My DIY Tesla miniwall :)

Z

Zagy

Member
Joined
Apr 5, 2017
Messages
36
Hello all,

I have been working on my miniwall for a long time now and this is the result:

https://scontent.fsof2-1.fna.fbcdn....=dfb28b4709db3e273e547326e7934b2b&oe=5A3D1C70

The packs are on average 29,4A each (tolerances are: the highest is 29,6Ah, the lowest is 29,4Ah), the busbars are 6mm2 solid copper wire, the cells are fused on both sides with 0.3mm2 copper fuse wires. I have cells for 7 more packs that will average about 10Ah each but I have not built them yet - the idea is to add them to these so I can bring up the powerwall to 24V 40Ah.

The wall will be 24V 30Ah (for the moment), I have a Steca Solsum 6A PWM solar controller and a 24V UPS for 220V. Still do not have the solar panels, but I hope this changes soon enough. The plan is to buy 2 x 100W panels and run them in series and charge the powerwall.

The wall will be used to power the lights in my home, I will get a 220V outlet for powering small appliances.

That's it for now, will keep you posted :)

Additionally - I have made a small powerbank for camping/hiking:

https://scontent.fsof2-1.fna.fbcdn....=7c96289b99d9f5be324fc35f402d7d9b&oe=5A5E8F53
 
Welcome! Good start.

Comment: Are the 0.3mm fuse wire thin enough? have you tested the current needed for them to blow?
 
I haven't tested them but as per what I've read online these will melt at about 5-6 amps, which I think is safe enough.

EDIT: just measured them - they are 0,42mm2, and should be good for about 7 amps.
 
Are you sure about the unit?
0.4mm2 is 0.7mm thick... Im using 0.2mm and that melts at 7A.
 
I guess my calculation is not very correct :D - the wire is 0.3mm in diameter and probably will fuse at about 10A.

That was the thinnest wire I could get - hopefully it will work, and I do not plan to use loads greater than 300-400W.
 
I use 34WAG which is .2mm ish and blocks at 7-8A @ 3.5V ot 5A @ 4.2V from my testing
 
0.3mm is 0.07mm
This will fuse in 10 seconds at ~13A , and in 1 second at ~22A

If there are any electronics stores near you, try looking for general hook-up wire (similar to the picture)
This often has many fine strands of tinned copper wire.

The pictured wire for example has 13 strands of 0.12mm (about 36AWG), so 1M of that wire would net ~13M of fuse... not bad for less than a dollar :D


image_jguolk.jpg
 
Mostly fuses are used in case of dead short or cell goes bad - in that case, join piece of your 'fuse' wire to each end of a cell (safely or at the very at least on camera) if she burns up it's a winner ( please be careful lol )
 
I would even go so far as to test with a low voltage cell as well. Test it on a 3V and a 4V cell and see how long the wire takes to blow. If in both cases only takes milliseconds, your golden. If it takes several seconds in either case, go smaller on the wire.
 
I will try it these days with a few low-capacity cells in parallel and see what happens :)
 
Don't hold it like this with fuse wire.... speaking from experience (I was just a little kid)
Yeeeowwie!


image_pgncgv.jpg
 
mmmmm, 18650-cabobs ;)


Nice layout
 
Hi, haven't posted in a while, but this is the TinyWall projectso far :) The panel is a 30W24V one.


image_bowjsk.jpg


Currently the wires are thin (0.5mm2), but I am just testing the controller and BMS. Once they meet the initial inspection and complete the tests I will get thick wires and complete everything as it should be.
 
You must log in or register to reply here.
Back
Top