Thread Rating:
  • 0 Vote(s) - 0 Average
  • 1
  • 2
  • 3
  • 4
  • 5
10kwh 18650 Powerwall in Nigeria
(08-06-2017, 08:06 PM)Korishan Wrote: I can't exactly tell from the pics, for the connections between packs, are the lugs touching each other and then bolted, or are they connected Bolt-Lug-Nut-Lug-Nut? And, what kind of bolt are those; galvanized, zinc plated, silver plated, stainless steel?
If the nut that is in between the two lugs is silver plated, copper/brass, or nickel plated, then it'll probably be ok. But if they are zinc plated, stainless, or galvanized, then you are going to loose a lot of power right there. If not for differing metals causing electrolysis (moisture in the air contributing), but high resistance in the SS and Galv.

Now, if you connect it so that they are Bolt-Lug-Lug-Nut, then it wouldn't matter what the bolt/nuts are made from as the current would go from lug to lug without effecting anything else.

Korishan,  Thanks a lot for your contribution. The arrangement is Bolt-Lug-Nut-Lug-Lug-Nut. And you are absolutely right about the electrolysis thingy because I can already notice corrosion on the nut in-between (the same nut that I need to take out to improve conduction). 
The reason I added the nut in the first place was to act as a spacer. The lugs on the first pack has very little flex (literally no cable extension - see image)
Without the nut there will be no space in-between the packs. I wonder if I can get a copper or brass nut and I don't have the luxury of desoldering any of those batteries for now. 
I will definitely look for a work around.

(08-06-2017, 08:27 PM)daromer Wrote: If you have problem with tearing the soldered fuse wires apart when working with it there is 2 things you can do if you ask me:
* Don't hook it up until its perfectly aligned so you wont disturb the fuse wires
* Secure the ends so some movement wont cause any issues or just attach longer wires/busbars so some flex can be given.

I do both here on my packs.
Thanks Daromer for your suggestions. I will definitely make the busbars longer to have more flex.
Your candle looses nothing by lighting another! Cool
Yeah, a brass nut, or a brass bushing, would work fine. The bushing would probably be easier and cheaper to get
Proceed with caution. Knowledge is Power! Literally! Cool 
Knowledge is Power; Absolute Knowledge is Absolutely Shocking!
Certified 18650 Cell Reclamation Technician

Please come join in general chit-chat and randomness at Discord Chat (channels: general, 3d-printing, linux&coding, 18650, humor, ...)
(this chat is not directly affiliated with SecondLifeStorage; VALID email req'd)
I considered to have something in between to but i skipped it and had the wire to be bent so they fit together without. less resistance and stuff.

But if I would have done it i would have used copper tubing that fits over the nut directly and acts as bus.
Korishan likes this post
The Ultimate DIY Solar and build place
YouTube / Forum system setup / My webpage  Diy Tech & Repairs

Current: 10kW Mpp Hybrid | 4kW PIP4048 | 2x PCM60x | 83kWh LiFePo4 | 10kWh 14s 18650 |  66*260W Poly
Upcoming: 14S 18650~30kWh | Automatic trip breakers, and alot more
Installed my 3rd KWH pack some weeks ago. 7 (Seven) more kwH to go.

I finally removed all the nuts in-between. I extended the length of the bus bars to allow for more flex, besides there are six cable lugs between the bolt and nut so the packs have some space in-between.

My next build will be a 2kwh pack (40P7S) to make my total storage 5 kWh.
mhoungbo, Wattsup, Herbie like this post
Your candle looses nothing by lighting another! Cool
very nice setup, congrats Smile . Why are you using MC4 connectors? From my experience, they're easy to close but hard to open (sometimes even with a special tool) and quite expensive compared to other solutions...

Cells tested: 5.964 (overall: 11.759 Ah, average: 1.971 mAh)
Cells in production: 2.940 (overall: 6.174 Ah, average: 2.100 mAh)
Wall bank: 7s420p, 882 Ah, 21 kWh
Project page
Live solar/powerwall values
Daily graph
Hopefully I am wrong, but why are your Batteries between 4,34V and 4,53V?
max. Voltage for a cell is 4,2V!
I have now added more packs to my cells.

Total size is now 5kwh.

(09-26-2017, 09:41 PM)owitte Wrote: very nice setup, congrats Smile . Why are you using MC4 connectors? From my experience, they're easy to close but hard to open (sometimes even with a special tool) and quite expensive compared to other solutions...

Sorry for the late reply. I have been offline for a while. 

All what you have said is entirely true. I actually used the MC4 Connectors because I have so many of them, no other reason in particular. 

I have since resorted to using cable lugs.

(09-27-2017, 12:58 PM)PAF Wrote: Hopefully I am wrong, but why are your Batteries between 4,34V and 4,53V?
max. Voltage for a cell is 4,2V!

You are perfectly correct! It's the mini voltmeters that are giving a wrong reading. 

Unfortunately they are not the type that can be calibrated.

They are about 0.3v higher than the actual voltage, so I just use them to have a general idea of where the voltage is.

I have replaced them with more accurate ones that can be calibrated.
Your candle looses nothing by lighting another! Cool
Now that's something! What did it cost you to get the batteries?
I find its expensive here in Port Harcourt...

do you plan to use a BMS for your system ?

Who read this thread?
100 User(s) read this thread:
hbpowerwall (02-05-2019, 03:39 AM), Chickey (07-20-2017, 01:19 PM), pacm31 (09-27-2017, 01:01 PM), daromer (01-29-2018, 06:21 PM), mike (02-05-2019, 12:24 AM), goodnowm (12-27-2017, 03:59 AM), BigBen (01-30-2018, 05:01 AM), Joaquinsfy (02-09-2019, 08:48 PM), SJBW (07-16-2017, 05:56 AM), NiVa (01-04-2018, 10:29 PM), Lux_Gamer (07-17-2017, 07:05 PM), owitte (09-27-2017, 11:40 PM), opus40 (07-15-2017, 11:37 AM), Loboosh (09-27-2017, 11:49 AM), Majorphill (09-27-2017, 07:50 AM), riveracc1 (08-10-2017, 03:09 AM), coolfx (08-07-2017, 01:29 PM), JustJim (12-26-2017, 02:31 AM), Korishan (02-05-2019, 12:48 AM), A + A (09-26-2017, 09:57 PM), PAF (02-06-2019, 09:46 AM), Wattsup (11-28-2017, 04:07 AM), eeesOap (09-28-2017, 04:30 PM), Frnandu Martiński (01-09-2018, 02:10 PM), eAnic (12-18-2017, 03:18 PM), Sabado (02-18-2019, 07:58 PM), jdeadman (01-29-2018, 05:55 PM), charlie246 (09-27-2017, 07:41 PM), camils (01-30-2018, 01:40 AM), 2146 (01-29-2018, 07:10 PM), wim (02-05-2019, 07:08 PM), wimpie007 (02-05-2019, 10:38 PM), ericg (01-03-2018, 03:21 PM), frnandu (09-30-2017, 03:40 AM), melsom (04-14-2019, 10:16 AM), typ49 (07-17-2017, 07:43 AM), The-J-Man (07-17-2017, 06:05 PM), Hellonasty (07-19-2017, 04:31 AM), Christian (10-25-2017, 09:15 PM), Charles Francis Speakman (12-03-2017, 10:00 PM), Jeremy Choy (07-15-2017, 09:54 PM), 1958 greyhound (08-08-2017, 11:25 AM), Abarth595 (08-07-2017, 07:24 PM), kktuo (09-26-2017, 09:53 PM), neilmc (08-07-2017, 10:54 AM), Off Grid Power wall (09-27-2017, 09:15 AM), Tychipowerwall (07-15-2017, 12:34 PM), rebelrider.mike (02-02-2018, 09:11 AM), kaits31 (07-16-2017, 11:45 AM), watts-on (02-05-2019, 09:18 AM), Dan Lim (01-10-2018, 08:19 AM), jesusangel (12-03-2017, 09:21 PM), Hanssing (09-27-2017, 04:46 AM), autobd (08-06-2017, 10:46 PM), IronSky (02-04-2019, 06:29 PM), Mark Daniel Olsen (12-15-2017, 08:38 AM), DrkHrs13 (07-16-2017, 07:06 PM), silverse2m6 (07-15-2017, 12:03 PM), kot (03-13-2018, 07:14 PM), ismaildoganw (07-17-2017, 02:00 PM), kazbach (07-15-2017, 04:04 AM), Stefaan De Ridder (01-29-2018, 06:46 PM), fin020 (07-16-2017, 12:28 AM), Chicken (07-15-2017, 08:07 AM), Inverted 18650 (07-15-2017, 11:50 AM), Lawcomleo (11-27-2017, 10:15 PM), josephchrzempiec (08-12-2017, 01:43 AM), BlueSwordM (08-07-2017, 02:57 PM), Piotr Dziel (08-23-2017, 05:31 PM), Johnny Stauersbøl (07-16-2017, 06:37 PM), Dennis Van Hoek (08-07-2017, 08:03 PM), James Lane (07-29-2017, 03:27 AM), Happy Camper Homesteader (07-16-2017, 11:04 PM), pruesel (07-30-2017, 02:12 PM), Stew Mohr (08-07-2017, 12:46 PM), Jesse Osborn (07-15-2017, 01:01 PM), Nitroghost (12-09-2017, 06:10 PM), John.Siler (07-17-2017, 11:29 AM), Tonda Zeman (08-09-2017, 09:16 AM), nokia6110nav (07-29-2017, 10:11 AM), KaminoReal (01-29-2018, 06:04 PM), Shade (11-28-2017, 12:33 AM), barthy (08-10-2017, 06:52 PM), Pyro (08-06-2017, 10:34 PM), Daveyboy (08-07-2017, 08:45 PM), al4sound (03-08-2018, 01:20 AM), Seedser (12-10-2017, 07:24 AM), E.Lines (11-01-2017, 07:19 AM), paraskevas (01-04-2018, 10:23 AM), Mazlem (02-04-2019, 03:33 PM), kiwi (10-30-2017, 02:52 PM), Timothy_Hennessy (08-10-2017, 01:58 PM), ivnz (09-26-2017, 08:34 PM), iofosho (12-09-2017, 11:40 AM), VEmpire (09-28-2017, 09:20 PM), Geek (02-05-2019, 01:06 AM), harrispp (11-28-2017, 12:25 AM), Rad (10-05-2017, 09:13 PM), (09-27-2017, 02:10 PM), WildCard_25 (09-30-2017, 10:28 AM)

Forum Jump:

Users browsing this thread: 1 Guest(s)