Modifying prebuilt junk, in stages, to be less junk like.

DIY Builds
828

Yeehaw, some Gen U wine Wintonic e2200 cells, from 2017, with a max 6.6 amp max discharge current.

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They ran my laptop for 20minutes. It Said ~56% when it just shut off, no warning.

edit
These Wintonic cells are not going to be great for test welds. The center of the anode has a raised portion in the center, which was then compressed by the spot welder used in china 8 years ago. The can was then easily deformed when removing the weakly spot welded 0.1mm nickel plated steel series/parallel connections.

Cells 1&2 were in parallel, 3&4, and 5&6.

cells 3 and 4 registered 3.5559, and 3.5594
cells 1 and 2 were 3.6129 and 3.6113
cells 5 and 6 were 3.6163 and 3.6164

I ran cells 1, 2 and 3 in a 3S 18650 leaf spring holder, powering a 12v variable speed fan.

Cell 3 hit 2.8v first, triggering the LVD. Cells 1 and 2 were 3.48v and 3.49v under a 1 amp load

Same test with cells 4,5 and 6.
Cell 4 hit 2.8 first again and 5 and 6 were 3.44 and 3.45.

Cells 3 and 4 were in the middle, in parallel, and have the most dented cans.

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Iā€™m gonna run them all way down and test weld on them anyway, but I suspect the cans are far thinner than my Eve 40PLā€™s or BAK 45D, and not great for refining the settings on those cells, but they have to be better than using razor blades just to determine the general power and pressure required with the P20B welder amd 0.2mm copper.

Looks easy enough to rebuild the Laptop battery with 6 Eve 35Vā€™s

1 Like
829

Hmmmā€¦ those awithz welders sure are intriguing.

With the way the cell market is looking, welding copper is going to be a must-have feature for spot welders moving forward and these welders seem to have what it takesā€¦

My curiosity is not quite at the ā€˜buy nowā€™ level, but I have to admit, itā€™s pretty damn close

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830

I like how AwithZ have so many different models with increasing power levels, and of course prices.

Iā€™m hoping they prove durable.

My P20B, 14.6kW model came with 3 sets of replaceable copper alloy tips, and high power levels do wear them pretty quickly.

I want to weld a button onto my JP30, and the tips were a bit too fat. I busted out a new set which made the wear obvious.

More replacement tips are available and are apparently far less expensive than replacement tips for the Glitters.

I was thinking of starting a dedicated spot welder/copper nickel sandwich thread.

The copper welding flux/ brazing paste lowering the power required to successfully weld 0.2copper and 0.1 nickel plated steel, probably means most welders would benefit from using it, though I have not used it on just pure nickel.

Frankly, I donā€™t see myself ever using anything but copper, and nickel plated steel sandwich, even on low powered batteries.

I want to exeriment with different thicknesses of NPS, and perhaps stainless steel which has more resistance and welds hotter. Nelvick says he tried it and it sticks to the electrodes a lot more.

The adjustable duration preheating function, single/double/triple pulse and the intervaL between those pulses is a lot of variables to play with.

I got to say I really love the foot pedal after my cheapo purple welderā€™s set delay where I felt rushed and anxious. I nearly blew a hole in a BAK45D can when it fired after the probe slipped.

Iā€™ll try and relieve any and all of their curiosity regarding the AwithZ p20B spot welder.

I didnā€™t see a dedicated spot welding thread.
Hiding info in a TLDR ā€™ junkā€™ thread is not helpful and limits feedback.
Not sure which category such a thread should be placed within.

2 Likes
831

Iā€™d probably put it in esk8 electronics / new tech and development. Although the content itself is definitely more important than where it is located.

This new wave of tabless, super powerful cells has me wondering how many people in Aus are actually capable of building a pack that isnā€™t bottle necked by the construction of the pack itselfā€¦

And whether it would be worth my while to come out of retirementā€¦ with welders like this that seemingly make it easy to weld copper, I not only want to experiment for myself, but believe I could definitely be of service to others in need as wellā€¦

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832

There is no money in esk8. If youā€™re doing it for passion, then rock on.

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833

Oh for sure. Preaching to the choir there.

Definitely for the love, but it can self sustain.

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834

I have a lot of money in esk8ā€¦

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836

Pretty sure a Kweld and a good weld battery can do 0.1 copper, 0.1 nickel.plated steel sandwich.
My 21$ purple spot welder could with a cheap 5.2ah Zee lipo. I built 3 esk8 batteries with it.

The welding flux/brazing paste would.probably allow 0.15mm copper.

The nickel plated steel is better for sandwich welding, and the strength of steel when tearing off the welds is noticeable.

0.15mm copper should be electrically equivalent to 0.6mm pure nickel, and rolled sheets of copper is cheaper than pure nickel.

My lower back is not cooperating.
Today was again too hot outside.
Fiona got a bath and a haircut.

The Wintonic 18650ā€™s are all in parallel on a 10 ohm 100 watt resistor, and read 0.0922v. I want to play with the Awithz welder, but itā€™s not happening tonight.

837

Yeah I canā€™t be arsed with sandwiches.

I think iā€™ll just go baller and get this bad boy. 0.2mm copper direct to cells, no flux, no sandwich.

3 Likes
838

That is a beast of a welder.

Nelvick has welded 0.6mm copper with it.

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839

Holy crap, that is crazy. Honestly wasnā€™t following the new welders but now im probably gonna sell my kweld. Whatā€™s the smallest awithz welder that will raw dog .2 copper? I donā€™t mind if it gets warm as long as itā€™s consistent and not gona shit the bed if i do up a pack or two.

I kinda feel like .2 is the thinest copper that would be strong enough to withstand the same abuse as the nickel i use. Was playing with some copper shim stock and even .15 is just a little too weak even if it would have plenty of conductivity

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840

I feel like the pack construction should be taking this into account and stress on these connections should be otherwise relieved

841

Yes but the nuance is that i over build. I could use thiner nickel stock and weld less than 6 points with the construction methods i use, but i want belt and suspenders quality. Copper, even when hardened from being worked is still softer than nickel and easier to manipulate. .2 feels good in the hand and i cant just get my mits on it good and tear it.

Is it good engineering, no. Way too much conductor and way too strong. Could save a bunch of money if you slim it down and move unitsā€¦ but thatā€™s not my cupa. :grin:

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842

Itā€™s advice like this that I come here for.

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843

I think the p30C should raw dog 0.2 copper.

I am not fully understanding the sandwich or flux reluctance.
If both reduce the heat entering the cell and increase the weld strength, im all for the extra time and effort required.
But Iā€™ve only built 3 small Esk8 batteries, and ā€˜raw dog copperā€™ just sounds right, So I accept the desire.

Maybe @DIY500AMP.COM still has this open box P30C, and is willing to test 0.2 copper, no nickel, no flux.

Ill give it a go with the P20b, but it seems unlikely.

1 Like
844

Time is money! Sandwiching seems like a total pain in the ass. Iā€™m definitely not opposed to flux tho

My reasoning is similar to Chrisā€™s in that iā€™d prefer to be overgunned than undergunned when it comes to tooling.

I only ever welded 0.15 nickel and even with 2 kwelds, i had them both maxxed out all the time. I would constantly need to stop and let the probes cool and it was annoying :joy:

Chris likes to overbuild, iā€™d like to overtool :joy:

3 Likes
845

Understood.

My first Battery, 10s2p, was rigid, and I did combo series parallel strips across 4 cells, Infinite slot, with two parallel stacked sandwiches 5mm wide with nickel prewelded to copper before positioning on cell and welding to cell.

I was all content with the feel and appearance of my welds using 65% or so of available power of cheapo purple welder.

When I read a critique of sharp corners on someone elseā€™s battery build, I went to use side cuts on my sharp corners, and some welds popped off way too easily.

I had established that technique and settings on a test cell sanded free if its nickel plating, and they did not translate to the new cells. Lesson learned.

I was so pissed off, I didnā€™t take the precautions whsn peeling off the failed i finite slot sandwich strips, and shorted one strip, which instantly turned red hot, and welded and stuck, and caused a prolonged curse fest. When finished I Had to manually top balance the shorted cells as the BMS was too slow and they were down ~200mv.

After dremelling the cells clean, I just upped the power to 85% and gave up on the time consuming infinite slot method.

That battery still works, it just gets too hot and sags hard, but I put a lot of cycles on it before retiring it, and it will likely see some range extender duties.

I didnā€™t like having to use 99% power to do 0.2 copper, 0.1 NPS with the P20B, and was happy the Flux lowered that to 79%, and seemed to fatten the 2 welded dots when I tore them off.

Need to experiment more, but had ran out of test cells.

Got some now though.

These pre sandwiches were certainly a pain in the ass to make. Iā€™m good at making things far more difficult than they need to be for little to no discernable benefit.

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3 Likes
846

What about capacitor discharge welding?

I once come across something online where a guy made a nice one with about thirty big electrolytics and onboard MOSFETā€™S / dual timer / gate driver.

I wanted to build one, but decided to buy a flipsky instead and spend that time building my boards and batteries, not building spot welders. *and of course, being flipsky - repairing the spot welder with genuine Fairchild Fets and a new gate driver.

Iā€™d like to buy something similar ready made. Anyone want to spend their time designing and drawing the PCB? I think there would be close to $500 in parts.

2 Likes
847

The AwithZ lineup of spot welders are supercapacitor based.

My P20B 14.6kW model takes close to two minutes to initially charge with a 15amp 9 volt power supply.

1 Like
848

My reluctance is to the sandwich and not flux. There are so many factors involved in getting it to stick right and not just conceal a poor weld that im not interested in testing and fitting up right plus the extra steps and doing double the work to prep and cut all the series &parallel connections. If im making 5 batters all with different layout and cells combinations it would quickly become a huge labor sink. I already make next to nothing for the batteries i build and it only just pays for a little surplus supplies and the tools i need to replace as i go. If it takes more time and doesnā€™t produce a better product than some easier equivalent product it makes it hard to justify

The need to clean the flux from between the connections is a bit of a drawback but copper has some unique properties as far as a weldable material goes and i already use a solvent when prepping nickel and so depending on how the actual process shakes out i want to be able to do without consistently.

2 Likes