I finally have the car running again! I got the controller back from Netgain Controls with an upgraded motherboard to fix some issues I was seeing. My Interface Module was also fixed to report the accurate voltage.<\/p>\n
Here’s some data from the drive home as logged by the controller.<\/p>\n
Total amp-hours consumed: 41.955 ah<\/p>\n
Watt-hours, based on my 48 cell pack at 3.2v nominal, for 153.4v: 6444 watt-hours<\/p>\n
Watts per mile, based on the 20-mile drive home, including highway 17 at 50-55 mph: 322.2 watts\/mile.<\/p>\n
That is what the controller is consuming; the battery has some extra draw to maintain the 12v battery via the DC-DC converter.<\/p>\n
Let’s consider 322 watt-hours\/mile as the average, although that was fairly conservative driving (not punching the throttle at lights, and coasting to a stop when I could).<\/p>\n
The pack has: 48cells*3.2v*200ah = 30720 watts (30.7 kilowatts) of energy. At 322 watts\/mile that would give a range of 95 miles. Give that I shouldn’t take the batteries lower than 20% depth of discharge (DOD) to get a high cycle life (and ensure I don’t kill cells), that give me a safe usable range of: 76 miles. Say 75 to be safe.<\/p>\n
So, my range with my driving conditions is 75 miles. I could eek out 10 more if I really had to.<\/p>\n
Here’s a graph of the voltage as I drove home. About 2\/3rds the way through you can see it dropped quite a bit; that was driving up Highway 17:<\/p>\n
Here’s a graph of the battery amperage taken by the controller. You can see the spike when I drove up highway 17 (again, 2\/rds the way home). At the end is a spike to almost 600 amps as I hit the throttle all the way for fun at the apex of the hill before coasting downwards to my house:<\/p>\n![\"Screen](\"http:\/\/www.corbinstreehouse.com\/blog\/wp-content\/uploads\/2011\/03\/Screen-shot-2011-03-08-at-7.53.10-PM.png\")
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