Battery Welding Technique

[saneagle]

After many years, my Sunkko welder has given up, so I thought I'd replace it with an easier to use portable one. I got this one from Amazon:

https://www.amazon.co.uk/Seesii-11000mA-h-Upgraded-Enhanced-Adjustable/dp/B0B45SV2GB/ref=sr_1_49_sspa?crid=1E7UCBYQ9RFAH&keywords=spot%2Bwelder%2Bfor%2B18650%2Bbatteries&qid=1693566704&sprefix=%2Caps%2C76&sr=8-49-spons&sp_csd=d2lkZ2V0TmFtZT1zcF9hdGZfbmV4dA&th=1

two of us tried it on every setting and with several different types of strip, but we couldn't get a single weld to hold.

I replaced it with this one:

https://www.amazon.co.uk/Seesii-11000mA-h-Upgraded-Enhanced-Adjustable/dp/B0B45SV2GB/ref=sr_1_49_sspa?crid=1E7UCBYQ9RFAH&keywords=spot%2Bwelder%2Bfor%2B18650%2Bbatteries&qid=1693566704&sprefix=%2Caps%2C76&sr=8-49-spons&sp_csd=d2lkZ2V0TmFtZT1zcF9hdGZfbmV4dA&th=1

Same story - tiotally useless.

Later, I looked on Youtube and saw a guy welding with a similar one, and he was getting mixed results, and he blamed the bad welds on pressing too hard on the electrodes. he said you just have to touch the strip with no weight on it, and that seemed to give mainly OK welds. The problem is that you normally need to apply some pressure to hold the strip to the battery otherwise the electrode just blows a small hole in the strip.

I know some of you have tried this type of welder. How do you do it, which one do you use and what sort of results do you get? I've managed to weld one side of the battery, but I don't know if I can trust the welds.

I've ordered a replacement Sunkko, but it's got to come from China,so a few weeks to get here, and we need to press on.

 

[Nealh]

They likely simply can't deliver enough current to get the weld to penetrate, that said I have never tried one or would waste my money on one.
Better spending your cash on a better Arduino type like the malectric or Kweld, though a lot mire dearer they do deliver the goods if one uses a good high rate battery. The 3s lipo I use has a 65c rating so one has to factor in the lipo cost as well, that said my lipo must be 6 years old now and still a solid performer.

 

[WheezyRider]

After many years, my Sunkko welder has given up, so I thought I'd replace it with an easier to use portable one. I got this one from Amazon:

https://www.amazon.co.uk/Seesii-11000mA-h-Upgraded-Enhanced-Adjustable/dp/B0B45SV2GB/ref=sr_1_49_sspa?crid=1E7UCBYQ9RFAH&keywords=spot%2Bwelder%2Bfor%2B18650%2Bbatteries&qid=1693566704&sprefix=%2Caps%2C76&sr=8-49-spons&sp_csd=d2lkZ2V0TmFtZT1zcF9hdGZfbmV4dA&th=1

two of us tried it on every setting and with several different types of strip, but we couldn't get a single weld to hold.

I replaced it with this one:

https://www.amazon.co.uk/Seesii-11000mA-h-Upgraded-Enhanced-Adjustable/dp/B0B45SV2GB/ref=sr_1_49_sspa?crid=1E7UCBYQ9RFAH&keywords=spot%2Bwelder%2Bfor%2B18650%2Bbatteries&qid=1693566704&sprefix=%2Caps%2C76&sr=8-49-spons&sp_csd=d2lkZ2V0TmFtZT1zcF9hdGZfbmV4dA&th=1

Same story - tiotally useless.

Later, I looked on Youtube and saw a guy welding with a similar one, and he was getting mixed results, and he blamed the bad welds on pressing too hard on the electrodes. he said you just have to touch the strip with no weight on it, and that seemed to give mainly OK welds. The problem is that you normally need to apply some pressure to hold the strip to the battery otherwise the electrode just blows a small hole in the strip.

I know some of you have tried this type of welder. How do you do it, which one do you use and what sort of results do you get? I've managed to weld one side of the battery, but I don't know if I can trust the welds.

I've ordered a replacement Sunkko, but it's got to come from China,so a few weeks to get here, and we need to press on.

I've had very similar experiences. Bought one of those handheld welders and it makes a good flash and leaves a melted spot on the top of the metal, but the two pieces just fall apart again. I bought it after seeing someone online welding stuff with apparent ease.

The Sunkko welder was ok, apart from the fact it often used to take down the house electrics after a few welds. Then it would blow the 20 A fuse (in the supplied 13 A plug and 10 A mains lead!) on a regular basis. Plus after about 50 welds, you'd have to stop as smoke would start wafting up from the transformer. I still have it, but I've run out of 20 A fuses.

I bought one of those bare bones modules with the micro controller and MOSFETs for connecting to a car battery. It did a few welds, then died completely.

 

[saneagle]

I've had very similar experiences. Bought one of those handheld welders and it makes a good flash and leaves a melted spot on the top of the metal, but the two pieces just fall apart again. I bought it after seeing someone online welding stuff with apparent ease.

The Sunkko welder was ok, apart from the fact it often used to take down the house electrics after a few welds. Then it would blow the 20 A fuse (in the supplied 13 A plug and 10 A mains lead!) on a regular basis. Plus after about 50 welds, you'd have to stop as smoke would start wafting up from the transformer. I still have it, but I've run out of 20 A fuses.

I bought one of those bare bones modules with the micro controller and MOSFETs for connecting to a car battery. It did a few welds, then died completely.

My Sunkko one has started tripping the RCD. I took it all apart , and it worked fine while apart, so I put it all back together, and it tripped the RCD again.

 

[WheezyRider]

My Sunkko one has started tripping the RCD. I took it all apart , and it worked fine while apart, so I put it all back together, and it tripped the RCD again.

I had to resort to taking mine to a friend's house with 60s wiring and no RCD Then it would tend to blow the 20 A fuse in the 13 A plug after about 10 to 20 welds. I had a pile of these fuses at one point, but have burned through them all now.