Chuck's 18650 14S120P+1 UK Powerwall.

Announcement - Help us fight the BOTS! Please report all spam including stuff in your inbox!

chuckp

Member
Joined
Jul 29, 2018
Messages
396
jdeadman said:
Looking good. I've processed enough to make my first 2 strings of 7s40p. Still have many cells to process but I'm trying to keep each set of 7s perfectly balanced so when I stack them up the entire wall stays balanced.

That's my plan too, build a fall string ofbalanced packs before starting on another. I've exhausted my supply of cells now, with this set i had to put a couple of lower capacity cells in each pack to make it up to the full 14S40P.
I'll need to get back out and see what I can beg borrow and steal again in the way of laptop batteries.

I have just been offered a shed load of old mobile phone batteries of different makes, been told there is a few hundred of thembut not sure what i could use them for.
 

jdeadman

Member
Joined
Mar 28, 2017
Messages
939
Yea until recently I only had a trickle of packs coming in here locally. I drove 5 hours to pickup a PIP (Powerwall in Progress) that a guy had to give up on for a few reasons. Got a wicked Deal but one these cells are gone I'll be back to pittance.
 

chuckp

Member
Joined
Jul 29, 2018
Messages
396
Hi guys

Just a little update.

I now have processed and assembled 28 40P packs that are good to go these have now been standing for between 3 to 8 weeks and are all sitting between 4.13Vand 4.15V.


image_tfeelk.jpg


Hope that I'll be able to get the inverter soon and get the wall up and running.
 

jdeadman

Member
Joined
Mar 28, 2017
Messages
939
Very Nice. I like the 40p packs. I've started to build my 40p packs and just the sheer amount of soldering is wild. I'm waiting on more solder.

What's your BMS plan?

I'm going to be putting my 40P packs on bus bars for Parallel connections so I can use it as one bank.
 

chuckp

Member
Joined
Jul 29, 2018
Messages
396
jdeadman said:
Very Nice. I like the 40p packs. I've started to build my 40p packs and just the sheer amount of soldering is wild. I'm waiting on more solder.

What's your BMS plan?

I'm going to be putting my 40P packs on bus bars for Parallel connections so I can use it as one bank.

Yeah

I've spot welded the fuses to the cells and soldered to the bus bars.

Eventually I'll fit the batrium, but to start with I'll be using a cheaper Chinese one that I have.

https://www.aliexpress.com/item/14S...h-android-Bluetooth-app-UART/32828948173.html


I managed to get hold of some 2 pole mcbs, two 32A and one 63A all rated for DC. Not sure yet if I'll use them all yet, Imay do two strings and put a 32Abreaker on each and the put both through the 63A.Will make it easier to shut down one string should a pack need replacing.
 

chuckp

Member
Joined
Jul 29, 2018
Messages
396
I have got a these DC MCBs that I think I will use 32A at string level and the 63A between theinverter and common string connection.


image_ciwxcs.jpg

image_xjcnhw.jpg


Now I just need to find a shunt trip that will fit the 63A MCB. It looks very similar to a Merlin Gerin
 

chuckp

Member
Joined
Jul 29, 2018
Messages
396

chuckp

Member
Joined
Jul 29, 2018
Messages
396
A little update, been very busy at work for the last six months or so, not much time to spend on my powerwall.

Anyway received a box in the post yesterday.


image_gjvhxq.jpg

image_dtahba.jpg

image_ahwcpg.jpg


Very excited to see what's inside.


image_mjowti.jpg

image_sikcbc.jpg


Picked these up at a very reasonable price from a firm that was decommissioning a site.

Used but apparently in good working order.

Thought is they will make a great ATS. I'm hoping i will be able to use them in the event of a power cut to keep the battery charger/inverter running and make it work off grid.

The charger/inverter I'm ordering is the Sofar Mass Energy ME3000SP, although this has a facility for EPS critical loads, the plan is to keep the whole house powered from the powerwall should the grid fail.

I'm hoping that the contractor will switch fast enough the inverters won't notice the the grid is off and stay on.
Think I'll also add a time delay relay on the grid control side to prevent the contactor banging in and out on momentary power cuts, and try and limit any surge when switching back to grid.
 

chuckp

Member
Joined
Jul 29, 2018
Messages
396
I might need me a Daromer to help get my head around the control circuit. Figuring out how to trick the grid tied inverters into thinking the grid is still connected when its not.
 

chuckp

Member
Joined
Jul 29, 2018
Messages
396
Yeah

I've ordered my Sofar Mass Energy ME3000SP AC Coupled charger inverter.

So excited to get it all up and running.
 

chuckp

Member
Joined
Jul 29, 2018
Messages
396
Yeah

Another box has arrived for me.


image_vmseni.jpg


My new Sofar ME3000SP charger inverter has arrived.


image_nrjxyl.jpg

image_iaulbq.jpg


Looking good.


image_mfkzff.jpg

image_uwteml.jpg


Now to get it out up and running.
 

chuckp

Member
Joined
Jul 29, 2018
Messages
396
Sean said:
Any particular reason you didn't go for the KTLM ?

I think thats a solar inverter only, the ME3000SP is an AC coupled bidirectional charger/inverter.
Would have preferred something in the 5-7 kW range but I couldn't find anything else that would suit my tight budget.
 

chuckp

Member
Joined
Jul 29, 2018
Messages
396
Little update, work has been manic, not had much free time to spend on the wall but a little more work has been done.

Sofar ME3000SP is now hung on the garage wall.


image_xzldhi.jpg


Still need to install the critical loads board and wire back to the inverter.

Builder has been organised to come and build the battery house outside on the opposite side of the wall behind the inverter.

Busy printing mounts for the cell packs 20/28 printed so far. STL file, thanks to AZ Tekkie on Thingyverse. I won't be using the top mount as my packs are small enough not to require them.


image_dxlvwt.jpg

image_wgjqhj.jpg


image_ajzhue.jpg

image_uhdewk.jpg


Started work on the main busbars for the cell pack series/parallel connections.
I still need to finish the heat shrink and fit the clamps to 15 bars for the 28 x 40P packs built so far. You should get the idea from this pic.
There will be enough clamps for another 28 cell packs to be added at a later date.


image_qxmjxr.jpg


Plan is to make it as easy as possible to pull a pack and replace it if/when required.

BMS monitoring leads will be connected to the top of each rod (eventually when funds permit it will be replaced will Batrium). Thinking about using a 15 core cable through the wall into the garage and mounting the BMS in an enclosure under the inverter. Unless theres any reason to have the BMS directly above the battery? I will need to extend the monitoring leads either way.
 

chuckp

Member
Joined
Jul 29, 2018
Messages
396
Making progress with main busbars, 15 bars heat shrink sleeved with clamps ready to go.
Started to add link cables for pack connection.
Ran out of crimp lugs will need to pick some more up tomorrow, but cables are prepped with Anderson plugs.

Need to chase builder and find out when he's coming to build the battery house.


image_togqjv.jpg
 

chuckp

Member
Joined
Jul 29, 2018
Messages
396
Made a start on my little battery house.

Ground cleared


image_cgysxc.jpg


Slabs down


image_jxkgrt.jpg


Walls up


image_gzztff.jpg

image_upyfpi.jpg


Roof on and back wall boarded over. Busbars up ready for the packs.


image_ctjllp.jpg


BMS monitoring wires pulled in ready to be crimped to busbars.

Pack mounts going up tomorrow, I need to make the doors and fit them before putting the packs on their mounts.

Hoping to have an operational Powerwall by the end of the week.
 

chuckp

Member
Joined
Jul 29, 2018
Messages
396
BMS cell monitoring wires connected up.


image_ssosdl.jpg

image_ebxgyn.jpg


Pack mounts started going up.


image_xaoleb.jpg

image_lgjexc.jpg

image_xbhggp.jpg


Packs mounted and connected to the ME3000SP.

Was starting to get dark and beginning to rain, had to put the doors up a bit rapid so no pics of the packs mounted yet, maybe over the weekend if the rain stops long enough.

Still to sort out an issue with getting the ME3000SP talking to the BMS, not sure how this is going to work out at the moment.
 

chuckp

Member
Joined
Jul 29, 2018
Messages
396
ajw22 said:
Very neat!
I've had seemingly rock solid 3d printed parts fail out of the blue after months of being under tensile stress. Maybe add some sort of backup clamp or strap as insurance?

Thanks for the heads up.

I have some metal L brackets that would fit in the recess on the underside, they would make great additional supports.
 
Top