Here is one test unit available for Prius packs: http://www.go2hev.com/hybrid-vehicle-battery-testing-and-analysis-kit.html
The maker Automotive Research & Design (what an instructive name) does more than just produce this test unit - they do a lot of training of mechanics by various means. http://www.go2hev.com/home.html OEM cell test equipment seems to come from ARBIN http://www.arbin.com/ On Mon, Nov 17, 2014 at 2:29 PM, Michael Ross <[email protected]> wrote: > Lee said: The only way to know for sure is to TEST. Test each cell or > battery, and see what you've got. If they are all low in capacity, then > it's time to replace the pack. If only one or two are significantly worse > than the rest, replace them and keep going. :-) > > This was my assumption. I will be interested to see if the school or > Hybrid Shop goes to this much trouble. > > If we were to estimate the labor required to test a Prius pack - > what would that look like? Would it be any where near sat $1000? > > I would like to take a critical eye into these visits, but I have never > looked close or far at a Prius pack. > > mike > > On Mon, Nov 17, 2014 at 1:33 PM, Lee Hart via EV <[email protected]> > wrote: > >> EVDL Administrator via EV wrote: >> >>> Alas, any time you fix a declining EV battery by replacing the worst >>> cells >>> or blocks, rather than all of them, you have no way to know what other >>> cells >>> or blocks might turn toes up next week, next month, or next year. >>> >> >> That's true. However, it is also true that the one cell that failed may >> have been "infant mortality". It could have died young due to some quality >> defect or temporary abuse (like excessively discharging the pack, which >> killed the weakest cell). If you replace it, you can keep right on using >> the rest of the pack for an extended period. >> >> I've done what they describe with lead EV batteries, replacing blocks as >>> they fail. With that situation it's mostly a losing game, because once a >>> couple blocks die, the rest usually aren't far behind. >>> >> >> This is often true because the driver and the battery charger don't >> *know* there's a problem. For example, if one cell shorts, the charger >> blindly charges the remaining pack to the full voltage that was needed with >> all cells good. That overcharges the remaining good cells, driving them >> into an early grave. >> >> Coincidentally, this is a NiMH question I'm facing too. I have a 36v 10ah >>> NiMH e-bike battery here that's on its last legs. I've been debating >>> whether >>> to (a) replace just the bum cells and see how it goes, (b) replace all >>> the >>> cells, or (c) gut the battery and try lithium cells instead. >>> >> >> If the original cells were high quality, they would all have been well >> matched. When one of them fails, the rest may not be far behind because >> they are all so much alike. For example, I've tested Prius nimh modules; >> even my 10-year-old ones are as alike as peas in a pod. >> >> If the pack is made from el-cheapo cells with negligible quality control, >> you could easily have a few lemons that died young, and are making the >> whole pack look bad. For example, I tested a set of ten 12v 7ah batteries >> from an anonymous Chinese manufacturer in a UPS; 4 were junk, and the >> remaining 6 varied from 1.7ah to 4.2ah. I was able to replace the 5 worst, >> and keep using the remaining 5. >> >> The only way to know for sure is to TEST. Test each cell or battery, and >> see what you've got. If they are all low in capacity, then it's time to >> replace the pack. If only one or two are significantly worse than the rest, >> replace them and keep going. :-) >> -- >> Obsolete (Ob-so-LETE). Adjective. 1. Something that is simple, >> reliable, straightforward, readily available, easy to use, and >> affordable. 2. Not what the salesman wants you to buy. >> -- >> Lee Hart's EV projects are at http://www.sunrise-ev.com/LeesEVs.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) >> >> > > > -- > Put this question to yourself: should I use everyone else to attain > happiness, or should I help others gain happiness? > *Dalai Lama * > > Tell me what it is you plan to do > With your one wild and precious life? > Mary Oliver, "The summer day." > > 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) 550-2430 Land > (919) 576-0824 <https://www.google.com/voice/b/0?pli=1#phones> Google > Phone > (919) 631-1451 Cell > (919) 513-0418 Desk > > [email protected] > <[email protected]> > > > -- Put this question to yourself: should I use everyone else to attain happiness, or should I help others gain happiness? *Dalai Lama * Tell me what it is you plan to do With your one wild and precious life? Mary Oliver, "The summer day." 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) 550-2430 Land (919) 576-0824 <https://www.google.com/voice/b/0?pli=1#phones> Google Phone (919) 631-1451 Cell (919) 513-0418 Desk [email protected] <[email protected]> -------------- next part -------------- An HTML attachment was scrubbed... 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