My first run to an empty pack - DIY Electric Car Forums
Go Back  

DIY Electric Car Forums > EV Conversions and Builds > All EV Conversions and Builds

Register Blogs FAQ Members List Social Groups Calendar Search Today's Posts Mark Forums Read

Reply
 
Thread Tools Display Modes
  #1  
Old 04-10-2012, 09:57 PM
fb_bf's Avatar
fb_bf fb_bf is offline
Member
 
Join Date: Jul 2011
Location: Longmont, Colorado
Posts: 37
fb_bf is on a distinguished road
Default My first run to an empty pack

I just finished finding my true range for the first time. I haven't charged my car since last Wednesday. I've been driving to work and back (10 miles), and to the driving range, again in town. I got home with the odometer reading 67 miles, and I thought I would drive close to my house until my BMS told me I had a cell too low. I drove a route that was mostly 40 to 45 mph, and probably had about 20 stops and starts. I ended up with 101 miles!!! My odometer is off slightly so I think it was really 112 when all done. When the BMS said I had used 80% of the pack, my batteries still read 3.25 volts. I have 38 160AH Thundersky cells in my car. I had my Elithion BMS set up to post a low battery fault at 2.7 volts. I have that signal connected to a light in my dash and to my Soliton Jr. Controller. I had set up the controller so that if the warning light came on, it would only deliver 50 amps. It all worked fine. I was able to get another 3.5 miles out of the car, and there was probably a couple of miles still left. At rest my low cells were reading 2.96 volts. With a 50 amp load they would sag to 2.8 volts.
My cells came from Evolve electrics here in Boulder. They had these used cells from a university that only had 20 cycles on them. When I heard that, I thought these might be a great deal because any really bad cells had probably been culled. I think I was correct. I definitely have a well balanced pack. The highest resting voltage I saw was 3.09 volts. So I think my lightened flywheel, weight reduced bumper, and loosing the luggage rack have paid off.
As you can tell, I'm really excited. I have solar panels on my house, and I looked at my production today. It was 42 Kwh. It's a good time of year for solar. That means in half a day of solar production I can drive 110 miles. (19.6 Kwh pack)
__________________

Frank Bernett -- '77 MG Midget, 19.6 Kwh LiFePo, Warp 9 Impulse, Soliton Jr., Elithion BMS
www.electricmgmidget.com
Reply With Quote
Sponsored Links
Advertisement
 
  #2  
Old 04-10-2012, 11:43 PM
gottdi
Guest
 
Posts: n/a
Default Re: My first run to an empty pack

Awesome news Frank. Nice to see you have a 100 mile range vehicle. That's better than my Leaf. Great work on the build.

Pete
Reply With Quote
  #3  
Old 04-11-2012, 09:41 AM
dladd dladd is offline
Senior Member
 
Join Date: Jun 2011
Location: Novato, California
Posts: 684
dladd is on a distinguished road
Default Re: My first run to an empty pack

Nice build, that is awesome! I can only dream of that kind of efficiency.

home solar is on my summer list, looking forward to that step for sure.
__________________
1995 Saturn SL2 ev conversion
Reply With Quote
  #4  
Old 04-11-2012, 10:42 AM
skooler's Avatar
skooler skooler is offline
Administrator
 
Join Date: Mar 2011
Location: Worcestershire, UK
Posts: 1,085
skooler is on a distinguished road
Default Re: My first run to an empty pack

Sweet work!

So what do you think you are getting for WH/mile?

Cheers,

Mike
Reply With Quote
  #5  
Old 04-11-2012, 01:04 PM
fb_bf's Avatar
fb_bf fb_bf is offline
Member
 
Join Date: Jul 2011
Location: Longmont, Colorado
Posts: 37
fb_bf is on a distinguished road
Default Re: My first run to an empty pack

Quote:
Originally Posted by skooler View Post
Sweet work!

So what do you think you are getting for WH/mile?

Cheers,

Mike
My latest testing using my Soliton Jr. logging showed 183wh/m at 50mph. My commute calculations where estimating at about 196wh/mile. If I use the 19.6Kw pack capacity with 112 miles I get 175 wh/m. I suspect that my actual pack capacity is higher than 19.6Kwh. Remember that I'm driving around at 5000ft which has an air density equal to 85% of sea-level. This is distinct advantage for altitude. Normally ICE cars don't perform as well at altitude due to the lack of oxygen, but for electrics, it's a benefit.
__________________

Frank Bernett -- '77 MG Midget, 19.6 Kwh LiFePo, Warp 9 Impulse, Soliton Jr., Elithion BMS
www.electricmgmidget.com
Reply With Quote
Reply

Share or Bookmark this

Thread Tools
Display Modes

Posting Rules
You may not post new threads
You may not post replies
You may not post attachments
You may not edit your posts

BB code is On
Smilies are On
[IMG] code is On
HTML code is Off

Forum Jump

 
Support DIY Electric Car
Sponsors

All times are GMT -6. The time now is 01:27 AM.


Powered by vBulletin® Version 3.8.7
Copyright ©2000 - 2014, vBulletin Solutions, Inc.

Ad Management by RedTyger