German Powerwall #X (the most western)

cadric

Member
Joined
May 3, 2018
Messages
107
Hi Guys,

As I'm not the type of guy to present work, that is not in a certain stage, I waited for my Presentation to the point that at least a minimal system is running.

So now I'm proud to finally present my first Step of a DIY Powerwall from Lithium 18650 Cells.

After around 18 months of learning, struggeling and redoing I now have my PW running for nearly one month without any issue so far.
After one cell exploded in my basement in the beginning, I had to build a small shed outside to keep my home save. I wrote about it earlier.

Although I build my Battreriy packs the same way as most of you, my capacity is not exactly compareable to all your solutions,
because as I only use the cells between 3.5 to 4 Volt I therefore only checked them for capacity between 3.5 and 4 Volt.
So my first Step is now 14S60P with a capacity of 80AH netto, which means I can fully use this 80Ah and still keep my cells between 4,0V highestand 3,5 V lowest.

I begann with Laptop Batteries from ebay, as a lot of you did, but soon I realized that this is getting far to expensive.
Nearly 2/3 of all cells were not useable anymore. My lowest level was 1000mAh for using though.

Luckily I found a source for e-bike batteries and these are mostly very usefull. It is realy seldom that the cells are kaputt, mostly it was the BMS up to now.
Only draw down is the black flexible mass they are stuck with, but I now think I found a solution for extracting the cells, without destroing them.
I showed that in another thread.

I'm now in building the second step of cell packs but I only have tested around 420 cells and still haveto go through at least another 450.
It's still a work in progress as I for example want to add more security items to the system.
For example I added a fan to the shed to suck out the hot air and I added a fresh air channel to my two Inverters, so that they get cool air from outside.
I will evtl. add a cooling cirquit to this air channel if it still gets to warm inside by using the water cirquit from my pool as the pump is directly beside the shed.
I already have a heat exchanger form a VW golf lying arround for this which I plann to put before the fan from outside of the shed
But that is planned as improvment for next year.

I want to thank all of you who supported me on this adventure...

here are some impressions of my solution:

My Shed:

image_sywrod.jpg


Connecting Cabinett:

image_hpxinx.jpg


My Inverters with Air Supply, Batrium etc.:

image_nejcbn.jpg


And my 1st Battery Bank 14S60P with Batrium Longmons:

image_ulbtof.jpg


My Charging Cabinett: ( blur, but to get the idea)

image_rcxagf.jpg


My Software:

image_mpsild.jpg


I want to add an additionanl BMV 700 from Victron to the system, because with SolPipLog I can stear charging regarding to the SOC with this BMV.

At the moment only the garden is powered by the system, but when I reach at least 20kWh of Battery Power,
I will try to power my house from the system.
Connections are all established already, so I'm only waiting for enough cells.

Regards

cadric
 

jdeadman

Well-known member
Joined
Mar 28, 2017
Messages
926
Very Nice. As I am still developing my system I need a Wiring cabinet.
 

richie241

Member
Joined
Nov 6, 2018
Messages
34
Hi Rene ;-)

Nice to see your Project - im also in the building process. Keep on testing.
Maybe i can visit your in the near future.

Viele Gre
Richard
 

cadric

Member
Joined
May 3, 2018
Messages
107
Hi Richard,

thanks, yes finally running after 18 month of preperation.
Saw your Projectsite just recently. Looks very professional.
I need to upgrade my Shed already for next steps of Batteries as it is already to small.
We can schedule via WA.


Regards

cadric
 

cadric

Member
Joined
May 3, 2018
Messages
107
Hi Guys,

a little update from my side:
I added a seperate shed to the back of my existing one to put all batteries in, because the first shed is finally getting to small.
My 2nd Bank of 840 cells is nearly ready to be installed, so I will have two seperate banks 4kWh for to start.


image_ojykih.jpg

image_ljcvaq.jpg


regards

cadric
 

stevelectric

Member
Joined
Nov 2, 2018
Messages
45
Hi Cadric,

nice cabinet and well insulated. Are you going to put a heater inside for winter times, or just shut off everything until temperature are above freezing level? My cells are still inside because they like the same temperatures like myself :D

Gre
Stefan
 

chuckp

Active member
Joined
Jul 29, 2018
Messages
340
Hi Cardric

Project looks great. I too have my powerwall outside the house. Not that Ive had any problems with exploding cells. More because they are reclaimed cells and even though Ive tested them I dont know how abused they have been before Ive started using them.

Im up to 13+kWh now and my system is running great. Still got a good ways to go before Ive reached my ultimate goal of 35-40kWh though.

Anyways good luck with the rest of your journey.
 

cadric

Member
Joined
May 3, 2018
Messages
107
stevelectric said:
Hi Cadric,

nice cabinet and well insulated. Are you going to put a heater inside for winter times, or just shut off everything until temperature are above freezing level? My cells are still inside because they like the same temperatures like myself :D

Gre
Stefan
Hi Stefan,

sorry for my late response. Projects on the job are really taking very much time.
At the moment I'm not sure how the temperature will develop in the new shed next Winter.
Last Winter the temperature in Shed 1 was on some days to low for working inside, although it's isolated with 6cm Styrodur.
But summertime is also not very good sometimes shed one gets really warm.
So for cooling in summer I installed two fans:
One that gets cool fresh air from outside to the invertes in the first shed and
an additional one that exhausts the warm air from first shed produced by the Inverters to warm up the new Battery shed.
Also as I have a pool pump directly beside the shed, so if it get's to warm for the inverters I will be able to add a car inverter in front of the fan,
to get more cool air to the Inverters. But that is still future music.

To control the temperature in the Battery shed I have a temperature sensor installed.

So I really am curious how next Winter will be. Maye I will shut the System down in December/January because in that time there is noit much output.
Even with my 16.5kwp System I get max. around 250 to 350 kwh in this time.

Regards

cadric


chuckp said:
Hi Cardric

Project looks great. I too have my powerwall outside the house. Not that Ive had any problems with exploding cells. More because they are reclaimed cells and even though Ive tested them I dont know how abused they have been before Ive started using them.

Im up to 13+kWh now and my system is running great. Still got a good ways to go before Ive reached my ultimate goal of 35-40kWh though.

Anyways good luck with the rest of your journey.
Hi chukp,

thanks.
Exploding cells was exactly why I put everything into a shed outside.
One of all cells tested exploded in the beginning while I was in bed and it was resting after the loading process although I have the SKY MC3000 with temerature sensor for best security. That was a lesson learned. When something burs, at least it will burn 3 Meters away from my house.
Still I have to install alarm systems for this occasion.

My next 4kw netto (14S60P) are just on the step to be added to production.
Because of corona I was not able to get more cells, so no I'm on my last e-bike Akku to be taken apart.
From the number of cells I think I'm at around 2500 useable ones.

regards

cadric


OffGridInTheCity said:
Nice bit of work - Thanks for sharing details!
Thanks,

still a long way to got to get minimum 20kwh of storage.

cadric
 

cadric

Member
Joined
May 3, 2018
Messages
107
Good Evening Gentlemen,

after a long time now yesterday I finally had some progress with my Powerwall.

Before I had to pimp my shed a little bid:
I widened the doors, to be able to access each package in the shed and added a sixth layer to the shelf,
so I can upgrade each bank 2 times.


image_gnkzkt.jpg




LastWeek I added Watercooling to my System:
The Fan which is cooling the Inverters now has a heatexchanger installed that is connected to my Pool watercycle,
place directly beside my initial shed.




image_wmhlax.jpg

image_rsphre.jpg



Then I finally added the second Battery bank to my Powerwall, again 840 recycled cells, but this time around 90Ah capacity.
So in sum I now have min. 160Ah of capacity for my system.

Downside is, again one Longmon died in this process.
I already ordered 3 new items, I hope this will not happen to often.

So for the time until they are delivered, I have to stick to my first bank only.

May Sunpower be with you ;)
 

reviewmirror

New member
Joined
May 18, 2020
Messages
3
Chapeau! Very nice.
That is exactly what I am looking for.
One question: Didn't you suffer from moisture in the shed?
I mean there is no Airconditioning except from temperature control, am I right?
I am looking for these in wall AC's and I found some from itlay, distributed via banggood for around 250 bucks.
My initital idea was to use Peltier but this draws a lot more power then real AC and also does not regulate the Humidty.
Still trying to figure out what shed I should build. Thinking of pure steel/metal only in case of emergency with fire outlets for each module (13S15P).
At the moment I am soldering DIYBMS V4 and there is a looong way to go. :)

Cheers and stay healthy
Alex
 
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