Discussion - Cases for aluminum cells

[upnorthandpersonal]

You can get them in several places, for example here (which is where I took the image from):
https://www.copperbraid.co.uk/busbar-braids/

You can also find them on Alibaba and other suppliers. Just search for 'braided bus bar' or 'braided copper'. I tend to make mine myself with copper braid as a starting point and press-fitting copper lugs for example. I made a small insert for a vise so I can press fit copper braid into a piece of copper tube.

 

[Bob B]

You can get them in several places, for example here (which is where I took the image from):
https://www.copperbraid.co.uk/busbar-braids/

You can also find them on Alibaba and other suppliers. Just search for 'braided bus bar' or 'braided copper'. I tend to make mine myself with copper braid as a starting point and press-fitting copper lugs for example. I made a small insert for a vice so I can press fit copper braid into a piece of copper tube.

Got a picture of one of your home made ones? Seems like they would be a lot less susceptible to vibration in a mobile environment.

 

[upnorthandpersonal]

Got a picture of one of your home made ones?

Not at the moment, sorry. I'll make some pictures next time I make them (which should be as soon as my 32x 280Ah cells arrive). I'll make a bunch for those...

 

[BigVT]

Those look nice indeed! Are there any downsides to just use short and appropriate sized cables instead of bus bars?

 

[Fish Freak]

I've shared this in another post.

I took a lot of liberties with the Fortune battery design and some Lego inspiration to design and 3d print my own top and bottom supports that I plan to glue to the 280ah cells. I then plan use 1/4" threaded rod to bolt 4 cells together into either 2 12v batteries or one 8 cell battery (haven't decided yet). I will probably use angle brackets to bolt to camper floor.

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I plan to design another cover to allow a BMS to easily mount and have slots for the wires to pass into the top supports. I'm leaning towards the Chargery BMS. I hope to place my cell order next month.

You right there, Heap64, you win the PRIZE for the best connection system copied from Fortune cells! You got everything, cooling air space, clamp holes for the allthread, protection for the terminals, and light-weight and simple for me. Loved playing with Lego's, so that makes yours even more fun! Who knew they might have some practical purpose later in life?!

What would be super cool is some splash resistant container Lego'd to the top for the bms, then I wouldn't even need to buy a case! Heck I'll put the bms in an upside-down see-thru Tupperware container, drill wire holes, silicone 'em up, ought to be good for now?

Any chance you'd share that cad file? I'd need to modify it for the size of my smaller 120Ah, 150Ah cells, which I haven't even picked out yet, but that's no biggie!

I'd need a way to mount or strap down the entire battery assembly, keep it from walking away. Might just try a marine battery tray with nylon web strap and call it good.

Did you ever place your order?

 

[Heap64]

With the covid-19 I've decided to hold off a bit on this purchase. Im pretty new to Fusion 360, I doubt my drawings will easily redo with measurement changes for your batteries. I'm still learning.

 

[bostonbuzz]

Well it’s a bit crowded but I fit it all in the pelican case. The relays used too much energy for my application (50w panel just to keep it topped off and slowly recharge over a week for the next weekend).

I went with monster bluesea latching magnetic relays. I used used ones off eBay of older models for under 100$ each. This gives me the emergency ability to lock them ON so that I can start the engine on the boat if the BMS has a fart - last thing I care about is battery health in an emergency.

I made my own bussbars with tin plated copper.

Bluesea thru-panel terminals, one for charge and one for discharge. Plan on a peak of 200A for engine starting for ~2s.Went with a fancy shunt and will remotely place the chargery screen.

Batteries are sandwiched between 1/4” plates of G-10 (as strong as aluminum and non-conductive) with 1/4” threaded rod. The bottom two go through the case and have large washers with rubber washers to make it mostly watertight. The g-10 is cut so it conforms with one of the sides of the case, and being secured the other ways it should be good for my sailboat being placed in the center of the boat and be able to handle a knockdown and some boat bashing.

 

[upnorthandpersonal]

Got a picture of one of your home made ones? Seems like they would be a lot less susceptible to vibration in a mobile environment.

I've got a new roll of copper braid:



I'll try to make time this week or week-end to make some new bus bars and take some pictures. Maybe I'll make a video, if I manage and if it would make sense. The copper in the picture is so called super-flexible braid and rated 25mm^2 (25mm wide x 2mm thick) good for 150A.

 

[upnorthandpersonal]

I posted a picture some time ago of a quick and dirty concept since I did not have time to make them before. Below are the actual flexible bus bars as I make them. These three actually go to a member of this forum who expressed interest.

 

[Fish Freak]

I posted a picture some time ago of a quick and dirty concept since I did not have time to make them before. Below are the actual flexible bus bars as I make them. These three actually go to a member of this forum who expressed interest.

Nice. Is that smashed 1/2" copper pipe and the braid with no soldier or dielectric grease in the joint?

 

[upnorthandpersonal]

Nice. Is that smashed 1/2" copper pipe and the braid with no soldier or dielectric grease in the joint?

Compressed (in a vise) annealed copper pipe (18mm outer, 16mm inner diameter - 0.71 inch outer, 0.63 inch inner or thereabouts). Width of the bar is 25mm (1 inch) and handles 150A.

 

[turbodave]

You could use a braided bus bar like this:

upnorthandpersonal:
Interesting:
Thanks
Dave

 

[Frank in Thailand]

So happy for you that you have this locally available!!

If I could buy this I probably wouldn't do all the trouble of melting copper and making molds

Off grid and deep down in rural Thailand area have it's benefits and challenges.
Not being able to buy "simple" things like this, is one of them.

Having no Corona infection for many miles is an other ?

 

[Zil]

So much wastewords arguing about stationary when the question was mobile.

 

[upnorthandpersonal]

So much wastewords arguing about stationary when the question was mobile.

I thought the question was on mobile/marine/harsh environments (i.e., all three separate, not harsh mobile marine applications)
These definitely include stationary applications. Besides, braided copper is exactly suited for mobile applications since it negates any stress from vibrations etc. on the terminals and connections that a normal solid bus bar exerts.

 

[Metalophile]

I'm planning a solar system to go in my garage next to my deep freezers, but the case won't be as sophisticated as a Pelican case. I've got some unused inexpensive ice chests. I think I can use that as a battery box, and maybe it will keep my battery from getting too cold on one of those rare but quite chilly cold snaps. Plus, since I think I want to make a fairly large battery, I think the two handles will be good for 2-person lift if I need to move it. Or else I use my more expensive ice chest that has wheels and a handle built in.

 

[sduser]

Figured I would post here instead of starting a new thread. I have read all of the Pelican case threads to get some ideas, but I would like to get opinions on mounting 8 of the EVE 105Ah aluminum prismatic cells in a injection molded plastic case.

I don't have much space to to work with, but it looks like I can fit either the Pelican 1400 or Reed R8888 (or similar sized case).

The cells will barely fit with mm to spare. Is there any issue with mounting these cells in a tight space like this? I would be a sealed environment with no ventilation. For compression I would have to figure something out, maybe tape them well and wedge them in somehow. Very similar I imagine to how the drop-in replacements like Renogy and Lion Energy are done.

 

[Frank in Thailand]

Looks like a good idea.
Ventilation is not really needed, depending on your charge and discharge.
High Amperage is higher temperatures!
For solar use, it should be OK.

 

[HaldorEE]

I am using a 40mm Ammo can for LG LiNMC based battery pack I am building. These are painted, heavy wall steel cans with very secure lids on top and thick rubber gaskets. Dimensions are 5.5"W x 17.25"L x 9.5"D.



I paid $35 plus shipping for one in new condition from Quadratec, a Jeep aftermarket supplier. Because my total order ended up over $50 I got free shipping too.

Quadratec 40mm Ammo Storage Can

Brand New Olive Drab Mil Spec (MIL-B-3060E) Ammunition Cans are the same style boxes that are being used by U.S. and NATO forces around the globe. They have hundreds of uses around the home, garage, shop, range and trails.

www.quadratec.com

There are a bunch of different size ammo cans available. I would figure out what dimensions you need then pick one that works. Quadratec also sells 7.62 and Fat 50 cans.

The Fat 50 might work better with aluminum cased cells. Dimensions are 6.7"W x 12"L x 8.5"D.

Quadratec Fat Fifty Ammo Storage Can

Brand New Olive Drab Mil Spec (MIL-B-3060E) Ammunition Cans are the same style boxes that are being used by U.S. and NATO forces around the globe. They have hundreds of uses around the home, garage, shop, range and trails.

www.quadratec.com

The 7.62 Ammo can could be good for building up smaller batteries from cylindrical cells. Dimensions are 3.5"W x 10"L x 6.75"D.

Quadratec 7.62mm Ammo Storage Can

Brand New Olive Drab Mil Spec (MIL-B-3060E) Ammunition Cans are the same style boxes that are being used by U.S. and NATO forces around the globe. They have hundreds of uses around the home, garage, shop, range and trails.

www.quadratec.com

 

[HaldorEE]

Because of safety concerns with LiNMC cells I am opting for passive cooling using a pair of these Dell Server CPU coolers I bought off Ebay. I will be mounting copper plates on either side of my cells and cutting holes in the sides of the ammo can so I can mount one of these heat sinks to each side. I will be monitoring cell temperature in use and decide then if I need to add a fan to each heat sink. Hopefully the heat sinks will be enough by themselves.