What I would do differently..

hbpowerwall

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I just want to jot some notes here as I think of things I could do better with myPowerwall

1. How I set up the sheds, yes with the wood backing - hindsightand a bunch of interwebbers said it's a dick move. Wellnow, but not back then I agree. My theory was it's still in a tin shed and it was a cheap way to give strength to the shed walls so up it went.

2. Size of thebattery shed - IT NEEDS TO BE BIGGER, it would make it easier to work on, check& maintain.I could also geta lotmore cells in there.

3. Fuses - I used 0.23mm winding wire that was plastic coated - it was a bitch to get the coating off and contributed to soldering iron tips dying far too fast. Moving forward I'll be using thiswill be much easier to handle and will faster to 'install'

4. Fuses 2.0 - After seeingTHIS this happen to Rohan all new packs will be double fused. His issue was design that has subsequently been fixed but had it been double fused this would have been a much small issue of a fuse blowing!

5. Busbars - I've put considerable effort into my 'Busbar' process includingthe old Busbar Saga. With the growth of the powerwalls out there many different ways have emerged so of them listed hereone that stands out isflyjabiru11's busbars ( link direct to the good stuff
). They are super easy to make & easy to find cheaply or free ! I recommend you check them out if your planning a powerwall build.

If you feel I could do something better that isn't listed above please feel free to leave a comment.
 
I'm curious on the wood shed as I was looking in to purchasing a metal structure and reinforcing with wood as well. Obviously wood burns but is that really an issue? If your batteries catch fire, isn't it going to burn anyway? I haven't seen many non-wood sheds here that have enough structural strength to hold up the battery pack mounts.

I suppose you could put the plywood on the outside behind the shed so the packs are against the metal, yet the wood is still reinforcing it?

Just curious before I invest in a proper storage shed in a couple of months.
 
Perhaps paint the wood with fire retardant material - guess every little bit counts.
 
I covered my wood backer in sheet metal. Also nice that it connects everything together with a shared ground. The small form factor pc mounted to it is even able to dissipate some of it's heat to the backer panel.
 
If the quantity of cells we are mostly using catch fire there's very little the FS would be doing, other than contain it and watch it burn out - if you are daft enough to have your packs in a habited space enclosing it in cement board (hardy board) or a few layers of fire retardant plasterboard should contain it long enough for the occupants to escape - combined with interlinked smoke and heat alarms.

Heavy section RSJs in a portal framed building will be structurally damaged in a fire involving our packs, so what your load carrying material is should be the last of your considerations .........
 
If you don't have a building up yet, you might consider brick walls. You could then use hbpowerwall's pack holders with no issues.
 
I plan on using concrete board when I build my shed. They use it to lay under tile here in the States. I really think the smoke if more dangerous than the fire though.
 
Wood burns? Damn, no one told me ... what about the tyres ive got my third module resting on?
... I know, my setup is designed to let everyone know when its on fire, liberal black smoke!

Mike from NZ has painted his cabinet with some kind of fire retardant glassy stuff ...

Interested to hear his thoughts
 
mike said:
I wonder if something like this welding blanket would work. You can still reinforce with wood on the inside then cover the wall where the packs are mounted with a welding blanket. You can screw through for the mounts. It sucks that it won't look as neat/clean though.
https://www.amazon.com/dp/B0057RJD0E/

That has beenbrought upa few times, like the idea - but would be hard to make it look good ( I know function over form ..lol )
3nergE said:
Mike from NZ has painted his cabinet with some kind of fire retardant glassy stuff ...

Know I've seen I some where before !!!
 
I went for a concrete steel reinforced structure with fireboard internals, which is non combustible and perfect for this type of install. It looks like chipboard, but has a self extinguishing material mixed into it.
In the UK, it is a standard requirement for all electrical supplies, so I could source it easily.
 
Just a good quality marine plywood should have a retardant spec. Expensive sure, but it's what they use in most every telco room of every skyscraper in the US anyway.

But the biggest thing I'd do differently if I was you is fewer videos while you are eating!!!!! LOL JK

Keep up the inspiration boss!
 
what i would think about

in the worst of all worst possible circumstances, your hole shed sits on fire, the cells may be exploding any second, the last thing i want to happen is:

the door flying right at me while i try to check out what is happening

given the shed is somewhat resilient to external and internal force-application, i would consider some sort of planned pressure release, like it is done with rockets

a quick pic to illustrate what i am talking about http://imagecrow.com/albums/spacex-releases-photos-of-its-rocket-launch-and-first-ever-sea-.jpg
to the left side

this of course means, the door should be atleast as sturdy as the rest of the shed
 
it is correct for my use, always best to check for yourself and everyone's needs are different.
 
hbpowerwall said:
4. Fuses 2.0 - After seeingTHIS this happen to Rohan all new packs will be double fused. His issue was design that has subsequently been fixed but had it been double fused this would have been a much small issue of a fuse blowing!

What do you mean by double fused?
 
I supose he means fuse on both sides positive and negative. Rohan's problem was that the positive bus made contact direcly with the cell so current hasn't passed by the positive fuse that remained intact, with a fuse on negative side this would not have happened.

But this is an an issue of particular desing used, multiple cables used as bus bars and tied in a side with another piece of cooper cable that have been pressed against the cell and broke the plastic.

Regards
 
so many comments which I couldn't go through them all but here's my 5 cents worth (AU doesn't have 2 cents any more ;) )

These are just my thoughts on overall installations I've seen everywhere, not just HBpowerwall.

1. wood backing
wood back is fine if you use really dense wood, fire will only make it singe and not burn up so much. if it burns it'll just smoulder. You'd have to find a person who knows which wood is best though as I'd have no idea which.
wood is better than just tin wall as you have some sort of insulation from metal for any accidents of dropping any cable against the tin wall in case there's some negative or earthing you're not away was there.

2. bigger shed.
it should be optimized more, you have them across the whole wall rather than condensing it,making one of those swing our arms so they can be side by side (safely of course to not knock each other). Then you can open them up like a book to get to whichever cell you want. you can then also put them into a corner out of the way.

3. fuses
to me, fuses should be rated at max charge and drain from the solar/inverter, not max the battery can do. if a whole cell is expected to get max charge and drain at 2 amps then every battery should have the shared current of 2amp plus a little more to prevent sudden pops or surges. So if s single battery ever sees .5 amp ever, why the hell put 5 amp fuses... that's my argument overall.

4. fuses 2.0
each battery should be fuses both ends. every cell should have a large 100AMP protection fuse in case of shorts anywhere along the main power lines, and that's every cells. Just like it's done in car audio with 2000W+ systems with super capacitors etc..

5. bus bars
As per 4. the bus bar at the ends should be fused as well as insulated, seeing so many people having bare wires and it scares the living days lights when I see it on youtube so often. Even put covers over every cell with fans below blowing through to the top for venilation but at least they are electrically isolated from any accidents.

that's just my thoughts.
 
tremors: First, I'm going to assume when you say "every cell" you actually mean "every pack" (as you mention at one point 'ever cell should have a large 100Amp fuse')
Second, fuses aren't all about popping when going over a certain amp rating. They are also rated at a certain amount of power loss due to size. The reason why most go with a ~5amp fuse is because if you go smaller, you are starting to get power loss (which is in the form of heat, which weakens the fuse, which could cause it to blow unnecessarily)
Third, depending on "where" the fuse is located at (cell, pack, bank, main power leads, charger) depends on the size of the fuse. When at the charger, yes, they are rated for the charger. When at the Main power leads, it's rated on what the max discharge would be safely. At the bank, the max the bank should ever put out (which is not necessarily the same as the Main power leads). At the pack level, what the pack would give out. And at the cell what the cell can handle. The reason for the cell level fuse is to keep the other cells from shorting 'through' that cell if it goes dead short.

I agree with #1 and #2
 
With this fire thing we are totally in the realms of fantasy ...

No one has yet demonstrated it's possible to start a fire with a 18650 in normal operation

You may remember I offered a $1,000 prize to anyone who could start a fire using UNFUSED 18650's in a powerwall and make a video of this.

Most people here fuse every cell and are still scared of fire !!! Ridiculous ...

Same with "double fusing" ....irrational ...illogical ...ask any electrical engineer
 
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