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Old 03-01-2009, 08:12 PM   #1016 (permalink)
bennelson
EV test pilot
 
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Join Date: Jan 2008
Location: Oconomowoc, WI, USA
Posts: 4,435

Electric Cycle - '81 Kawasaki KZ440
90 day: 334.6 mpg (US)

S10 - '95 Chevy S10
90 day: 30.48 mpg (US)

Electro-Metro - '96 Ben Nelson's "Electro-Metro"
90 day: 129.81 mpg (US)

The Wife's Car - Plug-in Prius - '04 Toyota Prius
90 day: 78.16 mpg (US)
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Back Seat Battery Box!

hey EVeryone!

It was a great day. Today was another EV Build Day at Tom's.
(I forgot my camera at home, but did take photos with someone else's camera. I will host photos later.)

I towed the Metro into the city and got prime parking space in the heated garage.

I already had the "test hole" cut in the backseat, and showed Rich what I was planning on doing, and let him poke around in there and see how the suspension and other things lined up and may or may not interfere with the box.

Brian offered to donate his 36" by 30" by 20" machine case to my project to become the back seat battery box.

I LOVE the plasma cutter!!!!

We cut the entire box down to a 10.5 inch height. Tall enough for the batteries, including posts, plus a little more for insulation and wiggle room.

We then chopped the box down to a 15 inch depth, and left it the entire 36 inches wide. Since my batteries are 7 inches wide, 5 of them side-by-side is 35 inches, so the 36 inch width is perfect!

36 inches also EXACTLY clears between the rear swing arms.

We welded the cut-off part of the box to the section we were using to make the 5th side (the sixth, top side of the box is left open.) Then we used the plasma cutter to chop off the extra part.

This made a very nice 36" by 15" by 10.5" metal box. And it's solid, so there's plenty to weld to, and no concerns about cross-bracing. In fact, be can weld a solid seam all the way around the box to make the car even sturdier than before!

Again, the plasma cutter was used to cut the big hole through the back seat. We dropped the box through the hole, and then had to figure out height before tack welding it.

We ended up making it so the the BOTTOM of the box was pretty much even with the floor of the car. The box wasn't lower than anything else, so I am not too worried about speed bumps!

This does make the top of the box stick out about three inches ABOVE the front lip of the seat, but the bottom of the box is out of the way of the parking brake cables and brake lines.

Speaking of brake lines.....After being away from the car for a few minutes, Brian asked me if I wanted to know the good news, the good news, or the bad news.

Long story short, the brake lines are gone. Time for new ones. We didn't get TOO much brake fluid on the floor. Oh, did you know that brake fluid is flammable? Well it is. It can be started on fire by a plasma cutter, just in case you didn't know.

That's odd, we actually were joking about setting electric cars on fire earlier in the day. Don't worry, it was only a small fire, and quickly stomped out.

I have a long section of conduit running under the car from the spare tire well to the front. I needed to move it to make space for the battery box. To do that, I had to disconnect the front end of the battery cables, charging cables, and 120V cables. I pulled all the cables, threw them in the back, and removed the conduit.

We fit the box through the back seat hole (after several people doing Fred Flintstone impressions.) Rich tacked the box in with the welder. It's in there nice and solid now, although we will finish off with a solid weld all the way around, and some welding from the bottom too.

The top of the box sticks up roughly 3 inches from the sheet metal of the car. Since the foam of the back seat is 5 to 6 inches thick, I should be able to hollow it out to put the back seat back in. Also, that extra three inches makes the top of the box about even with the bottom of the "trunk" area. So, another thing I could do is cut some thin plywood to fit and cover the spare tire well and extend out over the battery box. The plywood would then be covered with some nice thin carpet, and form a large, flat cargo area, similar to a Honda Insight (the original one!, not the new one!)

I am not sure if I want to keep the back seat for "Looks" and "normalicy", or go with the big cargo area, which could look really cool too. It also might be neat for showing off the car. I could actually install plexiglass over the batteries, and have other components (charger?) in the spare tire well. I could normally have carpet over the top, but pull it off for displaying the car!

Anyways, I now need to replace the rear brakelines, pull all the batteries out of the back, install new conduit between the batt box and the front, figure out how to fit for batts in front! Oh criminy! That's a lot of work!

I feel very excited about the project again!

OOOh! Tom also had a couple of small DC/DC converters kicking around; 2 5 volters, and a 3.5V! They are a style that should be able to be run in series, which would make a 30 amp 13.5V output! Sounds like plenty for headlights to me! That would allow me to use a much smaller 12v battery! Might help free up some space under the hood!

With the cabling pulled, the car can no longer move under it's own power. Since I stripped out the insides, there's no driver seat either!

That's how I ended up being pushed backwards, down Tom's driveway to the road - quickly!

"That's odd", I remember thinking to myself when I pressed the brakes and the pedal sunk to the floor. "That's right, we did loose the brakes, didn't we.."

I yank the hand brake as the car flies towards the road, me sitting on the floor of the car, too short to see out the rear window.

Once traffic clears, the guys push me to the back of my truck to hitch up the tow bar and take off for the day.

Cut a hole in the car, lost the brakes, started a fire, and didn't die in a flaming wreck!

What will we do next time to top it!?



(I will post some photos of the batt box when next I have some time in daylight.)
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