Batterybox for 14S 120P (Austrian style)

dakoal

Member
Joined
Nov 8, 2016
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34
Good morning.

As Peter asks, and I also think it's a brilliant idea, I will post here the process of the Metalbox I build for my brother in law's powerwall.
It's an 14S 120P system with the "Bernhard Strunz" style busbar system.

I will start with 14S 80P because thesepacks are already built.
With the packs at the end of the year build the 120PSysem will be around 13kWh of energy, with+/- 10kWh useable.

First thing, what housing to use when you bring your powerwall build to someone else?
They always have concerns like "it will burn" / "my house will explode" .....

So you have to box it into a metal cave. Custom build is to expensive, so use something from the "homedepot" / "Bauhaus" / "Hornbach".

I found a perfect fitting shelf in a "Hornbach" store:
https://www.hornbach.at/shop/Haenge...200-mm-4-Boeden-3-Tueren/3205592/artikel.html

As I need 115cm witdth / 45cm height and 12cm depth it fits perfect.


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It has three doors and 2 seperators in the middle where we cut out a big window with only 1cm left around, so the packs can go through.


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The build was easy, but I changed some things. So I rotated the backside inside out, so I have a clean one depth inside, not the edges between the 3 backplanes.
An isolater (a old packing from Servers)
As fixing the packs to the backplane I tried different options. This was the best for me:

http://www.ebay.de/itm/Rohrclips-Cl...hash=item2efaac69be:m:mHsnG1TpVjnhPAJZ1B-gokg


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As you see, upside-down test with 80P no problem, maybe with 120P I will double the amount of clips.
The BMS ( www.energusps.com ) and 4 Fuse/Breakers are also installed.


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With 3 doors:


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It looks really good. And the exploding and burning thing is an issue at my house too....the wife...

Only thing is, will that metal case really help or is it just for peace of mind... I think it's the second one.

I've looked into metal cupboards for ammo and gun storage. They seem more sturdy, but also alot more pricey (in Europe... maybe easy to find second hand in the US).

Old second hand safes are easy to find too, but impossible to make holes how and where we want. Not to mention the weight...

I'll keep following your build.
 
When you watch the video from Daniel you will see the cells burning, one after one, not all together will fire up at once and fly around.
So for me its more a "prevent burning 18650's flying around".

 
What kind of screws do you use to attach those plastic brackets to the backplane? Are those regular screws or nuts with bolts?

[edit] aw duh, there's a wooden backplane!
 
For isolation the boxes are coated with 0,5mm plastic foil.

Additional the contacts are covered with a plastic cap.

I will do some detail pictures later on.

Here is an update: 20kWh useable are now installed (24kWh on storage)


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fHere is a detail pic of the foil.
Its a very robust one from a pond.

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The connectors a covered with this blue plastic thingies from 10Gb Ethernet SFPs

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Here you can see the difference from 10 to 20kWh Powerwall, expanded on 1st June.

The voltage drop in the night changes from:
4.07 - 3.72to4.08 - 3.88 Volts per cell pack or from
57 - 52 to 57 - 55 Volts for the whole system


image_zaborr.jpg
.
 
Really like the cabinet idea, I'm planning something similar.
What fuses/fuse holder have you used?
 
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