EEVblog

[@BrettAnsite]

Thank you for doing this, you helped me found my business 10 years ago and I really wanted to thank you.. I was able to do so much without having gone to school because of your videos.

[@craftymulligar]

Yeah I think Dave said he went to electronics school but built things before that that helped him self pass through.

[@DaCracky]

Your enthusiasm is taking me with you :) Just found you because I was suddenly wondering how li-ion batteries charge

[@roycohen2013]

Im 16 years old and ive been building all kinds of circuts and started using embeded processors like the AVR's not to long ago and I just wanted to say that I love your blog and its helped me so much with learning all these concepts :) so thanks for all your doing and keep it up.

[@gergelyurban6718]

I love the way the Aussies talk! :) All happy and positive 👍🏻

[@dizseal]

Dave - I've been watching EEVblog videos all weekend. Looking to get back into my hardware engineering roots. I find these incredibly useful and motivating. Thanks so much for all your work on them.

[@garrisonl.4673]

this guys amazing and very knowledgeable​. although he looks to have been filled with a couple hundred volts over time himself.thanks for the great videos.

[@MrDoneboy]

You've gotta love Dave's enthusiasm!

[@cjones4433]

Btw, great video!!!

[@arvindpandey4945]

@@MrDoneboy=0

[@Newton_Berry]

good job man

[@stevemorgan2976]

Thank you! I had very little knowledge of the charging characteristics of lithium ion cells. I watched a couple videos on the topic and came away confused. I didn’t know there was a constant current charge cycle followed by a constant voltage charge cycle. As always, I thought you explained it extremely well and I easily understood what you were saying. I have often said, how much you learn is not as dependent on how smart you are but how smart your teacher is. Thank you!

[@stclairstclair]

I come back and rewatch this when I'm getting fuzzy, Dave is the best.

[@RinksRides]

Actually past Dave, Li-poly are different from Li-Ion. Poly cells are prismatic and typically for high drain applications up to 30C, while most ion versions are for lower drain applications up to 20A and are usually manufactured as cylindrical cells

[@Blox117]

li po is li ion

[@DefekCs]

Overall Your videos are awesome, thanks - helps a lot! :) But story behind Li-ion, LiPo and LiFePo is a bit different. Li-ion: Vn = 3.6V (uses transition metal ion eletrolitic compound) LiPo: Vn=3.7V (uses synthetic polymer compounds as eletrolite lowering internal resistance... this is where +0.1V in avg comes from) LiFePo: Vn = 3.3V (same synthetic polymer compound as eletrolite + different anode that changes reaction electrochemically itself).

[@mikeselectricstuff]

One thing to watch is power dissipation on the linear chargers - at charge currents over a few hundred mA, you don't need too much input-output voltage differential before the charge time gets extended due to the charger going into thermal limiting. Most of the cheap ones aren't packaged to conduct heat out well.

[@mbart]

Minor remark: charging is never exothermic with respect to the charged battery. The heat production comes from energy loss, the energy coming from the charger. Charging must be endothermic, because the chemical reaction to deliver energy necessarily must be exothermic. Great explanation and great videos, BTW. Thanks a lot.

[@harrypehkonen]

"You really should know because it's interesting." Love it! :D

[@RobertGallop]

Love the video, Dave's back! Please keep up the long videos like this, this information, level of detail, and overall information is not easy to get elsewhere. I always feel like I've learned a bit more after watching one of these, please keep it up!

[@e.a.steutel7874]

Thank you for all the time invested. You have a knack for explaining

[@gsleazy1975]

Seriously appreciate the content as an aspiring creator / engineer trying to learn on my own. Advice is top notch. Bloody good channel and keep up the great vids ❤

[@blackfaithdoom9018]

Min 12:00 , what i dont get is . Does the battery voltage increase because the charger increases the voltage ? Or is the charger applying 4.2V constantly and still the battery voltage increases just slowly ?

[@Subfightr]

I love the passion! So glad you're doing something that you clearly enjoy. I hope that never changes

[@valordk]

Those Microchip chargers look quite a good deal for a simple application. thanks for the video Dave.

[@toastrecon]

Thank you so much, Dave! I was just thinking that I’ve seen more hours of your videos than anything Hollywood has produced. Lol. Your videos are amazing.

[@jesusstolemypants]

Your blogs are actually brilliant! Please keep up the inspiring and passionate videos!

[@nialldarwin]

Awesome. So many things I wanted to know about these batteries and their charging all in one video. Thanks. You've got a friend in Raglan!

[@tanishqbhaiji103]

Li-ion and Li-po do have a difference now some Li-Po have higher charging and nominal voltages and they are also also available in large capacity pouches where as li-ion are not and they have higher C ratings much higher compared to Li-Ion

[@Beaches_south_of_L.A.]

Dave Jones you are my favorite KZbin personality. I would follow you anywhere. I only wish that I lived in Australia because then I would ask if I could be shop boy. I would sweep floors, scrub toilets and dismantle electronics for you. I would work for beans and biscuits. I would put a cot in the broom closet and call that home. Is it true that you have a locker at the bottom of the sea where pirates disappear to?

[@bcsupport]

Yes, I totally agree. Dave, Im going to have to start donating with these real world tutorials

[@ivanv754]

Dave, thanks for the video. I don't know if you did this because of my post on the forum but it came just in time for me.

[@cuttingedgecool7235]

Excellent deep dive into Lithium Ion technology!

[@renukacharyathakare2527]

Best Video for understanding Lithuim Ion Charging process. Thanks Alot. Hope you upload Many more such videos dealing with electronics Stuff

[@EEVblog]

@vaneenbergen I totally forgot to mention the protection circuit built into the bigger cell I was waving around. You really should be using these protected cells, they protect against shorts, over-discharge, over-voltage etc. With the unprotected cells, you have to take more care, and either add your own protection circuitry and/or design your product properly to ensure the battery is not abused.

[@Stefan50326]

Hi, I want to replace my defective laptop battery from a 15 years old PowerBook G4. It's using US18650GR cells which are rated at 2100 mAh. They have no integrated protection circuit. Is it possible to change to XTAR cells rated at 2200 mAh or maybe cells rated at 2500 mAh or 3000 mAh? Will it change the charging process and damage my power supply by using a higher current? Will the protection circuit affect the laptops behaviour? Note: when opening the battery, it seemed like there is a built in temperature sensor for the whole package of 6 cells. Kind regards

[@TheCrazyInventor]

Damn, when I read the discription, I was all like "this is EXACTLY the info I need". Timing couldn't be better, Dave. Going to enjoy this one. :)

[@JamieHarveyJr]

Very helpful kickstart to my understanding of lithium Ion charging. Thanks!

[@393nimit]

Can you explain please how balance chargers are implemented for simultaneous charging to cells in series? Component level explanation as shown in this video would be appreciated.

[@EEVblog]

@blackmuzzle You can't just make that blanket statement that "modern cells" have no problem. Read the datasheets for all those Li-Poly cells I showed. 0.5C recommended as standard charge, 1C absolute maximum for "fast charge". Always read the datasheet, cell types and their recommendations are many and varied. Yes, some are specifically designed for very fast charging. The price you pay will usually be cell life.

[@jamesfacada]

Fantastic explanation! I worked on power supplies and converters and inverters and find this a really simple but good video explaining the whole thing of Li Ion and charging ckts!

[@majinkeyboards]

Willy Wonka and the Electronic Factory. Joking around aside, this is a very essential video, helped me a lot. Thanks!

[@EEVblog]

@chrisgj198 That's probably a separate blog on it's own, low battery detection and cutout. And that applies to any battery technology really.

[@b.s.9133]

you're amazing thank you allllloooot i was looking for such understanding from a long time

[@mikeselectricstuff]

Digital camera batteries for popular camera models can be a nice cheap source of ready-packaged batteries. Ditto camcorder ones, typically 7.2V, and also phone batteries. Just be aware that clones tend to have 10K resistors instead of thermistors...

[@benwrong6855]

Great info Dave!! cheers for your efforts!!

[@mikeselectricstuff]

@bcsupport You can get charger ICs for multi-cell packs. I've used a Microchip 2-cell one in the past

[@panospapadopoulos]

He is great! Thank you very much for the great tutorial. To the point and enthusiastic

[@legion2k988]

super later to the lipo battery thing. Thank you for your video and breaking it down for me.

[@jaywenden1939]

"the other kind of coke"

[@harshvirsingh2174]

If you could explain the working of the controller in detail, that'd be awesome!

[@sakama239]

Love this guy so much hhhhh "stick with me because this is easy!" lol it's a 40-min-video

[@BobElHat]

You can't push the cell to higher than 4.2V without damaging it (which might make it go bang). Unless you use a ridiculously low charge rate the cell will reach that voltage before it's 100% full. As the battery charges its voltage gets higher, so to maintain a constant current you have to keep raising your charge voltage. Once you hit the voltage limit you can't raise it any more, so the current starts to reduce and the last few percent takes for ever.

[@alexanderquilty5705]

Man it’s crazy that we’ve been using Li-Ion and Li-Poly for 10+ years.

[@dave9343]

Dave, we can always rely on you for very solid material, like this one, on Electronic Engineering. Thanks very much. Keep them coming. Question: 1/ In a charging system, like say on an Electric car (Completely Electric), where REGENERATIVE BERAKING charges the battery, how is this possible? Since, during the REGENERATIVE BERAKING charging process, the battery is still supplying power to operate the various systems on the car (i.e Lights, radio, the Mini fridge with the cold drinks etc). I would be very grateful if you could explain how the battery gets charged during breaking AND if possible, point me to any in-depth detailed reading material, and 2/ Would this explanation apply to other battery types such as Led Acid 3/ Where could I find in-depth detailed information on Lead Acid Battery charging. Thanks very much.

[@lorcanbonda1241]

All Lithium ion polymer batteries are lithium ion batteries, but not all lithium ion batteries are lithium polymer. Those which are not "polymer" are the ones which catch on fire because the electrolyte is so flammable. In polymer electrolyte batteries, the electrolyte is bound in the polymer.

[@psyzanzan]

Hi, im from the future! Thank you for this retro lithium based batteries tutorial, now days we just use flux capacitors.

[@psyzanzan]

well duh, it becomes a cold fusion reactor and generates perpetual motion .

[@psyzanzan]

yeah i only use the baterizer when i need to get 1.21 GigaWatt more out of my Mr.Fusion.

[@psyzanzan]

you're right.i've had that happening to me in galaxy s7 wich ended up destroying the whole universe so i've hooked up a 1N4148 to gnd to prevent any reverse polarity. i only have 4 alternate dimensions points left on my driving licence.

[@MrBobman49]

The 4148 is a silicon diode which is nominally 0.7V drop. You would be far happier using a 1N5817 which is a Schottky that drops 0.2-0.3V.

[@OpenGL4ever]

How many flux capacitors do i need to drive a Death Star and make the battle station fully operational?

[@xuanthangang1675]

Thank you, I'm student at College of Viet Nam in 04/11/2024 and this video is helpful :3

[@Derfboy]

It's been 11 years since this video was posted and I'm here because I've never built a charger before and I want to learn how.

[@mikethespike056]

I'm here because I want to learn how phone batteries work.

[@enriquecourtade]

Hi Dave, I'm not fully agree about the amount of energy accumulated since the voltage reaches 4.2v and the current starts to fall. I have bought an Icharger 206B and made some experiments with the three types of balance modes it brings. I have logg all the charging proccess data and I would like to share it with you because I know you will get more information about them than me and maybe make another intersting video. If you are interested in, please let me know how to send you the data. The software I am using to see the data is LogView Studio.

[@wiinick90]

Wow. Totally helped me out. Fixed me a wireless speaker but in turn, the charger circuitry died. Now I can fix that bad boy.

[@carlosmejia6660]

"Iudadaniaamericana

[@bcsupport]

@TheCrazyInventor Yes, I totally agree. Dave, Im going to have to start donating with these real world tutorials

[@vincenttelfer4206]

try 3 battery packs in circulation on samba, keeping 1 pack for the load 1 charged and waiting or charging and 1 on charge , this way there's no charging and discharging simultaneously

[@pavelgrigorev4739]

Amazing Video! Thank you, for helping to write my tesis with your videos.

[@klantdunk]

The main thing that is reducing the capacity is the discharge rate. The difference between 1C and 2C discharge is about 3% for 300 cycles. Of course, this differs between batteries also.

[@GarrettBroadnax]

That was exactly what I needed. I'm interning at NASA and we're building a prototype lunar lander and rover that powers a Li-Ion/Li-Po off solar panels and we were having trouble charging and some other things. I have a question though: Why is part 2 of the charging process (I believe it's called trickle charging) necessary? Why can't you just charge using the part 1 method up to 100%? Is it a safety thing, an efficiency thing, or something else? Thanks

[@sudarapremathilaka1706]

Thank u so much.This is a great tutorial.This solved all my problems about Li-ion/Li-po battery charging.

[@mikeselectricstuff]

@TheEPROM9 Reminds me about 15 yrs ago I made a portable BBC micro - used the original case with a 320x240 mono EL display in the lid, and PSU full of nicad D-cells and a DC/DC converter. ISTR I had to mod the sound circuit to run without the -ve rail.

[@ProfessorFartsalot]

Most newer dell laptops flash the charge light towards the end of charge, I suppose that means constant voltage.

[@violincrafter]

fully charged, bob’s your uncle

[@avalon449]

As usual, very informative Dave. Thanks.

[@operator8014]

I've seen a lot of manufacturers state the "full" current as .03C, or 3% of the batteries A rating, so remember to check that before charging one. Don't just go with 10% as a universal rule.

[@jort93z]

its better to use a higher value. it doesnt really matter if your value is a little higher. unless you need that 1% more charge on it. you won't get more then a few % more amps toward the max capacity if you use 3% instead. if you use 3% even though your cell is 5% it'll never stop charging(which is bad). if you use 10% instead of 3% it'll just a stop a little sooner. and its not charging very fast at the last few percents anyway since the amp's already dropped all the way down. if you set it to 10% it'll finish charging a lot faster(not to 100% however) for a little less capacity.

[@BaldTom]

Lithium polymer is different to a standard lithium ion battery. Li ion polymer has a plastic electrolyte, while lithium ion batteries have a liquid electrolyte.

[@rikvdmark]

Nice video, very educational :) I'm building a charger using a MCP73833. The datasheet mentioned a design with a mosfet and a Schottky diode to isolate the load behind the charger. This negates the (possible) issue of the system connected to the battery from being affected when the battery is charged.

[@EEVblog]

@bcsupport Most chip manufacturers have devices designed for more than 1 cell. It's usually an option in the parametric search table. You can't just use a single cell charger chip with those.

[@Daitomodachi]

Hey Dave, will this method work for RC lithium ion battery packs?

[@DaCracky]

yo did you find it out? justcurious

[@trongv]

@@asificam1 q

[@thecraftsman8083]

All circuit diagrams are super simple for this guy!😂

[@TheCrazyInventor]

Oh, I don't mind "long" video's like this. Please don't make them shorter. I'd like to have all the info on a particular subject explained to me in one go. I don't want all that information crammed in 10 minutes, or something. I also don't like video's that just explain the basics of some concept really fast. That's why I like your video's: long and detailed information. Going to have a look at a supplier for these batteries and for their charger ICs. Very useful for my next project. :)

[@TonyLing]

My IMax charger has a 3.6V setting for LiIon and 3.7V for LiPo, so surely there is a difference?

[@frankjoshum]

Haha I had to google "Bob's your uncle". Great stuff!

[@debasis2196]

very informative.......for my phd work.....thank you for this wonderful video

[@hs4u537]

Is there a video on charging unprotected batteries? Would a charger know when a unprotected battery is full? If not how do i tell if battery is full or at the end process of CV if time not available on data sheet and cant measure current

[@stclairstclair]

Look at his video on charging Li-ion with a bench power supply, That explains the rest.

[@demoniack81]

3.7 is the nominal voltage. The charging voltage is either 4.1 or 4.2, if you don't know be safe and keep 4.1 ;)

[@pocketmoon]

Maths is cool - the area under the blue curve should be close to the stated capacity of the lipo. If you log current to a PC from USB enabled DMM you can just load the data into excel and work it out :)

[@ianhennus1518]

Hi I need to charge a li-ion 3s pack with my car alternator (14.4V). Because the alternator could overheat I want to manage the current to the battery. (cell balancing is handled trough bms)The thing is my charge current should go up to 60A, I can't find these kind of chips for these currents. Do know a solution/ circuit/ chip for this problem? Thanks

[@Duxa_]

i got a little pump that uses a lithium ion 18650 battery, the circuit reposnsible for charging it failed (Water got in)... everything else still works. I take it I cant just bypass the circuit and use iPad or iphone (5v 1a or 5v 2a) charger to charge the battery? I need the little circuit?

[@EEVblog]

@vaneenbergen Lithium Ion Polymer are more robust than Lithium Ion. But if you are really concerned, try LiFePo4 as @Pook365 said, they are much safer and won't go exothermic.

[@papalevies]

Hey Dave, why don't you make a video about small photovoltaic cells, MPPT and such

[@davidnelson1711]

How do these chips detect the true battery voltage during charging? I thought the battery voltage when there is a charging current and the battery voltage when no load is applied is different.

[@jaackmcmahon8757]

My battery has 3 terminals and is for a Wacom PTH-851 graphics tablet. How can I utilize the 3rd terminal in charging Li-Ion batteries???

[@AshwinVijayakumar]

Can you please talk a little bit about battery protection circuits and how to protect the battery with MCP73831 + LDO configuration against under voltage discharge (over discharge).

[@chrisw1462]

@34:35 The 'Charge Complete' leakage current listed is _negative_ - a.k.a. float charge.

[@snaprollinpitts]

thanks Dave! that was pretty easy.

[@kevin29wong]

Man now I want to try some of those batteries, especially the bendable one.

[@florianklar6100]

It's pretty simple on paper but I'm having a super hard time finding a 250mA charging board that doesn't require me to replace an extremely small resistor to set the current.

[@cjones4433]

So I would like to make a 2 cell specific use charger for a lifepo4 batter charger. Are there chips for that?

[@EEVblog]

@mikeselectricstuff Yep, good point Mike. Could probably do another whole blog on just how to implement the charger IC's. Many of the packages like DFN will have thermal pads on the bottom to help with dissipation. The on-chip die temp monitors usually kick in around 120degC and limit the charge current.

[@zero3609]

I have a 3 (in parallele) cell Li-ion batt from sparkfun (google finds them quickly) and Im having a lot of trouble designing a charger for them because all of the Li-ion charger IC i find specify the they only charge One cell batteries but Im not sure if they refer to one cell in series or parralel? thanx in advance for any help.

[@duanecjohnson]

If they are truly in parallel, then this would be defined as "One cell". For this case, the current ratings for the charging circuitry would be three times that of a single individual cell. However, the advertised specs for the whole battery may be rated for all three in parallel already. redrok

[@Mnorbert25]

a flywheel diode is used to mosfet to protect it from damage but here is not needed because you don't have any coil,also I forgot to mention that the flyback diode it's already build inside the mosfet.

[@IndustrialGoblin]

Thank's a lot, Dave! Love your videos! And you inspired me to make my own.

[@sathishjo6511]

I have a doubt.. If I have a Li-ion battery with capacity of 1Ah and my battery charger IC is configured to deliver 1A current to charge the battery, what would be the time taken to charge the battery completely? Is it 1 hour or more than 1 hour?

[@HarmonicResearch]

Why is my 48V ebike battery only rated at 5A max. charge current when discharge is rated at 20A max?

[@Last_outkast]

I probably missed it, but is there a maximum amp hour limit for charging? Like if you had a charger ment for one battery but you put a 100 batterys in parallel what would happen?

[@swededude1992]

Alot of youtube videos shows how to build batterypacks and how to charge them. One thing I don't find an answer on is: If I build my own charger for a batterypack, should I treat the entire batterypack as 1 large battery, OR, shall I treat each battery in the pack as individuals, and adjust my charging accordingly for each individual battery? :)

[@DEmma1972]

I just bought a 'hoverboard' that has a 42v battery pack (I think its 20x18650). The board was hardly used and the battery died and is now showing only 3.1v. Is it possible and safe to recharge this?

[@Falcon_Overland]

Presuming it’s fine for the alternator, can you use an alternator directly as a charger for big lifepo4 packs? It puts out a Constant voltage of 14.6. And current is limited to 100 amps. It costs a lot to get a 100amp ic

[@Kingshukpalchoudhury]

What happens of you charge at lower currents than 1/2c The generic power bank charging mpdules only put out about 1 amp While the batteries used are usually 2000mah or 3400 mah 18650 type batteries in parallel.. Giving capacities ranging from 5000mah to 20000 mah It will charge slow, but what impact does it have on the life span?