the freezing/thawing process.

author: ogden
author_rank: Super Contributor
timestamp: December 12, 2018, 02:14:40 am
content: Quote from: IanB on December 12, 2018, 01:12:22 amCan't find original source I was referring to, but this is close. 3C rate: 50% @0oC, 1C rate: 60% @-20oC.Page #9:https://www.mouser.com/pdfdocs/PanasonicBatteries_NI-MH_Handbook.pdf

author: beanflying
author_rank: Super Contributor
timestamp: December 12, 2018, 02:35:22 am
content: Discharging at lower temperatures is an issue with the effective battery impedance increasing and as a result the output voltage dropping. This drop off in output voltage tends to be the issue long before you run out of stored charge.In my case on a sub zero morning the batteries (5 x Sanyo AA Enerloops so nominal 6V) were pulling so low under load the receiver in my glider on launch was being pulled so low it went into it's failsafe mode (3.6V) and was peeling off and heading for the groundWhen released from the towline the plane flew perfectly normally until landed. I did this again and got within 5m at speed before recoverySame result after and on the ground everything was fine.Much head scratching later and some bench testing with ice and containers we reached the conclusion the failure was temperature related as our better chargers give a read out of impedance while charging.So the conclusion to this is Enerloops NiMh are crap at delivering high currents (circa 2-3A) when cold (-3-4C) but are fine at lower loads (2-300mA). I switched them out for high discharge Panasonics with a way lower impedance but at the cost of self discharge increases.

author: IanB
author_rank: Super Contributor
timestamp: December 12, 2018, 02:43:51 am
content: Quote from: ogden on December 12, 2018, 02:14:40 amYes, and this clearly shows how the limitation is on rate of charge and discharge.The graph particularly shows the effect of temperature on discharge at 1C and 3C rates. What happens is that at lower temperatures ion mobility is reduced and the internal resistance goes up. This means that the discharge reaches the 1.0 V cut-off voltage sooner as the temperature goes down. Essentially the discharge is stopped due to voltage droop before all the stored charge is extracted.It can be seen how the 1C curve is higher than the 3C curve. At 0°C we have 50% at 3C and 95% at 1C. It's not shown, but if we had the discharge curve at 0.1C it would be higher still, and would probably approach 95% at -20°C.What graphs like this show is the difference between actual capacity and usable capacity. If you try to have a high discharge rate at low temperatures you get a much lower usable capacity. But the actual capacity of the battery has not changed, it just becomes harder to access.

author: IanB
author_rank: Super Contributor
timestamp: December 12, 2018, 02:47:53 am
content: Quote from: beanflying on December 12, 2018, 02:35:22 amA much cheaper solution is to keep your eneloops in your pocket on the way to the airfield and only put them in the glider just before use. Also wrap the battery pack in insulation like expanded polystyrene inside the glider.A good trick where the batteries are actually powering a propeller is to warm them up in a hand warmer before use to make them nice and toasty. That will dramatically increase their power output.

author: beanflying
author_rank: Super Contributor
timestamp: December 12, 2018, 03:00:24 am
content: Removing batteries in the nose of my competition gliders that is easier said than done it goes nose weight, battery, receiver, servos with nothing extra betweenThe reason for this is to minimize nose weight and hence overall weight.There is also about zero room to wrap batteries in anything due to being minmal cross sectional area for low drag and they tend to sit close to the ground for an hour plus between rounds with little time between your team mates last flight and yours.So dumping the enerloops was the best alternate in this case. The Panasonics cells btw we have used elsewhere at 15-20A so plenty up their sleeve.

author: BrianHG
author_rank: Super Contributor
timestamp: December 12, 2018, 07:42:05 am
content: If I was in my younger days, I would comment on his videos 'Great Success' stories for each one. Thanking him...Just to see the responses...

author: beanflying
author_rank: Super Contributor
timestamp: December 12, 2018, 09:04:49 am
content: Agreed to much bother to watch and troll, he has what he wanted 2 million subs but it is interesting to see how few views he gets as a percentage seems to average 30-60k so even his subs don't watch himThis is how you load test a NiMh battery btw. 100-120kg monofiliment line pushed to breaking point, 6-8 seconds for 300m traveled on tow to the release point glider transition to vertical at about 120-180 km/hr. Not your average balsa and dope glider.https://youtu.be/2WPfNt1AdBc

author: ogden
author_rank: Super Contributor
timestamp: December 12, 2018, 10:42:39 am
content: Quote from: IanB on December 12, 2018, 02:43:51 amThis graph is for Panasonicindustrialbatteries, very good NIMH's specified for freezing temperatures. Most consumer grade batteries are much worse, some hilariously pathetic.  Modern Panasonic Eneloops have good low-temp performance as well, other "low self discharge" batteries may be good as well. I know at least one another brand (can't say, sorry) that is as good as Eneloop.QuoteYes. This is how you see frozen electrolyte and slow chem reactions at work. Mentioned Panasonic was showing ~80% at average 0.2C or so.Quote from: beanflying on December 12, 2018, 03:00:24 amWhat did you change to? Li-Po?

author: In Vacuo Veritas
author_rank: Frequent Contributor
timestamp: December 12, 2018, 03:18:01 pm
content: Quote from: Wan Huang Luo on December 11, 2018, 03:02:36 pmYes, good thing we can all come hereto discuss these things....

author: MrMobodies
author_rank: Super Contributor
timestamp: December 12, 2018, 03:26:56 pm
content: I like thatQuote from: In Vacuo Veritas on December 12, 2018, 03:18:01 pmHere's a joke:I like that hand.It puts a stop to all the nonsense.The hand says stop!The face says no!

author: Buriedcode
author_rank: Super Contributor
timestamp: December 28, 2018, 07:48:59 pm
content: I think this thread goes to show, we're all prone to being fooled - regardless of how intelligent/educated someone is, if you think you' can't be fooled, then you're more prone to it. This guy has been going a while and has some great videos - and used to fool many-a-tech-journalist (who aren't exactly the smartest of the bunch). Good to see data on batteries, but.. really? I wonder how many of you lot "ate the onion" too ?It is clearly a joke, with no malicious trolling - although I did read that several people have microwaved their iphones, wrapped routers in foil, and broken DVD's to get faster internet because of this chap. The world is full of, what many would consider stupid/laughable ideas about tech/science, but this guy is the least of our problems.