On 4 Sep 2016 at 15:22, Jan Steinman via EV wrote: > Does anyone know if the same holds true for flooded-cell NiCd?
I don't know for sure that it applies to BB-600 type cells, but according to the technical manual for the Saft STM range of EV NiCd monoblocks, "The blocks must be mechanically supported and must not be able to move in any horizontal or vertical direction. Only the small sides of the blocks must be braced in case of connection of rows of several blocks. In practice, the blocks will be set up in rows in the axis of the small sides, without any gap. A supporting structure at the two ends of the row (either bracing or battery box) must withstand an expanding force from the battery of approximately 150 dN per row." So, I would say that the answer is "probably." FYI, the manual goes on: "On their longer side, the blocks must be set up with a gap. A ventilation space of 14 to 20mm must be foreseen between the rows ..." You can download the entire Saft tech manual here: http://www.evdl.org/docs/STM5-180tech.pdf > I was planning to use a solid copper bus bar, but if they change size > considerably, that is probably not a good idea. :-( It's not just the expansion, it's movement in normal driving. In any vehicle, where the body jounces and flexes, it's really difficult to keep them perfectly still relative to one another. The STM5-100/140 blocks had what appeared to be rubber seals around their terminals. As assembled into battery packs at the Saft factory, these monoblocks were glued into a plastic base to hold them in place. However, they DID move when pushed and I assume also when the vehicle was moving. I trust that the flexible terminal mounting allowed for slight movement. These blocks were interconnected with solid nickel plated bars rather than cables. However, the photo on the front cover of the manual for the blocks showed them interconnected with what appear to be flexible cables. http://www.evdl.org/docs/stmuk.pdf I would recommend cables over rigid bars if there is any chance that the blocks can move significantly relative to one another. You should use plated lugs and try to keep the plating intact. Use Belleville spring washers, not toothed or split washers. Others may have further suggestions for you. 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 Read EVAngel's EV News at http://evdl.org/evln/ Please discuss EV drag racing at NEDRA (http://groups.yahoo.com/group/NEDRA)
