I wrote the following before receiving your latest above.

I believe we can only stack the cells 16 high in the 215 height because we need a 16 mm overhead for strapping and manifold. n x 12 + 16

I see from your other thread,

https://www.aeva.asn.au/forums/viewtopi ... 178#p70178
that the cells are 120 mm wide. I understand the tubes are 6 mm. Allow another 2 mm for the cooling plate wrap and the strapping. That's 8 mm each side, bringing the total to 136 mm. And perhaps the 154 or 153 mm dimension of the manifold can come down to 152 mm. That would make the formula

k x 136 + 16, giving the series 152, 288, 424, 560, 696, 832, 969, 1104. The other dimension is

m x 354 + 120, giving the series 474, 802, 1182.

So the best we can do in the 1092 x 253 space (under the boot) is 802 x 152 which is 2 x 1 x 16 = 32 cells. However this happens to be the only box in the car where it is possible to expand it (at the risk of having too much weight on the rear wheels) but only in the 253 dimension. If we expand that to 288, we can have 2 x 2 x 16 = 64 cells.

In the 678 x 500 space (under the bonnet) with a missing corner that brings those dimensions down to 586 and 376 in places, the best we can do is 560 x 474 which is 4 x 1 x 16 = 64 cells.

When you look at the MX-5's battery layout diagram, you may wonder why the two fuel tank boxes couldn't be combined into one box. The main reason is that you couldn't get them in or out if they were in one large box. To get the rear one out, you must first lift out the forward one and slide the rear one into its place.

So in the two 678 x 253 spaces (fuel tank), the best we can do is 474 x 152 which is 1 x 1 x 16 = 16 cells in each.

That's a total of 160 cells. 32 more required.

None of the remaining spaces can take any cells in the laid-flat orientation. If instead they are standing on edge, with the 153 dimension in the 215 height, then in the 632 x 130 space (radiator) we can fit 474 x 124 which is 1 x 9 x 1 = 9 cells.

In the 908 x 130 space (behind rollbar) which I really don't want to use, due to sun exposure, we can fit 802 x 124 which is 2 x 9 x 1 = 18 cells.

That's a total of 187 cells, and none of the remaining spaces can take any cells in any orientation.

I could probably live with the voltage of 187 NMC cells, but I'd still have cells exposed to sun, and I'd still have 6 separate battery boxes. I was hoping to get that down to 4 or less.