Re: [EVDL] How crazy am I?
On 22 Jul 2014 at 10:24, Ben Goren via EV wrote: > Wikipedia says curb weight is 2,445. I don't see this ending up at 3,500 after > conversion...but I also like estimating pessimistically. I see that too. But that's probably for an early 170 six with 3-speed stick and no options. Remember, in those days, even a radio was optional. In the same article, I read 2570 lb for a 1965 6-cylinder, and 3000 lb for a "fully equipped" V8 model. That seems like more difference than I'd expect for a 260 or 289 vs a 170 or 200, but I suppose they'd have beefed up other drivetrain components. The designers were working this all out by hand - they had no computer modeling in those days. They also apparently had some early problems with excessive body flexing, so stiffening the body probably added some weight. > Another factor to consider is that while power capability varies by > design, as a general rule, smaller cells are usually capable of lower > power output. > Um. I was unaware that that was something that needed to be taken into > consideration. Is that a matter of heat dissipation, and therefore > something that'd get worse in summer and be helped with active cooling? > Or does it have more to do with chemistry, or...? It's a design decision, I guess. In lead batteries you're balancing cost, cycle life, specific power, and specific energy. You can't optimize for all of them at once. I would think that lithium battery designers make similar tradeoffs. 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 For EV drag racing discussion, please use NEDRA (http://groups.yahoo.com/group/NEDRA)
Re: [EVDL] Design News - Battery-Electric Vehicles: It's a Question of Trickle-Down
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Re: [EVDL] How crazy am I?
> > configuration, we now have 218mm (8.6") x 1100mm (43") x 567mm (22.3") > for a > > battery box about 11"h x 45"w x 24"d. > > ...or about one by two by four feet. > > > Would there > > be enough room for this battery in the forward part of the trunk, between > > the wheel wells and above the rear axle? > > Possibly...but something like that might make sense as a pair of, say, one > by two by two feet blocks at the outside edge of the trunk, or even four > one by one by two blocks at the four corners of the car -- the engine > compartment has lots of empty space in it. Or split the difference between > the pack sizes, or some other variation on the theme. > > Regardless, the math seems to show that the physical dimensions of the > batteries aren't going to be a show-stopper, which I think is the most > important thing for me to worry about with this type of exercise at this > stage. > > Thanks again for the help! > > b& > -- next part -- > A non-text attachment was scrubbed... > Name: signature.asc > Type: application/pgp-signature > Size: 801 bytes > Desc: Message signed with OpenPGP using GPGMail > URL: < > http://lists.evdl.org/private.cgi/ev-evdl.org/attachments/20140722/ee3b1147/attachment.pgp > > > ___ > 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) > > -- next part -- An HTML attachment was scrubbed... URL: <http://lists.evdl.org/private.cgi/ev-evdl.org/attachments/20140722/f1668da8/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)
[EVDL] Design News - Battery-Electric Vehicles: It's a Question of Trickle-Down
www.designnews.com/author.asp?section_id=1366&doc_id=274132&cid=nl.dn14&dfpPParams=ind_184,industry_auto,bid_318,aid_274132&dfpLayout=blog Dhar, who was instrumental in the development of the battery for GM's groundbreaking EV1, believes that the price of a 30-kWh battery needs to hit $5,000. That means pack costs must drop to about $160/kWh, a figure that is still not in sight. "It will happen," Dhar told us. "But it's not clear that it will happen any time in the next 10 years." ___ 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)
Re: [EVDL] How crazy am I?
On 07/22/2014 12:33 PM, John Lussmyer via EV wrote: Have you thought about Leaf modules? That's what I'm using in my truck. http://hybridautocenter.com/HAC4/index.php?option=com_hikashop&ctrl=product&task=show&cid=4&name=new-11kw-h-battery-block-182v-60ah&Itemid=605 -- Try my What are the BMS options for the Leaf modules? ___ 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)
Re: [EVDL] How crazy am I?
On Jul 22, 2014, at 1:20 AM, EVDL Administrator via EV wrote: > Another factor to consider is that while power capability varies by design, > as a general rule, smaller cells are usually capable of lower power output. Um. I was unaware that that was something that needed to be taken into consideration. Is that a matter of heat dissipation, and therefore something that'd get worse in summer and be helped with active cooling? Or does it have more to do with chemistry, or...? b& -- next part -- A non-text attachment was scrubbed... Name: signature.asc Type: application/pgp-signature Size: 801 bytes Desc: Message signed with OpenPGP using GPGMail URL: <http://lists.evdl.org/private.cgi/ev-evdl.org/attachments/20140722/4ab9662b/attachment.pgp> ___ 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)
Re: [EVDL] How crazy am I?
On Tue Jul 22 10:24:59 PDT 2014 ev@lists.evdl.org said: >> How about CALB? The smallest one EVSource sells (that's not an endorsement, >> it's just one place I found offering them online) is 40ah. > >That's actually what I was using for my own back-of-the-envelope calculations, >but from EVWest's site. Have you thought about Leaf modules? That's what I'm using in my truck. http://hybridautocenter.com/HAC4/index.php?option=com_hikashop&ctrl=product&task=show&cid=4&name=new-11kw-h-battery-block-182v-60ah&Itemid=605 -- Try my Sensible Email package! https://sourceforge.net/projects/sensibleemail/ ___ 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)
Re: [EVDL] How crazy am I?
On Jul 21, 2014, at 10:21 PM, EVDL Administrator via EV wrote: > On 21 Jul 2014 at 14:12, Ben Goren via EV wrote: > >> I'm really only looking for a battery pack big enough for local trips; >> a couple dozen miles would be plenty. I suspect that the smallest pack >> that puts out the necessary voltage is going to be just about the >> right size ... > > Hmm. Maybe. Let's do some math. Thanks -- this really, really helps! > You're leaving in all the ICE bits for a > car that will probably weigh in the 2800-3000lb range before conversion, > maybe 3500 or more after. Wikipedia says curb weight is 2,445. I don't see this ending up at 3,500 after conversion...but I also like estimating pessimistically. > You'll might also pass up the skinny LRR tires > for sticky high performance ones. Yes, likely -- especially if this winds up being the type of performance vehicle I suspect it might. I'm thinking bicycle tires on something with this much torque and power likely would only increase my chances for a Darwin award > How about CALB? The smallest one EVSource sells (that's not an endorsement, > it's just one place I found offering them online) is 40ah. That's actually what I was using for my own back-of-the-envelope calculations, but from EVWest's site. > Each cell is 181mm x 115mm x 46mm. Again allowing a couple mm per cell for > breathing room between (the lithium experts here can give you more info on > whether this is necessary), your battery is now 181mm (7.1") high x 585mm > (23") long x 432mm (17") wide. Again add at least 25-50mm (1-2") to each > dimension to allow for battery box sizing, to get to around 9"h x 25"l by > 19"w, maybe even a little higher to allow for installing a BMS. That's again about what I came up with. A banker's box is one of those cardboard boxes that acts as a portable filing cabinet, mostly to store documents in a warehouse. It's about 10" x 12" x 15" -- a bit smaller, but not hugely. > Now with 45 cells we're talking 5.8kWh and a practical range of 13 miles > with new cells, declining to perhaps 9.8 miles after a few years of use. > Still only about half what you want. (But can you live with it?) I had roughly guesstimated a bit less than twice that range...considering you're assuming worse efficiency than I had been guessing at, that puts the numbers in the same ballpark. Especially considering that press release posted here earlier this morning about, in that example, LG planning "200 mile" packs in a couple years, I'm starting to think that it might not be such a terrible idea to start with a smaller pack that's merely "good enough" and figure on upgrading as battery technology improves. Those 45 of those CALB 40 Ah batteries are going to cost about $2500. If I planned on replacing them in 4 - 5 years with something that cost as much but had significantly more capacity, that'd work out to about the cost of a tank of gas per month. If I could put those batteries to good use at their end of life (I'm guessing they wouldn't have much resale value), that'd further mitigate that cost. > Sticking with our 5 x 9 > configuration, we now have 218mm (8.6") x 1100mm (43") x 567mm (22.3") for a > battery box about 11"h x 45"w x 24"d. ...or about one by two by four feet. > Would there > be enough room for this battery in the forward part of the trunk, between > the wheel wells and above the rear axle? Possibly...but something like that might make sense as a pair of, say, one by two by two feet blocks at the outside edge of the trunk, or even four one by one by two blocks at the four corners of the car -- the engine compartment has lots of empty space in it. Or split the difference between the pack sizes, or some other variation on the theme. Regardless, the math seems to show that the physical dimensions of the batteries aren't going to be a show-stopper, which I think is the most important thing for me to worry about with this type of exercise at this stage. Thanks again for the help! b& -- next part -- A non-text attachment was scrubbed... Name: signature.asc Type: application/pgp-signature Size: 801 bytes Desc: Message signed with OpenPGP using GPGMail URL: <http://lists.evdl.org/private.cgi/ev-evdl.org/attachments/20140722/ee3b1147/attachment.pgp> ___ 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)
Re: [EVDL] crazy ?
I and I think we all, will be sorry to see you go. You bring some levity and logic to the EVDL. Dennis Lee Miles (EVprofessor) *Founder:**EV Tech. Institute Inc.** (www.evti.org <http://www.evti.org>) * *You Tube Video Link: http://youtu.be/T-FVjMRVLss <http://youtu.be/T-FVjMRVLss> * *E-Mail:* *evprofes...@evprofessor.com* *Phone #* *(863) 944-9913* in Central Florida (Office hours: 12:00 Noon to 10:00 pm, New York time) On Tue, Jul 22, 2014 at 10:03 AM, Electric Blue auto convertions via EV < ev@lists.evdl.org> wrote: > Maybe the best and most simple thing to do is buy a new hybrid. It may not > be worth the effort to try and make one your self, Net gain did have a > "drive shaft interrupter" system. I dont think George is doing that any > more. sales didnt make it profitable for him. and it would NEVER work on > FWD vehicles > > > On another note, after about 35 years of doing this I am going to hang it > up at the end of the year . My health and age is making it hard to keep > going on. Its been a hoot all these years > I enjoyed it . but its better to sell everything off and sit on the front > porch in my rocking chair and drool. LOLOL > -- next part -- > An HTML attachment was scrubbed... > URL: < > http://lists.evdl.org/private.cgi/ev-evdl.org/attachments/20140722/a89c3d3a/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) > > -- next part -- An HTML attachment was scrubbed... URL: <http://lists.evdl.org/private.cgi/ev-evdl.org/attachments/20140722/80f1cc07/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)
Re: [EVDL] Hybrid/Mustang
Perhaps we should view the hybrid as a crossover vehicle for those insecure individuals who are not ready to go BEV "all the way," (A "reluctant virgin" so to speak.) I would note that many drivers of hybrids get a BEV as their next car purchase. Demonstrating the validity of my premice. Dennis Lee Miles (EVprofessor) *Founder:**EV Tech. Institute Inc.** (www.evti.org <http://www.evti.org>) * *You Tube Video Link: http://youtu.be/T-FVjMRVLss <http://youtu.be/T-FVjMRVLss> * *E-Mail:* *evprofes...@evprofessor.com* *Phone #* *(863) 944-9913* in Central Florida (Office hours: 12:00 Noon to 10:00 pm, New York time) On Mon, Jul 21, 2014 at 9:54 PM, Steve Clunn via EV wrote: > About 10 years ago Net Gain was making a kit to do just this. > They had two motors that were 11 inch and also 6.7 specially developed > to have high torque and lower rpm. It would fit right in line with the > drive shaft. You cut the drive shaft and attach one end to the front > of the motor and the other into the back. Of course you have to have a > way for the drive shaft to expand and contract. Their idea was to make > it with a plug that would plug into the car's computer and would turn > the motor on and off at the appropriate time and be able to drive > around on battery power for short distances. They had a 72 V Alltrax > controller. I'm sure a lot of development time went into this to get > it to talk to the car's computer. Some nice idea but they > discontinued the program. That said there's nothing saying you > couldn't pick this idea backup. I worked on one of these setups > briefly with another company. I don't think it ever really workout as > well as they had hoped as it was a big truck and as you can imagine a > big truck with a 7200 volt 6 AGM batteries would not get you very far. > Today with the lithium batteries you could get a much larger pack and > much more distance. I've done a few of the drives haft modifications > on vehicles where we use Two 9 "s or one net gained 11. I found that > the price of drive shaft work varies quite a bit. Here in Oklahoma I > had a drive shaft shortened and then and new skyline put on, to match > the Transwarp net gain 9" motor and it was a little over $100 back in > Florida the same work at another shop cost over $300. I believe that > Net Gain still makes the 6.7 inch motor for this application. I am NOT > it Florida and I'm don't have a computer. If you need any information > on the 6.7 mention that Net Gain motor and Audrey can supply that for > you. > > -- > Steve Clunn > Merging the best of the past with > the best of the future. > www.Greenshedconversions.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) > > -- next part -- An HTML attachment was scrubbed... URL: <http://lists.evdl.org/private.cgi/ev-evdl.org/attachments/20140722/e9d30df9/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)
Re: [EVDL] How crazy am I?
On 07/22/2014 08:29 AM, Mike Nickerson via EV wrote: I would consider my ThunderSky cells as 1C normal draw with bursts of 2C or maybe a little more. I have rarely seen 3C even in the best conditions. If they are cold, don't even expect 2C. With my ~2008 vintage TS-LFP260s, I can pull at least 800 amps in warm conditions without creating low voltage events. I would guess well over 10 seconds though the limiting factor is how fast you end up going rather than voltage sag. At temperatures of around 40 deg and below, they do start alarming at around 1C, 200-300 amps. ___ 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)
Re: [EVDL] Hybrid
After I got done experimenting with my hybrid back in the 80's which was a General Electric DC 11 inch motor as a helper for hill climbing, my next project was to replace the transmission gears with a torque tube made by TCI.com who makes and modifies transmissions for racing. This drive tube bolts directly on to a engine crank or motor coupler that eliminates the a flywheel, clutch and pressure plate. In a automatic, it eliminates the flex wheel and torque converter, but requires a pre-pressure oil pump to reduce the thrust which can brake things. Testing first with a manual with a gear ratio of 1.0 to 1 connected to a differential with a 5.57:1 ratio which is a overall ratio of 1.0 x 5.57 = 5.57:1. Starting out in this gear resulted in 600 to 700 motor ampere with slow acceleration. I added another gear ratio of 1.76:1 by using the 2nd gear which now gives me 1.76 x 5.57 = 9.8 overall ratio which is just right for city driving at 25 mph at 200 motor amperes, which is the continuous ampere rating of a WarP 11 motor. There was still some thrust problems at starting out, but not as bad as the violent thrust I had in 1.0 x 5.57 overall ratio with a 500 to 600 motor ampere at startup. Next I wanted to see how a automatic transmission would work. TCI.com recommended to use a GM TH400 transmission with a manual valve body, that eliminates the vacuum modulator and governor. You then can shift it like a manual and select the gear ratios at the sweet spot of a engine or electric motor. For the WarP-11 motor, the sweet spot is about 1800 rpm. So when the motor rises to 1800 rpm, then shift into the next gear and shift again when the motor gets to 1800 rpm again. First tried this set up without a torque converter which resulted in a very violent thrust at start up at 1 rpm. This resulted in 700 to 800 motor ampere which blew the transmission oil out the vent tube on to the floor. TCI.com recommended to use a low rpm large diameter torque convertor with a 1.8 ratio. The starting ratio will give me about a 10.0:1 overall gear ratio which runs at the motor continuous motor ampere. The torque converter cushions the torque trust which varies in a ratio of 1.8:1 at 1 rpm to 1.0:1 at 1800 rpm. NOW!! the motor ampere at start up may be 100 motor ampere or less and seen it down to 50 motor ampere. It is now a very smooth acceleration up to the 1800 rpm sweet spot of the motor. Increase the range of the EV by about 25 percent or instead of 39.5 miles, it is about 50 miles at 50% SOC. This type of transmission modification allows to have 3 speeds manual and with the 1.8 ratio torque convertor, it varies in ratios between the manual shifts. Like having a 6 speed transmission. Roland - Original Message - From: Tom Mandera via EV<mailto:ev@lists.evdl.org> To: Electric Vehicle Discussion List<mailto:ev@lists.evdl.org> Sent: Tuesday, July 22, 2014 12:16 AM Subject: Re: [EVDL] Hybrid On the topic of a hybrid install.. on something with enough space (perhaps not a Mustang), how about a boring old 4x4 transfercase. Leave the ICE configuration alone. Attach your electric motor either directly, or via the driveshaft, to the front output of the transfer case. Leave it in 4-high, and you could even run the motor as a generator at times. Put the ICE transmission in neutral when driving with the electric. Or go back farther in time, and you can run dual rear outputs on a Dana 18, Dana 20, or NP205, putting the motor behind the transmission and under the bed of a mini truck. You would lose gear reduction with this setup, though you would have 2 non-syncromesh gears in Electric mode by shifting between 4 high and 4 low (unfortunately acting as an overdrive instead) Sent from my Samsung Galaxy Tab®4 -- next part -- An HTML attachment was scrubbed... URL: <http://lists.evdl.org/private.cgi/ev-evdl.org/attachments/20140722/70f68a9c/attachment.htm<http://lists.evdl.org/private.cgi/ev-evdl.org/attachments/20140722/70f68a9c/attachment.htm>> ___ UNSUBSCRIBE: http://www.evdl.org/help/index.html#usub<http://www.evdl.org/help/index.html#usub> http://lists.evdl.org/listinfo.cgi/ev-evdl.org<http://lists.evdl.org/listinfo.cgi/ev-evdl.org> For EV drag racing discussion, please use NEDRA (http://groups.yahoo.com/group/NEDRA<http://groups.yahoo.com/group/NEDRA>) -- next part -- An HTML attachment was scrubbed... URL: <http://lists.evdl.org/private.cgi/ev-evdl.org/attachments/20140722/7ef441fb/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)
[EVDL] The classic VW Beetle goes electric
1. The classic VW Beetle goes electric Posted by: "Remy Chevalier" electrifyingti...@hotmail.com cleannewworld Date: Mon Jul 21, 2014 2:07 pm ((PDT)) The classic VW Beetle goes electric By <mailto:peter.valdes-dap...@turner.com> Peter Valdes-Dapena <https://twitter.com/intent/user?screen_name=peterdrives> @peterdrives July 18, 2014 . . http://money.cnn.com/2014/07/17/autos/zelectric-bug-electric-vw-beetle This is from the ET List. Nice conversions. Lawrence Rhodes -- next part -- An HTML attachment was scrubbed... URL: <http://lists.evdl.org/private.cgi/ev-evdl.org/attachments/20140722/36af69ee/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)
[EVDL] crazy ?
Maybe the best and most simple thing to do is buy a new hybrid. It may not be worth the effort to try and make one your self, Net gain did have a "drive shaft interrupter" system. I dont think George is doing that any more. sales didnt make it profitable for him. and it would NEVER work on FWD vehicles On another note, after about 35 years of doing this I am going to hang it up at the end of the year . My health and age is making it hard to keep going on. Its been a hoot all these years I enjoyed it . but its better to sell everything off and sit on the front porch in my rocking chair and drool. LOLOL -- next part -- An HTML attachment was scrubbed... URL: <http://lists.evdl.org/private.cgi/ev-evdl.org/attachments/20140722/a89c3d3a/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)
Re: [EVDL] How crazy am I?
I assumed people know, but guess I should specifically point out that ThunderSky is the previous name for the company now known as Winston. I don't know how much their chemistry varies between the two company names. My cells are more than 4 years old, so it is quite possible for new cells to be improved over mine. Mike On July 22, 2014 2:20:42 AM MDT, EVDL Administrator via EV wrote: >Another factor to consider is that while power capability varies by >design, >as a general rule, smaller cells are usually capable of lower power >output. > >For example, the CALB 40ah cells I mentioned are rated for a maximum >discharge of 2C (80 amps). At 144v, 80a is 11.5kW. Allowing for >losses, >that's only about 12hp from your motor! > >Not being a lithium expert, I don't know how much more than this you >can >actually draw before voltage sag really kicks in. But I'm pretty sure >that >pushing them too hard will shorten their lives significantly. > >If you expect sporty, Mustang-y EV performance, but don't want to carry > >around much of a battery, you'll need to find some cells designed for >high >power. > >The 90ah Winstons I mentioned are rated for only 1C continuous, but >they say >you can draw 10C for 10 seconds. It looks like you then need to allow >at >least 50 seconds of either zero or much lower current for the cell to >recover (how often you can do this isn't clear from the spec). Other >folks >here may know how realistic this is, and/or have some recommendations >for >high power lithium cells. > >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 >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)
Re: [EVDL] How crazy am I?
I would consider my ThunderSky cells as 1C normal draw with bursts of 2C or maybe a little more. I have rarely seen 3C even in the best conditions. If they are cold, don't even expect 2C. They work OK, but they are not a high performance pack. Mike On July 22, 2014 2:20:42 AM MDT, EVDL Administrator via EV wrote: >Another factor to consider is that while power capability varies by >design, >as a general rule, smaller cells are usually capable of lower power >output. > >For example, the CALB 40ah cells I mentioned are rated for a maximum >discharge of 2C (80 amps). At 144v, 80a is 11.5kW. Allowing for >losses, >that's only about 12hp from your motor! > >Not being a lithium expert, I don't know how much more than this you >can >actually draw before voltage sag really kicks in. But I'm pretty sure >that >pushing them too hard will shorten their lives significantly. > >If you expect sporty, Mustang-y EV performance, but don't want to carry > >around much of a battery, you'll need to find some cells designed for >high >power. > >The 90ah Winstons I mentioned are rated for only 1C continuous, but >they say >you can draw 10C for 10 seconds. It looks like you then need to allow >at >least 50 seconds of either zero or much lower current for the cell to >recover (how often you can do this isn't clear from the spec). Other >folks >here may know how realistic this is, and/or have some recommendations >for >high power lithium cells. > >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 >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)
Re: [EVDL] How crazy am I?
The discharge rate of the cells should play into the calculations as well. If the cells have a 3C max rate, 45 90 ah cells could produce about 52 HP (270 amps max@144v), resulting in a somewhat underpowered vehicle. How much does exceeding the discharge rate reduce the life of the pack? Is there a discharge rate that, once passed, makes the pack subject to random cell failures (i.e. more than 10C will damage the internal structure of a certain brand cell )? Tom Keenan On Jul 21, 2014, at 11:21 PM, EVDL Administrator via EV wrote: > On 21 Jul 2014 at 14:12, Ben Goren via EV wrote: > >> I'm really only looking for a battery pack big enough for local trips; >> a couple dozen miles would be plenty. I suspect that the smallest pack >> that puts out the necessary voltage is going to be just about the >> right size ... > > Hmm. Maybe. Let's do some math. > > A typical subcompact conversion uses around 250 Wh/mi. (Some have done as > well as 150-160 Wh/mi, carefully driven.) You're not going to match that > with a heavier, less aerodynamic car that wasn't designed with fuel > efficiency in mind, however. > > What can you do? Well, in the EV Photo Album I found a '66 Mustang > conversion that does 375 Wh/mi. > > http://www.evalbum.com/733 > > Here's a '65 ragtop that does 330 Wh/mi. That sounds a little better. > > http://www.evalbum.com/2056 > > One other similar Mustang entry estimated his energy use as "at most 500 > Wh/mi," but we'll take that with a grain of salt that since he doesn't seem > to have measured it accurately yet. > > Now, these are BEV conversions. You're leaving in all the ICE bits for a > car that will probably weigh in the 2800-3000lb range before conversion, > maybe 3500 or more after. You'll might also pass up the skinny LRR tires > for sticky high performance ones. So let's be conservative (and assume you > probably won't drive like I do ;-) and allow 400 Wh/mi. > > You want about 25 miles of range. So you need 10 kWh, but you don't want to > size your battery to that. You probably want to not exceed 80% DOD for good > life, but let's say you're OK with giving up a little battery life, and go > to 90%. So you actually need a battery capacity of about 11.1kWh. > > Doing that with lead in the space you have is going to be a non-starter, so > I guess we'll go right to lithium. A LiFePO4 cell has a nominal voltage of > 3.2v. Let's say you're going to use a 144v drive system, so you'll need 45 > cells. (In a more reasonable world, you'd determine how much energy and > power you need, and size the battery from that. THEN you'd decide what > motor and controlller would work with that battery. However, we'll assume > for now that you've already chosen a motor and controller, because it makes > the calculations easier.) > > We'll start with, as you suggest, "the smallest pack that puts out the > necessary voltage." The laptop-size cells are obvously too small unless > you go to massive paralleling a la Tesla, so let's jump to something like > Headway 38140 cells. I'm no lithium expert, but I'd guess that these are > about the smallest lithium cells practical for an EV (and a pretty light one > at that). > > The 38140s are 12ah cells, 38mm in diameter and 152mm long. Because they're > cylindrical, packaging isn't optimum, but (allowing a little wiggle room) a > 5x9 matrix would be 152mm (6") high, 200mm (7.9") wide, and 360mm (14.2") > long. Your battery box will need to be at least 25-50mm (1-2") larger in > all dimensions than this, to allow for wiring, ventilation, and (in the > winter) insulation. So you're looking at maybe 8"h x 10"w x 16"l. I don't > know how that compares to a banker's box, not being familiar with such a > critter. > > Each cell is good for about 38.4 Wh, so 45 of them would be ... 1.73kWh. > Hmm. That would get you about 4.3 miles of range. We're going to need > something larger. > > How about CALB? The smallest one EVSource sells (that's not an endorsement, > it's just one place I found offering them online) is 40ah. > > Each cell is 181mm x 115mm x 46mm. Again allowing a couple mm per cell for > breathing room between (the lithium experts here can give you more info on > whether this is necessary), your battery is now 181mm (7.1") high x 585mm > (23") long x 432mm (17") wide. Again add at least 25-50mm (1-2") to each > dimension to allow for battery box sizing, to get to around 9"h x 25"l by > 19"w, maybe even a little higher to allow for installing a BMS. > > Now with 45 cells we're talking 5.8kWh and a practical range of 13 miles > with new cells, declining to perhaps 9.8 miles after a few years of use. > Still only about half what you want. (But can you live with it?) > > Let's see what we can do to get closer to your target range. The Winston WB- > LYP90AHA is a 90ah cell. This will give you nearly 13kWh for a practical > range of 29 miles, perhaps 22 miles as
Re: [EVDL] EVLN: Schaeffler sez 2speed-tranny improves EV-range/efficiency
It does tickle me seeing such a luminary engineering setup like Bosch making such a silly mistake after Tesla has 'been there, done that'. It may turn out well for them but it seems a bit arrogant when you consider how much a success Tesla has had after just 1/10 of the time all the big automakers have been around for, and yet 'they know better'! Well, it'll be interesting to see if it lasts or whether they'll go back to having a single speed transmission on the end. Of course, it could just be a cunning ploy to build some cash revenue onto their EVs. After all, it'll need *some* maintenance! MW On 21 Jul 2014, at 15:55, Bill Dube via EV wrote: > Remember that the early Teslas had a two-speed transmission that proved to be > a disaster. They cured the problems by simply removing the source of the > problem: The transmission. > > If you install proper motor cooling and controller cooling, and perhaps > upgrade the motor or controller, then the desire/need for a transmission > naturally goes away. > > There is really never a need for a transmission in a well-designed EV. It > adds complexity, cost, and inefficiency. > > It is a red flag to investors when a start-up EV company proposes using a > transmission. It shows they have not really done the modeling correctly, or > they have installed a mismatched drive system and are trying to "fix" it with > a transmission. > > Bill D. > > On 7/21/2014 7:44 AM, brucedp5 via EV wrote: >> >> Bosch sez Gear changes will soon be part of EVs >> >> http://ecomento.com/2014/07/14/prototype-golf-proves-gears-make-electric-cars-go-further/ >> Prototype Golf proves gears make electric cars go further >> July 14, 2014 – Stephen Edelstein >> >> [image >> http://cdn.ecomento.com/wp-content/uploads/2014/07/step2-electric-golf.jpg >> ] >> >> Thanks to their instantaneous torque delivery most electric cars get along >> with a single forward gear. BMW, Nissan, and Tesla all employ this strategy, >> yet German automotive supplier Schaeffler thinks more is better. >> >> The company entered its STEP2 prototype in the fifth Silvretta E-Rally in >> Montafon, Austria, to test a new two-speed transmission that it believes can >> improve the efficiency of electric cars. >> >> Schaeffler stripped the internal combustion powertrain from a Volkswagen >> Golf, adding a complete electric powertrain and the novel transmission, >> which features a low gear for traction and a high gear for higher-speed >> cruising. >> >> The company says the STEP2 has already achieved an efficiency improvement of >> around six percent over a comparable electric car in simulations and tests. >> That’s six percent more energy that can go towards increased range. >> >> Internal combustion-engined cars need a spread of gears to match road speed >> with engine speed, but since electric cars produce all of their power no >> matter what speed the engine is turning, multiple gears have largely been >> viewed as unnecessary. >> >> Schaeffler believes an additional gear will allow the motor to work less >> hard to propel the car at a given speed, improving efficiency. It’s like a >> riding a bicycle: a gear that works well for sustained speeds might require >> more effort from the rider when starting out. >> >> That makes for a tired cyclist, but also a less-efficient electric car. The >> harder the motor has to work, the more electricity is required to keep the >> car moving. >> >> The STEP2 doesn’t exactly put an abundance of power at the driver’s >> disposal. Its output is just 50 kilowatts (67hp) in continuous operation, or >> 70 kW (93.8hp) at peak. >> >> The Silvretta E-Rally is the perfect place to test this setup. Unlike >> conventional road rallies, where the object is to complete a set of stages >> in the shortest elapsed time, victory in the E-Rally goes to the team that >> finishes with the least amount of energy used. >> [© ecomento.com] >> >> >> >> http://www.fleetnews.co.uk/news/2014/7/14/gear-changes-will-soon-be-part-of-evs-says-bosch/52966/ >> Gear changes will soon be part of EVs, says Bosch >> 14/07/2014 >> >> Transmission technology will soon find its place in electric vehicles (EVs), >> just as it has in petrol and diesel vehicles, according to Bosch. >> >> Electric motors have no difficulty in running up to 20,000 revolutions per >> minute (rpm) – compared to petrol or diesel engines, which usually only run >> up to a maximum speed of around 9,000 rpm – and so can run in a single gear, >> without the need for a transmission. >> >> To think of transmission and electrification as opposites is a >> misconception. Whether you're talking about an electric drive or a petrol or >> diesel engine, the right transmission will make any engine more efficient. >> >> As electric vehicles become more popular, motorists are being introduced to >> automatic vehicles that do not use traditional transmission. >> >> Most electric vehicles effectively operate in one gear with
Re: [EVDL] How crazy am I?
Another factor to consider is that while power capability varies by design, as a general rule, smaller cells are usually capable of lower power output. For example, the CALB 40ah cells I mentioned are rated for a maximum discharge of 2C (80 amps). At 144v, 80a is 11.5kW. Allowing for losses, that's only about 12hp from your motor! Not being a lithium expert, I don't know how much more than this you can actually draw before voltage sag really kicks in. But I'm pretty sure that pushing them too hard will shorten their lives significantly. If you expect sporty, Mustang-y EV performance, but don't want to carry around much of a battery, you'll need to find some cells designed for high power. The 90ah Winstons I mentioned are rated for only 1C continuous, but they say you can draw 10C for 10 seconds. It looks like you then need to allow at least 50 seconds of either zero or much lower current for the cell to recover (how often you can do this isn't clear from the spec). Other folks here may know how realistic this is, and/or have some recommendations for high power lithium cells. 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 For EV drag racing discussion, please use NEDRA (http://groups.yahoo.com/group/NEDRA)
[EVDL] EVLN: Son Crashes Dad’s Tesla-S EV
http://www.autoevolution.com/news/tesla-model-s-accident-son-crashes-fathers-car-83969.html#comid26327 Tesla Model S Accident: Son Crashes Father’s Car by Andrei Tutu 16th July 2014 [image http://s1.cdn.autoevolution.com/images/news/tesla-model-s-accident-son-crashes-fathers-car-83969-7.jpg (Father’s Crashed Tesla-S) ] This month hasn’t been the best for the Tesla Model S, with drivers all across the world acting in the worst ways, from running from the police to confusing the two pedals, causing one Model S crash after another. Well, today we have yet another Model S accident that took place in the US. This time, an example of the vehicle was introduced to a set of trees, with the car suffering moderate damage, at least judging from what we can see in the adjacent images. The details of the crash are sketchy, but wreckedexotics writes the damage on the sedan is worth US$ 30,000 (EUR). It appears that a son was driving his father’s car, having possibly stolen the keys. The youngster didn’t manage to dig to deep into the driving range though, with the accident taking place some 10 yards (meters) away from the driveway where the Tesla had been peacefully resting. The driver accidentally pushed the throttle, with the instant electric torque working against the car on this occasion. The same reason is believed to be sitting behind the now famous crash that saw a Model S run into a dealership sign at the Tesla factory in [Fremont], California. Still, Tesla Model S “father and son” jobs haven’t always been this lousy. We’ll remind you that, back in 2012, such a team became the first to squeeze over 400 miles (km) of range out of a Model S. It’s just that the son, age 12, didn’t exactly drive the car, whereas our hero chose a different path. [© autoevolution.com] For all EVLN posts use: http://electric-vehicle-discussion-list.413529.n4.nabble.com/template/NamlServlet.jtp?macro=search_page&node=413529&query=evln&sort=date https://www.facebook.com/TheBetterRide/photos/a.558748940898635.1073741828.517202638386599/631644300275765/ EV-Test-Drivers get a $10 Gift-Card @Santana Row 7/27 San Jose, CA https://www.facebook.com/TheBetterRide/events http://www.thecarconnection.com/news/1093277_following-in-teslas-footsteps-bmw-offers-to-share-electric-car-technology Following In Tesla's Footsteps, BMW Offers To Share EV Technology http://smart-grid.tmcnet.com/news/2014/07/15/7923544.htm UQM motors and controllers in Zenith Commercial e-Van http://evfleetworld.co.uk/news/2014/Jul/Uruguays-UTE-adds-Renault-Kangoo-EVs-to-fleet/0438015442 30 Renault Kangoo EVs added to Uruguay's UTE Utility fleet ... http://www.autoblog.com.uy/2013/11/ute-compro-30-renault-kangoo-ze-para.html http://home.bt.com/lifestyle/motoring/motoringnews/can-you-c-the-mistake-11363918585900 Despite misspelled signage, it is a popular public Southwark, UK EVSE ... http://home.bt.com/images/road-marking-showing-misspelling-of-the-word-vehicles-in-southwark-london--photo-credit-swns-136391858465603901-140710165045.jpg + EVLN: LG Chem's 200mi packs are on-their-way for 2016 {brucedp.150m.com} -- View this message in context: http://electric-vehicle-discussion-list.413529.n4.nabble.com/EVLN-Son-Crashes-Dad-s-Tesla-S-EV-tp4670460.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)
[EVDL] EVLN: LG Chem's 200mi packs are on-their-way for 2016
'GM CEO sez a future 200mi GM EV will fight a ~$35k 200mi Tesla-3 EV' http://transportevolved.com/2014/07/21/lg-chem-200-mile-batteries-way-2016/ LG Chem: 200-Mile Batteries on Their Way for 2016 July 21, 2014 By Nikki Gordon-Bloomfield [images http://media.transportevolved.com/wp-content/uploads/2014/05/GMBatteryBrownstown06.jpg LG Chem currently provides battery packs to Chevrolet for use in its electric cars http://media.transportevolved.com/wp-content/uploads/2014/04/GMBatteryLabExpansionOpens02-medium.jpg GM’s future electric vehicle plans include a 200-mile electric car. ] In the battle for electric car range supremacy, only Tesla’s all-electric Model S sedan can currently manage more than 200 miles on a single charge, thanks in part to its massive 60 or 85 kilowatt-hour lithium-ion battery pack. Come 2016 however, says South Korean battery manufacturer LG Chem, it will be suppling 200-mile battery packs to one of its electric car customers. Who that customer is remains a mystery. Talking with Reuters on Friday, LG Chem’s Chief Financial Officer Cho Suk-jeh promised the battery manufacturer’s second generation lithium-ion battery pack would deliver a massive improvement of range on its current first-generation battery packs. An improvement which could make travelling 200 miles or more on a single charge something that every new electric car was capable of, not just expensive luxury cars like the Tesla Model S. The breakthrough in technology between the first and second generation of LG Chem’s battery cells lies in the energy density of the cells. The energy density of lithium-ion battery packs — how much energy you can store per unit mass — has improved dramatically over the past five years. The more energy stored per unit mass, the larger a battery pack’s capacity is for a given size. The larger the capacity, the longer the range. Currently, LG Chem provides battery cells to General Motors for its Volt [pih], and to Renault for its Zoe supermini and Twizy city quadricycle [EVs]. While LG Chem does provide battery packs to other clients too — including Hyundai for use in its hybrid cars and to Ford for its plug-in cars — we’d guess that both GM and Renault will be at the top of the list of buyers for the new technology. Since neither Suk-jeh nor LG Chem has officially named who will get the new battery, we can’t say for sure who the first 200-mile battery packs will go to. We do know however that GM CEO Dan Akerson has previously promised GM would be bringing a 200-mile EV to market some time around 2016, so we’re pretty confident GM is going to be one of probably many customers for the new pack. The question we’re all eager to have answered though is this: how much will a 200-mile battery pack cost? [© transportevolved.com] ... http://www.torquenews.com/2250/rumored-200-mile-ev-confirmed-be-way-2016-who-will-make-it Rumored 200-mile EV confirmed to be on the way for 2016 – but who will make it? By Luke Ottaway 2014-07-20 ... http://ecomento.com/2014/07/21/lg-chem-targets-200-mile-electric-car-range-by-2016/ LG Chem targets 200-mile electric car range by 2016 July 21, 2014 – Richard Lane ... http://www.autonews.com/article/20140718/OEM10/140719842/lg-chem-targets-ev-batteries-with-range-of-more-than-200-miles-in LG Chem targets EV batteries with range of more than 200 miles in 2016 July 18, 2014 For all EVLN posts use: http://electric-vehicle-discussion-list.413529.n4.nabble.com/template/NamlServlet.jtp?macro=search_page&node=413529&query=evln&sort=date https://www.facebook.com/TheBetterRide/photos/a.558748940898635.1073741828.517202638386599/631644300275765/ EV-Test-Drivers get a $10 Gift-Card @Santana Row 7/27 San Jose, CA https://www.facebook.com/TheBetterRide/events http://www.thecarconnection.com/news/1093277_following-in-teslas-footsteps-bmw-offers-to-share-electric-car-technology Following In Tesla's Footsteps, BMW Offers To Share EV Technology http://smart-grid.tmcnet.com/news/2014/07/15/7923544.htm UQM motors and controllers in Zenith Commercial e-Van http://evfleetworld.co.uk/news/2014/Jul/Uruguays-UTE-adds-Renault-Kangoo-EVs-to-fleet/0438015442 30 Renault Kangoo EVs added to Uruguay's UTE Utility fleet ... http://www.autoblog.com.uy/2013/11/ute-compro-30-renault-kangoo-ze-para.html http://home.bt.com/lifestyle/motoring/motoringnews/can-you-c-the-mistake-11363918585900 Despite misspelled signage, it is a popular public Southwark, UK EVSE ... http://home.bt.com/images/road-marking-showing-misspelling-of-the-word-vehicles-in-southwark-london--photo-credit-swns-136391858465603901-140710165045.jpg + EVLN: Son Crashes Dad’s Tesla-S EV {brucedp.150m.com} -- View this message in context: http://electric-vehicle-discussion-list.413529.n4.nabble.com/EVLN-LG-Chem-s-200mi-packs-are-on-their-way-for-2016-tp4670459.html Sent from the Electric Vehicle Discussion List mailing list archive at Nabble.com. ___ UNSUBSCRIBE: http://w
Re: [EVDL] EVLN: BMW&Daimler developing 3-Hour Wireless Inductive EVSE for i3 EV
Dear David, I was a teacher in a juvenile detention center back in 2000 to 2002, and they taught me a lot. the gang members teach each other, so after the first one or two who find the wire un-sell-able, they won't steal it because there is no payoff for the risk.. A dumb thief does not have a long career and they spend a lot of time in the barbed wire hotel, "Jail." Dennis Lee Miles (EVprofessor) *Founder:**EV Tech. Institute Inc.** (www.evti.org <http://www.evti.org>) * *E-Mail:* *evprofes...@evprofessor.com* *Phone #* *(863) 944-9913* in Central Florida (Office hours: 12:00 Noon to 10:00 pm, New York time) On Tue, Jul 22, 2014 at 1:21 AM, EVDL Administrator via EV < ev@lists.evdl.org> wrote: > On 21 Jul 2014 at 4:20, Dennis Miles via EV wrote: > > > Or use copper plated aluminum wire as it is not worth nearly so much > > for metal scrap... each strand of the aluminum is coated with copper, > > they are nearly useless for recycling and that means they won't be > > stolen, but they work for electrical cords. > > The crooks won't know that until they try to sell it. By then they'll have > destroyed the charger. True, those bad guys won't steal the same stuff > again, but someone else will, and on and on ... > > 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 > For EV drag racing discussion, please use NEDRA ( > http://groups.yahoo.com/group/NEDRA) > > -- next part -- An HTML attachment was scrubbed... URL: <http://lists.evdl.org/private.cgi/ev-evdl.org/attachments/20140722/729ecc0c/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)
Re: [EVDL] How crazy am I?
David, I can corroborate your numbers on pack sizing. You pretty much summed up my conversion. I have 45 cells of ThunderSky 100Ah cells in a Honda del Sol for a nominal 144V pack and 13 kWh. In that car, I have a 50 mile range (barely). When new, I drove it 46 miles without issues, but I wouldn't try that on a regular basis. The car weighs 2550 pounds after electric conversion. I need a little more than 250 wh/mile with LRR tires and fairly conservative driving. >From my experience, I would say your estimates for a hybrid conversion are >quite close. My pack takes up about 1/2 the trunk (20 cells in 2 rows of 10) and two places under the hood (10 cells in front of the grill and 15 cells in front of the firewall along with the charger). See www.evalbum.com/2778 for more details and pictures. Mike On July 21, 2014 11:21:14 PM MDT, EVDL Administrator via EV wrote: >On 21 Jul 2014 at 14:12, Ben Goren via EV wrote: > >> I'm really only looking for a battery pack big enough for local >trips; >> a couple dozen miles would be plenty. I suspect that the smallest >pack >> that puts out the necessary voltage is going to be just about the >> right size ... > >Hmm. Maybe. Let's do some math. > >A typical subcompact conversion uses around 250 Wh/mi. (Some have done >as >well as 150-160 Wh/mi, carefully driven.) You're not going to match >that >with a heavier, less aerodynamic car that wasn't designed with fuel >efficiency in mind, however. > >What can you do? Well, in the EV Photo Album I found a '66 Mustang >conversion that does 375 Wh/mi. > >http://www.evalbum.com/733 > >Here's a '65 ragtop that does 330 Wh/mi. That sounds a little better. > >http://www.evalbum.com/2056 > >One other similar Mustang entry estimated his energy use as "at most >500 >Wh/mi," but we'll take that with a grain of salt that since he doesn't >seem >to have measured it accurately yet. > >Now, these are BEV conversions. You're leaving in all the ICE bits for >a >car that will probably weigh in the 2800-3000lb range before >conversion, >maybe 3500 or more after. You'll might also pass up the skinny LRR >tires >for sticky high performance ones. So let's be conservative (and assume >you >probably won't drive like I do ;-) and allow 400 Wh/mi. > >You want about 25 miles of range. So you need 10 kWh, but you don't >want to >size your battery to that. You probably want to not exceed 80% DOD for >good >life, but let's say you're OK with giving up a little battery life, and >go >to 90%. So you actually need a battery capacity of about 11.1kWh. > >Doing that with lead in the space you have is going to be a >non-starter, so >I guess we'll go right to lithium. A LiFePO4 cell has a nominal >voltage of >3.2v. Let's say you're going to use a 144v drive system, so you'll >need 45 >cells. (In a more reasonable world, you'd determine how much energy >and >power you need, and size the battery from that. THEN you'd decide what > >motor and controlller would work with that battery. However, we'll >assume >for now that you've already chosen a motor and controller, because it >makes >the calculations easier.) > >We'll start with, as you suggest, "the smallest pack that puts out the >necessary voltage." The laptop-size cells are obvously too small >unless >you go to massive paralleling a la Tesla, so let's jump to something >like >Headway 38140 cells. I'm no lithium expert, but I'd guess that these >are >about the smallest lithium cells practical for an EV (and a pretty >light one >at that). > >The 38140s are 12ah cells, 38mm in diameter and 152mm long. Because >they're >cylindrical, packaging isn't optimum, but (allowing a little wiggle >room) a >5x9 matrix would be 152mm (6") high, 200mm (7.9") wide, and 360mm >(14.2") >long. Your battery box will need to be at least 25-50mm (1-2") larger >in >all dimensions than this, to allow for wiring, ventilation, and (in the > >winter) insulation. So you're looking at maybe 8"h x 10"w x 16"l. I >don't >know how that compares to a banker's box, not being familiar with such >a >critter. > >Each cell is good for about 38.4 Wh, so 45 of them would be ... >1.73kWh. >Hmm. That would get you about 4.3 miles of range. We're going to need >something larger. > >How about CALB? The smallest one EVSource sells (that's not an >endorsement, >it's just one place I found offering them online) is 40ah. > >Each cell is 181mm x 115mm x 46mm. Again allowing a couple mm per cell >for >breathing room between (the lithium experts here can give you more info >on >whether this is necessary), your battery is now 181mm (7.1") high x >585mm >(23") long x 432mm (17") wide. Again add at least 25-50mm (1-2") to >each >dimension to allow for battery box sizing, to get to around 9"h x 25"l >by >19"w, maybe even a little higher to allow for installing a BMS. > >Now with 45 cells we're talking 5.8kWh and a practical range of 13 >miles >with new cells, declining to