spot welder

Are there any "snake pits" before i buy the first one i see.
What to look out for?
Nope i am not a fan of you tube, but i would like to hear your thoughts and experiences, please.
That i need one is for sure, soldering is nice but: sooooo time consuming with fuses.

So spot welders? any experience with brand or diy?...or what ever thought?

Thanks in advance, best Igor

Kweld is the best one out there for hobbyist, Malelectrics is ok too.
The cheap battery powered spot welders on ebay/Amazon are cheap from my experience.

Later floyd

Thanks Floyd,

Hmmm this will sit me back a other 200 euro incl shipping...
But the easy working with the niclel strips from battery hookup....
Need/want/would like to install/get ready ex ev cars a 200kwh ess....
Lot of cells...1400 of those 18650 cells at 2.7a is "just" 10kwh..at 80%dod..

With best regards Igor

So I will give you some advice that I probably would have ignored if I had received it since I like DIYing but maybe you can not repeat my mistakes. The short answer is get a Kweld.

The long answer is I first tried one of the cheap Amazon/Aliexpress spot welder circuits where you provide a battery and as seamed to be in about 50% of the reviews I blew up the mosfets($30). Next I tried making a DIY one with a car batterie and solenoid, worked from some YouTube guides. That one worked but was very hard to get consistent welds since the length of time was just how quick I clicked the momentary switch, and I would occasionally blow though the thinner walled cells which was a royal pain when you were most of the way though a pack and then had to figure out how to extract and replace that one cell. This setup cost me probably $200 since I already had a battery but bought extra parts as I iterated to try and get the results I needed. And then I got given one of the cheap AC powered Amazon/Aliexpress spot welders that usually go for about $200 and I thought my problems were finally solved. After trying to use it for the first time I couldn't get strong welds no matter the settings I used and all the cell packs I purchased from the fellow who gave me the spot welder were similarly poor weld strength. And now the grand finally I threw my hands in the air and bought a Kweld which I had found out awhile earlier was the best recommended one. I got mine from 18650 on Ebay, you can find out how to order elsewhere on this forum, and got a small battery to run it off of. My Kweld works amazingly producing strong consistent welds that are easily adjustable for the different thicknesses of nickel or fuse wire and I can several dozen welds before needing to let things cool for a few minutes which is plenty for a hobbyist who can putz on other things while waiting for the welder to cool as I make 100p7s packs. I was just too cheap to get the good solution and so spent as much or more only to have to buy it anyways.

Kweld period.
Read all about it.
Why mess with cheap junk when you can have the rolls royce of spot welders that will last you a lifetime.

Wolf

The maletrics is also a good one, I had the "version 1" I bought over 3 years ago and built several battery packs with it. The version 1 was very basic it only had one LED to show the power level, the new version has an OLED screen and shows much more info. Cost about 100 dollars for the welder itself, you have to buy the cables separate. I use it at about power level 50 (it goes to 99) so it has power to spare. The one I have runs off a 12 volt car battery, I been using a 27ah agm, and also a smaller 16ah odyssey agm, the new version of the welder can also run off a 3s lipo pack.

Which ever you get, its best to make your own probe cables with 6 gauge pure copper welding cables, for probe tips I build my own using copper nails. Pure copper wire will let you get good welds at the lower power settings. If the power settings are too high (70 or higher) the cables start getting hot, after 20 welds they will be too hot to handle.

On mine instead of a foot pedal or auto weld, I just put a momentary switch right by the probe tips, it works great.

@Wolf, thank you a lot again, it is really much appreciated, again, the same with all your comments and thought!

But reading(despite that awkward thread..jeez...the earth is really flat and corona was only to inject a chip in you...) and looking to several youtube videos i think i will stick with my 100w soldering iron.
some how i feel much more comfortable with it, just soldering 0.5a fuses to the cells without the risk to puncture a cell because it has thinner walls.
If YOU had a thread about the difference between solder and spot weld i would give it a other thought...
The only thing i can think of as a positive point is the time that is saved...that is it, sorry, i can not see myself comfortably spot weld 200kwh storage.
And 5 amps fuse per cell, is a little to much for my liking, i rather go with 0.5a per fuse per cell, and do the time consuming soldering job....yes i am very aware of lead poisoning...and i can tell you from experience and scientific point...you will NOT get it with soldering...
Keen weld is a very good, well thought piece of equipment, well worth the money, it is cheaper than those cheap ali express ali baba thingies or diy stuff.
But sorry i am not comfortable with that one punctured hole after doing a 10.000 cells.
It is NOT about the money, it is NOT about the learning curve(and fu** up 2000 good cells), no i am just not have a good feeling with it.
But sh** it would be a BIG time saver....and so easy, so quick and neat ect.

Thanks wolf but sorry i am afraid it is a nono for me, btw i am NO rolls fan, Cadillac all over!!!(have 7 old timersFrom 1949 to 1972 all coupe de ville and one Lincoln! mark 2)
Oke rolls: the fathom series..especially: 1932 v16, you can wake me up.

thanks and with best regards Igor

That would be the only rolls i like.....sorry

The fuse wire you have to solder no matter what. And I myself use to solder all my cells on my first 3 18650 batterypacks. But then I decided to make a 220ah lifepo4 batterypack with brand new 32650 cells, No matter how hard I tried I couldn't get the solder to stick on the new cells. Thats the only reason I got a spot welder.
Even on the 18650 cells, new or old you need to scuff up the cells with sandpaper to get a good solder. With the spotwelder you don't need to scuff up the cell, just remove as much of the old tab material and weld. That alone is a time saver. It can take hours to scuff up a box of cells.
As far as punching holes on the cells, that has never happened to me in hundreds of cells that I done, I always use the lowest power setting that gets the job done. When you use maximun power on every weld eventually you might punch a cell.
Once you use a spot welder for the first time, you will never go back to soldering. It makes the job so much easier especially on such a large battery pack that you are building. I got the 12 volt model because I don't like dealing with the high voltage plug in models.

100kwh-hunter said:

And 5 amps fuse per cell, is a little to much for my liking, i rather go with 0.5a per fuse per cell, and do the time consuming soldering job....yes i am very aware of lead poisoning...and i can tell you from experience and scientific point...you will NOT get it with soldering...
Keen weld is a very good, well thought piece of equipment, well worth the money, it is cheaper than those cheap ali express ali baba thingies or diy stuff.
But sorry i am not comfortable with that one punctured hole after doing a 10.000 cells.

Click to expand...

I completely understand and as I have said in previous posts spot-weld or solder it comes down to essentially your choice. There a thousands if not millions of cells that have been soldered and are working just fine. I choose to spot-weld as I have done enough testing some by accident and some on purpose of the 5A cell level fuse sheets and have found that if the cells are good quality they will most certainly pop the 5A strip. All of them. It is a cascading event as 1 fuse goes, amperage supply exponentially increases on the cells till the halfway point is reached and then goes down again till all of them pop. This of course is with a direct short across the pack. If 1 cell spontaneously shorts all the other batteries will dump into it blowing the 5A fuse again and not really affecting the others as the amperage is spread out among many. So as far as I am concerned I am very comfortable using the fuse sheets. I do however recommend good quality cells that have been vetted very thoroughly. By now I am sure you are aware of my cell harvesting and testing procedure and I leave nothing to chance only using the best of the best cells.

Additionally I also believe you know how I monitor my packs to the nth degree raising an eyebrow with even the smallest anomaly that shows up.
Sometimes I feel I have more sensors and backups to the backups than a small nuclear power plant. And indeed it is a power plant, self contained yes, but we all need to be responsible for our own safety and that of others who may be affected by an "accident". To avoid theses "accidents" a very close eye needs to be cast upon your power plant. More so than the union paid employees that monitor our grids. Most of which got a hack job because they knew someone.

So being a good steward of your powerplant is what I am getting at use the best cells don't say, well this one isn't so bad or this one's IR is just a little over, that cable will surely handle the load, you get my drift.

Solder away and as you have surely learned good solder is paramount including the speed. I have been soldering with 60/40 Rosin core since my early teens and have
not contracted lead poisoning yet. Ha my grandma and I in Austria used to melt it on the stove and poor it into cold water to see what cool shapes it would make. Plus the house I grew up in had lead pipes. Cold water only of course (we didn't have hot till later) and calcium rich water which coated the pipes. Oh yea back to Cadillac and Rolls.
I cut my automotive teeth at a caddy, olds (and have owned my share) dealership and later owned my own auto shop, repairing exclusive upper end european vehicles.... yea all of them including Rolls Royce all vintages.

Wolf

100kwh-hunter said:

That would be the only rolls i like.....sorry

Click to expand...

Yea but you need Alfred the chauffeur and definitely some gray poupon.

Since I could never see actually find someone who would sell the K-weld in the US.
I got the malectrics, and have been quite pleased with it.

jonyjoe505 said:

The fuse wire you have to solder no matter what.

Click to expand...

Why?
I welded up a 14S 160P battery using 32 AWG wire for my fuse and 30 AWG for the negative.

jonyjoe505 said:

No matter how hard I tried I couldn't get the solder to stick on the new cells

Click to expand...

Mine soldering iron is a 100w with a big fat tip, grinded into a small point.
One second per cell for the first solder, after that a second second "pushing" the wire in.
Never had a problem with it.
Not even when soldering the wire on 4x twisted 10 AWG wire, three seconds.
A old fashion, sorry brand is unknown, but has a wooden handle.

@Wolf
Your memory serves you good, if you would dig a little deeper, you would remember also that i used extensive testing(my fall out race) and it was thanks to you that i implemented the finishing touch, IR and bought the one you recommended, after all those you bought: the yr1035.

Dr. Dickie said:

I welded up a 14S 160P battery using 32 AWG wire for my fuse and 30 AWG for the negative.

Click to expand...

32 AWG is almost impossible to get here, for my neg side i use ~19 ~18 ish silver coated wire.
For the pos side i bought some???(5000+)fuses from ali express

Wolf said:

By now I am sure you are aware of my cell harvesting and testing procedure

Click to expand...

From the first cell you tested, i kept a close eye on you, we started almost at the same time if i am not mistaking...btw i am still waiting for your shipping container to arrive mr Spock....

with best regards Igor

100kwh-hunter said:

Mine soldering iron is a 100w with a big fat tip, grinded into a small point.
One second per cell for the first solder, after that a second second "pushing" the wire in.
Never had a problem with it.
Not even when soldering the wire on 4x twisted 10 AWG wire, three seconds.
A old fashion, sorry brand is unknown, but has a wooden handle.

@Wolf
Your memory serves you good, if you would dig a little deeper, you would remember also that i used extensive testing(my fall out race) and it was thanks to you that i implemented the finishing touch, IR and bought the one you recommended, after all those you bought: the yr1035.


32 AWG is almost impossible to get here, for my neg side i use ~19 ~18 ish silver coated wire.
For the pos side i bought some???(5000+)fuses from ali express



From the first cell you tested, i kept a close eye on you, we started almost at the same time if i am not mistaking...btw i am still waiting for your shipping container to arrive mr Spock....

with best regards Igor

Click to expand...

I was going to try the glass fuse thing (I have thousands and thousands of 0.5,1, 2, 5 amp fuses). But when it came down it, there just did not seem to be enough room to get them laid out in a manner which would work.
I got my wire off of e-bay (pretty sure), it is Remington if I remember.
They say they ship worldwide
32 Gauge Tinned Copper Bus Wire

@Dr. Dickie

I really had to dig in the archives, but in this thread you will find a picture of two 100p packs, you can enlarge the photo and see how i did it, i will try to dig in my laptop if i can find some better pictures.

With best regards Igor

Well that was a "quicky" it was in a folder called "ess"



With best regards

100kwh-hunter said:

Well that was a "quicky" it was in a folder called "ess"
View attachment 26056
View attachment 26057

With best regards

Click to expand...

Looks good, a better man than I

Ooof or should I say Wuff not liking those Sony cells in the pack. Especially if they are US18650GR series.

Wolf

Good morning all(cet),

Wolf said:

Ooof or should I say Wuff not liking those Sony cells in the pack. Especially if they are US18650GR series.

Click to expand...

?
it is possible that they are US18650GR.
They ended up in the wall because they could handle within time a charge and discharge of 1A (2x)
Did not heat up more than 10C from the ambient temperature.
Did not have a V drop more than 0.1 V after 3 weeks.
They did not have a bigger deviation than 10% of factory IR.
Where well within the mAh range of the rest of the pack.
SOH was above 90%
Fused with 1A fuses.

I believe that one of your circled cells has a IR of 41
But why don't you like them? Or should i ask: what could be/"or is" wrong with them?

With best regards Igor

Ps all my cells where tested on those specs, the first 1400 had a SOH above 80%