I am with Jan. The laser thermometers are averaging over the whole patch you see lit up and they are not hugely accurate because of it. If the patch is larger from being farther away or not circular because it is on an angle - it will not report what you are hoping for. They are best for shining inside a uniform container, oven, furnace, etc. Or if at a wall, then you need to take a series of readings.
Imagine on one terminal you slide off to one side and average in some temperature from the top of the battery case. Or you have to get very close to one and far from another, and so on. Can you share what make and model of thermometer you are using? Mike On Thu, Aug 14, 2014 at 7:21 PM, David Nelson via EV <ev@lists.evdl.org> wrote: > If this is a change then I would investigate. I have had my pack in > for over 4 years and have not had the issue you and others have had > and my pack isn't exactly closed to moisture and dust. I have 40 > TS-LFP100AHA cells in a 2p20s arrangement. Because the BMS I used to > use attached to the heads of the terminal bolts I used brass bolts > since they are much easier to drill and tap threads in. This also > meant that I could assemble the pack and torque the bolts independent > of the BMS connections so they could not interfere with any > connections. Before assembling my pack I wire brushed all the > terminals to shine them up. I did this with NOALOX on the terminals > and SS wire brush so that the NOALOX would seal the metal as soon as > possible. I also tapped all the terminal holes again, using NOALOX on > the tap though this was probably way overkill. I did find some > terminals that didn't get tapped all the way down. I then put NOALOX > on the bolt threads before assembling. This was mostly so that the > soft Al and Cu terminals wouldn't gall up at all. I used bronze lock > washers, too. I have had no terminals come loose or get warm. > > Some may say that what I did was a waste of time but they can't > counter the results. It just works and I'm glad. LiFePO4 has been much > simpler than lead acid in many ways. If I were you I would clean all > the terminals using a similar process. If I were to do it over, and I > have on small 4-8 cell packs, I would use NO-OX-ID "A SPECIAL" because > it doesn't seem to get sticky over time like the NOALOX does. > > On Wed, Aug 13, 2014 at 2:20 PM, Danpatgal via EV <ev@lists.evdl.org> > wrote: > > I am using 38x130 ah CALBs in my Lectric Leopard and have had a too hot > (> > > 40C) warning on my BMS come on a few times in the last month or so. > Today, > > after a longer stretch of accelerating uphill to home, I checked some of > the > > battery posts. Measuring with a laser sensor, several of them were > around > > 33C , in a grouping, maybe 6 or 8 posts adjacent on the most positive > side > > of my pack. Posts just a few cells more negative were much cooler, maybe > > around 26C or cooler. > > > > I checked the bolts to make sure they were tight, and didn't notice any > real > > problem with the connections being loose. My only other thought is that > > perhaps (as has been discussed in other threads), these connections have > > corroded over time ... adding a little resistance layer (I didn't > initially > > polish or use Noalox on those) that is now finally heating up. I am also > > using the original copper straps with steels M8 bolts. > > > > Are others noticing this kind of heat with the lithium cell terminals? > > Aside from just cleaning the terminals and putting on some Noalox, might > > there be other things to do? I installed these in Sep. 2012, so they are > > not quite two years in service. > > > > Thanks - Dan > > > > > > > > ----- > > Dan Gallagher > > http://www.evalbum.com/3854 > > > > -- > > View this message in context: > http://electric-vehicle-discussion-list.413529.n4.nabble.com/CALB-bolt-terminals-getting-hot-tp4670981.html > > Sent from the Electric Vehicle Discussion List mailing list archive at > Nabble.com. > > _______________________________________________ > > 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) > > > > > > -- > David D. Nelson > http://evalbum.com/1328 > http://www.levforum.com > _______________________________________________ > 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) > > -- Put this question to yourself: should I use everyone else to attain happiness, or should I help others gain happiness? *Dalai Lama * Tell me what it is you plan to do With your one wild and precious life? Mary Oliver, "The summer day." To invent, you need a good imagination and a pile of junk. Thomas A. Edison <http://www.brainyquote.com/quotes/quotes/t/thomasaed125362.html> A public-opinion poll is no substitute for thought. *Warren Buffet* Michael E. Ross (919) 550-2430 Land (919) 576-0824 <https://www.google.com/voice/b/0?pli=1#phones> Google Phone (919) 631-1451 Cell (919) 513-0418 Desk michael.e.r...@gmail.com <michael.e.r...@gmail.com> -------------- next part -------------- An HTML attachment was scrubbed... URL: <http://lists.evdl.org/private.cgi/ev-evdl.org/attachments/20140814/f7dc57c4/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)
