Building Lithium Batteries ? Which Spot Welder is For You?

Re-uploaded without music HERE https://youtu.be/JQoNBRrjsdo?si=9jmaOFRsoBQsbvcH

Man you guys are on point. It seems like every time I have a question about how to build my e bike build, your videos are the best and most in depth. Non biased, straight forward information. Just keep doing what your doing and you'll help more people than you know.

Nice video EXCEPT for the music which was annoying!

Great review! - I'm a 75 yr old guy planning a 48v battery build for my converted Specialized stump jumper that I'm going to use on Vancouver Island this summer - I already bought the AwithZ unit and although it did a good job on the included nickel plated steel, after watching your review I tried it out with some 1.5 pure nickel and it didn't stick very well. Thinking I should return it and get something else. Thanks guys!

Sweet! Wish there was a video like this years ago... Thanks, man!

I’m getting ready to remake a small battery pack (6 cells) and you answered a ton of questions that I had, now I know that the small self contained welder will work fine for what I’m going to need it for, thanks.

Thanks for taking the time to review the various types of welders and helping those considering a welder to gain some knowledge into the various options. That said IMHHO the welders should not just stick the strip to the battery. An OK weld will be take moderate effort to pull off with pliers, a proper weld will tear out sections of the strip. To me acceptable of most pack construction and Somewhere in the middle is a weld that (on tear off) is causing a decent amount of material transfer from the strip....IE the weld although not penetrating the strip fully causing tear out of small sections of the strip, it will melt enough of the strip to cause a substantial depression in the strip and corresponding deposition of nickel onto the battery terminal. This is the minimum I would consider acceptable for two reasons. One is that anything with less weld penetration and area will be transferring the current through a small area (when in use) and this will generate a lot of localized heating that over time will fatigue the weld and can cause it to separate. The second issue is even if this is in a very low current draw pack (say a true 250-350w e bike) the vibration of the cells in the pack encountered over bumps can also cause fracture of the welds.

this ... music. That's why I have blood in my ears now! 😫

Please consider posting the video without the background music, as the music is very annoying to me snd possibly others.

This was the video I was waiting for, Thanks. Liked the honest and surprise reaction to how well the capacitor welder worked. You will still build my E-bike battery packs, but I have smaller 12v -18v packs to repair. Thank again

This is great, great information! I live off grid and can't supply the AC current peaks that plug in bench mount welders draw, and the handheld cell powered welders really don't have enough power, as we saw. I was about to spend the big bucks on the Kweld kit , (about $400 cad to my door) but the capacitor unit you showed worked well and will sip power from my solar setup. Such real and useful material is like gold. Thank you.

You know what I liked best about this video? Those 2 batteries being built looked very familiar!😅

Keep up the work, this video was very helpful

I returned the AwithZ unit and bought the purple unit with a small car battery. excellent results.

Thanks for the review. You helped me much.❤

Hey, a useful video. Thank you for it!

Great video keep up 🌱

Great video definitely like the k welder the best because it is adjustable and can possibly also do other thin metels Thanks for the great videos always learn alot

Great information for a newbie like me.....I am amazed at the technology ...but still think I will buy from legitimate seller. Looks like it will be time consuming to build a big battery. Glad I subscribed! Always trying to learn something and your Channel helps make that possible!!

There is no huge bank of capacitors inside the cap based welders. Every model I've seen online uses ultracapacitors and typically they use 2000F to 3000F capacitors...now the quality of those caps varies widely. The sub $100 ones likely have used caps in them so the internal resistance of the caps is significantly higher. Resistance Spot Welding is 100% about resistance. You can use an AC IR milliohm meter like the RC3563 or YR1035+ to take measurements to help you build a powerful welder but remember DC IR is NOT the same as AC IR. DC IR is typically 50% to 100% more than AC IR. Between your power source, welding circuit (mosfets), cabling and electrodes you want somewhere in the single digit milliohm range to weld 0.15mm or 0.20mm pure nickel. The simplest upgrade someone can make to an off the shelf spot welder is to use a thicker gauge of silicone insulated wire for the cables/electrodes. Keep in mind that using cables that are TOO large (the kWeld has a section on this in their manual) can cause too much inductance and blow up your welding circuit. Also keep in mind pure copper is not the most ideal alloy for spot welding nickel to steel cans. There's websites with this info but aluminum copper alloys are usually what is used in this application. The built in Lipo style welders are convenient but you never really know what you're getting inside the box....and the RC Lipo world is full of absolute bullshit C ratings....100C...200C...all bullshit. Nothing out there is over 50C and the best of the best Lipos are 30C to 40C typically. 25C is pretty standard for your average "100C" rated Lipo. The fact that you have to discharge the Lipo to storage voltage (3.85V'ish) every time you go to store the unit for more than a day or two means its a lot of extra work and you'll likely forget. I rarely see these lasting longer than a year. Look for one that advertises having a USB output for charging a phone or something. Use that as a discharge port so you don't have to open up the case the Lipo is in. Stupid feature that actually has a necessary alternative function. High power LiFePO4 and LTO packs are going to be the best long term power sources besides super capacitors and ultra capacitors. Used Headways from BatteryHookup.com are cheap and if you buy enough for a 3S2P or 4S2P pack you'll get enough power to do 0.20mm nickel so long as the PCB you match it with has good mosfets. Do some research on the mosfets on the PCB you are looking at or buy one of the DIY mosfet boards on Aliexpress and some copper bar stock and build a beast of a fet board using IRL40SC228's or something similar. I can link all the Aliexpress components necessary to build your own spot welder that will outperform a kWeld for about $100 plus a $100 battery.