Any cells from sellers like that are usually genuine. They are the manufacturers, they sell cells that they did not or cannot sell to sansung. For example, it may be slightly out of spec, such as slightly low capacity, slightly lower discharge rate, etc.
I think the liitokala battery you are testing is not a "25R" it's a 25R6m (SDIEM), a variant of the 25r except that it's made by Samsung Malaysia. This battery is referenced on the Mooch's website.
Tape an NTC (thermistor) to the cell and plug it into a multimeter. BTW, temperature of the cell is related to its internal resistance. Cells with a high C-rating have a low internal resistance. If you discharge a cell with a high internal resistance (low C-rating) with too high a current, the cell will build up heat internally very fast and it will get extremely hot. In order to determine the C-rating you need to measure the internal resistance, which BTW, is not constant. Internal resistance is related to STOC (state of charge) and temperature. So IR can be seriously different under different conditions.
Just after buying , testing immediately the Internal Resistance (not always easy because the result can change , but possible if it's done in the strictly same conditions) gives the same information, quickly, without any damage for the cell, and the regular repetition after a few months gives a good idea of the (good or bad) evolution of the battery. Most important is not to know if the battery is fake or genuine , but if it's good or not... RI is the most reliable test to know that , because it's an indirect but reliable indication about the Out-amperage possibilities of the cell. So your test ( even if not good for the battery) is also a solution, but not necessary , and it must be compared after 50 , 100 cycles...THIS is the real test for battery quality...and battery life.
But if you don't show a bad fake cell then this test does not do much better than your word without test at all, even it would be much better to test just a bad cell and say words for good one but again if you test then you test all if not then don't. You should compare good vs bad or was this video just commercial for your battery caps ? I am sorry if this sounds harsh but it is true and honest.
It is nice to know where to source 18650 cells for the majority of the planet outside the USA. Goods either do not ship outside the USA or shipping is three times the cost of the original item. Keep up the good work.
how many times did you purchase from aliexpress liitokala? I did some research and it seems that there is multiple accounts on aliexpress claiming to be official liitokala store, also found some people complaining that after several purchases of good cells they got fakes from same seller, somebody on one forum did post the business details on all these accounts (Im new to aliexpress and still dont know how to check business details) and it seems that all these accounts have almost identical business details, also on the reviews many people claim to have bad cells, one guy bought 10 and received 5 good and 5 fake... so Im really curious are you affiliated with liitokala or you really purchase regularly from them and have always good cells?
I agree with you, we have tested many of them on Endless Sphere and way more are copies than not. But the China copies are still not bad cells at lower amp draw. Just think how can LiitoKala sell their cells cheaper than the genuine manufacturers like LG Samsung Sony etc can make/sell their cells for...
I am doing a degradation study with Liitokala NCR18650B cells, and for now (over 240 cycles) they still have a capacity of over 2900mAh. I leave you a link where you can see it: electrotinker.com/en/analysis/degradation-ncr18650b-liitokala/
@@diegodbg86 This is interesting, could you do "Lanzhd" cells too? They are also from China but seem to be the most expensive ones I've seen compared to littokala and varicore.
Great video, very helpful. Can you do another video on 21700 cells? Maybe comparing them to 18650 and what are the best ones for an e-bike battery pack?
you not want china fake cells.... they are bad for ebike battery.... can explode or bad issues after 100+ cycles.... not nearly as good quality as genuine... which is hard to tell these days... they are experts of replicating weight of cell. exterior packaging etc... 7 years ago i remember they had AAA Replica beats by dr.dre headphones... and they were really hard to tell... its 2020 almost they have real good replicas but they are fake cheap crap
Wouldn't a simple internal resistance test be easier? Especially if you're only comparing one cell to another. You're essentially measuring the same thing, only at its source.
Thank you for always educating us and for providing us with the resources for our DIY projects! Also, I love the Jumanji-like music during the fast-forward portion of the discharge demonstration!
Would love to see a video on how to hide away all the cables/plugs when doing a conversion. There are kits around lately with neat cables and plugs, but they don't leave many options on the user.
Yea, cable management is always a problem. I like to use spiral wrap and then zip tie to the frame. It’s not a perfect solution but it turns a mess of wires into more of a single log.
Temperature of the cell is mostly related to his INTERNAL RESISTANCE.. and with the resistors you have you can easy measure it by discharging it at two different currents and do the math. It is a very quick way to tell you if the cell are fake or not right on their specs. Doing the test this way will ensure you that you are not affected by any parasitic heat source or thermal isolation material.
11/11/2018 I purchased a large number of cells from the Liitokala Official store and was shorted about $200 dollars worth of cells. I'm currently in a dispute with them over it. They are not willing to look at the pictures of the packaging and discrepancy in their shipping labels. I hope AliExpress steps in and makes this right because, Liitokala The official Store, certainly isn't going to.
Great video! I have a Littokala 4x charger which does a full cycle test of charge/discharge/charge, with LCD display and individually programs each slot. Cheap to buy too!
Is the watt meter absolutely necessary or can you just connect the power resistors straight to the battery (assuming you can measure voltage another way)? By Ohm's Law, 5x 1ohm in parallel should give you 21amps, or am I missing something? I guess the cells themselves limit to 15A discharge? Planning to get started in battery building.
Doesn't the voltage keep dropping ( changing !!! ) from the beginning of the test, until the end of the test? Who said, "all cells are limited to 15 amps discharge?"
@@MrSummitville yes, that's why I mentioned if you can check voltage another way like using your multimeter to monitor when it goes down to 2.5V, because I don't have a watt meter. I guess to clarify my question, is the amps controlled by the 18650's rating or the by resistance? Because if 5 resistors draw 21A from a 15A-rated battery, will it damage the battery?
Good informative video thanks - I am going to try to do the same. Don't you think it would be a good idea to have a switch in your circuit, just in case a cell gets fast very quickly..?
Great information. I think I will give Liito Kala 18650 a try. My only concern is the longevity of the cells, but only way is to give it a try. 18650 cells also seem to be hard to source these days! Good to know there are reliable 18650 sources on Ali Express.
Just a warning, Liito Kala cells are also “faked” by other sellers since the brand has recognition. Posts on forums of Liito Kala branded cells not meeting discharge specs are all over, no way of knowing if they were actually from Liito Kala or some cleverly named Aliexpress store trying to pass themselves off as Liito Kala. Mica’s method here is without a doubt the best way to test cells since high discharge cells are much more expensive than low discharge cells so the only way scammers can profit off fakes is to use cells with a 5A discharge that are half the price.
Be careful using any infrared camera for accurate temperature readings. Different materials and finished greatly impact accuracy. For example copper and aluminum fact as a mirror, you see you own reflection skin temperature or other not the object. Every matteriaa and it's specific finish has a specific emissivity factor that you you use to calculate the actual surface temperature of the material. There is a way to find and accurately calculate a mayterials emistivity so accurate temperature readings can be take. You can't rely in charts due to perceved finish issues, best to test. A trick thermigraphers commonly use to aquire accurate infrared camera temperature readings is to stick some black electrical tape to whatever your measuring, it has a known emissivity eliminating innaccurat temperature reading issues with reflected heat, material differences and finsh differences to aquire very accurate infrared camera tempuratures. The infrared camers temperature innaccuracte is the same for a $10,000 infrared camera or a $200 camera. So when using an infrared camera it is best use to compare things to find heat issues not for accurate temperature reading unless you know the matteriaa being looked at emissivity and consider if the matteriaa acts like an infrared mirror so your seeing the temperature of some other matteriaa like your face. The art and science thermograohy can get complex for accurate measurements. Have fun, be safe. Be aware that infrared camera temperature reading accuracy changes material type and it's finish, best to test to find it's actually emissivity or apply electrical tape to it for consistent accurate temperature readings.
agreed, plus how hot are your resistors getting during the test? their resistance changes as their temperature changes ( resistance is accurate only at 25 deg Cel ) one needs to typically use a resistor 4X's or higher the wattage calulated, and then it should be heat sunk as well. ( that's what those holes are for on those resistors ). not doing this will give incorrect voltage drop/current measurements. informative video nonetheless
I want to make up a replacement set of batteries for my electric skateboard, but the sheer number of 18650 cells that are available are overwhelming. With everything from 3500mah to 9900mah. What specs are important for electric personal vehicles? What do I need to look for specifically?
Under these circumstances I would say you are correct. I will feel good buying these batteries. Long term would be a good test. Thank you for the video.
I'm hoping to build a 52v electric bike with the new kit. I would like to build at least a 4p pack. Will you have more size options available for the new kit? Also do you think that will reasonably fit on an ebike? I'm planning on a mid drive fat bike. Super excited to get started.
I agree with your test,always impressed by ur knowledge.Just a little example:you buy a bunch of cells from a Chinese supplier from any E-portal,and throughout that test u discover they are fake or not matching the quality declared by the seller.After contact the seller about the problem you won't have a penny back from them.This is a fact.Buy from sellers that are accredited and give u warranty,better with a physical shop,u get for what u pay.
Since you seem to be doing more individual cell testing, I would look at getting an icharger 3010b or one of the more expensive models to do discharge tests. You can actually graph the discharge curve and cell temperature with those chargers.
Hello. If you have to buy, for example, 130 cells to make a 13s10p configuration, once you test and detect that most of them are inferior, and you've already spent a lot of hard-earned money, you sense that there is a tremendous difficulty to get a decent battery.
fake crap bomb fire ,,, only good for vape using 1... using 130 is not good !!... . I would sell them off... dont use it maybe it will be okay but after 50-200 cycles you will notice very unbalance and not capable of continuous output stated (or remotely close even) than it is dangerous. Gotta buy genuine....
18650 Lithium Ion Battery Identification Reference Each battery in this list has a picture, a description, a link to data sheets and relevant URLs, as well as brand/model/capacity/discharge rate/battery chemistry. If you need to identify a battery cell this should be your starting point. this is a PDF hosted on Google drive, you can view it from the page or download it to keep as reference. drive.google.com/file/d/0B9KXttJ6nbz6VWUtcUtvZEY3dWc/view Source: electricbike.com/forum/forum/knowledge-base/batteries-aa/27729-18650-lithium-ion-battery-identification-reference
My ebike cut off under heavy load. I can start again after just a short brake and I don't know if this is because of LVC (Low Voltage Cutoff) or that my BMS is faulty or that I'm just drawing to much current. This usually happens when my battery is getting down to around half capacity. I don't know where to start testing but I think it would be a good topic to investigate. How do I fix this?
Interesting... haven’t seen a lot of temp testing. I did just buy a liito-kala charger to be able to test more cells! Could you make a battery building video using mixed capacity recycled cells and maybe compare its performance on your bike! Great video!
Nice video thank's. How would you test 60 cells, I have a pack and some of cell are getting old (they don't charge anymore and have a very low voltage) And How can I be sure that the kepping cells are still good and are going to last some more years.
Maybe you addressed it somewhere else, but I'm confused over the 20 amps continuous comment on the samsung 25r. It's a 2.5 ah battery. at a 20 amp load, that would indicate 5 minutes or less to dead? I thought these batteries were .2C for charge / discharge? 2500mah * .2 = 500ma charge / discharge. Am I off?
batterybro.com/blogs/18650-wholesale-battery-reviews/30828867-is-it-a-fake-18650-battery-featuring-the-samsung-25r look at the specifications... 2.5Ah so with 25A load max 6mins I think standard charge 1.25A for 180min
Do you think that you could get fake from liitokala? For example when you buy one and you check it and it seems legit would you test others when you buy from them. I mean do you test all of them or just one from all.
If want to series 2 stack of 2*26650 parallel, and that each batteries is protected by a pcb, do I needa add a bms to the circuit? I want to achieve ~7.4v and increase capacity over only 2*26650 series Thanks
Hi Can i ask you something why are the nitecore battery and olight so expensive and are the better the LG Panasonic or Samsung cause those cost 5 Euro and Nitecore and olight around 25 euro
why you dont have the digital version of yours books? I buy the DIY Solar Power, but i live in Portugal (Europe) takes a eternity to arrive . I whant to buy the ebike guide but if possible in digital version. Thanks
Do you have a video or what can I use to bulk discharge for storage of 18 650 batteries and have a Automatic cut off at 3.7 V. Thanks I just love all your videos very educational
hello i am waching your videos. i learned a lot. thanks. i have one question as i plan to build my own bike battery. why not using a balance charger like used for rc li battery packs charging instead of building a balancer into the pack? thanks an regards hartmut
A balance charger is definitely an option, but for ebikes it is less convenient because those chargers get expensive when going over 6s, requiring complicated charging of one pack broken into multiple parallel packs if you want to use an inexpensive charger.
I try to follow people who are battery geeks. It's not easy to sort it out, and there are economic interests who don't want DIY stuff to work. That's pretty much top to bottom the ebike industry in the US, retail side. So right now I can follow the link to Liito Kala from your recent ebike review. There I find cells for $2 apiece if I simply buy ten cells. They say free shipping, and maybe it is legal shipping. I have 80 2200 cells I got from the Jehu/Tom thing last year. I've been checking them with the BT-C3400. You can pick that up during Ebay sales for a reasonable amount, and it makes checking the cells pretty effortless. Now I know precisely what the cells do, and that is reassuring. You have a compression battery pack system. Gee, Jehu now has a compression battery pack system. You have links to batteries. Jehu has links to batteries. For years the purists rejected compression packs out of hand, but that was maybe because a lot of people wanted performance. If the springs can manage 3A and you have 3 parallel sets, a 36v battery can give you 350 watts or so. But no one is testing this out. There are projects. I have the Vruzend V1 and some cell holders like Jehu is using. The Jehu holders are very standard, "I've done this" kinds of deals. If you had a 30 cell battery pack built around that sort of cell holder (and it worked) it would be interesting. I really like the Titan 6s packs that can go together with XT60 series and parallel connectors, to make a bigger pack. But Trent is at $8 a cell, which is way too high, and he's marketing to RC users. A 6s pack is a good building block. You had that Maker system. Nothing ever goes very far, I guess, though Titan seems to be doing well with RC. If I bought something like that little folder for $500, I'd want to be able to put together a $100 battery pack from something like what you or Jehu suggest/link. Any bike should be that 'hackable'. You don't say, on that bike. There's a lack of energy in the ebike space. I guess there is more in the power wall space, but I'm not sure where that is going.
Hey... I know this an older vid but I want to run a similar test. Do you have write up or link to amything on wiring the resistor setup u used? Its hard to tell from this vid how all the wiring is in your rig. Thanks
Great videos & tutorials, thanks for the info! I’m planning on building a high-current battery pack using 30Q cells with a 20A discharge per parallel cell. I understand the most common nickel strips (7-10mm by 0.15mm) can only handle between 5 to 10 amps each. What would be your advice then? Multiple nickel strips on top of each other or maybe something else? Thanks!
My questions is that those battery work great for the price? I was thinking to buy new battery to build a power wall, this could be a great option? Thanks for your videos. BTW I’m a mechanical engineer like you.
Hi So this vid was posted a while back just wondering are u still happy with the batteries you purchased and shared a link to on AliExpress on, and do u still endorse them ,thinking of buying some ,but being a family man monies are tight so just looking for an update Cheers Gaz
Which battery, how many battery, what mah do u recomend to make 60v 30ah with 60a discharge for 60v 2000w hub. The lesser battery the better😁 Better than LgMJ1 or just stick to LgMJ1.
i went and looked at the v2 battery kit..... a true kit for a beginner would have all parts to build a battery, being new to this i don't know what i would need, but i am interested in trying it... i have been reading and working on my own solar system ..... i like the idea of the caps to build, I am not good at sodering .
I’m new to all this but trying to learn I love watching your videos you are a awesome teacher keep it up. So I have a few questions why do you use 18650 and not 26650 batteries? I want to make a battery for my boys razor four wheeler I want to upgrade the motor to a 36v 1000w motor. I’m just really confused on which batteries to use fo this any help would be awesome. Thank you!
Litokala cells are purchased Direct from the Manufacturer so if you are outside of the US id Recommend them for any type of cell. I've bought some myself and they have all preformed to rating and spec
They're probably genuine, but judging by some of the reviews they could be selling refurbished cells, so they might not have 100% of the original capacity or cycle life left. And that would be really hard to test, but it would explain their (seemingly) impossibly low prices.
FAKE! Do not BUY! They have genuine Samsung picture, but what you get looks similar but it’s not! Just remove litokala sticker, and there is no Samsung inscription under. Also "+" cap is not the same as Samsung. Also, I have tested them on 10A. They cannot do it, voltage drops to 3V almost immediately. Again: DO NOT BUY.
Any cells from sellers like that are usually genuine. They are the manufacturers, they sell cells that they did not or cannot sell to sansung. For example, it may be slightly out of spec, such as slightly low capacity, slightly lower discharge rate, etc.
I think the liitokala battery you are testing is not a "25R" it's a 25R6m (SDIEM), a variant of the 25r except that it's made by Samsung Malaysia. This battery is referenced on the Mooch's website.
Tape an NTC (thermistor) to the cell and plug it into a multimeter. BTW, temperature of the cell is related to its internal resistance. Cells with a high C-rating have a low internal resistance. If you discharge a cell with a high internal resistance (low C-rating) with too high a current, the cell will build up heat internally very fast and it will get extremely hot. In order to determine the C-rating you need to measure the internal resistance, which BTW, is not constant. Internal resistance is related to STOC (state of charge) and temperature. So IR can be seriously different under different conditions.
Just after buying , testing immediately the Internal Resistance (not always easy because the result can change , but possible if it's done in the strictly same conditions) gives the same information, quickly, without any damage for the cell, and the regular repetition after a few months gives a good idea of the (good or bad) evolution of the battery.
Most important is not to know if the battery is fake or genuine , but if it's good or not... RI is the most reliable test to know that , because it's an indirect but reliable indication about the Out-amperage possibilities of the cell.
So your test ( even if not good for the battery) is also a solution, but not necessary , and it must be compared after 50 , 100 cycles...THIS is the real test for battery quality...and battery life.
But if you don't show a bad fake cell then this test does not do much better than your word without test at all, even it would be much better to test just a bad cell and say words for good one but again if you test then you test all if not then don't.
You should compare good vs bad or was this video just commercial for your battery caps ?
I am sorry if this sounds harsh but it is true and honest.
It is nice to know where to source 18650 cells for the majority of the planet outside the USA. Goods either do not ship outside the USA or shipping is three times the cost of the original item. Keep up the good work.
how many times did you purchase from aliexpress liitokala? I did some research and it seems that there is multiple accounts on aliexpress claiming to be official liitokala store, also found some people complaining that after several purchases of good cells they got fakes from same seller, somebody on one forum did post the business details on all these accounts (Im new to aliexpress and still dont know how to check business details) and it seems that all these accounts have almost identical business details, also on the reviews many people claim to have bad cells, one guy bought 10 and received 5 good and 5 fake... so Im really curious are you affiliated with liitokala or you really purchase regularly from them and have always good cells?
I agree with you, we have tested many of them on Endless Sphere and way more are copies than not. But the China copies are still not bad cells at lower amp draw. Just think how can LiitoKala sell their cells cheaper than the genuine manufacturers like LG Samsung Sony etc can make/sell their cells for...
now cycle them 100 times and see how they compare.
I am doing a degradation study with Liitokala NCR18650B cells, and for now (over 240 cycles) they still have a capacity of over 2900mAh. I leave you a link where you can see it: electrotinker.com/en/analysis/degradation-ncr18650b-liitokala/
@@diegodbg86 This is interesting, could you do "Lanzhd" cells too? They are also from China but seem to be the most expensive ones I've seen compared to littokala and varicore.
Excellent video. I learned many new things. The 25R is my favorite battery so far so this was especially helpful.
Great video, very helpful. Can you do another video on 21700 cells? Maybe comparing them to 18650 and what are the best ones for an e-bike battery pack?
you not want china fake cells.... they are bad for ebike battery.... can explode or bad issues after 100+ cycles.... not nearly as good quality as genuine... which is hard to tell these days... they are experts of replicating weight of cell. exterior packaging etc... 7 years ago i remember they had AAA Replica beats by dr.dre headphones... and they were really hard to tell... its 2020 almost they have real good replicas but they are fake cheap crap
do you mean tesla cells ? I dont think they're available yet, tell me if I'm wrong
How about a comparative internal resistance test measurement for each cell , respectively ?
Wouldn't you expect them to be similar ?
C'mon man. If you would just remove the "Litokala" sticker, you would see there is no "SAMSUNG" inscription on the baterry.
Wouldn't a simple internal resistance test be easier? Especially if you're only comparing one cell to another. You're essentially measuring the same thing, only at its source.
Thank you for always educating us and for providing us with the resources for our DIY projects! Also, I love the Jumanji-like music during the fast-forward portion of the discharge demonstration!
Would love to see a video on how to hide away all the cables/plugs when doing a conversion. There are kits around lately with neat cables and plugs, but they don't leave many options on the user.
Yea, cable management is always a problem. I like to use spiral wrap and then zip tie to the frame. It’s not a perfect solution but it turns a mess of wires into more of a single log.
Good video. I'm learning a little, step by step, about batteries thanks to this channel. Thanks!
Temperature of the cell is mostly related to his INTERNAL RESISTANCE.. and with the resistors you have you can easy measure it by discharging it at two different currents and do the math. It is a very quick way to tell you if the cell are fake or not right on their specs. Doing the test this way will ensure you that you are not affected by any parasitic heat source or thermal isolation material.
11/11/2018 I purchased a large number of cells from the Liitokala Official store and was shorted about $200 dollars worth of cells. I'm currently in a dispute with them over it. They are not willing to look at the pictures of the packaging and discrepancy in their shipping labels. I hope AliExpress steps in and makes this right because, Liitokala The official Store, certainly isn't going to.
Great video!
I have a Littokala 4x charger which does a full cycle test of charge/discharge/charge, with LCD display and individually programs each slot. Cheap to buy too!
Is the watt meter absolutely necessary or can you just connect the power resistors straight to the battery (assuming you can measure voltage another way)? By Ohm's Law, 5x 1ohm in parallel should give you 21amps, or am I missing something? I guess the cells themselves limit to 15A discharge? Planning to get started in battery building.
Doesn't the voltage keep dropping ( changing !!! ) from the beginning of the test, until the end of the test? Who said, "all cells are limited to 15 amps discharge?"
@@MrSummitville yes, that's why I mentioned if you can check voltage another way like using your multimeter to monitor when it goes down to 2.5V, because I don't have a watt meter. I guess to clarify my question, is the amps controlled by the 18650's rating or the by resistance? Because if 5 resistors draw 21A from a 15A-rated battery, will it damage the battery?
Good informative video thanks - I am going to try to do the same. Don't you think it would be a good idea to have a switch in your circuit, just in case a cell gets fast very quickly..?
Very informative. Looks like ill need to build up a resistor load setup for battery check out. Awesome video and thanks for the v2 battery kit update!
Great information. I think I will give Liito Kala 18650 a try. My only concern is the longevity of the cells, but only way is to give it a try. 18650 cells also seem to be hard to source these days! Good to know there are reliable 18650 sources on Ali Express.
Just a warning, Liito Kala cells are also “faked” by other sellers since the brand has recognition. Posts on forums of Liito Kala branded cells not meeting discharge specs are all over, no way of knowing if they were actually from Liito Kala or some cleverly named Aliexpress store trying to pass themselves off as Liito Kala. Mica’s method here is without a doubt the best way to test cells since high discharge cells are much more expensive than low discharge cells so the only way scammers can profit off fakes is to use cells with a 5A discharge that are half the price.
Dunno about likolita. I heard they sometimes mix batches with fakes....kind of sad we have to deal with this situation of unreliable batteries
Be careful using any infrared camera for accurate temperature readings. Different materials and finished greatly impact accuracy. For example copper and aluminum fact as a mirror, you see you own reflection skin temperature or other not the object. Every matteriaa and it's specific finish has a specific emissivity factor that you you use to calculate the actual surface temperature of the material. There is a way to find and accurately calculate a mayterials emistivity so accurate temperature readings can be take. You can't rely in charts due to perceved finish issues, best to test.
A trick thermigraphers commonly use to aquire accurate infrared camera temperature readings is to stick some black electrical tape to whatever your measuring, it has a known emissivity eliminating innaccurat temperature reading issues with reflected heat, material differences and finsh differences to aquire very accurate infrared camera tempuratures.
The infrared camers temperature innaccuracte is the same for a $10,000 infrared camera or a $200 camera.
So when using an infrared camera it is best use to compare things to find heat issues not for accurate temperature reading unless you know the matteriaa being looked at emissivity and consider if the matteriaa acts like an infrared mirror so your seeing the temperature of some other matteriaa like your face. The art and science thermograohy can get complex for accurate measurements.
Have fun, be safe. Be aware that infrared camera temperature reading accuracy changes material type and it's finish, best to test to find it's actually emissivity or apply electrical tape to it for consistent accurate temperature readings.
agreed, plus how hot are your resistors getting during the test? their resistance changes as their temperature changes ( resistance is accurate only at 25 deg Cel ) one needs to typically use a resistor 4X's or higher the wattage calulated, and then it should be heat sunk as well. ( that's what those holes are for on those resistors ). not doing this will give incorrect voltage drop/current measurements. informative video nonetheless
I want to make up a replacement set of batteries for my electric skateboard, but the sheer number of 18650 cells that are available are overwhelming. With everything from 3500mah to 9900mah. What specs are important for electric personal vehicles? What do I need to look for specifically?
I checked the Liito-Kala website, but could see no free freight to New Zealand, shipping looked really expensive.
Under these circumstances I would say you are correct. I will feel good buying these batteries. Long term would be a good test.
Thank you for the video.
Great advice and good source of genuine battery cells.
how much solar would it take to power / charge a 48 volt e bike battery i'm just curious on the size for a solar home system
The resistors used for testing, what's the final resistance in them?
Good lesson. With all the batteries you buy, how do you ever have time to test them all individually?
I don't, unfortunately. But I do spot checks on random cells out of batches to get a good idea.
I'm hoping to build a 52v electric bike with the new kit. I would like to build at least a 4p pack. Will you have more size options available for the new kit? Also do you think that will reasonably fit on an ebike? I'm planning on a mid drive fat bike. Super excited to get started.
I agree with your test,always impressed by ur knowledge.Just a little example:you buy a bunch of cells from a Chinese supplier from any E-portal,and throughout that test u discover they are fake or not matching the quality declared by the seller.After contact the seller about the problem you won't have a penny back from them.This is a fact.Buy from sellers that are accredited and give u warranty,better with a physical shop,u get for what u pay.
Since you seem to be doing more individual cell testing, I would look at getting an icharger 3010b or one of the more expensive models to do discharge tests. You can actually graph the discharge curve and cell temperature with those chargers.
Hello. If you have to buy, for example, 130 cells to make a 13s10p configuration, once you test and detect that most of them are inferior, and you've already spent a lot of hard-earned money, you sense that there is a tremendous difficulty to get a decent battery.
fake crap bomb fire ,,, only good for vape using 1... using 130 is not good !!... . I would sell them off... dont use it maybe it will be okay but after 50-200 cycles you will notice very unbalance and not capable of continuous output stated (or remotely close even) than it is dangerous. Gotta buy genuine....
What did you use to add the timer to the video?
I’ve got two of your books. Only need this one for the win.
18650 Lithium Ion Battery Identification Reference
Each battery in this list has a picture, a description, a link to data sheets and relevant URLs, as well as brand/model/capacity/discharge rate/battery chemistry.
If you need to identify a battery cell this should be your starting point.
this is a PDF hosted on Google drive, you can view it from the page or download it to keep as reference.
drive.google.com/file/d/0B9KXttJ6nbz6VWUtcUtvZEY3dWc/view
Source: electricbike.com/forum/forum/knowledge-base/batteries-aa/27729-18650-lithium-ion-battery-identification-reference
My ebike cut off under heavy load. I can start again after just a short brake and I don't know if this is because of LVC (Low Voltage Cutoff) or that my BMS is faulty or that I'm just drawing to much current. This usually happens when my battery is getting down to around half capacity. I don't know where to start testing but I think it would be a good topic to investigate. How do I fix this?
Love your content, always useful and backed up with sources
Interesting... haven’t seen a lot of temp testing. I did just buy a liito-kala charger to be able to test more cells! Could you make a battery building video using mixed capacity recycled cells and maybe compare its performance on your bike! Great video!
When are you going to offer caps for other size cells like 26650?
Maybe not the most definitive test, but certainly something to consider when comparing cells to one another.
Hi where did you get the data sheet for the battery?
So, LiitoKala is a reseller of all brands of batteries?
Nice video thank's. How would you test 60 cells, I have a pack and some of cell are getting old (they don't charge anymore and have a very low voltage) And How can I be sure that the kepping cells are still good and are going to last some more years.
Maybe you addressed it somewhere else, but I'm confused over the 20 amps continuous comment on the samsung 25r. It's a 2.5 ah battery. at a 20 amp load, that would indicate 5 minutes or less to dead? I thought these batteries were .2C for charge / discharge? 2500mah * .2 = 500ma charge / discharge. Am I off?
batterybro.com/blogs/18650-wholesale-battery-reviews/30828867-is-it-a-fake-18650-battery-featuring-the-samsung-25r
look at the specifications...
2.5Ah so with 25A load max 6mins I think
standard charge 1.25A for 180min
Hooray! V2 soon!
Is the liitokala factory store actual litokala?
Do you think that you could get fake from liitokala?
For example when you buy one and you check it and it seems legit would you test others when you buy from them. I mean do you test all of them or just one from all.
If want to series 2 stack of 2*26650 parallel, and that each batteries is protected by a pcb, do I needa add a bms to the circuit?
I want to achieve ~7.4v and increase capacity over only 2*26650 series
Thanks
Hi Can i ask you something why are the nitecore battery and olight so expensive and are the better the LG Panasonic or Samsung cause those cost 5 Euro and Nitecore and olight around 25 euro
Should have done the test with one of those 4900mah gold cells, for sure it would have turned your testing gear to smoke :))
He plans on bringing them to market next year.
What suppliers do you use when going through Alibaba?
Will the liitokala 18650 & 26650 give a good life cycle.
why you dont have the digital version of yours books? I buy the DIY Solar Power, but i live in Portugal (Europe) takes a eternity to arrive . I whant to buy the ebike guide but if possible in digital version. Thanks
There are digital versions of them on Amazon, the kindle version. And amazon has a free kindle app in case you don't own a kindle.
can you send me the link, please? Thanks
Can't you take the wrap off. Should they not be lazer etched?
How many resistors needed for 5A and 10A discharge? Thanks
Do you know ohms law ?
@@MrSummitville The only I know was ohms in series will add and in parallel the total ohms will be divided. Can you help me?
@@jaysonhernandez6728 Ohms = Volts / Amps.
Therefore, 10 Amps = 3..6 volts / 0.36 Ohms.
@@MrSummitville Yeah I got i figure it out. Thanks!
I didn't even know they had fake batteries. you could take what I don't know and write a whole book about it
Do you have a video or what can I use to bulk discharge for storage of 18 650 batteries and have a Automatic cut off at 3.7 V. Thanks I just love all your videos very educational
hello i am waching your videos. i learned a lot. thanks.
i have one question as i plan to build my own bike battery.
why not using a balance charger like used for rc li battery packs charging instead of building a balancer into the pack?
thanks an regards
hartmut
A balance charger is definitely an option, but for ebikes it is less convenient because those chargers get expensive when going over 6s, requiring complicated charging of one pack broken into multiple parallel packs if you want to use an inexpensive charger.
thank you for the fast feedback.
you are right above 6s they get expensive.
Great info. Thanks yet again Micah.
Great video Micah! Btw I just finished reading your new book "ELECTRIC BIKE MANIFESTO". It was excellent like all of your books! Take care!
Aaron
I try to follow people who are battery geeks. It's not easy to sort it out, and there are economic interests who don't want DIY stuff to work. That's pretty much top to bottom the ebike industry in the US, retail side.
So right now I can follow the link to Liito Kala from your recent ebike review. There I find cells for $2 apiece if I simply buy ten cells. They say free shipping, and maybe it is legal shipping. I have 80 2200 cells I got from the Jehu/Tom thing last year. I've been checking them with the BT-C3400. You can pick that up during Ebay sales for a reasonable amount, and it makes checking the cells pretty effortless. Now I know precisely what the cells do, and that is reassuring.
You have a compression battery pack system. Gee, Jehu now has a compression battery pack system. You have links to batteries. Jehu has links to batteries. For years the purists rejected compression packs out of hand, but that was maybe because a lot of people wanted performance. If the springs can manage 3A and you have 3 parallel sets, a 36v battery can give you 350 watts or so. But no one is testing this out. There are projects. I have the Vruzend V1 and some cell holders like Jehu is using. The Jehu holders are very standard, "I've done this" kinds of deals. If you had a 30 cell battery pack built around that sort of cell holder (and it worked) it would be interesting. I really like the Titan 6s packs that can go together with XT60 series and parallel connectors, to make a bigger pack. But Trent is at $8 a cell, which is way too high, and he's marketing to RC users. A 6s pack is a good building block. You had that Maker system. Nothing ever goes very far, I guess, though Titan seems to be doing well with RC.
If I bought something like that little folder for $500, I'd want to be able to put together a $100 battery pack from something like what you or Jehu suggest/link. Any bike should be that 'hackable'. You don't say, on that bike.
There's a lack of energy in the ebike space. I guess there is more in the power wall space, but I'm not sure where that is going.
superb illustration😂😂👊👍
Sorry but I’m dumb hope you can include Fahrenheit in next video so I don’t have to do math lol
Good info Micah. Can you use LiFePO4 on skateboards?
Yes definitely. I believe boosted board uses LiFePO4
that's useful stuff man. Keep up with the good work. Cheers.
How do I test and existing triangle battery to see if it’s made out of fake cells?
Hey... I know this an older vid but I want to run a similar test. Do you have write up or link to amything on wiring the resistor setup u used? Its hard to tell from this vid how all the wiring is in your rig. Thanks
Simply wire the resisitors in parallel ...
Great Video, I like your presentations which are informative and interesting with props to boot. Good Job!!!
Nice Micah! You're my goto guy on all this batteries!
I like the improvised testing rig.
Very excited for the v2 caps. Now I need to start looking for a good 60 or 72 volt bms... any chance vruzend will start offering something like that?
Hey great video. The video on the NCR18650AU was great by the way.
Great videos & tutorials, thanks for the info! I’m planning on building a high-current battery pack using 30Q cells with a 20A discharge per parallel cell. I understand the most common nickel strips (7-10mm by 0.15mm) can only handle between 5 to 10 amps each. What would be your advice then? Multiple nickel strips on top of each other or maybe something else? Thanks!
I mean im a bit late, but 0.3 copper should be fine for everything
I bought 36v 8ah liito-kala battery pack from aliexpress, still waiting. I trust that it is good. Price was 68euros. I'l let you know when it arrives.
hello one more question.
i am thinking to conect a diy pack in paralell to my bosch classic battery pack.
do you have any experience about this?
Any way to tell if the Samsung batteries that you get in a pack are authentic?
My questions is that those battery work great for the price? I was thinking to buy new battery to build a power wall, this could be a great option? Thanks for your videos. BTW I’m a mechanical engineer like you.
Mayby the 18650 form Liitokala are fake. The 26650 flat top (black&Gold 5000mah) is topnotch.
Hello and happy new year.My question to you is how to determine c or is it s rating thanks Vince.
Are Liitokala supposed to be Samsung cells?
great video, in the middle of testing myself!!😊😊
Liitokala is Finnish and it means flying fish :D
I'm one % Finnish according to ancestry. Lol
Ihmettelin samaa. Onkohan joku Suomalainen keksiny firman tuolla jossain Kiinan maassa.
So the liitokala battery is original ?
Hi So this vid was posted a while back just wondering are u still happy with the batteries you purchased and shared a link to on AliExpress on, and do u still endorse them ,thinking of buying some ,but being a family man monies are tight so just looking for an update Cheers Gaz
Which battery, how many battery, what mah do u recomend to make 60v 30ah with 60a discharge for 60v 2000w hub.
The lesser battery the better😁
Better than LgMJ1 or just stick to LgMJ1.
I hate it when a video title suggest to see some honest testing and it turns out to be a time wasting long advertisement video
i went and looked at the v2 battery kit..... a true kit for a beginner would have all parts to build a battery, being new to this i don't know what i would need, but i am interested in trying it... i have been reading and working on my own solar system ..... i like the idea of the caps to build, I am not good at sodering .
Another well done video. Thanks sharing your experience.
I’m new to all this but trying to learn I love watching your videos you are a awesome teacher keep it up. So I have a few questions why do you use 18650 and not 26650 batteries? I want to make a battery for my boys razor four wheeler I want to upgrade the motor to a 36v 1000w motor. I’m just really confused on which batteries to use fo this any help would be awesome. Thank you!
Hi, Can you make a video about 48V 10 ah mini pack battery ? Thank you.
What is that power meter? Link?
Oops, forgot to include it in the links, thanks for the reminder! goo.gl/Uq6vPA
On the specs it says to work from 4.8v up to 60v but you are working down to 2.5v
Is it reliable? Does it have any battery?
Thanks for the video 😊
I always wondered on how tell fake cells from genuine cells.
Does anyone knows if Liitokala's Samsung 30Q cells are really genuine?
Litokala cells are purchased Direct from the Manufacturer so if you are outside of the US id Recommend them for any type of cell. I've bought some myself and they have all preformed to rating and spec
Pedro Teixeira
Chinese fakers do have wraps of ALL known brands, keep that in mind when deciding for a "brand".
They're probably genuine, but judging by some of the reviews they could be selling refurbished cells, so they might not have 100% of the original capacity or cycle life left. And that would be really hard to test, but it would explain their (seemingly) impossibly low prices.
Liitokala is also selling fake cells.
FAKE! Do not BUY! They have genuine Samsung picture, but what you get looks similar but it’s not! Just remove litokala sticker, and there is no Samsung inscription under. Also "+" cap is not the same as Samsung. Also, I have tested them on 10A. They cannot do it, voltage drops to 3V almost immediately. Again: DO NOT BUY.
Great Job Mikey
Ya I'm still kinda butt hurt about that April fools joke ...but its all good lol
Haha at least you took it well. Some people expressed their lack of pleasure with me ;-)
No pleasure here.... I'm trying to learn about batteries... you lost my trust.
I like your work Mike keep it up