Lawrence, 10000 cycles is possibly doable with any Li ion cell, if you run it right. That is the rub, could be you only use 40% of the capacity, or only run it below 30C, or the cycles are really fast. If you pick the right sort of test you can get a long cycle life. So the question is really, can you get the performance you want and manage them for long life.
The best candidate for use in a car, as opposed to an medical implant, or a hearing aid, is probably what Tesla uses. A whole lot of cylindrical cells. I think they use LiNiCoAl cells. They are long life, high specific energy, high specific power, good performance, and low cost. [ from p3 of https://www.bcg.com/documents/file36615.pdf and the Handbook of batteries 4th ed. ] NCA are potentially less safe. Tesla has a fusible link on every cell. That should go a long ways towards protecting the pack from a meltdown. You would probably need to learn how to weld conductors on to them. I don't think pressing a conductor against them will be satisfactory. See the Tesla pack torn down: http://files.wizkid057.com/teslapack/2014-08-19%2019.12.44.jpg from http://www.teslamotorsclub.com/showthread.php/34934-Pics-Info-Inside-the-battery-pack Then you have to guess how to run them well. When to cut them off. You never want to charge them fully, always some headroom. If you charge fast you may need cooling. The cells die because they are charged fully AND exposed to too hot a temperature at the same time. If you avoid those two factors you have done most of what you can. Can you buy Tesla cells? You might be able to scavenge some from a wreck and get a good deal. They would be high quality cells, but you might not know their history. Who knows what the going price would be. On Mon, Mar 30, 2015 at 3:13 AM, Lawrence Rhodes via EV <[email protected]> wrote: > Having said that, there are vast differences in cycle life between > brands. Some only last 500 cycles, while others last well over 10,000 > cycles. There are also large differences in calendar life between brands > as well. > > Bill D. > I would love to know which batteries have what cycle life and other > characteristics beneficial to a long lasting pack that is usable and not > having to be babied. Bill, do you have time to share? Lawrence Rhodes > -------------- next part -------------- > An HTML attachment was scrubbed... > URL: < > http://lists.evdl.org/private.cgi/ev-evdl.org/attachments/20150330/bede402d/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) > > -- 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) 585-6737 Land (919) 576-0824 <https://www.google.com/voice/b/0?pli=1#phones> Google Phone (919) 631-1451 Cell [email protected] <[email protected]> -------------- next part -------------- An HTML attachment was scrubbed... URL: <http://lists.evdl.org/private.cgi/ev-evdl.org/attachments/20150330/eb0ab46b/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)
