...and, I should add: Nissan in their manual calls 110V charging "trickle charging," even though the only difference is the speed that electrons get pushed into the right side of the battery. It will still stop charging at 80% or 100%, whichever you specify.
b& On Jun 3, 2015, at 9:58 AM, Michael Ross via EV <ev@lists.evdl.org> wrote: > Paul, > > What is the reasoning there? *IF the cut off voltage is not exceeded* (and > it is low enough) then there should be no problem with very low current > charging. > > However, to many people "trickle charge" means an unmanaged charge that > continues beyond a cut off point. You will definitely ruin Li ion cells if > you never stop the low current charging. > > Lead acid cells, which always lose some charge, are not damaged at all by > overcharging that does not heat them, and for which losing all charge is > bad, are a good candidate for trickle charging. > > I suspect this is all stuff you know, but I wanted to get this in the > thread for posterity. > > On Wed, Jun 3, 2015 at 12:17 PM, Paul Dove <dov...@bellsouth.net> wrote: > >> Absolutely never trickle charge any type of Lithium Ion battery >> >> Sent from my iPhone >> >>> On Jun 3, 2015, at 11:12 AM, Ben Goren via EV <ev@lists.evdl.org> wrote: >>> >>> Thanks, everybody, for all the advice. >>> >>> Sunday evening when I had dinner at their place, I set the car to only >> charge to 80%. I also set the timer so that it'll finish charging by 6:00 >> am, thinking that that was when their time-of-use plan kicked up to the >> higher rate. They actually don't have a morning restriction, only an >> afternoon one, so I'll probably change that to 8:00 am, so that any >> charging will be a closer match for the coolest part of the day...it'll be >> cooler at 8:00 am than 10:00 pm, with 6:00 am about as cool as it gets. >>> >>> One relevant question...they've only got the 110V charger with the car. >> It's plenty for their actual charging needs...but the Nissan manual pretty >> clearly says that Nissan doesn't recommend "trickle charging." Does anybody >> know if that's a "you'll damage your pack if you always trickle charge" >> recommendation, or if it's a "you'll die of frustration watching paint dry >> in the time it takes to charge" recommendation? If the latter...not a >> problem. A very, very long day of driving for them would be 50 miles, and >> that'd easily go back in the battery overnight. The former...would be worth >> getting something Dad can plug into the 220 outlet in the garage. >>> >>> The garage has a not unreasonable amount of insulation...not ideal, but >> as much as is practical. And there's a window A/C unit mounted in the wall >> that they'll leave on when it's hot. >>> >>> A swamp cooler is out for the other reasons mentioned, and for the fact >> that Dad does a lot of woodworking in the garage, and the big humidity >> swings would be a problem. >>> >>> The Leaf is a bit bigger than the '55 VW Bug that previously lived in >> the garage (and is now going to live in the carport), so Dad was busy >> making room in there and backing in and out yesterday when I stopped by for >> a minute. They haven't charged the car yet and it still has 40 miles on the >> guess-o-meter. >>> >>> All in all, definitely a wise investment. Amortized over several years >> or so, it's a net financial gain...and the money they used to pay for the >> car was sitting in an account not doing anything. The month-to-month >> expenses are going to be significantly less, so it'll feel to them like >> they've got more money to play with. And they won't have to get gas, >> there's no maintenance, and all the rest. And it's a really nice car to >> boot. Probably the best thing they've done with their money since they paid >> off their mortgage early. >>> >>> Thanks again, everybody, for all the advice! >>> >>> b& >>> >>>> On Jun 1, 2015, at 9:05 AM, Michael Ross via EV <ev@lists.evdl.org> >> wrote: >>>> >>>> In a phone conversation, Dr. Dahn told me that LFP starts deteriorating >> a >>>> 104°F when fully charged. >>>> >>>> You can simply not charge fully. Exactly how not fully? I don't know. >>>> Also there may be differences depending on the form factor, source of >> the >>>> electrode, electrolyte compositions, and so on. >>>> >>>> No rules of thumb here, but you may want to prudently reduce the charge >>>> cutoff voltage. The difference between 3.4V and 3.7 could be huge in >> terms >>>> of cell life, particularly if the pack gets hot when charged. >>>> >>>> This is complicated by the general rule not to ever, ever charge Li ion >>>> cells in your residence. >>>> >>>> Mike >>>> >>>>> On Mon, Jun 1, 2015 at 10:40 AM, tomw via EV <ev@lists.evdl.org> >> wrote: >>>>> >>>>> My garage is a steel building with no insulation. In summer it >> typically >>>>> is >>>>> 10 to 15 F warmer than outside temperature. You can feel the IR >> radiation >>>>> from the walls and roof, like being in an oven, and the metal is hot >> to the >>>>> touch. In June through August it is typically 100 to 118 F inside. >> My ev >>>>> has been garaged there for 5 1/2 years, 40k+ miles. I live in high >> desert >>>>> where the nights are typically 35 F lower than daytime highs, so the >>>>> highest >>>>> temperature the battery reaches just sitting in the garage is >> significantly >>>>> below the daytime high temperature in the garage since the cells have >>>>> significant heat capacity and are in insulated boxes. >>>>> >>>>> The pack has been up to 110 to 115 F a number of times in the hot >> months >>>>> after longer drives. Seems to just keep going. Each year I do a test >> drive >>>>> to discharge the pack to about 28% SoC, then floor the accelerator to >> draw >>>>> 3C from the pack and see if the LVC alarm on the minibms triggers. So >> far >>>>> it >>>>> has not. Range likely has decreased a bit, but this test indicates it >> has >>>>> not decreased all that much. My cells are LiFePO4, different than the >> Leaf, >>>>> but according to Dahn worse with regard to temperature effects, so I >> don't >>>>> think you need be too concerned. On the hottest days I sometimes park >> the >>>>> car in the shade of a tree rather than leave it in the garage. >>>>> >>>>> Winter brings the opposite problem, but I have Farnum heaters under >>>>> aluminum >>>>> sheet that the batteries sit on and 1/2" insulation in the boxes. >> Keeps >>>>> them at the set point of 65 F in the winter when it is plugged in in >> the >>>>> garage and above 50F if left parked outside for 4 - 5 hours. >>>>> >>>>> >>>>> >>>>> >>>>> >>>>> -- >>>>> View this message in context: >>>>> >> http://electric-vehicle-discussion-list.413529.n4.nabble.com/Success-tp4675905p4675945.html >>>>> Sent from the Electric Vehicle Discussion List mailing list archive at >>>>> Nabble.com. >>>>> _______________________________________________ >>>>> 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 >>>> >>>> michael.e.r...@gmail.com >>>> <michael.e.r...@gmail.com> >>>> -------------- next part -------------- >>>> An HTML attachment was scrubbed... >>>> URL: < >> http://lists.evdl.org/private.cgi/ev-evdl.org/attachments/20150601/5cb534fb/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) >>> >> > > > > -- > 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 > > michael.e.r...@gmail.com > <michael.e.r...@gmail.com> > -------------- next part -------------- > An HTML attachment was scrubbed... > URL: > <http://lists.evdl.org/private.cgi/ev-evdl.org/attachments/20150603/a9839402/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)
