Construction

Construction

Early Construction Designs

A design for a 120 kWh chassis

Concept Art



Total pack capacity is 100 x 1.2kWh = 120kWh.
This is a truly huge capacity, twice the Tesla Model 3 and five times the Nissan Leaf.

To compare with realistic ranges at motorway speed:
a Nissan Leaf is 24kWh (80 mile range) to 30kWh (100 mile range),
Tesla Model 3 is 50 kWh (250-350 miles range).

Hypermiling could easily make this cars range 1,000 miles.

So this would give a practical range of 300-400 miles at motorway speeds (70-80mph).
Due to the low cost of lead acid batteries this would mean Tesla ranges for Nissan Leaf money.

The lead acid battery for this vehicle will be a deep cycle 6v unit currently in use for neighbourhood vehicles and electric golf karts.

These batteries have a useful life of 350-400 charge cycles.
This is for a complete discharge and charge cycle.

For this vehicle that would be a journey of 400 miles on one charge at motorway speeds
and would mean the vehicle would have a life of 140,000 to 160,000 miles before the battery would need replacement.

This is a completely unrealistic scenario as no average person would be driving at 80 for 5 hours every day for about a year.
A more realistic scenario is a combination of high speeds, low speeds and stopping, which would give the range as approx 1,000 miles per charge.

This would mean the battery life would be around 350,000 - 400,000 miles, beyond the life of the car.
So essentially this means the battery would never need replacing.

Updated car design


Original Blender Model
This uses 100 x 12v/100Ah AGM batteries as they cost less than 100 x 6v/200Ah AGMs.
Most likely due to popularity.

Also included in this construction is a Tesla Model S 400kW power unit which has been sourced from breakers in the US.

Construction is Underway

Battery Box


Rear Subframe


Front Chassis


Battery



You will also notice that the chassis is on the ground unsupported.
This is a major step as this is now a rolling chassis that supports the full pack of batteries

Here is the weight of one battery: 30kg

There are 99 of them in this version, add the weight of the supporting chassis and this works out at approx 3.5 tons

If Brunel made an electric car this would be it!

Updated Suspension

The Transit suspension is just not good for this purpose, so a new design is being pursued using twinned coilovers and double wishbone:


This supports the weight much better.
It's is much more compact but still rugged and strong.

Body



Imagery edited in gimp, CAD created in blender, Video editing in Avidemux