BTW, I just now checked and found that the damaged battery is still at 6.27V so no immediate internal damage other than the missing post and a small hole melted in the top of the cell - which will obviously need to get patched also...
Cor van de Water Chief Scientist Proxim Wireless Corporation http://www.proxim.com Email: [email protected] Private: http://www.cvandewater.info Skype: cor_van_de_water Tel: +1 408 383 7626 -----Original Message----- From: [email protected] [mailto:[email protected]] On Behalf Of Cor van de Water Sent: Thursday, March 28, 2013 1:18 PM To: Electric Vehicle Discussion List Subject: [EVDL] Re-casting battery post that melted away? Yesterday on my way from work I lost all motive power in my EV truck, after an initial warning when I just entered the freeway of a short power loss but since I was eager to get where I was going to and did not want to pull off the freeway, I kept going. Frankly - I hardly recognised the brief loss of power as a warning that something was amiss, but I would soon found out that the warning was serious and I should have taken action right away. Few more miles down the road I was about to go up an overpass where freeways intersect and I lost all power. Lights still worked so 12V was still available but no power from the pack. I was still hopefull that my 200A breaker finally tripped on my sustained 300A draws while I coasted to the side of the road, but looking under the hood I saw the breaker still in ON position. I turned it off anyway and back on - maybe it would reset something? But no - still no power, even the display in the car did not light. Hmmm - that meant that there was actually no power from the pack, not some controller error. Grabbing the multimeter I checked and indeed - no voltage from the pack. The front 4 batteries were fine and delivered 6.2V each so I undid the bolts for the bed and lifted it up (after walking back 50 yards to set out a warning cone on the edge of the shoulder since my hazard lights are not visible much with the bed lifted). In the middle of the pack I spotted a yellow blur under a clamp that was desperately holding onto air.... Where did the post go? As you can see on this picture: http://evalbum.com/popupimg.php?24271 the post melted and the lead had run onto the next battery, covering the entire width of that battery with a strip of lead. More pics on the EValbum page: http://evalbum.com/4259 Luckily with a wrench I could undo the damaged interconnect (the clamp on the other side, on the next battery) and move the clamp from the other post of the damaged battery to the now free clamp on the next battery, removing the bad one from the string and continuing on my way on a 114V pack. Anyone a recommendation where I can best have a post re-cast? I am in San Francisco South Bay area (AKA silicon valley). I have an alternative for the damaged battery, since the truck is setup up with 22 identical batteries - 2 are used as aux battery and serve as spares, so I can swap one of those into the pack and only need to connect to the damaged battery for the aux load, which is typical no more than 20A instead of the 300A that the pack will see. Still I prefer to have a post again on this battery. Regards, Cor van de Water Chief Scientist Proxim Wireless Corporation http://www.proxim.com <http://www.proxim.com> Email: [email protected] Private: http://www.cvandewater.info <http://www.cvandewater.infom> Skype: cor_van_de_water Tel: +1 408 383 7626 -------------- next part -------------- An HTML attachment was scrubbed... URL: <http://lists.evdl.org/private.cgi/ev-evdl.org/attachments/20130328/5637 baa0/attachment.htm> _______________________________________________ UNSUBSCRIBE: http://www.evdl.org/help/index.html#usub http://lists.evdl.org/listinfo.cgi/ev-evdl.org For EV drag racing discussion, please use NEDRA (http://groups.yahoo.com/group/NEDRA) _______________________________________________ UNSUBSCRIBE: http://www.evdl.org/help/index.html#usub http://lists.evdl.org/listinfo.cgi/ev-evdl.org For EV drag racing discussion, please use NEDRA (http://groups.yahoo.com/group/NEDRA)
