Can you solder 18650 batteries? Q&A#3

Where to buy a cheap spot welder for 18650 cells?
Source 1: goo.gl/ECP3kf (usually around $85)
Source 2: goo.gl/4a3a4U
Source 3: goo.gl/dA3kAS
Other parts that I use for building batteries:
18650 cells (Sanyo GA 3500mAh): goo.gl/J6ONJV
18650 cells (another Sanyo GA 3500mAh source): goo.gl/f10wHH
18650 cells (Samsung 26F 2600mAh): goo.gl/VhpP7T
18650 cells (Panasonic 18650B 3400mAh): goo.gl/fvwJZQ
18650 positive insulating washer: goo.gl/HBVOuc
Ebike battery cases: goo.gl/W2DLmE
Nickel strip: goo.gl/VIrNQq
Spot welder: goo.gl/KN3Uaw
BMSs: goo.gl/S6gSQx
Silicone wire: goo.gl/xmpbKD
Black 18650 cell spacers: goo.gl/hQxWF6
Large heat shrink tubing: goo.gl/6v1ow9
Small heat shrink tubing: goo.gl/OU3Z6u
Foam sheet for protecting battery: goo.gl/5e71tE
Kapton tape: goo.gl/D6BT57
Chargers: goo.gl/js0T0V
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Music credit: BenSounds

[@jehugarcia]

good vid. can you solder? - yes Will it damage? - yes How much damage? - No one knows The common claims Ive personally tested have mostly resulted in less dramatic results than popularly believed. The over charging damage in LifePo4 = Not as drastic as everyone says it is The degradation in storing Fully charged cells = Not as drastic as everyone says it is So I agree with you, Not ideal for cells but should you do it? its fine if you are quick but mostly its up to you, if you feel comfortable doing it, if do not need your pack built the best possible way, I say Go for it.

[@10OZDuster]

Jehu did you buy a spot welder already? if you did which one and do you recommend one thanks

[@cutty02]

Sony says apply heat for 1 second or less.

[@itevensystems8860]

There is more damage from your terrible thinking than from soldering battery cells. If you dont have skills to do it professionally, then dont do anythink, just sit at watch. Using your brainless logic I can prove this: soldering ANYTHING will damage your lungs, as you inhale the bad smoke. How big damage? : no one knows. Conclusion: we should never solder anything, right? Do you see my point how useless is your thinking process?

[@comictrio]

I came up with a simple technique for soldering the strips to the 18650 batteries that limits the amount of heat to the battery and provides a solid solder connection. I cut off the sharp corners of the strip and then I cut a small v-notch on the end of the strip. I put a small dot of liquid flux on the battery pad and a small drop on the v-notch on the strip, then I add solder to the tip and press the soldering iron tip to the v-notch on the battery. Done properly you won't have to add extra solder, just the amount added to the soldering iron tip is all you need. The flux makes the solder wet out into a small puddle and it takes about a half second, with a hot iron, to create a proper solder connection with very little heat transfer to the battery.

[@robertklaiber9562]

diagram!

[@jymjym777]

->

[@beerborn]

Dude ! I'm an electronics technician and I have a Canon 5D Mk IV camera that uses LP-E6 batteries which have (2) 18500 batteries incased inside a plastic container. When the LP-E6 battery no longer hold the charge, I open the case to remove the two 18500 batteries and replace them with fresh one's. Yes, I solder the two 18500 batteries together and put them back in the case. The trick is to use two soldering tips to solder fast without spending too much time soldering the battery that could damage it with only one soldering tip. If I bought a brand new LP-E6 battery it would cost me over $30 but if I buy just the two 18500 batteries to rebuild, it would only cost me only $8. It's cheaper to buy two soldering tips and solder them yourself.

[@Greywolf74]

If youre going to solder cells you need to sand or scuff the surface of the battery, tin your battery strip with a generous pool of solder, coat the sanded surface of the cell with flux, and then Apply your soldering iron to the battery strip in order to melt the solder onto the battery. This way you arent adding additional heat to the cell by tinning it and you arent applying your iron directly to the cell. If you do it properly you wont need to heat the battery stip for more than about 3 to 4 seconds and very little heat actually reaches the cell.

[@TimFelbinger]

Would love to see that video that tests how much of a difference soldering actually makes.

[@mattcousins1707]

Bump

[@gefiltafish2187]

Bump

[@technocrat7971]

I use 5mm x 0.2mm Pre tinned copper Tabbing Bus Bar Wire/Ribbon. Its used for connecting solar cells but it's perfect for soldering battery packs it sticks so much easier than nickel or copper wire. You can find it on ebay for around $5 for 4 metres

[@oz93666]

I'm not convinced soldering is bad ... solder melts at 180*C.... what would be the temperature by the time the heat is conducted inside the cell??? perhaps a small fraction of the electrolyte might be 100*C for a few secs .... 18650's in surgical equipment are routinely sterilized at 120*C for 15mins with no ill effect !! Yes the cells are heated to this temperature!

[@artieryan5084]

Thats kinda how i feel too. But i work with second life batteries so i care a bit less

[@Ihaveausernametoo]

Yes heat damages them but it's perfectly doable to solder in just a second or so with a temperature controlled one (more power and compensates for it when the iron touches a heat-sink like a battery) and leaded solder. Fine sand-paper first. Not the slightest bit warm afterwards, no problem. Put some solder on the tip right before so it transfers the heat quicker.

[@brianmuehlher5330]

Thank you for being straight forward with your information. I want to make my 18650 batteries button tops for the lack of a better term (solder a small nut to the + end). Now I feel I can do this with confidence. Thanks again!

[@EvolvedBicycles]

Just an idea, could you cool the cells in a fridge before soldering so you are limiting the heat rise?

[@jimhal5553]

That may cause you more problems. You will still have to get the solder point hot enough to allow the solder to adhere. The temperature difference between that point and the rest of the battery would be a good deal more than room temperature battery. That and you will be heating a much longer time. Bad idea.

[@artieryan5084]

Good thought

[@Fungineers]

Solder in a fridge

[@walterblanc9708]

Never soldered to new 18650 only repurposed. This is how I do it. Use Thickish cable. Cut back the insulation a bit more than normal, Solder the exposed end completely infact saturate it so you s blob on it. Trim end as flat as you can. Clean the battery terminal as best you can. I imagine roughing it up will help but I have not done that. position battery vertically and bring wire perpendicular to the terminal but do not touch. using a hotter soldering Iron than normal heat up the wire quite high up the wire say 1/2 inch add a bit of solder. the solder will flow by gravity and just as the big blob gets to the end touch it to the battery terminal. Ok the wire is at a bit of an awkward angle for saving space but it works for me. Same rules on a smaller scale apply for repurposing old Phone batteries, Maybe it does knock a few charge cycles off, never noticed, don't care. Yes I know its not the way you're taught to solder and yes you might need to practise a bit, but so far any joints I have been happy with have not let me down.

[@circletech7745]

I consider soldering 18650 cells like a person smoking. In theory it is damaging but if done only briefly, the damage is minimal and the cost savings over using a spot welder is worth it if you are like most of us DIY ebikers and are only making one to two packs. I have two 12S battery packs. One 12S4P pack made of LG MJ1 cells and a 12S8P pack made of Samsung 28A cells from overstock laptop battery packs. Both packs are soldered with solid-core 14AWG wire and have been performing great for months.

[@heyeveryoneimcool]

Problem I had was the battery body acts as a heatsink and just spreads the flux all over the terminal so I had to pump the heat up a bit and use a chisel shape tip as suggested here. Thanks for that suggestion.

[@atomicskull6405]

Yeah if you try to solder with a typical 70w soldering station you're going to have problems. If you have a 120W or 150W high output station though that's a totally different story those typically use high frequency induction heating (low voltage high frequency AC running through a coil in the handset) instead of thermal heating and can tin and solder an 18650 cell in 1-2 seconds tops. They are also GREAT for soldering large battery connectors. Two units to look at are the Xytronic LF3200 and the Atten AT315 (they both use the same tips btw)

[@dmac2776]

can it be possibly better to solder the negative tab to the side and cover with heat shrink or tape so not to heat the end up?

[@jaredbrandt9602]

Heating the electrolyte is an issue but not really if soldered properly. Destroying the blowout vent is the issue, which is quite sensitive.

[@FIGUEIRINHA]

nickel are the most used. why not use copper wire? 4mm copper can handle 28A and 6mm can handle 36A.

[@robertfitzgerald3432]

My problem question is a rejuvenated 18650, Samsung..POS cap pulled and inner pushed to bring the batt from Zero back to 3.74 VDC. Meaning the meat -- lithium just below. Can I solder on the center of the safety button since I depressed it back into contact with the stem?

[@the.reel.mccoy.]

I am confused. If you solder the piece quickly enough, such as beading a bit of solder on the iron and letting it drip onto the 18650, wouldn't it not heat up much? All of the spot welders I've seen or heard of still end up heating the batteries quite a bit. I'm not trying to act like I'm the best at soldering or anything, but it's so quick I can typically touch it soon after and it's already cool. I keep old computer fans on mine, maybe that helps a tiny bit, I am honestly very unsure.

[@usertogo]

If you solder why would you use Nickel when Copper has several times better conductivity and is cheaper too! Now if you could find out how to spot weld copper, that would be golden! What do Tesla batteries use? Nickel? Sounds like you need a free batterie heating system?

[@neutronpcxt372]

This is something that's been bothering me for a long time too. Perhaps it's tensile strength or something else.

[@aleemmohammed9977]

Well if you shouldn’t solder them then what can you do?

[@artieryan5084]

My first test on a bad battery doing one side at a time. After i was done with the neg terminal i checked with a thermal gun and got little over 100 degrees. And thats with having trouble... just a tip for the diy

[@yougolook]

I’ve obtained several battery packs that are made of 32 cells. 8s4p. They are 26650 cells And are LiFe PO4. There are no Bms boards. Only. Red and black leads. They are are Reading about 26.3 volts. Label says 12.8 Ah. Question: How can I best use these? Test them? Charge them? There are many... A pallet full. Each pack about the Size and weight of a brick... they are shrink wrapped.

[@E-BikingAdventures]

Why use nickel? It's only 22% as conductive as copper and twice as expensive.

[@pascualclaudio5707]

Hi! great vídeo, I just bought a bunch of 18650, do I really need a bms and, how can I get a free copy of your Ebike guide if I live in México?

[@keithrobinson870]

not sure what happened there looked at my screen showed it complete when I posted the comment it deleted the middle portion of the comment so here goes again put the cells in your freezer for 15 or 20 minutes that should lower the temperature enough that you can solder to them and you'll have a little more time to work with it heavily tin your soldering tip put so much solder on it that it's ready to drip off then let that drip land on the cell then solder onto the solder it makes it a little easier it gives you a little bit of cushioning there and your tab will be soldered underneath and on top which will actually work the solder has to be there anyway but at least if the cell surface is cool when you place it there odds are you won't damage anything at the very least it'll give you a couple more seconds of working before it reaches a temperature that would damage the cell, what I'd like to see is some research done to show us exactly what temperature damages the cell

[@kennysanti6557]

Do they have to be drained of charge before soldering? As iv a loose tab on my m365 battery

[@caragon2]

Can you spot weld nickel strips to 18650 batteries with protected button? I am creating a battery pack with 4 18650 batteries and spot welding in parallel.

[@MrGiodude17]

Did u do the comparison vid

[@njfulwider5]

What do you think about using Recycled Cell phone batteries for projects. I have made a few 3S 12.6V"balance cables" battery packs, but I have not gone over that. I also leave the protection circuit on. I feel more comfortable soldering this way. I tried taking one off and it was a disaster. But I am a newbie to DIY. Would love to make some 5s-6s cells and use in projects also. Just not sure how far we can push them. I normally find older cells with 80-90% capacity left over. Samsung seem to work the best. Couldn't find any info on them used above 3S. Any Thoughts? I know these are not 18650's, But I see so many cells going to waste and I really think these can be revised. The space they take up is so small, you can use them almost anywhere.

[@rajeevranjan7644]

Hi how to make a proper battery configuration for home inverter with 18650 cells ? If I make 3s configuration the potential at full charge would be 12.6V which is happily accepted by a 12V inverter system but the over discharge protection system of the inverter would kick in when the potential diff is around 10.5V leaving a major chunk of energy left unused as these cells are said to be discharged when they hit 3v i.e. 9v in the configuration. Any suggestion is appreciated...

[@gwizz7804]

I have a question, how about using a conductive adhesive instead of soldering, welding or the vruzend things?

[@ntag411]

Soldering on any can type battery is probably not good. Many moons ago I soldered nicad cells for a cordless phone. The batteries worked but only a fraction of the life of the previous cells that were tack welded.

[@nanettebarling1222]

I was wondering if some kind of "fence" could be used. Could even be a wet rag or something to block the heat travel? Idk. Anyway, is there 18650s that have "nubs" so they can be used stacked? Help! Lol

[@savvasberdos1828]

Hi, is there any specific configuration for the dimensions of the nickel strips in relation with the battery capacity. Meaning the amount of electricity that goes through the nickel strips. For example a greater capacity or voltage requires thicker nickel strips?

[@atulpandey3739]

I'm building an electric scooter with a 1000 watt motor and for the battery pack I have 150 18650 cells what I want to ask is how to connect cells in series and parallel like I have seen in some packs few cells have cathode on the upper side and few have cathode on the lower side why do we change the position?

[@georgelewisray]

Great !!, very important and timely topic. thanks much.

[@PecanPie1102]

Is there a cheaper generic version of The Bosch 36 volt charger for active line ($200) (and end plug) and the expensive 400/500 battery ($800-1000) omg in 120 volt,USA .

[@EbikeSchool]

I'm not sure what connector the Bosch charger uses, but this is my go-to source for chargers: goo.gl/js0T0V Just choose the one with the correct voltage and if they don't have the right connector then you'll just have to swap the connector yourself. I have a video on how to add a charger connector.

[@azimalif266]

Please make a video on what's the efficient way to charge lithium cells from solar without converting to AC then DC. What's the most direct way to charge cells from solar (without damage)?

[@EbikeSchool]

I did, check my recent videos for solar

[@GoldenSim27]

they should just make cells with little screw on both sides like the headwaybatteries but miniaturized li-ion version

[@RonYason]

Does it have to be charged or discharged when you solder cells specially when it's a recycled one?

[@danielhawkins6619]

eh bro, went to website,forgot (stupid) password, did NOT receive password reset email,.....why do I have to "login"??,...wtf?. so,...I can't even "browse " your website TOTALLY frustrating!!

[@Bigdaddysteve48]

I have a vape and the circuit board inside wet bad so I tool out the battery and cut the wires, now I need to solder them to the head on top were they screw into the battery compartment, what solder do I use for this. Please.6-11-18@ 1:00AM

[@TheFarleyGordon]

I can concur Magic Mike. are 8-track tape machine still around neither will the 18 650 Tesla has even moved on the solid-state lithium battery is ramping up for production

[@mikegovorushkin]

can you make a how to solder video i know there are lots already but i still cant get it to work well

[@TheNamelessSir]

Dumb question. What about 2170 cells? The ones that Tesla Motors is starting to use. Will they work okay for an ebike, are they cost effective, how difficult are they to acquire? Also, how big would a 1kWh pack be? I just want to be able to say that my bike is a Tesla.

[@EbikeSchool]

Yea, those cells would probably be great. The problem is that they aren't publicly available yet so not only do we not know their exact specs, but we can't build anything with them yet. But you can rest assured that as soon as they are available, you'll see ebikers messing around with them :-)

[@geebonzo]

On the Kickstarter people were going to solder on the pre-welded strips. Has your thinking changed on that? Why doesn't somebody just sell different cells and have a robotic spot welder in the same facility to put together whatever people want? Why do we end up with all this stuff coming from Asia? Once you have robotic welders, what is the point of doing this DIY? Juiced touts the fact in their Hyper Fat that the pack is made by a robot. What the heck. I put together an ebike battery with Titan Flight modules. Their modules include a 6s, Sanyo GA cells. So I use 4 (24 cells) with 2 series and then 1 parallel connector. It's a nice low capacity battery pack, certainly good enough as a reserve. I figure Hobby King will start to sell 18650 groups with the standard RC balance leads and connector. The RC chargers give a lot more information, anyway. I can parallel charge as two groups. For $10 I can buy a gadget that shows the charge in each cell. None of this is available with ebike configurations. People don't know how well their packs remain balanced. I give you credit because the entrenched ebike industry wants people to understand as little as possible. No watt meters, no watt hour meters, no cell information, no settings for the charge %. If you solder people will jump down your throat and if you use hot melt glue they will jump down your throat. It's kind of idiotic to own a spot welder for individual use. But yeah, you shouldn't solder, but why do people need to weld? My money is on RC packs made from good 18650 cells, or maybe Shawn McCarty's mechanical system.

[@EbikeSchool]

Soldering on the nickel once it is already spot welded is fine, as long as you do it fairly quickly. You don't want to heat it for a long time, but since you aren't directly heating the cell terminal, you can heat the nickel for a few seconds without much heat transfer to the cell itself. Hopefully we'll see more packs like you are talking about become available soon!

[@novelentertainment5285]

can you make video of fusible link and circuit breaker in battery pack?

[@terfayuhe2462]

can you use a copper strip instead of a nickel trip to solder a battery pack for laptop?

[@altamimi2008]

Hi Micah, can you make video about " sentinel wheel e-bike" please ? Best greetings,

[@Dinco422]

2:09 uhm... cathode is negative not positive :)

[@conradsinsua7415]

can you refrigerate the batteries then solder them?

[@commanderoof4578]

Grab soldering iron melt solder dab it onto the cell. Then get wire place on now cold solder and heat solder only then done. DO NOT HEAT THE CELL!!!

[@robertcartier5088]

A question on iron tip size: 1) small tip + longer time = soldering temp reached (solder melts on battery contact) 2) large tip + shorter time = soldering temp reached (solder melts on battery contact) In both instances the battery contact must reach the same temperature to be able to melt the solder onto it. There appears to be NO difference in the temperature reaching the chemicals inside the cell through the battery contact being soldered. Is the fact that the temperature is reached faster or slower significant if the total thermal energy transferred to the interior is the same in the end?

[@robertcartier5088]

Never mind, I figured out the flaw in my logic. lol If the damage occurs at less than 100% "soldering temp", the time it takes the smaller tip to reach soldering temp is longer and therefore "damage temp" is experienced for a longer time inside the cell. OK, larger tip it is! ;-)

[@EbikeSchool]

Yes, look up heat flux

[@net200777]

sup man. I see a 1500w kit on aliexpress for like 200$ I think it was. Can you do a tutorial start to finish on a build your own style project with spending the least amount in mind while maximizing performance and quality?

[@manishmaurya414]

can u talk to me about how to increase speed for 48v ebike plz sir

[@thomasholland4313]

what about conductive glue

[@EbikeSchool]

I've never tried it for 18650's but that'd be an interesting test!

[@oz93666]

no good ... this is epoxy with metal powder added , has a resistance approx 1000 times that of copper OK for led's with currents in the mA range ...

[@anthonyfenn8136]

It wont hurt em be quick if u mess up let it cool... No freezer

[@naseebdangi3140]

My Qn is: Is there any way for connection of two batteries without soldering so there is not such consequences?

[@hatschmolo2923]

just use some kind of plug/connector. If you want to permanent connect two batterypacks you can spotweld

[@devwatts]

Can the bms charge each cell in the pack because The bms cuts off the charge when even a single cell reaches 4.2 to prevent overcharge.

[@EbikeSchool]

The BMS doesn't actually charge the cells. In fact, it does the opposite. It's like a floodgate opening on the cells that reach full charge first. It slightly discharges them to allow the other cells to catch up, that way they all reach 4.2 V together.

[@LukeVibert1]

How do you confirm the quality of the BMS that you use? From other people's videos I have heard of BMS failures.

[@AveragePlayer1_PS5]

Hi, thank you for making great videos. Q: How do I know what volt and amp hour my battery pack will be? For example I want to build a 36v 20ah battery!

[@EbikeSchool]

Well that one is easy. A 36V 20Ah battery is 36 volts and 26 amp hours :-) ...But I assume that's not what you meant. To calculate how many batteries you need, multiply by their nominal voltage and capacity ratings. For example, if you built a battery using li-ion cells (which are 3.6 or 3.7 V nominal) that were 2.6 Ah each, you'd need 10 cells in series and 10 cells in parallel to get 36V 20Ah, requiring a total of 100 cells.

[@AveragePlayer1_PS5]

EbikeSchool.com that's great. Thanks for the reply.

[@user-uz2bk1hs4c]

If I want 48v 40ah what bms will support this?

[@craigsj]

Spot welding also heats up cells as does soldering nickle tabs onto tabs already welded to a cell, a technique this guy endorses and demonstrates in other videos. Also, use of a conductive iron is not the only way to solder, application of current can also do it just like that used for welding. The advantage of resistance soldering is much more limited and confined application of heat. Resistance soldering also has a big advantage over spot welding of allowing you to use copper rather than nickel and, done properly, does not present a problem with heat. Sadly, none of this is discussed by this self-proclaimed "professional". I suspect the "scientific community" knows very well how heat damages cells, you just are part of that community, Micah.

[@EbikeSchool]

I believe you meant to say that I am "not" part of that community.

[@craigsj]

I believe you are right on that. How heat degrades a battery is more a concern of engineers, not scientists, and you won't find engineers publishing scientific papers to educate their competition on such issues. You can count on it being well understood by people who need to know and *actually* work in the field, not just blog and youtube about it. Spot welding is done because it is cheap, fast, and automation-friendly, not because soldering destroys cells.

[@hanoverview]

i just did a 2S 8P ... god this is a pain in the ass !

[@easyamp123]

all true, good stuff

[@atorresmiguez]

Hello, thanks for your videos, they are very useful. I want to put a switch in the box of my 10s battery pack, can you give me any advice? sorry for my english and thanks in advance.

[@EbikeSchool]

You can find switches rated for 20A-40A, but a switchable circuit breaker or a relay might be better and easier to source. Search a little about both options and you'll find examples of people using each.

[@timwatson7948]

Your right

[@user-xr6wt8lo6e]

i just want to know..i see some people that build batteries used fues to protect from over lode did it really matter? sorry for the bad English :)

[@EbikeSchool]

Your english is just fine. Cell fuses aren't meant to protect against normal overload, they are meant to cut off a cell from the rest of the pack if it shorts and could draw enough power to overheat. Cell-level fuses are usually used when a) you have a large battery that could be dangerous, like an electric car, or b) when you are using low quality cells, like the DIY powerwall people. If you use high quality cells, you shouldn't have an issue with any cell shorting. But if people's lives are at risk, or you use crappy cells, then cell level fuses are a good safety measure. Toda al hashe'ala.

[@i80386sx]

It's like deep frying a shirt. You can but you really shouldn't.

[@dudeskidaddy]

Do several set ups using different solder tips too. The idea that a big solder tip is better than a small one while sounding logical is also just hearsay.

[@cesargrimm]

I'd love a vid about the comparison

[@EbikeSchool]

I'm working on it. It will take a while but it's one of my projects :-)

[@LoweWetterstrand]

Before you get started, please share how you're going to do it with us over at /r/18650masterrace. The general consensus over there seems to be that soldering cells is dangerous, but I'm sure they could still give you some pointers to make the tests more "scientifical."

[@EbikeSchool]

Thanks for the tip, Lowe. I'll share the methods over there and ask for advice.

[@Fungineers]

I solder in a fridge

[@norxcontacts]

Do you know of any 120 volt spot welders?

[@EbikeSchool]

goo.gl/GJgqrv This one, but just double check with the vendor that they send you the 110V version and not the 220V version.

[@dudeskidaddy]

So much hearsay when it comes to batteries. Yes please do the test and show data. Thanks!

[@user-rx4vs3kk4i]

Nonsense just look at the german dudes test. I personally used a blow torch to lockm down the nickel strip for my parallel groups because I bought the wrong nickel strip and my hobby welder can take it. Months later I decide tht he capacity differences evn with aa caacative active balancer didnt feel safe so i took it apart and retested the cells. After BLOWTORCHING them down sometimes holding the flames on for 5 or more seconds there was no loss in capacity. I though I ha ruined them but no. They were basically the exact same before torching. And my thermal imager backed up my caacity readings after testing, They are alot hardier tehen you guys make them out to be. BUT hold on I have had 2 thermal runaway events I want to tell you how it happened to save you the same nightmare. Make sure NO strands of anything electrically conductive slip underneath the top protective coating, it causess a short that doesnt stop heating. The other was when I held a solding iron on tthe battery for too long and it gassed out. IIf you have a thermal runaway get that part of the pack under running cold water immediately. If it means putting the whole damm pack into the toilet do it. Because if you dont i can assure you will regret it.

[@Denvermorgan2000]

I think I'm going to buy one of these i really want to make my own battery.

[@LukeVibert1]

Can you do a review of spot welders? I bought the Sunkko 709A because it has the welder leads but the performance is lacking. With everything maxed out it still doesn't make a good weld. The design of may battery doesn't allow for welding parallel groups like you do.

[@zigmass4899]

😃😃😃

[@fookutube501]

Hi,can i use 2 different 18650 together?....I have 2 different brand of 18650,but both are 2000 mah..Awesome video keep it up!

[@colinmorand129]

It's a Wide tip not a fat tip

[@paps69shed]

Come on guys. if you got the dosh to spend on the Samsung 3000mah sets then get yourselves the best smart bms and get a mini spot welder. Better still if you got that kind of money just buy a readymade battery. For the rest of us just doing up an old mountain bike for fun, fuck it! solder away on those old laptop batts. Be quick with your iron and do a nice job, let me tell you '20 miles ridin' on a cheapo homebrew will give you more joy than 30 miles on a battery you had to re mortgage the house to buy.'

[@PowerThrough2011]

can I purchase the book?

[@EbikeSchool]

It's only available for purchase as a downloadable ebook at www.UltimateEbikeEbook.com right now. I only have a few paperbacks left but I'm working on getting a new production run of paperbacks that will be available on Amazon. That's probably a couple months away though.

[@LukeVibert1]

Can you publish it on Amazon? I am interested in a paperback too.

[@EbikeSchool]

Working on it, Luke. I'll post a video when it's up there so people can find it :-)

[@DD-dq8pp]

Big fat hot tip lol

[@blabnfriends]

Dont breathe what? You arent vaporizing lead with a soldering iron.... that would hurt so fucking much...

[@TheKetsa]

Yes, you can...

[@JesseWright68]

Let's see some empirical evidence that soldering is damaging when done properly.

[@JeffBourke]

Title should be "SHOULD YOU SOLDER 18650 CELLS"

[@cutty02]

You should have mentioned that some manufactures used to recommend a 1 sec solder technique. Seems like you didn't really do any research and just regurgitated the common rumor

[@danielhughes6896]

Surely this is a very easy test to do (a least capacity wise) just solder a cell then do a capacity check, all this "no one knows" crap is meaningless. AveRage joe has several video's where he pull cells out of his pack (that have been soldered, and then heated again to remove them from the pack) to check there capacity and guess what, no loss of capacity, from this *double* soldering.

[@AB-cr5fl]

....just the tip

[@whatthefunction9140]

I think this needs an experiment

[@EbikeSchool]

I'm working on the experimental setup. I'll let you guys know when its ready! :-)

[@v10moped]

"Professional opinion" based on everything he read on lithium cells. Nevermind. I rather get an opinion from someone with ACTUAL experience.

[@rcairman2]

How to solder perfectly 18650 in less than 1.5 seconds: kzbin.info/www/bejne/bmq3Ypipg691o6s

[@jpjay1584]

hahaaahaa!!! you just said 10 seconds!!! are you crazy??? NEVER let the soldering iron touch for 10 seconds!! and next you say 10% or 5% less capacity. 10 seconds is enough to do huge damage.

[@FynbosGarden]

Sorry as You are trying. But.. Do the test you suggested. Then you become an authority . Until then you cruise with the best of youtube woffle takers

[@ConorFenlon]

Should people listen to music at a level that'll damage their hearing? No. Will it definitely damage their hearing? Yes. How much? Who knows?