EIG C20 cells (UK)

[doobedoobedo]

I've just got back from picking up some of these cells. http://www.ebaracus.com/sites/default/f ... asheet.pdf

The company I got them from has a surplus of unused, boxed cells, approximately 50,000.

How they came to me, two of these to a box:

I checked the voltage on the cells in the one I opened - all 3.74 or 3.75 V per cell.

If any one is interested PM me and I'll give you the guy who's dealing with them's email address.

NB. I have nothing to do with the company, just passing on something that others may find useful.

[langoo]

Do you mind sharing the price per cell? I guess buying more gets you a better price but just for some guideline of the price-level would be interesting.

[doobedoobedo]

I'm afraid I said I wouldn't share what I paid. But they want rid of them, and I feel I got an incredibly good deal.

Best thing you can do is have a chat with the guy dealing with it at their end, he was very open to negotiation.

[zippy500]

they look interesting , do they have the coupling plates for the cells.

how many cells did you get, would need a good few to make a 360v pack

Is my maths correct that you would need 300 cells to make a 22Kw pack ?

[doobedoobedo]

I got 500 for a 36kWh 100S5P pack. They did still have some bus bars for joining the cells into packs, but it's a case of once they're gone they're gone I think. I took the last joining plate for the bottom of the packs and will have to get some more made up from it. They were making 10S5P modules for their project cars (I have a couple of photos of the modules in my project thread).

[arber333]

I got 500 for a 36kWh 100S5P pack. They did still have some bus bars for joining the cells into packs, but it's a case of once they're gone they're gone I think. I took the last joining plate for the bottom of the packs and will have to get some more made up from it. They were making 10S5P modules for their project cars (I have a couple of photos of the modules in my project thread).

Can you make some closeups of your bus arrangement so we can see how the cells are connected?
I mean are those threaded M5 holes or just normal 6mm bore etc...
tnx

[doobedoobedo]

Sure, I'm probably going to build up a pack tomorrow now I have my motor spinning.
They gave me the busbars and fasteners which I'm pretty sure are M3, I can reverse engineer the bus bars and put up CAD drawings if you need them, I need to get some for the ends anyway.

[doobedoobedo]

OK, didn't make up the pack, but took some more pictures of the hardware they gave me.

This was the last one of the bottom cell joiners they had, I need to get 9 more cut, happy to put up drawings once I've got all the measurements, all holes are low clearance for the M3 tapped holes in the bottom of each cell.

The top of the cells, there is a channel either side at the top for 6mm rods to help compress the cells. Each contact has two connectors tapped M3.

With one of their bus bars, I'll need to get the +ve/-ve ends cut myself. Again I'll put up drawings once I've got full measurements if people are interested.

And with one of the BMS PCBs they threw in with mine.

[jnsaff]

Just letting you all know that they need to get rid of their remaining ~40k cells in the next few weeks and are very open for negotiation.

I’m getting 1 or 2 thousand cells. My transport will also pass through NL, BEL, Ger, Poland and Baltics should anyone be on the way and need transport.

[doobedoobedo]

Yup just got an email saying they were looking to wind things up at their Leamington Spa facility in the next 2-3 weeks and they still have approximately 40k cells left.

[johu]

Is that still up? I'd be interested in 20kWh.
Is the transport option still available?

[jimbob01]

Hi Johannes yes I have plenty left feel free to message or call me I've sent you a pm
regards James

[jimbob01]

Transport available to some of the EU.

[Stephen Darbey]

Hi There

Dealt with this guy ( James ) recently and purchased some EIG Cells. No issue dealing with at all. If this was an EBAY purchase I would have to give excellent feedback.

Regards
Stephen

[jimbob01]

I still have a few thousand of these cells left at £10 a cell on singles and £9 a cell on boxes of 50.regards James

[jnsaff]

Does anyone have the bus bar drawings for these cells still? I'd be interested in 5p, 7p, 10p or such. Thank you!

[doobedoobedo]

I've attached a FreeCAD file of the bus bars I have (supplied with the cells, so they're the ones the manufacturer was using). Reverse engineered with calipers to the best of my ability. The centre hole is tapped M4 for BMS attachment. They're 3mm aluminium. The cells have to be quite heavily compressed for them to fit.

[jnsaff]

Thank you.

So the terminal connectors on the cell side are not Copper then and are safe to put together with Aluminium?

Also do you feel the heavy compression could be an issue?

[doobedoobedo]

The contacts on the cells are copper coloured - so probably copper. Do you think the Cu/Al interface will be a problem?

As for the compression - No I don't think this would be a problem, in fact it's a good thing. Cells like to be compressed in high current situations. I mentioned it because the bus bars have no chance of fitting without compression.

[jnsaff]

Cu/Al in a standard electrical installation (AC tho) is a big no-no and needs to be handled with special connectors. In essence after a while Al side will turn into dust and can cause arcing and poor connectivity (high resistance == heat == fire).

[doobedoobedo]

Thanks for the heads up! Not too keen on fire... copper has much better conductivity too.

[jnsaff]

Zinc is usually used in the 18650 world but not sure it would be economical in our application. Also the connectors on our cells may be some alloy that is safe with Al. Needs to look into it a bit more.

[doobedoobedo]

As I think I said, my bus bars were supplied along with the cells. They had a couple of completed packs using the ally bus bars too. But they were prototypes so not necessarily built with longevity in mind...

[SciroccoEV]

Thanks for the heads up! Not too keen on fire... copper has much better conductivity too.

Aluminium has lower resistance than Copper for a given weight of material, which is why it's used for grid transmission lines and is gaining popularity in OEM EVs.

It is tricky to make reliable connection with. It can be co-extruded with Copper, or plated. Ultrasonic, friction and electron beam welding are also used.

[jimbob01]

Isn't there a paste that can be used on dissimilar connection applications...alunox or something like that... Cedric lynch was recommending one ..I will find out....