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Discussion Starter · #1 ·
So I am in the final stages of making a 108s LifePo4 conversion of my Ford Escape hybrid battery.
My initial idea for this pack design is to make it easily assembled and made, using the headway 38120 HP's as major structural members connected to laser cut/CNC'd plastic boards.
Here's a Look at inside the bay, for easy design parameters we have a square space
670mm Wide
465mm Long
120mm Tall
Do note the Main +/- contacts/contactors are to the top left, and safety disconnect/main pack fuse to the bottom right


Now, since i am using an off the shelf 108s Orion 2 BMS, the pack needs it's safety disconnects/fuses split into 1/3rd's instead of the almost half split of the OEM.
Please excuse the microsoft paint quality of this professional diagram. The first two are dimensionally accurate, and the third grossly not.

With the M6 terminal the 38120's are actually 38 x 135's
Now, the battery would be a 16 wide, 3 deep, and 3 interlaced high pack, with an example of the busbars needed on the first figure. In that example, the orange spots are places wire would run through the battery for both disconnects to function, the left side would go to the oem disconnect while the right may go to an additional disconnect.

The cells would be tied together in 3 long configuration by an m6 thread, and busbars would only be needed at the front and back of the pack. I would love if some sort of PCB can be also wedged with the plastic sheets to support balancing/voltage sensing leads, but standard ring terminals would be fine.
The spacing in the middle is for cooling, as the two OEM fans would be blowing directly through it..

Everything else has mostly been completely finalized, CAN-BUS control done to at least be usable.
While some thermal control is lacking, A can bus logger is in the mail wich would solve my issues
Here's a spreadsheet of literally everything needed to get this running!

Please do respond here or email me at (myusername)@gmail.com, and my budget is quite up there, since a replacement oem nickel pack can cost $4k!
 

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I would recommend going to the official FreeCAD community discussion board and soliciting there.

A special note on the laser cutting... Most engineering plastics can't be laser cut due to decomposition with toxic byproducts. HDPE is probably one of the more suitable materials for this type of project, and it is also a poor choice for laser cutting.
 

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That's a very cool service. Is there something similar for water jet cutting you might know about?

Sent from my SM-T380 using Tapatalk
 

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Waterjet, laser, plasma, and rotary cutters (CNC) are all methods used to cut sheets of material. SendCutSend uses laser on thinner sheets and rotary CNC on thicker sheets, with the thickness range depending on the material (they do various composites and metals). The cut finish depends on the method and the material, but I think that it's reasonable to assume that whatever a service such as SendCutSend offers is suitable for the material and thickness chosen.
 
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