Installing the rear battery box

In February the youngsters register of the Volvo Classic Club dropped by to hear more about my project. Not only did I do a test drive of the presentation with my kids, I also cleaned up the garage so everybody could sit down.

Presentatie Jongerenregister VKV voorbereiden

It was a nice meeting by the way with interesting conversations and a nice pizza from our wood fired oven afterwards. A nice spin off was that suddenly there was enough room in the garage to turn the car around.

Installatie achterbak achter beginnen IMG 5644

So I took the frame fabricated last summer.

Frame installatie achterbak IMG 5645

I had to remove a bit more of the old spare wheel area but after that it fitted perfectly. Aligned the height according to my design and test fitted a Tesla battery module.

Tesla module passen IMG 5692

Worked out very well so I attached the frame to the chassis beams of the car.

Frame gemonteerd IMG 5715

I welded tubes in the beam to prevent it from being squeezed while tightening the bolts.


It exactly fits near the top up to the millimeter!

boven past op de mm

As per the design.

pst boven conform tekening

Next I installed the outer box and mounted the tow bar. That also exactly fits.

trekhaak past ook precies

And as per the design as well having the exact amount of spacing between the tow bar and the battery box.

trekhaak past conform tekening

The spare wheel area was a bit tapered do I installed new corners (old ones were rusty anyway) to match the width of the outer battery box.

zijkanten batterijenbak

The front edge of the spare wheel area was curved to accommodate the fuel tank.

nieuwe voorrand

Now it is straight and exactly aligns with the outer battery box.

nieuwe voorrand erin

I did not attached the flanges to mount the outer battery box in the design of the box. The cassis beam was not fully flat due to the new bumper mount supports. I had just designed the flanges and had them lasercut and bend.

tekening ophangstrip zijkant

Now I could install these at the correct height underneath the car.

ophangstrip zijkant

So I drilled holes into the flange and added rivet nuts in the chassis beam.

zijkant afdichtstrips

I did the same for the front flange. Furthermore I welded in bolts to install the tow bar easily with the battery box in place.

voorkant afdichtstrips

Cable glands

I did not think of every detail while finalising the design so I had to add some holes both in the mounting flange and the box itself.

strips ponsen

At the right hand side I had forgotten to add the outgoing gland for the high voltage cable and 220V input for the right hand charger.

uitgang charger cable

I did design the incoming hole and the charger cable and 220V AC cable did indeed exactly fit into the orange corrugated tube and in the gland.

charger en 220v kabel

After stitch welding all mounts I could take off the outer battery box.

ophangranden gehecht

And TIG welded the whole thing. Despite the fact that it is stainless steel I did do an attempt myself.

TIG lassen RVS randen

Wasn’t very easy and despite the low current it warped quite a lot. So I clamped a steel beam onto it to hold it in place.

Zijrand ingeklemd

While welding the front mount I also used a beam to fasten the whole thing and prevent warping.

voorrand ingeklemd

That did work out fine for the mounting flange itself. However the edge sticking down warped quite a lot 🙁

losse rand getrokken

So I could no longer install the outer box. That edge need to slide in between the new spare wheel area edge and the frame.

past niet meer ertussen

After some advice from Mischa I took my friend Eckold the shrinker and shrinked the warped edge.

Eckold krimper

It improved a lot.

Rand een stuk rechter

The outer box fits again and is ready to be bolted on.

achterbak eronder

Only need to do some minor tweaks to get it fully sealed.

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OldVolvo is a classic Volvo hobby blog by Lars Rengersen.

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