My wife's (chinese) e-bike came with a 28V 10Ah pack that can be removed from the bike and stored/charged separately. Its BMS will protect and balance the pack (7s4p laptop cells) nicely. Its BMS also has a max current limit, for which I am very thankful so that when the controller failed, the power automatically shut off instead of creating a smoke show.
For a cranking application, that is of course not desired unless the max current limit is in the order of 1000A. Seeing currents like that coming from this chemistry, I hope that they are using A123 cells as I do not believe that many other manufacturers allow this kind of discharge currents... 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 Jerry Yue Sent: Friday, February 15, 2013 5:47 PM To: Electric Vehicle Discussion List Subject: Re: [EVDL] 12V LiFePO4 batteries Personally, I do not think LFP can be widely used for replacement of the underhood lead acid battery. It's an interesting try for those who are interested in new technlology. LFP's long life and maintainence free are got under lab condition and complex management. Not all bms' are good for managing your battery. If the bms fails, you'll find the LFP fails earlier than your lead acid battery. Before you decide to use the 12V40AH battery, you'd better get to know whether the battery has a max discharge current limit. If the limit value is lower than your crank current, the battery will be protected and fail to work when you try to start your car. Jerry On Sat, Feb 16, 2013 at 1:24 AM, Bruce EVangel Parmenter < [email protected]> wrote: > In my original post on this thread, I was looking at > > http://www.ebay.com/itm/12V-40Ah-LiFePO4-Lithium-Prismatic-Battery-Pack- with-AC-Charger-LP500-/250996143478?pt=Laptop_Batteries&hash=item3a70893 576 > > which comes with a matching charger that can run off either 110VAC or > 220VAC. > > I plan to disconnect the 12V leads from the house genset as there is no > control over the voltage coming out of there. The li-ion would be only > recharged via the small included AC charger. My Amperage loads should be > not too high (100A to power an inverter providing 110VAC, or to start > the small genset, ~200A?). > > A Trojan group 24 > > http://www.batteriesinaflash.com/deep-cycle-lead-acid/12v/trojan-24tmx-1 2v-85ah-group-24-flooded-deep-cycle-battery > costs ~$170. The li-ion costs $550. It costs 33% more, but has a longer > life, and its it maintenance-free. > > > {brucedp.150m.com} > > > > - > On Fri, Feb 15, 2013, at 05:55 AM, Byron James wrote: > > Instead of charging the lifepo4 batteries directly from the alternator, > > is it possible to insert a lifepo4 charger in between the alternator and > > battery. > - > > -- > http://www.fastmail.fm - One of many happy users: > http://www.fastmail.fm/help/overview_quotes.html > > _______________________________________________ > 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) > > -------------- next part -------------- An HTML attachment was scrubbed... URL: <http://lists.evdl.org/private.cgi/ev-evdl.org/attachments/20130216/f155 82e5/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)
