Hi from Aotearoa 40-60kwh build 432P 14S MAYBE MOOOOORE

Joined
Oct 10, 2018
Messages
79
Hi guys,

I am from Pegasus a small town north of Christchurch New Zealand.

I have been watching and reading and learning about energy storage for about 3 years.

I have a 9KW solar panel setup 12kwh of lead carbon storage (which is great) and two electric cars (both Nissan Leaf) our family of 5 are petrol free! Such a good feeling.

I have started to crave more energy storage and stumbled on a rather large supply of free 18650 cells! Barely used and 3000Mh capacity.

I am going to aim for the sky and try to build 60kwh of storage. Its obviously not going to happen overnight and I may do a video blog to document the process.

Sheet metal fabrication is my background but no training in electrical so trusting a sparky mate of mine and the community to guide me.

I AM IN TOO DEEP NOW. no turning back.
 
"stumbled on a rather large supply of free 18650 cells"

Every NZer wants to know how, when, where & how can they lol

Welcome sounds like your home is carbon friendly !
 
Scottietheyoung said:
I am going to aim for the sky and try to build 60kwh of storage.

But, you've already got at least 60kWh of storage, is 9kW enough to keep that topped up ?
 
9kw should be enough - i run with 4kw on 40kwh of storage if it runs down takes a few weeks of good days to get back to top of charge tho
 
hbpowerwall said:
9kw should be enough - i run with 4kw on 40kwh of storage if it runs down takes a few weeks of good days to get back to top of charge tho

you need a bigger roof
 
Sean said:
hbpowerwall said:
9kw should be enough - i run with 4kw on 40kwh of storage if it runs down takes a few weeks of good days to get back to top of charge tho

you need a bigger roof

I need bigger north facing roof lol
 
hbpowerwall said:
"stumbled on a rather large supply of free 18650 cells"

Every NZer wants to know how, when, where & how can they lol

Welcome sounds like your home is carbon friendly !

I could barely believe my luck! although after watching some of your channel HB I dont know if I would call building a powerwall lucky!



In summer i get paid for power, autumn and spring is very cheap and winter is still expensive. I am running a 6 gpumining rig also which demands power.

Our hot water is evacuated tube in winter its a double edged sword with little solarthermal energy and too little photo voltaicenergy.

60KWH is the goal but anything over 40 would be pretty helpful.


Yea the house ispretty low E. Although Ireally want to work myself away fromANY dependence ongrid energy. I am even thinking about building a small turbine in my yard! hahaha.


Sean said:
Scottietheyoung said:
I am going to aim for the sky and try to build 60kwh of storage.

But, you've already got at least 60kWh of storage, is 9kW enough to keep that topped up ?

believe me, I am already talking with my solar panel supplier about upgrading 12 panels to higher outputs. the key is being able to charge a leaf overnight if possible. with 2 and work hours its frustrating to be burning power off all day only to have a car come home and struggle to charge it!
 
hbpowerwall said:
Sean said:
hbpowerwall said:
9kw should be enough - i run with 4kw on 40kwh of storage if it runs down takes a few weeks of good days to get back to top of charge tho

you need a bigger roof

I need bigger north facing roof lol

We have 1.5kW facing due west - can highly recommend it as it protects the batteries from load for 1-2 hrs of an afternoon after the sun has moved on from the north facing panels... only during summer ofc...
 
Our panels from google earth, the grass seed went down the week prior to this pic so hence the section full of dirt! hmmm cant seem to upload pics?


image_kbfzlc.jpg
 
after you put them in the "Picture section", you have to click on the images to add them where you want them in the post.
 
Sean said:
just buy two more leafs, a zappi, and use them on alternate days

Just looked at both of those things :)
 
I am making sloooooow progress but hey progress non the less... actually what has slowed me down is my ability to commit to the task. I have been all over the place about what cell holders to use, layout, P size and solder or spot weld.

well now I am all in! thanks to AJW22 I have the PERFECTcell holder which I am 3d printing by the kilo right now (no my wife isnot enjoying the noise it makes on the kitchen bench :D)

I will keepmy aimhigh andplan ona 432P 14S pack using 4 of the above cell holders glued togetherto reach my goal (bus bar setup will not be central)
However I dowantto go higher and so dependingon progress will keepthe idea of a 600P 14S settup in my sights.



image_ylthhc.jpg











Also I have just purchased a spot welder :exclamation: :exclamation: :exclamation:hope this does the job.

https://www.sunkko.net/sunkko-709ad-pulse-spot-welder-for-battery-pack.html






I am wellinto my testing regime... because I am taking my sweet time toget my wall built I decided to set my opus test and charge to 3.7. I have 3d printed the large fan cooling mod and its all working a treat to crank through the batteries.


image_gkbntv.jpg







My free supply of fabulous and near new cells is not a high volume one as I had thought :(

It is only netting me about 300cells peryear. I have resorted to begging for andpurchasing used laptop battery packs like so many others and the results are nasty. the cost is $800 for 100kg of batteries with a return policy for unused cells. not a bad arrangement I think.

anyway here aremy tested batteries so far...


image_pusqlw.jpg



as you can see I have a long way to go but now that I have committed to a layout it should come together more quickly. keen on your input and thoughts.



PS can a mod move this into the DIY battery project builds?
 
I strongly recommend you start off with a smaller battery. 14s432p would be by far the largest pack I've seen anyone build, and I'm sure it will bring with it many unforeseen challenges. Some of the issues I can think of right now:
* Each pack would weigh 20kg, the whole battery 280kg. Mechanical stability of the pack? The shelf? Is it earthquake proof?
* I had to take 1 pack (104p) out for repairs after just 4 months of operation; statistically a 432p would in theory develop issues once a month ;-p. Carefully manhandling a 20kg pack is probably no fun.
* You'd have to harvest and test 6048 cells just to get started. At my rate, I'd need 1~2 years for that many cells... by the time I finish my last cell, I'd probably have to boost charge and test the first cells again.

My recommendation is to build a more modular system that you can add batteries/packs to as they become ready. For my system, I started off with 14s92p, 2 months later added a 14s104p in parallel, going to add another 14s104p in a few weeks. The final target being perhaps 10 batteries in parallel.
I've seen someone start off with a 7s80p system, then extended/glued to that to make it into a 7s120p.
Others start with a 7s system, then later add more packs to make it a 14s.

One more tip: the card boxes the 3d printer filaments come in is perfect for storing 18650 cells. The ones I use neatly fit 125 cells! Makes counting so much easier.
Just make sure to reinforce the bottom with duct tape so that it doesn't fall out.
 
ajw22 said:
I strongly recommend you start off with a smaller battery. 14s432p would be by far the largest pack I've seen anyone build, and I'm sure it will bring with it many unforeseen challenges. Some of the issues I can think of right now:
* Each pack would weigh 20kg, the whole battery 280kg. Mechanical stability of the pack? The shelf? Is it earthquake proof?
* I had to take 1 pack (104p) out for repairs after just 4 months of operation; statistically a 432p would in theory develop issues once a month ;-p. Carefully manhandling a 20kg pack is probably no fun.
* You'd have to harvest and test 6048 cells just to get started. At my rate, I'd need 1~2 years for that many cells... by the time I finish my last cell, I'd probably have to boost charge and test the first cells again.

My recommendation is to build a more modular system that you can add batteries/packs to as they become ready. For my system, I started off with 14s92p, 2 months later added a 14s104p in parallel, going to add another 14s104p in a few weeks. The final target being perhaps 10 batteries in parallel.
I've seen someone start off with a 7s80p system, then extended/glued to that to make it into a 7s120p.
Others start with a 7s system, then later add more packs to make it a 14s.

One more tip: the card boxes the 3d printer filaments come in is perfect for storing 18650 cells. The ones I use neatly fit 125 cells! Makes counting so much easier.
Just make sure to reinforce the bottom with duct tape so that it doesn't fall out.

great input thanks mate. very thoughtful of the size and maintenance of the pack. I will be building it as a 108P - 14S and adding the modules as you say.
 
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