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Discussion Starter · #1 ·
Edit: Apologies for the formatting. I wrote this in markdown and decided to leave it as such because I can't get the bold/list/etc working in the posting field for the forum.

Hey everyone, I was hoping someone might review my planned build and give me some advice. I have quite a bit of expereince in both electrical and mechanical, including a master's in Electrical Enginering where I had once class where I designed an entire inverter and controller for a permanant magnet motor. In this class we had reviewed all the components that go into an EV, but It's been long enough since I've taken the class that I doubt myself and am not sure about some of the parts that I need.

I already have some of the parts, sepcifically:
Motor: **Siemens 1PV5138-4WS24-ZW12**
Inverter: **DMOC 645**

So I will need to design the system around this.

The goal is to have a killer rock crawler that can make the rubicon trail by next year.
kilowatt-hours isn't a big worry to me, as the Siemens motor that I'm using has a shaft that goes all the way through, and I believe I can hook up a small gas engine to this to charge the vehicle (can someone confirm this?).

A **1979 Jeep Cherokee 4x4** will be the donor for the conversion.
It's pretty much all stock at the moment. With a **T15 transmission**, a **Dana 20 transfer case**, and **Dana 44 front and rear axles**.

The goal is to hook the Siemens motor straight up to the transmission.

The sytem needs to run at around 360 volts (I get the best performance if I can max out the DMOC 645), so my biggest question here is how I need to setup the battery system.
I want at least 20kWh, at around 350 volts, and I want it to be able to provide 400 amps peak. This said, I've been looking at these [Samsung SDI ESS]( batteries from evwest, but I haven't seen much about them on the forums. This is nice because I would already have the BMS and cooling hardware built into the battery, and the rack mount is perfect for what we're planning with the vehicle.

However, I'm pretty lost on the connections after this. After I have 350 volts, does this just plug straight into the DMOC 645? Obviously I'll want some fuses at this point, but then what about charging? And what about regenerative breaking? Which I'll need if I plan to run the shaft from a gas engine for charging as well.

Thanks everyone for your help. Hopefully I can figure out the rest of the system and start ordering parts!

## New Jeep Hardware:

#### 4-link suspension
Front/Rear axle truss
Barnes 4 link kit front/rear
4 link dom
Misc tube and fab
King 2.0 coilovers front/rear

#### Gearing upgrades

Atlas II 5:1
Front and rear axle re-gear

#### Axle upgrades

Reid racing kunckles
Front limited slip
Rear locker
Front upgrade kit
Steering upgrade (full hydro)

#### Axle secondary upgrades

Front/rear shaft

#### Roll cage/body armor

A bunch of DOM tube and tabs

22 Posts
I don't know the specs of your motor and you don't mention axle ratios or tire size but I'm curious to hear your thoughts on gear reduction. I'm starting to plan a 4x4 build (not a crawler, just an around town rig). I'm finding that I might not a transmission because the motor produces peak torque at 0 rpm where an ICE doesn't do anything below 1000 rpm and needs several thousand more rpm to get to peak power.
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