EEVblog
Vložit
- čas přidán 15. 07. 2024
- How to safely charge Lithium Ion & Lithium Polymer batteries with a bench power supply, for when you don't have the correct charger available.
WARNING:
Take care using PSU's for charging unprotected cells. A fault in the PSU might overload or short the battery & that could be dangerous.
Always watch your battery during charging using a general purpose technique like this.
Forum: www.eevblog.com/forum/blog/eev...
Datasheet: www.math.ubc.ca/~wetton/paper...
Lithium Battery Charging Tutorial:
• EEVblog #176 - Lithium...
EEVblog Main Web Site: www.eevblog.com
The 2nd EEVblog Channel: / eevblog2
Support the EEVblog through Patreon!
/ eevblog
EEVblog Amazon Store (Dave gets a cut):
astore.amazon.com/eevblogstore-20
T-Shirts: teespring.com/stores/eevblog
💗 Likecoin - Coins for Likes: likecoin.pro/@eevblog/dil9/hcq3 - Věda a technologie
Says short video, keeps it a little under 14 minutes. Says he's not doing an tutorial channel and manages to be a top resource to go to. Pure gold! You can almost get 20 years worth of EE experience just by listening to Dave going into all the little minutia. You can actually get a "feel" for this stuff and feel confident enough to do build your own charging circuit just by watching this video.
them gatekeepers
Making use of the czcams.com/users/postUgkxcJ22tnHH9l1vjdIdEIG27iOG55P7LXI8 reconditioning plan, I just saved 2 auto batteries from being completely junked. The guides were very simple to follow. I wish I would have found this years ago! You may use the guide to recondition any battery type
Sorry for the re-uploads, I wanted to remove most of the the voltage drop stuff to avoid confusion and constant emails and messages and comments for the next 5 years.
What was the problem?
🖒
And i thought youtube does not like your videos anymore ;-)
+Fermioncool Fermioncool I assume the voltage drop could be seen as a extra security, at the batteries emd you will never go beyond 4.2, again I assume.
Dave, maybe this is a small video, but the topic is very popular in recent times, and every mistake can be noticed and stigmatized that it is not repeated.
I liked how you repeated certain parts of the video Dave. Like when discussing the graph. This is really really helpful for people like me who struggle to learn these ideas.
It's so simple, but I've never thought about it! Thanks)
Thank you! I spent $400 on a drone, and didn't buy a lipo charger because I thought I had one. This will get me buy until Amazon gets one to me!
Nice one again Daveo, totally trusted content. The absolute best.
I have been charging 18650 cells on my lab supply for years. Set the current to 1A and the voltage to 4.2v per cell. Stop charging once the current is reduced to 100mA. Sometimes I charge overnight with a current limit of 250mA and again stop the charge when the current reaches 100mA. I have started experimenting with TP4056 modules which automatically stop the charge which is quite handy for unattended charging.
what aliexpress supply can do this stuff?
max is 1C
Nice video. I've got a Rigol DP832, no doubt because you've shown/reviewed/talked about it here. A video showing how to use some of the advanced features would be useful to me! Many of these devices are similar....the concepts would transfer to other makes and models...
Awesome video Dave!
Cool video! Thanks Dave!
Thankyou for this simple to understand tutorial. I now understand, mystery revealed :)
Rigol actually has an app note, warning you not to hook up batteries, without at least a diode as protection, since the DP832's inputs are apparently very sensitive to being fed with voltage or current.
Thanks, I was looking for that. I was sure Dave mentioned this in a previous video. He must have forgotten.
Thanks for uploading this. This made me finally charge my Canon camera LP-E6 battery with a constant current on 650mA and when reaching the maximum voltage of 8.4v i changed over to constant voltage and see exactly the same where the current starts dropping! Wow, i really need the camera tomorrow and you made me do it! Best youtuber EU! (i know you're not in the EU)
Super Video Dave !
It's been mentioned, but military tech only charges lithium batteries to 3.9v. Maybe 80% of the capacity, but close to 5 times more charge cycles.
Yes, at a "storing" voltage... exactly right
Nice!!! this is the video i needed!!Nice explain!!😁TKS
I needed this video. It helped me thanks.
beauty! enjoyed thanks for all you do! an have a super weekend
Nice video! Thanks!!
Any chance you could do a follow up or give a base explanation of how to charge a Lithium ion pack with cells in series and parallel?
You little ripper! Love it!!
Thank you, sir!
Good explanation 👍
Also do a how to safely discharge video please, cheers !
very informative. thanks.
You could put your power supply on a cheap outlet shut-off timer if you didn't have a fancy expensive power supply.
3:20 I'm commenting on that 3.5-inch digital multimeter again.
Watch out for that first step, it's a doozy.
Thanks for the idea, 100% gunna use that one
Excellent! Thanks.
Brill. Thanks Dave.
Well done.
Keep up the good work Dave!
Tyvm for good a explanation. I don't know anything about electronics but i recently did this a couple of times with a homebuilt powersupply/lab. I only charged it for short periods tho and monitoring it while doing so but it feels a bit sketchy when not having the knowledge :D My battery was 500mah and i charged it at 0.5a tho but now i know to lower that! My voltage setting was not set by specs, more based on some quick basic values i found online that semt to correlate somewhat to the battery type. I did have in consideration that the battery could go poof while trying this.
thank god for eev. have you see some of the other videos out there....
Hey Dave, can you do a video on how to “revive” a flat lipo pack? I see other CZcams videos from others but it would be good to get your explanation on how or why this works.
Funny thing is I only recently received my DP832 bench power supply and have used it to charge a couple 18650 batteries.
Hey would you do a strip down of any "vaporizer" regulated battery modules? They generally use 18650 batteries to heat a coil which vaporises liquid. I think it's interesting from an EE perspective because these mods measure the resistance of the coil, and use some kind voltage stepper to allow you to select a wattage for powering the coil.
I did read that Lipo batteries are more dangerous to charge without a specific "balancing" charger . Then may be some balancing circuitry exists in my battery pack, not only a heat sensor and constant current constant voltage circuitry (?) I did unsold it from the batteries to be sure of what happens) thank you
Excellent video. All explained very well. Thanks!
great video
can I suggest a second video where you explain the problem of the original?
I was hoping you were going to do a bench supply charging video!!!!
I was thinking if you calculated the right resistor, you could rig a transistor in there so that once the current goes too low (the cut-off point), the transistor breaks the connection to the battery.
great vid thx
It's like you read my mind. I would also like to know the differences between charging LiFePO and this one.
That would be an interesting arduino project : LiPo smart charger.
You can do the same, with different voltages and currents for NiCd, NiMh batteries. I've been recharging 1.5V _alkaline_ cells as well with my PSU, works great (1.7V, 150mA). Doesn't work on 9V batteries, though. :(
In before the next reupload :)
Dave, that cheap PSU you reviewed the other day - the one that caught fire, would such kind suffice for charging Li-Ion or are they not accurate enough (when they're not burning that is)?
Thanks, Nice and beneficial Video, do you have a video about the rate discharge measurement of the Li ion battery?rate
Thx man
Any recommendations about charging a 7.2 Volt Li-Ion camera battery pack like a Sony NP type?
Great video and explanation!
I'm really interested in the model of the wrist watch this fine gentleman is wearing. I cannot find it on the internet...
thank you for talking about slowly rising voltage when in constant current mode but i saw something when i charge the battery with constant current mode . the voltage drop across battery was 4.2 v or around that. and voltage across the cell before charging was around 3,8 . so why is it behave like this. isnt it should be 3,8 v across the cell while charging it with constant current and slowly rise the voltage naturally like you show in the video ?
The safe max charging V for that Panasonic cell = 4.25V
The recommended charge cut-off A = 65mA (which is 0.02C, not 10% of the CC).
Thanks for sharing.
p.s.: If you want to get max cycle life out of the cell, it is recommended to charge it to a max V of 4.1V & not discharge it more than 20% when using it. >= 50% DOD really creates a significantly shortened cell life.
A B Buying a cell to discharge it no more than 20%....no thanks.
OrbitalSP2:
Well, your power needs may be quite different than someone who wants optimal cell life--which is fine--you'll just consume more cells & pay more $ for your power needs than a person seeks optimal cell life.
A B I know what you say is true. But i just avoid discharging more than 80%. I mean discharging only 20% only, I can't even see in what aplication that might be useful. 20 minutes runtime in a flashlight?
+OrbitalSP2
A flashlight that isn't used much or often is a perfect example. I have a high power flashlight that I use occasionally around the house & I rarely use it for longer than 5 minutes in a day.
A remote control that is placed on a wireless charging mat when not in use would be another good example.
A B they degrade with time, even by doing nothing with them. So I'd rather use them from 20 to 90% or 20 to 100%. Unless you live in a very very cold country, the ambient temperature is killing them anyways...
Wanna hear a joke?
Batteriser.
Lab power supplies aren't the same as batteries. Batteriser proved it!
FUCK OFF! .... in a ten minute video they CONTRDICTED THEMSELVES SEVERAL TIMES. Boost converter is ALREADY EXISTENT IN MOST (>90%) DEVICES THAT COST MORE THAN 10$. Also their claims are unfounded SINCE THE POWER CAPABILITIES OF ALKALINE BATTERIES DETERIORATE. EVEN IF YOU INCREASE THE VOLTAGE THE CURRENT WON'T BE ENOUGH due to rapid increase of internal resistance after 1.25 V. Anything more powerful than 2 Watts cannot benefit from a boost converter after that voltage. Claims that typical alkaline batteries use about 20% of their available energy ARE PURE BULLSHIT. BATTERISER, if it works optimally and does squeeze every last drop out of alkaline batteries (and does so safely), is probably going to increase typical battery life by about 20%, not 800%
HERE IS THE MINIMAL VOLTAGES THAT COMMON CHEAP DEVICES REQUIRE:
autofocus camera with flash: 1.3v
halogen flashlight: 1.3v
regular flashlight: 1.2v
headphone/CD player: 1.2v
portable LCD TV: 1.2v
pencil sharpener: 1.2v
AM/FM radio: 1.0v
electric shaver: 1.0v
quartz clock: 1.0v
remote control: 0.8v
Microsoft cordless optical mice have a cutoff voltage of 0.6v, and Logitech mice of 0.8v
ALL YOU NEED TO DO IS SWAP THE BATTERIES TO A DEVICE THAT CAN USE THE REST OF THE AVAILABLE CAPACITY
+Krasimir Ivanov Dude, it was a joke. Calm yourself.
I thought you were serious. WHEN IT COMES TO SNAKE OIL PHYSICS I NEED TRIGGER WARNINGS.
@Phil Weatherley You catch more flies with vinegar! I was pissed. LOL
Could you do a video on how to create a float charger?
My electric drill/flashlight battery charger charges to 4.0V, so that's like 3 times more longevity or even better. Great for the environment for sure.
I also charge my phone up to 75% for the same reason (only possible if rooted).
We can use a timer on the Wall plug for 4h then cuts of the charger
you gotta try this with your phone's battery. No danger of cheap wall usb chargers and faster charging.
I remember when Chris Boden of The Geekgroup kicked me out of their IRC for explaining how you do this. According to him it's insanely dangerous and should never be done. He seriously knows fuck all about a lot.
Why it is dangerous? This is Li ion not LiPO battery. So the explosive is not in the equation. Also Li Ion already has built in BMS or PCB nowadays to protect battery from overvoltage or undervoltage.
Any specific information about how do you kick from IRC? He should explain why it is dangerous and the explanation behind it.
You ask him.. He apparently knows more than anybody else in this world. He's also the guy who claimed that Corning optical USB cables don't work because "USB is a fussy bitch" ? Fake it till you make it..
These cylindrical li-on cells are safe, even these without afterparty protection circuits, because cell has inside safety pressure valve, fuse, and CID button(opens circuit when overheated).
But if you will smash positive side(where all these protections are) battery may turn into flamethrowner or even explode if overloaded, overheated or overcharged.
USB is indeed a fussy bitch! Implementing an interrupt or iso endpoint by hand in USB 1.1 and 2.0 gives me massive shivers.
But something interesting happened. Earlier USB protocols were limited by cable length because of latency issues. USB 3.0 apparently has ways of working around that.
Also i have a slight hunch of how some re-synchronization could be implemented for earlier protocols to offset latency of signal-converting electronics. But it would take a person a million times better than me to actually accomplish that.
But who is this Chris Boden person anyway? Never heard of them.
Electricguy Well, as long as you know what you're doing (and disconnect the battery at or near the cutoff current), it's fine. I'm not sure if I'd want complete amateurs attempt something like this though....
Dave, I can use a cheap manual set plugin mains timer + a mains relay to disconnect the batt + after 4hrs. Now, what's the situation with the diode mentioned somewhere below? What type and how connected or just thought, would it be at all necessary with my relay?
A question. Say that you wanted to charge a battery while it's in use. Similar to how a laptop charges it's battery with the power on. I take it that all you would need is a battery charger in parallel with the battery that is capable of putting out enough current both to power the device as well as top up the battery. Since the charger would limit voltage to 4.2 and reduce amperage as the battery charges, this should work right? I want to convert a remote control vehicle to be able to self charge with a dock and always be on, for a security robot.
are there any ic's that let you cut off charging when current reaches a certain minimum? I have been told its bad to keep lithium keep constantly float charging.
I charged it with my voltage supply, like you said.
But now I measure the cell delivers 4.14 volts, instead of 3.8
Nice video!
How about batteries with multiple cells in series? Is there a way to guarantee they are balanced using a power supply given the batteries have that additional connector they come with?
Great video bro, but at the beginning of the video you tell that you don't know the cut-off current, albeit it is written clearly on the datasheet and you will reference it later.
That's because I didn't see early in the video when I recorded that.
Great video,
Is it possible to charge 10 batteries in parallel using the same concept.
If so do you increase the current by 10 times?
for example if one cell safe charge current is 600amps putting 10 in parallel is safe to charge at 6amps???
Thanks
cant remember where but somewhere I read a while back that if they drop below 2.5v for any real length of time (a few months+) a chemical reaction takes place that can cause sudden internal partial/total shorts and possible fire/severe heat and venting, hence why the protection circuit will not allow you to charge a cell if it drops below about 2.5v. You can usually tell if a cell has a problem as it gets warm as you charge it... and a very good reason not to use unprotected cells...
That is an old wives tall (I have charged a battery that was at 1.4V for a few years without it heating up or swelling), the main damage comes from when the cell voltage is reversed.
I bought this same power supply because Adafruit suggested it. I'm glad to see someone else using it. I love my power supply, and yes I do remember when Dave bought this with the upgraded software. It's still nice to see someone else using it.
Can someone quickly tell me how to set the low current cut off that he didn't want to show in the video?
I'd love to get that supply, but it's way too rich for my blood. I have the $50 ebay special,which also can do this but it's a lot more of a bugger to set exact values on.
You press the button underneath the display labeled "current", and dial in the setting the same way you do for voltage.
That's setting the current limit. I'm talking about shutting it off when the current gets too low.
as far as i can tell, he was talking about setting a cutoff timer after x hours. I don't have the supply myself, but there's a timer button visible on the front- maybe that can help. Or just read the manual :)
I have experimented with using python via telnet and VBA (in excel) via VISA to DP831 to status and control. Works very well. DP831 (DP832 would be almost the same to control) is very open and relatively straightforward to control via ethernet. Suspect USB would also be an option.
Python would be my first option for battery charge control. Could also add safety shutdowns by monitor for weird battery behaviour like increasing current over time and OFF the output.
There was some clever front panel tricks hinted at in the manual that may help with with battery charging but I glossed over these as I figured programmatically would be the most flexible fastest approach for me.
do you set the voltage equal to 4.2 multiplied by the number of batteries in series so for example, 10s would be 42V
I'm a bit confused.. Why does it say 3.7V on the battery but we charge it to 4.2V?
...Even the datasheet says to charge it at 4.2V but the "nominal voltage" of the battery is 3.6/3.7V
Hi Dave, could you please comment on the document from Rigol "Active loads and the RIGOL DP800 and DP1000 Series". It says "an external diode should be used to prevent the flow of current into the supply and prevent damage of the power supply".
But the problem with a diode... the voltage drop depends on "forward" current. I think it will be hard to apply precise 4.2V to the battery.
The capacity graph in the data sheet says it switches from cc to cv at about 80-90%, not 50%.
It can be quite chemistry/manufacturer dependent.
Actually, it should say when the charger should switch from CC to CV. not when the cell does.
I have some questions.
When at the phase of Constant current. Your lab power supply will force the current deliver to always stay at 1.7 A, right ? While the voltage from your PSU does not matter as long as does not pass 4.2V limit.
And when the the voltage is at 4.2, your lab power supply will maintain the voltage at 4.2 from your PSU and let the current sinking?
Woud like to have seen you put the battery under a discharge tester to prove the success of the charge.
If you use a low charging current, you can get away with a very simple circuit. I have a 5v solar cell that puts out 300 ma at 3.5 volts, down to 25mA or so at 4.2 volts. I determined the current values empirically for my setup (expected illumination conditions) before proceeding. Works perfectly on this kind of cell, it just takes a day or so. I can leave the cell connected indefinitely with this setup. Works great if you're not in a hurry for that charge. I use a number of cells that I cycle through.
Well - as long as you 5V solar cell really never goes above 4.2 V that is.
getting the cell to 4.3 v a single time might already destroy it completely.
ABaumstumpf Its a new setup, about 10 days old now. The solar cell only puts out a trickle of current maybe one hour a day, when the battery is full. I will be watching it closely for a while. You are right in that it is an iffy setup. A bit of an experiment, which, so far, appears to be working.
I use a similar set-up, but I always use either protected cells or cells to which I've added a protection circuit. That ensures that once the cell has received a full charge, it won't over-charge and also once it discharges too low, the output will cut off.
any idea what settings could I use for charging NiZn batteries? they are 1.6V AAA and AA sizes
Can you charge a Li ion battery pack(13 serial for example) using this power supply method?
Hi great video! If a battery's rated capacity is 6820 mAh, do you set your power supply's current to 6.8 amps?
Hi, I'm little confused on a constant current state. It looks like it just limit the current to a set limit so its kind of a current limiter. Does the battery itself lower the current it pulls in the psu when it reaches 4.2V? I have a DIY 12V lead acid battery charger but i'm confuse because the current doesn't stay in the current limit it drops slowly while the voltage is rising slowly too. Maybe my battery is broken? My charger is a iron transformer type but has a switch mode buck converter with current and voltage limit setting feature.
Can you charge your battery at less that half capacity?
Thank you for this and what you do.
I'm still learning EE for personal projects.
Instead of an egg timer, watch, or smartphone alarm. Wouldn't it be ok to just plug the power-supply into an outlet-timer?
Absolutely. And I think he actually mentioned that in the video.
just wondering, if i was to charge 2 of these batteries in series, would i charge them 8.4 volts 1.7a for 4 hours max?
in constant current mode, can i use my constant current circuit 12v supply 500ma? then if the batt voltage is 4.2v ill disconnect
what if the psu is powered off but left connected to the battery?
use a timer box thing, for the psu
Have you played with some MPPT solar charge controllers? I'm wondering if there is one useful solar charge controller that can charge a pack of 18650 equipped with a BMS? The only one that I could find and can be programmed via their software on a PC is ProStar MPPT from MorningStar and it's like $480, Some other manufacturers charge a $150 fees on top for factory programing.
You can now get solar charge controllers which can be switched between modes to charge either lead-acid batteries or lithium batteries.
very good ! david. my name is john. my country brazil.
Can termination at 10% of charging current in the CV part of the curve be automated on DP832 / DP932?
So the voltage with which the battery is charged should always correspond exactly to the voltage that the battery has at exactly that point in time?
LiPo Batteries? Never heard of that abbreviation. So I guess you can call completely discharging a LiPo battery a LiPoSucktion? :)
Great video btw. I always thought you needed complex electronics to monitor the temperature and internal resistanance very accurately or otherwise your battery would explode on overcharging or completely brick it when discharged below a certain level. But I have to stand corrected.
3.25V is not always a dead battery, that depends on the specific cell.
I have cells that won`t die untill around 2.5V resting voltage..
(18650 high drain cells, both my sony`s and samsungs can live at 2.5 and 2.75V respectively, as long as they don`t SIT at that voltage over any period of time. I regularly have them down to 3.4..)
@8:10... "PING" --- we have ALL been waiting for that y'know... LOL HAHAHAHA!!!
The thing today is reviving a dead battery back. Personally to me the method used by many is to zap the pack, with a like good battery by connecting the packs in parallel for seconds, is haphazard.
While it is politically not proper for the consumer to rejuvenate a pack, having to scrap a pricey pack within months of purchase is a waste.
The pack I rejuvenated is a 18v, 36AH Hoover Links vacuum cleaner. It consists of 5 18650 cells in series and with a large circuit board. Each cell measured 0.14v except one, that one cell was 0.010v. This cell I charged at 15mA with the supply set at CC. The corresponding voltage was 0.5v and CV set to the same. Once the supply switched from CC to CV, I gradually, increments, set the CV higher while keeping the CC the same. Initially the supply took about an hour to switch from CC to CV, this change caused the current of 15mA to go 0.0mA. Eventually ended the charge on each cell at 4.0v with CC at 200mA, once the cell voltage reached 4.0v the charge current will drop to 0mA.
The pack appears to work OK now but unknown as to life compared to non rejuvenated pack. The battery packs appear to run at high drain because the vacuum only runs for 15 minutes when the motor goes noticeably slower and the power low battery indicator flashes. I suggested to the users of the vacuum to stop using when the indicator flashes/or sound of motor becomes weak. Do not run until it dies.
Can you do say 8AA batteries in series at the same time?
How do I change my power supply screen to a video monitor like you have in the thumbnail? I could really use that.
Wow, lol.
This will most likely be done in Photoshop, GIMP or some other image editing tool in post-production.
which are suitable power supplies to charge Li ion batteries , and which power supplies are a ""NO-GO "" ?
Does the same jazz apply to those little lipo nominal 3.7v mini quad copter batteries that were small rectangles?
Yes, as mentioned in the video
Think you should have mentioned why the cells cannot be charged in series (@8.4 - 12.6 etc). Also i thought a single was a "Cell" and more than 1 "Cell" is a Battery (which makes this a cell) ? Good work though.
How do I get my hands on some high current battery holders like those. I keep melting the thin gauge Jaycar ones out
is that an oled display u got on the rigol?
Thanks for the tweaks and additions Dave. This is now a bit safer :)
What about an under-discharged cell?
Let's state it simply : in 2016 (Amazon/eBay 1 day delivery), every one could get a proper charger for $10-15, and charge anything perfectly safely :)
Watch my tutorial video for info on under-discharged cells.