---------------------------------------- > From: hoegb...@hotmail.com > To: ev@lists.evdl.org > Subject: RE: [EVDL] Did Tesla steal my battery design? > Date: Tue, 18 Jun 2013 21:23:44 +0200 > > ---------------------------------------- >> Date: Tue, 18 Jun 2013 08:25:40 -0700 >> From: crui...@live.com >> To: ev@lists.evdl.org >> Subject: [EVDL] Did Tesla steal my battery design? >> >> In 2004 I converted a 1970 VW, designed a 32kw battery pack using 8k >> Panasonic 18650 Li-ion cells, with a range of almost 200 miles. You can see >> a U Tube interview listed below. Tesla later adopted the same cell to use in >> their roaster and now the Tesla S and Tesla X. I am sure their design is >> much superior than mine was, but I guess I can say that I was the first to >> use Li-ion to power a EV on the city streets. >> >> http://www.youtube.com/watch?v=xVlsSAZPvU8 > > > Cool! > I have a -66 Bug and will convert it some day when I find money.. in 50 years > or so.. > > But about the pack > What is the capacity today of the cells? % left? > have you done any discharge test lately on the pack? Graph? > > Did you use some kind of "protected" cells with internal "bms"? > > /John
Here is a good page from some guy that show the internals of a protected cell: http://www.lygte-info.dk/info/battery%20protection%20UK.html I guess this is the source of the Teslas "brick" problem, if they forgot to ad some trickle charging ways up to 2.6-2.x volt at each stage... But if this was the source of the problem, then it should also be easy to fix it? So I guess its not.. -But IF.. I dream on .. I guess one would just have to charge the pack at each and every cell sheets levels in the BMS-connection-leeds for all 11 sheets/modules, just enough to kick all the protection back up live again, to "connect" that cells in each series string, right?? How many cells in paralell in each "sheet"? 225kw peak engine(wheel?)output / 53kWh pack +losses and voltage sag, hmm. is this correct?? wow, over 5C peak.. :-) 53 000 Wh & 375V nominal 375V so I guess 104 cells = 3.6V 104*11 sheets *6Cells in paralell = 6864 cells, is that the correct number? then I assume about 280 kW from the battery / "375"Volt = more than 750 Amps /11sheets /6p = 11-12 Amps per cell, and if it is only 53kWh at 100%DOD it would be.. About.. 7.7Wh/cell in this guessing I guess.. So?? is it really a 2.1-2.2 Ah cells only?, hmm.. then 5-6C peak ? if it was energy cells, then it might be about 3.6 to 4C peak? But if so, it should not be 100% DOD in the 53kWh spec! If I guess at a 2.7Ah(?) or so,, medium power cell(?), *3.6V(?) *6864 cells *80% DOD(?) = 53 Kwh :-) // IguessAlot[tm] _______________________________________________ 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)
