Seen on Ebay: $200 Hobby Mini Battery Tab Spot Welder

[oatnet]

Not mine, but looks interesting:

http://www.ebay.com/itm/ws/eBayISAPI.dl ... 0809771247

[ohzee]

looks pretty neat - so far he's not sold a single thing on ebay I see just bought items so no word on happy customers.

[SamTexas]

I like it a lot. I would buy one if I have a need for it. Who cares if he hasn't sold any.

[neptronix]

Cool unit. Would this work for prismatic cells too?

[ohzee]

I like it a lot. I would buy one if I have a need for it. Who cares if he hasn't sold any.

Just making a observation.. I know when I go to buy something I like to see that other people have purchased the same
item and were happy with it. So personally I care.

[teklektik]

...Who cares if he hasn't sold any.

...I know when I go to buy something I like to see that other people have purchased the same
item and were happy with it. So personally I care.

+1

Neat looking unit, though. Seems to have gone through a few packaging iterations - different versions still for sale.

[oatnet]

This will not weld prisimatic tabs - the tabs don't have enough resistance. I don't expect these welders to be very good, but tab welders are expensive, so at this price, not so bad. I noticed that it said the unit needs to cool for a few minutes 'after a couple of sparks'.

-JD

[teklektik]

Tab welders are outside my experience but there's certainly no pulse width control. From the different time periods of welds in the video, it looks like power is applied as long as the pedal is down - and even those are pretty long weld times. I'm thinking this is good for messing around but you run the risk of overheating/melting the cell/tab material. Semi-production quantity welds needed for a sizable pack may well give uneven weld quality and possibly an unacceptable number of cell casualties.

[heathyoung]

Yep, not capacitive discharge, I'm betting that its a microwave oven transformer with the secondary hacked off, and rewound with a few turns of that 8GA cable.