At 07:03 PM 1/30/02 +1100, Roman Black wrote: >Welded tabs cause MUCH more heat and damage to >the battery, and besides the risk of mechanical >failure from vibration (i've fixed a few) they >WILL NOT take the very high currents needed for >electric model vehicles etc. Welded tabs are >very much a mass-produced low-quality low- >performance solution. Sorry to disagree here, but my local supplier (just down the street!) welds up cells with NO discernable heat remaining after the weld is complete. Each weld is actually 2 welds: one from each tip. They do each strap at least twice (4 welds) unless you specify high current usage - then they use wider straps and weld 5 or 6 times. I accidently shorted a pack made of full size C cells: one of the straps eventually melted! But the welds were intact. I'm guessing the short circuit current was several hundred amps. I've used their welder and done my own cells. The whole thing is pretty automated - step on the foot-switch and the welding tips come down at a controlled rate. There are some tiny sparks a short time after the tips hit the strap - then they stop. Let go of the foot switch and the tips come back up. I don't know if I could make a bad weld even if I tried. dwayne Dwayne Reid Trinity Electronics Systems Ltd Edmonton, AB, CANADA (780) 489-3199 voice (780) 487-6397 fax Celebrating 18 years of Engineering Innovation (1984 - 2002) .-. .-. .-. .-. .-. .-. .-. .-. .-. .- `-' `-' `-' `-' `-' `-' `-' `-' `-' Do NOT send unsolicited commercial email to this email address. This message neither grants consent to receive unsolicited commercial email nor is intended to solicit commercial email. -- http://www.piclist.com#nomail Going offline? Don't AutoReply us! email listserv@mitvma.mit.edu with SET PICList DIGEST in the body