Merged LiFeYPO4 1000Ah Winston prismatic cells and all electric galley...

[LeighC]

Originally Posted by s/v Jedi

Laminated from5 layers and the roll you describe. 34mm wide, my terminals are M14.

Thankyou Jedi,
In my opinion I think the key to all this in the large format plastic cased industrial cells is the 14 mm (9/16") terminal bolt or stud.

My CALB CA400 cells (& others) have this and are perfect.

The slotted hole is only there for 1st installation, there is not going to be much sliding done when the bolt is done up to the correct tension.

With Jedi's multiple layer bus bars you don't need slots to create a bad connection.

But is there a risk with a higher resistance between the 0.5mm (20 thou)
multiple thicknesses

Regards - Leigh

[AKA-None]

Any reason you can’t use flat flexible cables?

[newhaul]

Originally Posted by AKA-None

Any reason you can’t use flat flexible cables?

Actually none that I can think of except the actual short distance from one cell to the next. My 250ah cells that means less than 2 inches. Solid bar is fine especially with whole thing in a set compression box .

[s/v Jedi]

Here’s some more pictures

[newhaul]

Originally Posted by s/v Jedi

Here’s some more pictures

Looking really stout wish mine were as robust on my 250ah cells

[Catapault]

Originally Posted by s/v Jedi

Here’s some more pictures

Those are Winston 400AH ?

[LeighC]

Another good thing in my opinion is these high end plastic cased industrial cells have the ventilation between the cells.
Jedi's above picture (Winston's) shows it well, with the ridges butting together & leaving a vertical air passage.
My CALB CA400 Grey cells have this also (although not as good as the Winston's) & spent their first 5 years with summer temps in the high 40°C (nearly 120°F) on some days. (Outback Australia) probably not as critical in a cooled hull in water though with consistent temps.
The smooth sided cheaper aluminum cased ones really need a slotted spacer to allow this breathing in my opinion.

[goboatingnow]

Originally Posted by LeighC

Another good thing in my opinion is these high end plastic cased industrial cells have the ventilation between the cells.

Jedi's above picture (Winston's) shows it well, with the ridges butting together & leaving a vertical air passage.

My CALB CA400 Grey cells have this also (although not as good as the Winston's) & spent their first 5 years with summer temps in the high 40°C (nearly 120°F) on some days. (Outback Australia) probably not as critical in a cooled hull in water though with consistent temps.

The smooth sided cheaper aluminum cased ones really need a slotted spacer to allow this breathing in my opinion.

Yes I was looking at using aluminium heat sink extrusions , and optional forced air, plastic casing seems to be on the way out.

[LeighC]

Originally Posted by goboatingnow

Yes I was looking at using aluminum heat sink extrusions , and optional forced air, plastic casing seems to be on the way out.

I hope the Winston's, GBS, CALBS, Sinopoly's etc. stick around, they take up a bit more room though.
The expensive Victron battery packs look like they have Winston's inside.
The ventilation IMO is needed with high charge rates more so & we are talking about cycle life over many years here.
It seems to be a real problem with EV's & the cooling systems are advancing at a fast pace.

[s/v Jedi]

Originally Posted by Catapault

Those are Winston 400AH ?

Yes they are. We love them, changed life aboard completely.

[Simi 60]

Originally Posted by LeighC

Another good thing in my opinion is these high end plastic cased industrial cells have the ventilation between the cells.
Jedi's above picture (Winston's) shows it well, with the ridges butting together & leaving a vertical air passage.
My CALB CA400 Grey cells have this also (although not as good as the Winston's) & spent their first 5 years with summer temps in the high 40°C (nearly 120°F) on some days. (Outback Australia) probably not as critical in a cooled hull in water though with consistent temps.
The smooth sided cheaper aluminum cased ones really need a slotted spacer to allow this breathing in my opinion.

Looking at my smooth sided cheaper aluminium cased batteries now

Just to give you a reference point.....
Now @ 6:20 am, has them at 22.7c (72.8f) which is ambient temp in the room they are stored aft of ER
In peak summer after full day of motoring rarely if ever saw them above 35c (95f) which, was the ambient temp at that time.

Dividers in our case are 1.5mm plastic cutting boards

[PaulCrawhorn]

There should be nearly no internally generated heat detectable from the outer case in a House bank designed for longevity.

A separate bank should be used if high C-rates are desired.

[Catapault]

Originally Posted by s/v Jedi

Yes they are. We love them, changed life aboard completely.

Cool, 4 of exactly those is what I just ordered, along with the straps. With a view to add 4, possibly 8 more of the same cells as finances allow next year.

After much searching, found someone with a REC BMS in stock, and both it and batteries should show up by end of the week.

Let the fun commence !.

[newhaul]

Originally Posted by Catapault

Cool, 4 of exactly those is what I just ordered, along with the straps. With a view to add 4, possibly 8 more of the same cells as finances allow next year.

After much searching, found someone with a REC BMS in stock, and both it and batteries should show up by end of the week.

Let the fun commence !.

Don't forget build photos . enquiring minds want to see.

[aybabtme]

Alright I know just a few weeks ago I was lambasting the unecessity of using raw cells in our modern times with the abundance of high quality and cheap commercial packs. But alas, reality struck me and the odd shape of the locker where I can store the batteries is forcing me down the path of a custom pack made with raw cells.

* * *

Here's the requirement brief:

• 35ft lightweight catamaran (Seawind 1000 XL2)
• Rated for max 2x10kW engines, so design for 20kW continuous discharge (although will be less than that in reality).
• Aim for 1h range at full power (20kWh).
• Obviously 48V nominal for this power requirement. I don't want to go higher than 60V.
• Price is a lesser concern, since it's overall not a big differentiator in the overall project.
• Delivery to California (SF or LA).
• Available volume is two compartments of dimensions 890mm (length) 250mm (width) 41mm (height).
• Weight is a concern, so aluminum encased cells it is.

Right now the contenders are:

• CATL 302Ah in 2P16S: 185Wh/kg, 167kg, 30.9kWh
• CALB L173F230B in 2P16S: 175Wh/kg, 134.4kg, 23.6kWh
• Fortune 205Ah in 2P16S: 156Wh/kg, 134.4kg, 20.9kWh

The Fortune could seem a clear loser here, but they gain extra point in my book for being so easy to assemble and work with.

Here's my notes so far (see "Mothership: LFP cells"). The BMS is a Rec Q 16S. Busbars and distribution is Victron's Lynx setup with Cerbo GX and Multiplus II for main charge source.

Actual engines will probably be ePropulsion Navy 6.0, although their long shaft variant is a bit too short. Current engines are gas Yamaha 9.9 outboards with extra-long shafts (25"). I'll figure out some story for "range extension" later. We have gasoline tanks onboard so the easy way is to used Honda EU2200... but I don't like the smell of gasoline. And yes, it's unclear whether this is all a good idea or not, but I want to try it out so
* * *

I guess there should be a question: do you know of any cell I should evaluate here that's not in my spreadsheet?