If n-1 batteries is above the controller minimum voltage, just take the bad one out and drive on the rest, to go the mile -- -Chris
On July 26, 2016 1:25:26 PM CDT, Robert Bruninga via EV <[email protected]> wrote: >Now that is the answer I needed. That is, older batteries may top out >at >a charging voltage less than a new one, and so if the charger is not >very >smart, it never reaches the cutoff voltage it expects. Never tapers >the >current and never indicates Full... even though the battery has >accepted >all it is going to. > >Im just trying to get enough juice back into it so I can drive the 1 >mile >to where I store it Thanks, Bob > >-----Original Message----- >Subject: Re: [EVDL] Lead Acid question > >On 25 Jul 2016 at 11:55, Robert Bruninga via EV wrote: > >> Im charging my 10 Lead Acids one at a time with a common 10A car >> battery type charger. Usually they come from low to high on the >> "percent" meter and then when they get to 100%, an LED comes on and >> the current tapers to zero. > >> But I have one battery that seems to just stay at mid range and after >> 20 hours is not topping off. And battery is not excessively bubling >> nor is it showing much heat gain. > >Note that I am not an electrochemist, just someone who's used batteries >for quite a few years. There are other folks here with far more >experience and knowledge than I have, but none of them has answered >your >question as yet, so I'll take a run at it. :-\ > >First, one thing that makes remote diagnosis tough is that you haven't >told us anything about the charger. Automatic chargers' algorithms can >affect the symptoms you see with a problem battery. > >That said ... > >It's normal for batteries' maximum on-charge voltage to fall as they >age. >Many automatic chargers know naught of this; they treat all batteries >the >same regardless of age. They'll undercharge new batteries and/or >overcharge old ones. They may not shut off when they should. They may >claim a battery isn't charged when it's as full as it's ever going to >get. > >However, the fact that you're seeing this symptom with only one battery >in >your pack suggests to me that that battery might have at least one bad >cell. >If you can't get its voltage to rise above around 13 volts with the >charger charging it (not open circuit), and after a few hours of rest >if >falls to around 11 volts (open circuit), then that's probably what's >wrong. > >In spite of what the snake oil salesmen claim, there's no cure for >this, >short of replacing the battery. > >As I suggested above, at least in my experience, the way automatic >chargers behave can make it harder to diagnose battery problems, unless >you know a lot about batteries and the charger's design. Charging with >a >manual charger or a regulated power supply, and discharging with a 25 >to >75 amp load, should tell you much more about what's really going on in >that battery. > >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 >http://lists.evdl.org/listinfo.cgi/ev-evdl.org >Read EVAngel's EV News at http://evdl.org/evln/ Please discuss EV drag >racing at 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 >Read EVAngel's EV News at http://evdl.org/evln/ >Please discuss EV drag racing at 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 Read EVAngel's EV News at http://evdl.org/evln/ Please discuss EV drag racing at NEDRA (http://groups.yahoo.com/group/NEDRA)
