Tesla does this on newer S/X. There is a small always-on DC-DC that powers the telematics and keeps it from deep-cycling the 12v AGM.
You still need a 12v battery to stiffen the 12v bus, provide load dump capability, and emergency power for braking/steering should the HV system fault though. On early S/X that didn't have this, the contactors would have to close several times a day to recharge the AGM as it cycled. This meant you got about 2-3 years out of it, and firing up the whole system just to top off the 12v took a lot of range out. Most EV's have this issue. With the large amount of connectivity in modern vehicles, I suspect the 12v will be here for some time to come. On Tue, Dec 15, 2020 at 3:34 PM Ken Olum via EV <[email protected]> wrote: > We have a 2013 Leaf and have replaced the 12V battery. In my opinion > this battery should not exist. It's just something to break or wear > out. Instead the DC/DC converter should run all the time (yes, it's > possible to build such a converter that is efficient at low loads), and > there should be some software to ensure that the total drain from the > traction pack is not too large, with some way to reset the system when it > has cut out for this reason. > > Ken > _______________________________________________ > 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) > > -------------- next part -------------- An HTML attachment was scrubbed... URL: <http://lists.evdl.org/private.cgi/ev-evdl.org/attachments/20201215/e884195c/attachment.html> _______________________________________________ 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)
