Man, I'm really glad I chose a truck because there's more possibilities for battery locations! A friend of mine is converting a Pontiac Fiero and has had a tough time finding space for all those batteries. It can be done though and he's done a superb job utilizing every nook and cranny.
I put 20 batteries behind the cab, 10 in a box behind the rear axle where the spare tire was and 10 between the rear axle and the back of the cab. These boxes are made from 14 gage steel , folded and MIG welded at the seams. They are mounted between the frame channels and become part of the structure of the frame. Several of the original frame channel cross-members were removed to make space for and be replaced by the battery boxes. The front box originally had 12 batteries but I had a clearance problem over the drive shaft and differential pinion shaft flange so I had to raise the floor of the box in that area and loose space for two of the batteries. That took care of the flange interfearance but the drive shaft would still sometimes interfere with the bottom of the box when I would hit a pot hole under high driveline torque conditions. To fix this I added inch and a half high lift blocks between the springs and rear axle. No more problems now!
In the picture on the left, you can see how the boxes fit between the frame channels and notice the reinforcing webs that run transverse. These run between the Optima Yellow Tops and really stiffen the boxes and frame assembly. The batteries are held down with a 3/8" thick aluminum block with two 5/16" tapped holes. The blocks are between two batteries and bolts come from below, through the floor of the box, through holes in the base of the Optima and into the tapped hole in the block. You might be thinking, "man that's a lot of little blocks" and well ...... it is! But it works and is a very clean setup. The boxes are covered with 1/8" clear acrylic.
The Ford Ranger was probably the worst choice for a conversion vehicle from the standpoint that the frame channels have the narrowest spacing of any mini pickup I've seen. Also one shock is in front of the rear axle and one is behind. Plus, the anti sway bar was in my way!. All this didn't deter me. I found a way to fit everything in by moving the right shock behind the axle to match the left and flipped the anti-sway bar to the rear. It all fits!
There are 6 more batteries under the cab. As the picture on the left shows, there are 3 Optimas laying on their sides on each side of the driveline with the terminals facing each other. The center picture is a close-up of a "buddy pair" on the left side of the truck just behind the transmission. If you look closely, jusb to the left of the U-joint is the Albright disconnect switch breaking the most negative side of the pack mounted to the underside of the cab floor. I covered the underbelly with .093" ABS to keep the batteries clean and make the truck more aerodynamic. The picture on the right shows the center panel in place as viewed from the rear of the truck.
Traction pack cabling was made from 2/0 welding cable and Quick cable crimp connectors. I built a hydraulic press and a crimping die shown in the picture in the above right to crimp the cable connections which worked great. The die design was based on Bill Dube's technique of using a hex socket that you split in half. Between two of my EV buddies and I, we made over 300 crimps with consistent results and crimp resistances of under .0001 ohms. Sure saved a lot of elbow grease!