Hi Michael, You might find it helpful to put a Watthour meter between your mains socket and charger as these are very cheap and reasonably accurate. Whilst it will not take into account the efficiency losses in the charger and battery pack (no more than 10% and possibly less than 5%), it will at least give you some idea of how accurate your MiniEV Display is. Besides, there is no getting around these losses so really you (and everyone else) should be quoting your Wh/mile figure including them anyway... IMO!
Something else worth mentioning, as with Dan P's Jeep, I feel you may be exercising your 100Ah LiOn cells a bit too hard for good longevity. I understand entirely that with the price of Lithium still high you are a bit stuck in your cell choice but 160Ah would have been a more suitable choice, plus, of course, you'd get much better range. I would try to avoid discharging them below 60 or 70% to try and make up for stressing them at relatively high 'C' (discharge rate relative to their capacity) continuous discharge. It will be interesting to see how they do in time. Regards, Martin Winlow Herts, UK http://www.evalbum.com/2092 www.winlow.co.uk On 9 Feb 2013, at 23:23, Mike Beem wrote: > I had the opportunity today to take the Escort EV ( > http://www.evalbum.com/4181) for the longest sustained trip I have made in > the 14 months since I changed to Lithium. I have not re-balanced since I > put this pack on the road in December, 2012; recent checks at full charge > showed all cells within 0.02v, and at 70% discharge within 0.04v of each > other, so I consider the pack to being staying balanced. If I am missing > something here, please speak up. > After charging Thursday night, I ran the charger again Friday until the > mini BMS shut it down, with me watching. Pack voltage ran up to 146v, all > red led's were well lit, so I know that the pack was as fully charged as I > was going to get it. I didn't need to go anywhere yesterday, so it sat > without being turned on at all. My drive today was country roads, up and > down hills, frequent stops and subsequent acceleration up to 50-55mph. When > I got home and looked at my usage according to the Mini EV Display, I had > used either 306 Watt hours per mile, or 2.273 Amp hours per mile, which is > lower than my normal driving into town/in-town driving going to work, etc, > which seems to average (Winter temps) 2.4-2.77 Ah/mile. > > Are these numbers reasonable? This EV is *totally* different from my > previous +/- 200 volt AGM powered with reptilian controllers (T-Rex, > Godzilla) EV's, one of which had the license*QUICKEV*, so I still am > learning a new driving style. I was getting up to 55 from traffic lights as > slowly as I felt I could get away with depending on the cars behind me, > keeping the amps below 200 whenever possible, and staying to the right when > there was a passing lane. The real number I came up with today for Winter > driving without using the heater based on what I experienced is that I have > a real 40 mile range, which is what I estimated and aimed for when I > changed to lithium at the end of 2011. The pack is 40 CALB 100 Ah cells. > I think I may need to re-calibrate EV Display; I have it set for 20% for > minimum SOC, full pack @ 100 Ah, 13500 Wh. > Thanks for helping me drive electric! > Michael B -------------- next part -------------- An HTML attachment was scrubbed... URL: <http://lists.evdl.org/private.cgi/ev-evdl.org/attachments/20130210/8685beaa/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)
