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In the meantime I'm playing with electric parking brakes from the BMW X5/X6 :D
So BMW uses an electric motor to pull mechanical cables to actuate mechanical parking brakes, combining all of the complication of both mechanical and electric actuation systems, with no benefit other than to replace a lever in the console with a switch? This is why I have no desire to own a BMW! ;)
 

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Discussion Starter · #166 ·
First stage of the main battery box fabrication is nearing completion. This steel structure will be welded into place between the main chassis rails providing additional stiffness to the VW chassis and a sealed enclosure for eight Tesla modules :cool:
 

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Very good concept. Does that box weigh much more than the metal it is replacing? How much weight do you expect the bare chassis to increase by and then add with components over the ice setup?
 

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First stage of the main battery box fabrication is nearing completion. This steel structure will be welded into place between the main chassis rails providing additional stiffness to the VW chassis and a sealed enclosure for eight Tesla modules :cool:
Does that box weigh much more than the metal it is replacing?
In the current design, is this box replacing any metal at all, or is it added under the floor?

Here's Kevin's earlier description:
3D mockup of proposed Tesla module layout for the two battery boxes. One box (8 modules) will be mounted under the floor between the chassis rails, and another (6 modules) above the motor where the petrol tank was located :cool:
(follow the link back to this post where there is a drawing)
 

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How much weight do you expect the bare chassis to increase by and then add with components over the ice setup?
Kevin's earlier report in this thread:
I spent some time reviewing the weight of the Bus conversion today;

The original bus weighed 1036kg (2285lbs).

Removing the ICE, Gearbox, Fuel Tank, and replacing the front/rear suspension with Red 9 resulted in the bus weighing 852kg (1878lbs).

Installing the Tesla Drive Unit, 4 Tesla Battery Modules and rear battery rack resulted in the bus weighing 1046kg (2306lbs).

Now for another 8 Tesla Battery Modules (200kg / 440lbs), 2 Battery Boxes (TBD), and a bunch of electronics (TBD).

While heavy, it looks as if my 1500kg (3300lbs) kerb weight target is achievable (same as a Nissan Leaf), while leaving 570kg (1250lbs) for payload :)
So the net increase is 210 kg and counting, and likely about four hundred kilograms by completion.
 

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Thanks for your updates Kevin! That looks like a very solid box. What is the thickness of the sheetmetal used?
And how do you mount / hang the modules in it?
Do you mean 8 in such a box or is this box for one module? (difficult to estimate the size on the photo)
 

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Discussion Starter · #171 · (Edited)
Hopefully these photos will help :)

The basic idea is that we're creating a steel lined cavity between the main chassis rails that is large enough to encase 8 Tesla modules.

The Tesla modules are not attached to the cavity lining directly, rather they are mounted on a 5mm thick steel plate that becomes the floor of the cavity. The cavity floor is bolted to the base of the cavity lining structure using ~30 stainless fixings. To ensure the cavity remains airtight we will use a flexible sealant between the cavity floor and cavity lining structure, similar to the technique used on the Nissan Leaf battery.

To accommodate the weight of the battery we have extensively reinforced the chassis rails and the van floor.

At both ends of the cavity we will fit Tesla 'exhaust' valves and sheet steel to duct away exhaust gases from the main cabin in the event of a battery fire.

Hopefully we'll have the metal work installed early next week and I'll record a video at that time. I'll also weigh the bus again to see what the impact of this steel has been :cool:
 

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Discussion Starter · #172 · (Edited)
Good progress on the panel that will become the 'floor' of the main battery box. This structure will be inverted and the box section welded to the reinforced main chassis members providing a sealed cavity for eight battery modules. Every bolt has a corresponding nut that is welded to the box section and final airtightness will be provided by sealant similar to that used on the Nissan/Tesla batteries :cool:
 

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reusing the Tesla Model S/X pressure release valves... two sets at each end of the main battery box :cool:
I notice in the video they refer to these vents as "Fire Vents".
Does anyone know roughly what pressure they operate at ?
I wonder if they also vent (both ways) to compensate for temperature changes inside the battery casing ?
 

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There is an another vent on top of the battery wit a sort of filter in it, I presume that's the one for equalizing pressure.

The rubber vents are a sort of check-valves, only air out.
Do you have photos of this? I havent seen another valve before.
 
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