Valance batteries already have a BMS built in. In addition, LiFePO4 cells have the highest thermal runaway temperature I believe it’s 250C so much safer than other chemistries. We overcharged one for 4 hours one time as a test. It melted the plastic casing and vented but never caught fire. I have a video of it I can post. Not to say they can’t go into thermal run away but much less likely. Just because an engineer developed a BMS does not make it good. It was an engineer that designed the lap top batteries that caught fire as well. Pick a product that’s got a good track record and has been around a while. I think wiring is much susceptible to fire and with a BMS you have many more connections. Pay close attention to details when connecting a BMS.
Sent from my iPhone > On Jun 7, 2020, at 11:59 PM, EVDL Administrator via EV <[email protected]> > wrote: > > Lithium batteries have an insane amount of energy in a small space. A > little carelessness or ignorance and they can burn your house down, maybe > with you and your family inside. > > You prevent lithium disasters with close and redundant battery monitoring. > If you're a really good engineer, you can design that yourself (but you may > have some near-disasters along the way). If you're a shadetree mechanic > like you or me, you can buy it. But buying a BMS mainly on price is - let's > say - a rather risky move. > > Lawrence, a lot of I read from you in your posts is such words as > "inexpensive" and "cheap." Budget hacks can get expensive fast if they > catch fire. Not to be an alarmist, but I'm sure you don't want to become a > "SF EV Hobbyist Dies in House Fire" headline. > > I suggest that you spring for a proven lithium battery *system* designed by > someone who knows his or her stuff, and made by a qualified manufacturer > that isn't some here-today-gone-tomorrow Chinese sweatshop. As far as I > know, your Valence batteries are one such system. > > If you're not willing to spend a reasonable amount on a safe lithium battery > system, then please stick with good old lead batteries. Bob Rice's infamous > "Trojan Teakettles" notwithstanding, they're a lot less likely to hurt you > when they're mistreated. > > 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 > ARCHIVE: http://www.evdl.org/archive/index.html > INFO: http://lists.evdl.org/listinfo.cgi/ev-evdl.org > Please discuss EV drag racing at NEDRA (http://groups.yahoo.com/group/NEDRA) > _______________________________________________ UNSUBSCRIBE: http://www.evdl.org/help/index.html#usub ARCHIVE: http://www.evdl.org/archive/index.html INFO: http://lists.evdl.org/listinfo.cgi/ev-evdl.org Please discuss EV drag racing at NEDRA (http://groups.yahoo.com/group/NEDRA)
