Finally i made enough of the BMS boards that i can comfortably go and take apart those Jaguar modules.
I cut them down to 2P blocks for 120Ah.
First i remove the plastic cover and BMS connection. Then i mark cuts that will make the 2P blocks. Some of them can be used 2P2S since they were meant to connect to the other side of the module.
I then separated individual cells and drilled 5mm holes in their tabs. I connected cells in groups of 2P8S with a tab for + and – side.
Today I have made enough cells to fit into the front box. Hurrah! And when i calculated their number i got 10 groupd of 8 cells which i will use in modules of 16 cells as BMS supports that. And behold, all 80 cells will fit the front box! I guess rear box will holt only 2P16S + 2P8S which is 86Vdc
I made more of the BMS cables for my Minifit connectors. I think they are great. Very compact and firm attachment to the board.
I crimped terminals and inserted the wires by their numbers so that there would be no doubt on how to assemble them on the battery side.
After some more work on the battery packs i was looking at how to assemble and connect them in my pack. Orientation of the packs is vital to ease of assembly. I learned with Mazda that i need to put modules together so that assembly/disassembly is safe even using metal tools.
I was sitting in front of the battery thinking how to do that in constrained space of the battery box, when it dawned on me! Battery terminals are oriented to bolt cables from the top. If i would make them accept copper rails from the sides, i could make the connections more managable… straight rails. Also since i will be stacking two modules one over the other i need to pay attention to clearance between two modules. But terminal is just under the top/bottom of the modules leaving no space for the head of the connecting bolt. Just using the bolt on existing terminals would create possibility bolt heat would touch something conductive on the other pack and … BANG!
But end terminals are welded to battery tabs. And any twisting could tear them off and destroy that module! And taking 2P8S modules apart is out of the question since i already taped the modules up and made all packages nice and tight.
Question is now how to bend 1mm thick end terminal by 90deg in a specific spot? Answer lies in a correct use of torque and support. To achieve that i made a bending tool. It is made from 4mm copper contact, steel could do, but it is more difficult to form.
I bend it at right angle and cut one end to size, so it will support the force of my torque directly on the spot where contact needs to bend. The other side i bent up and taped it up so it wouldnt hurt my hand.
I also drilled a hole for the M6 bolt and after some thought i decided to solder a nut underneath it. This allows me to assemble the whole thing without having to look everywhere when that nut rolls away :).
With this tool bolted to the terminal i pushed into the terminal to keep it in position and pushed down on one end. Terminal twisted exactly on the spot i desired and the form of the tool allowed me to remove it sideways from the bend. Voila!
I now have all my end terminals bent so they accept rails from the side.
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