The Classic Prius pack never sees currents above 60 Amps and I doubt that the material is steel since I have never seen it rust. The pack is sitting behind the rear seat, so it definitely was not under water ever, but condensation is possible and more importantly the cells are not properly sealing. They have a vent on top, but early cells leaked at their terminals, causing this corrosion from the electrolyte and therefor the terminals get a buildup of corrosive electrolyte deposited by the outgassing and leaking. *this* will corrode the bus bar on the terminals quickly and Toyota's Service Campaign on this issue has been to rework all Classic packs for free with sealing glue and cleaning of the bus bars. It took them 2 days on my Prius, back in 2005.
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 Martin WINLOW Sent: Thursday, January 09, 2014 9:10 AM To: Electric Vehicle Discussion List Subject: Re: [EVDL] Keeping LiFePO4 battery terminals tight every 10k miles Ye Gads! I wouldn't like to see that same picture 10k miles from now. Has this pack been submerged or something? Plated steel is a very poor idea! MW On 8 Jan 2014, at 16:32, Peter Gabrielsson wrote: > Here's a picture of what Toyota use in their prius battery terminals: > http://techno-fandom.org/~hobbit/cars/batbox/80corropen.jpg > > Notice the nut with the captive bellville washer. They used the same type > in their RAV4 EVs. > > > > On Wed, Jan 8, 2014 at 7:48 AM, Michael Ross <[email protected]>wrote: > >> Martin, >> >> I have no experience with the aluminum post cells. But it is just >> aluminum. Aluminum is elastic and will not take a set, so it is just fine >> for torquing to a level that will not give up. From my POV there is not >> much more to be said about it. The use of split washes concentrates the >> clamping forces and make the joint less effective. They are a waste of >> money and stack height from a design engineer's POV. But if you use them >> it is probably not a problem. They only work as a lock after the joint is >> completely loose, however; and they don't actually stop the joint from >> loosening before that point. The loss of joint clamping force is caused by >> materials in the joint stretching or compressing. You won't find a split >> washer on a Cat, Deere, Toyota, Ford, you name it product. However they >> are popular no denying that. With Al for a threaded member you don't need >> hardened washers, because you can't clamp hard enough to get utility from >> them. But you do want flat, clean, metal only, parts in the stack. >> Belleville washers are not a bad idea, they help maintain clamping force >> as a joint loosens. Maybe the Norlocks do some of that too. >> >> >> Dave Roden, >> >> Head bolts have hardened flat washers. They use large fasteners as and >> torque them VERY high to completely take any compliance out of the head >> gasket, and many use a torque to yield technique where you don't even >> measure the torque* per se *- you torque until the bolt stretches >> permanently. With good steel and high quality manufacture you can take a >> head bolt into the plastic range and it will not be damaged to cause >> failure, if you do this you get the maximum force possible. >> >> >> Lot's of nice replies, but I just hit these two for commenting in the short >> time I have right now. >> >> >> On Wed, Jan 8, 2014 at 11:09 AM, EVDL Administrator <[email protected]> >> wrote: >> >>> On 8 Jan 2014 at 6:03, tomw wrote: >>> >>>> And while you are at it, remove those lock washers! :^)) >>> >>> I'm really surprised to hear people say this. I've used split washers >> and >>> Bellville washers on batteries for 25+ years, and they've done me well. >>> >>> I also can't recall ever encountering any bolted battery connection on >> any >>> commercial product that didn't have a lockwasher. And think about it - >>> have >>> you ever seen any case in a vibrating, lurching vehicle where there >> wasn't >>> something resilient (a head gasket for example) that lockwashers weren't >>> used? >>> >>> One thing to be careful of is that you want your lug in direct contact >> with >>> the battery terminal itself, with no washers between them to add >>> resistance. >>> You add the washer(s) between the fastener and the lug. >>> >>> Some discussion too of terminal glop. With flooded batteries, I normally >>> use petroleum jelly to exclude air and moisture. Many years ago I got a >>> free can of some kind of Cosmolene-like spray with an order of USBMC golf >>> car batteries. That stuff worked well too and was easy to use. The >> key, I >>> think, is that I put the goo on AFTER tightening the connection, not on >> the >>> mating contact surfaces. (Though I've known people who DID use grease on >>> mating surfaces.) >>> >>> I don't think I've ever bothered with grease when using valve regulated >>> batteries, however. Maybe I should have, but nothing bad has yet >> happened. >>> >>> To get back to the point, I'm pretty skeptical about washerless battery >>> connections. If you try this, please make sure you keep us updated on >> how >>> it's going over time. For now, though, I'm sticking with lockwashers. >>> >>> David Roden - Akron, Ohio, USA >>> EVDL Administrator >>> >>> = = = = = = = = = = = = = = = = = = = = = = = = = = = = = >>> EVDL Information: http://www.evdl.org/help/ >>> = = = = = = = = = = = = = = = = = = = = = = = = = = = = = >>> Note: mail sent to "evpost" and "etpost" addresses will not >>> reach me. To send a private message, please obtain my >>> email address from the webpage http://www.evdl.org/help/ . >>> = = = = = = = = = = = = = = = = = = = = = = = = = = = = = >>> >>> >>> _______________________________________________ >>> 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 >> >> [email protected] >> <[email protected]> >> -------------- next part -------------- >> An HTML attachment was scrubbed... >> URL: < >> http://lists.evdl.org/private.cgi/ev-evdl.org/attachments/20140108/bc05d e28/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) >> >> > > > -- > www.electric-lemon.com > -------------- next part -------------- > An HTML attachment was scrubbed... > URL: <http://lists.evdl.org/private.cgi/ev-evdl.org/attachments/20140108/512c fd4b/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) _______________________________________________ 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)
