Electrical System

The electrical system is split into two main parts:

  1. The high-voltage system for moving the vehicle.
  2. The 12V dc system for lighting, entertainment and accessories.

The 'high voltage' system is derived from the battery and this could be anything from about 100V to 800V. There are a few manufacturers working with 800V systems though (Hyundai and Kia) due to the safety issues. The main reason for using higher voltages is the ability to use more powerful motors.

Note: Rob designed the electrical system for his Fisher Fury R1 and built a custom wiring loom for it too, so we have no concerns over the design of the electrical system for the OSSEV®. The main areas of learning are around the high voltage system and the CAN Bus.

Why Have A 12V Battery?

We are using a 12V battery in our MX-5e and the OSSEV 1 because it is needed for the following items even when the EV is switched off:

It is possible to have a dc-dc converter connected to the main battery all the time but, this is not very energy efficient and you often want to disconnect the high-voltage circuits for safety reasons. Having a 12V battery makes it much easier to test things in the MX-5e as we build it, without the main battery being required at all.

Further Reading