This is gonna be an ongoing build log for a DIY ev project that I plan on working on over the next couple years if my skills with esk8 are any indicator.
Enjoy this deliberately grainy image, I’ll upload more once I knock off work
So the plan is to pull the old ICE engine out, then figure out what sorta condition the transmission is in before making my next move. I’ve been in contact with a couple of factories on Alibaba for motors but I’ve been leaning towards the Kostov K11 because it’s got really good specs for the local price $2200AUD. this motor has the torque for direct drive but I don’t think I’ll be able to get up to highway speeds without gear reduction as most DC motors top out at 5000rpm. I have also considered using a one speed gear reduction but don’t wanna have to have one engineered as this project is already gonna cost me an arm and a leg.
There should be regular updates to this post, and I do plan on live streaming portions of the teardown and build process if anyone is interested. If anyone has questions ask the fuck away
For batteries I hope to use the Headway 38120 as I feel they are the best middle ground between size and power. This car isn’t designed to be an everyday commuter, but instead a far higher performance vehicle than was originally intended. 10Ah @ 100A is a pretty beefy cell, and you can get higher amperage models such as the 38120HP which is 8Ah @ 200A. If anyone has any comments regarding batteries I’d love to hear it
Another reason I chose Headway cells is because they connect together simply using M6 screws and busbars which means building a pack is super simple, and adding more cells or modifying a layout can be done in minutes. I haven’t settled on an exact pack voltage yet so having this flexibility is key for me
There’s been a couple dozen people that have homologated (love that word btw) EV conversions so I know it’s possible. I need to link up with one of the guys that does the certification process so I can figure out whether things like motor mounts and such need to he professionally engineered or whether I can use my buddy. If the process is too hard I will use this purely as a track car
Been peeping Battery Hookup for months, it’s such a good price. My only thing with those cells is that if I wanna make the pack bigger (Ah) then I’m adding a heap more amps that I won’t be using therefore wasting them. I am aiming for around 1000A peak and this can be achieved with only 5 of those cells in parallel. A lot of specific decisions like that are up in the air currently
I’ve considered getting some for my board as they would just fit in my enclosure and can pretty much provide same power and range as my 12s5p 30Q. I’m gonna order a couple of cells so I can get them in hand and visualise how they will fit and stuff. LiFePo is promising for EVs because the chance of things like thermal runaway is essentially zero and they last for thousands more cycles
LiFePo is also slightly lower voltage, 3.2v Nom instead of 3.6 nom which means that a 13S pack is possible on current 60V vesc without getting too close to max
I myself am looking to strap 14 of those Headway 38120HP’s to my deck this winter. I’m excited to see anyone consider using them for any purpose.
I look forward to finding discharge graphs at 150A, 175A, and 200A. That seems like a fair comparison to 30T’s, considering the weight difference (360g vs 68g). That said, those discharge tests aren’t performed at 0F and 30F, which is what interests me most. Do you have cold mornings in which you’ll need to start your car and drive up a hill?
I’ve wondered who was going to put together a 23s pack mated to trampas 75/300 VESC. 8.38kg and less than $240 per P group.
Sorry if I missed it, but what voltage are you planning on running?
Have you given any consideration to the Spim08hp pouches? Seems like more for the money. I was daydreaming of making a 96S10P pack for what I thought might be cheap, but I think used EV modules can be had for even less and then you don’t have to do all the connections/housings yourself.
