Topband Navitas Prismatic at BH

[sshibly]

Interesting design, what are the cons of using
"Parallel BMSs"? won't one battery backfeed another if they are equal to start with?

Update:
I tested on cell:

1. The cell came with 90% SOC charged, shocked kinda.
2. The cell pulled 24.5 AH easy and still had over 3 volts, while discharging at 12 A, right at the end the voltage sagged to around 2.9V

I give BH 3 gobi ratings (outt 5), lost 2 gobis for price, kinda $$$ for Amp Hours, EVE being the bench mark. I can putt 280A out of Eve cells max without breaking a sweat .

FYI: the volts displayed is INACCURATE,

 

[Horsefly]

Just FYI, I guess these are back in stock. I just went to the website and the description still said they were sold out, but the button no longer said sold out. It let me put in a quantity 8, so I went ahead and placed the order. I'll update here if the order eventually gets bounced or delivered.

 

[DiyMegs]

Lol I couldn't order anything ?. Guess they only had a hand full??

 

[Horsefly]

Lol I couldn't order anything ?. Guess they only had a hand full??

Well, that's odd. When I saw your post I went back and it again let me put 8 in my basket. I didn't want 8 more, so I didn't try to complete the sale, but I wouldn't think it would let me get that far if they were out.

 

[DiyMegs]

Well, that's odd. When I saw your post I went back and it again let me put 8 in my basket. I didn't want 8 more, so I didn't try to complete the sale, but I wouldn't think it would let me get that far if they were out.

Mine keeps reducing the order to 1 or 2 cells at checkout ?

 

[Horsefly]

Sounds like they had 10 cells, and I bought 8. Sorry about that.

Edit to add: I forgot to mention, I did complete the first order, and got the confirmation email from BH.

 

[DiyMegs]

W

Sounds like they had 10 cells, and I bought 8. Sorry about that.

Edit to add: I forgot to mention, I did complete the first order, and got the confirmation email from BH.

Your good ? congrats on your cell purchase!! Lol Lord knows I don't need anymore ?

 

[hour]

I received my cells a couple of days ago and need to give some thought to 12v pack assembly. Since I'm not intending to draw any more than 100w from the pack (giant macbook external battery), is there any dirt simple solution for bus bars? Like flat aluminum bar from Home Depot? Perhaps a roll of the thickest nickel strip I can find with holes punched or drilled for studs?

 

[DiyMegs]

I have been wondering the same thing Hour. I've been searching the internet relentlessly. Thus far I have found (IMO) two possible solutions.
1. Amazon has https://www.amazon.com/gp/aw/d/B07XNNZ95Q/ref=ox_sc_act_image_3?smid=A2C2NCPLSSHH6K&psc=1&th=1 they're nickel plated copper bus bars with 5mm instead of these cells 6mm; originally designed for various hybrid vehicles and as such each package has a different number of bus bars. Idk what do you think?
2. Metal super markets store. They seem to have great deals and lucky I have afew local to me.

But I'd love to see what the group has for suggestions!!

 

[Horsefly]

I know it's been said before: copper pipe, pounded flat, cut to length, and then holes drilled. Since my little 24V 8s set will be just to play with, that's what I'm going to do.

 

[Horsefly]

My 8 cell order has shipped. FedEx says it will probably be here Friday. I seldom trust Fedex though, so I won't get overly excited and wait at the door all day.

 

[Shrtbus]

I know it's been said before: copper pipe, pounded flat, cut to length, and then holes drilled. Since my little 24V 8s set will be just to play with, that's what I'm going to do.

Was going to say the same, David made some lugs for his post in the video but making it flat all the is easy.

 

[hour]

I've done the flattened copper pipe thing on another build but that was before I read of people sanding and polishing their terminals. Is there a reason beyond price that we don't order copper bar online and use that? Doesn't seem like a bad investment to get a couple feet for this project and whatever comes next if it sits flush and doesn't require hammering. Balance issues really suck when trying to test the quality of your pack and I'm on the understanding that people have resolved reported imbalance by sprucing up their connections, things as little as polishing. Surely something starting off flat will do better than garage floor textured pipe after being whacked on.... r-right?

 

[Horsefly]

I've done the flattened copper pipe thing on another build but that was before I read of people sanding and polishing their terminals. Is there a reason beyond price that we don't order copper bar online and use that? Doesn't seem like a bad investment to get a couple feet for this project and whatever comes next if it sits flush and doesn't require hammering. Balance issues really suck when trying to test the quality of your pack and I'm on the understanding that people have resolved reported imbalance by sprucing up their connections, things as little as polishing. Surely something starting off flat will do better than garage floor textured pipe after being whacked on.... r-right?

Sure. It's up to you. I mentioned above that this pack of little cells is - for me - just something to play with. When I eventually pull the trigger on 8 280Ah cells for my cabin, I almost certainly won't use flattened pipe. But for this pack, it's good enough.

 

[sshibly]

the post nuts are:

M6x1.0 Flange nuts work best
Lowes - NOT IN STOCK in my area, order online to pick them up
Homedepot - had them, 70 cents for 2 pack.

 

[Horsefly]

the post nuts are:

M6x1.0 Flange nuts work best
Lowes - NOT IN STOCK in my area, order online to pick them up
Homedepot - had them, 70 cents for 2 pack.

Good to know. Thanks for that.

 

[sshibly]

bus bars -
Grainger rocks for copper flat stocks and FREE shipping to your local store. I picked up this one, 1/8 thick and bit less than 1/2 inch wide
and [drum roll] 6 ft long, yes 6 ft, you can make many many many [insert police academy ....] bus bars.

 

[sshibly]

Grainger item# 2AAB5
is what I am getting to make bus bars and impress the ladies ;-)

 

[snoobler]

Got my 4 a couple days ago as well.

All were 3.29-3.30. As-received discharges showed in 11.2-13.8Ah stored.

All recharged to within 240mAh of each other and right around 25Ah.

Comparative IR checks were within 10% of each other.

Pleased.

So cute.

 

[Horsefly]

So cute.

There's some words you don't expect on a DIY Solar forum.