More Battery Pack Musings - Kraln's RX-8 Blog

What has 5,000 welds and 600 tiny fuses? One battery module. I drew up a schematic for the module to get an understanding of layout, and it looks like it will be the easiest to do 10 x 60 with a somewhat offset pattern, to accomodate the heat exchanger. (see above)

This has the downside that nickel strips simply don't carry enough current; using 8mm x 0.3mm nickel strips in this way, the pack would only be able to supply about 150A before overheating. Thankfully, there are some options here, I found a supplier that makes hybrid nickel (weldable) copper (high current) solutions, and they should be able to make something perfect.

combo of copper and nickel

Apart from that, I thought it might be good to have an aluminum frame for the module that the PETG panels are attached to. And I can use laser-cut PETG panels as cell holders, also.

70mm2 copper wire as collectors for the high voltage and bob's your uncle.

Author: kraln

Jeff Katz is an engineer and serial entrepreneur who has founded companies across a wide variety of industries including security, finance, and IT. He's worked everything from electrical engineering through firmware, cloud architecture, engineering management and CTO, for startups as well as multinationals such as Telefónica and Daimler.

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I bought an RX-8 with the intention of converting it to run on Hydrogen. Conveniently, the hydrogen fueling network where I live was shutdown shorly after I brought the car home. After driving the car around with the original drivetrain for much longer than I originally intended, it started to lose significant power. Rather than simply replacing the existing (fun, but unreliable) drivetrain with a rebuild, or a different (boring, but more reliable) gasoline engine, I'd want to return to the original goal of making my RX-8 zero-emissions.

The goal is an RX-8 that, from the outside and inside, is indistinguishable from stock. All safety and comfort features should still work, and the car shouldn't gain too much additional weight. The original structure should stay as intact as possible, and the handling and dynamics should be as close to as-delivered. It should still be fun to drive but reliable as a daily, and it should still zoom-zoom.