Hello to All,
Thanks for the interest. Yes, the flat shape of the cells certainly helps
in the 'find places to put all of them' department! To be honest, it's quite a challenge to find the space for 985 ls. of cells - which when installed including the actually module cases, conductors, and BMS will be 1080 lbs.
I 'had' wanted to simply make three, 318V, 75 ah rectangular batteries, 86 cells in each. These 75 ah cells are larger than the 30 ah cells used in the Zombie, and so they are thicker at ~ 1/2", thus 86 of them stacked in a row takes up ~43", so call the box 43.5" long. There is not a single area in the Insight, other than doing a ticky-tacky just fill the hatch area thing, where a rectangular box 11" wide, 12" tall, and 43.5" long can fit.
The other issue is weight balance, a priority so the car will handle very well, even though it will be about 1000 lbs. heavier than stock! Properly balanced and with new suspension pieces and light but strong bracing, the car will drive well. Improperly balanced, it would be a nightmare!
With the above considerations then, I've decided on 11 modules, 10 of them identical with an 11th one holding fewer cells and thus being a little smaller and lighter. Each module will be a flat-shaped rectangle that can be mounted either vertically or horizontally. The modules will be ~ 5" thick x ~12" tall x ~ 32" long, and will contain a 3P8S cell arrangement.
Doing it this way drops the BMS board count to 1/3 the number required for three separate 318V BIG batteries. Visualize 8 cells stacked on top of each other with two identical stack on each side. Each stack is in series to get 29.6V @ 75 ah, and going from left to right, each cell layer is paralleled, for 3 cells in parallel. A central-mounted RegDeck board & BMS will be connected to all three stacks. Each of these 24 cell flat modules will be 29.6V @ 225 ah, with the 11th module being an 18 cell 22.2V @ 225 ah. Total pack is 318V.2V @ 225 ah for 71.6 kWh.
With modules shaped like this, I can squeeze 3 under the hood (one laying flat, two standing vertically) without blocking the view of the rare EV1 AC motor with the gorgeous Rinehart Motion Systems inverter mounted with it - in addition to performance, presentation is very important. The other 8 will go midship both in the now empty IMA chamber below the hatch deck area, and underneath it where the gas tank was - all of it a very tight fit, all of it not yet all worked out and finalized.
If it does work out, the competition grade sound system will go right back where it was, though it will now tilt up and away for battery module access and presentation.
I invite everyone to visit the 'Wayland's Words' section of my website to follow this project - the current posting has photos to go along with the story.
See Ya...John Wayland
Originally Posted by coulombKid
If you look at the parts of the current White Zombie cells the Dow cells are more like envelopes and can be stuffed into a lot of spaces prizmatics cannot. They would also lend themselves well to an under the car belly pan pack like is going under the new Tesla-S. Spread em out too much and connections weight will go up though. Weird side thought. My car needs a belly pan to clean up the aerodynamics. What if I raised it up a little and......