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While waiting for the motor and adapter to arrive, I mocked up their relative position with a 9" dia plastic bucket down low in the engine bay. First appearances said I had a bunch of excess space for many battery cells.
I started with the use of US Postal Service flat rate boxes to approximate the size of Tesla 25V battery packs. Initially I had targeted 120 to 144 volt capacity while maintaining close to original weight distribution - an important consideration. That would mean 3-4 cells in front and two in back. That configuration would do the two things I didn't want - high center of gravity in front and chopping out the former gas tank hole in the trunk. I was also warned that the Tesla battery packs were trickier to adapt than the LFP cells.
So, I calculated out the number of CALB type cells needed to attain my voltage target to be 40 cells. I made blocks of wood to imitate the size of the LFP cells. No matter how I stacked them, I would be limited to maximum 24 in front and 16 in the rear = 128 volts. In front, I would likely have to chop some of the front grille area open, putting them further into the crash zone. In the rear, again I would have to enlarge the gas tank opening that I wanted to drop them into. But it was a better fit than Tesla packs and they would be new, unused and more stable. They also would not need water cooling.
When I started to build my EV, the salvage battery market was somewhat limited, while LFP cell options were becoming more numerous, less costly, and more dense - size was coming down and Amp hours were going up!
In the year of prep ahead of deciding on which way to go, the reality of my available space, including selected charging equipment, controller, and contactor/fuse boxes, became more evident as the size and locations became more fixed. I settled on 33 each EVE 280 amp hr LFP cells. These reduced numbers still calculated out to an approximate 100 mile range, and would fit available spaces, front and rear, without chopping into the car structure or body. While I had decided to wait until the last minute to get batteries to my shop, I had not waited to purchase and receive the charging equipment. This led to another problem...
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