custom made battery box for eve LF280K cells

[houseofancients]

Thank you for all the replies and advices. I torqued the BMS busbars at 7 Nm and the cells busbars at 5 Nm
I torqued the compression plate at 9 Nm and the rest manually, like houseofancients said it's less important.

I also watched the Andy's video and saw he didn't put the copper washers between the cells terminals and the busbars.

When I assembled the battery, I put them, but now I think it was maybe not a good idea, as the terminals and seplos busbars are in aluminium, what is the goal to had copper beetween ?

I also "cleaned" cells terminals with a 600 sand paper (using a technique I saw on a "Ray builds cool stuff" video) and sand the part of the aluminium busbars in contact with the copper washer.

I also added MG847 paste between cell terminal and copper washer (but not between copper washer and aluminium busbars)

Do you know why Seplos choose aluminium busbars ?

After reading lot's of threads and comments under Andy's video, I think it maybe not a good idea to keep aluminium busbars / copper washers

I still have the tinted copper busbars delivered with my Docan's cells.

What do you advice me to do for good and long lasting connections ?

1) Keep it like that (Seplos aluminium busbars + Seplos copper washers on cell terminals)
2) Replace aluminium busbar by Docan's tinted copper busbars (and keep or remove copper washers ?)
3) Other solutions ?

the purpose of the copper rings is to crush and provide a better and absolutely flat contact area between the busbar and cell terminal.
if using soft aluminium or copper busbars, and using the correct torque, the shouldnt be needed.
any bad, or less than optimal connections will generate heat , and a flir camera ( or touch) would reveal that

i think Seplos choose aluminium for the busbars because the cell terminals are aluminium , and the bms does calculate the resistance at specific points in your build...

any how, it think , reading above , you'll be just fine

 

[justgary]

Copper against aluminum is not recommended for long-term use because they are too far apart on the galvanic scale. The copper will pit the aluminum. Tinned copper is OK against aluminum.

 

[Ron-ski]

For anybody in the UK looking for a Seplos kit they are now available for pre-order from Fogstar.

SEPLOS Mason 48V 280Ah DIY Battery Kit (14.3Kwh)

The Seplos Mason Kit includes everything that you will need to create a DIY 48V 14.3Kwh battery (prismatic cells sold separately). UK Stockist. Lowest Prices in the UK. Fast Delivery.

www.fogstar.co.uk

 

[danmc]

For anybody in the UK looking for a Seplos kit they are now available for pre-order from Fogstar.

SEPLOS Mason 48V 280Ah DIY Battery Kit (14.3Kwh)

The Seplos Mason Kit includes everything that you will need to create a DIY 48V 14.3Kwh battery (prismatic cells sold separately). UK Stockist. Lowest Prices in the UK. Fast Delivery.

www.fogstar.co.uk

FFS I've just paid more than that to have one shipped from China and i'm still waiting. My cells are coming from Fogstar too. ?

Cheers for the heads up btw. ?


I notice they also sell a similar kit but a different form factor.

https://www.fogstar.co.uk/products/seplos-tall-48v-280ah-diy-kit-14-3kwh?variant=41178807173179

 

[houseofancients]

For anybody in the UK looking for a Seplos kit they are now available for pre-order from Fogstar.

SEPLOS Mason 48V 280Ah DIY Battery Kit (14.3Kwh)

The Seplos Mason Kit includes everything that you will need to create a DIY 48V 14.3Kwh battery (prismatic cells sold separately). UK Stockist. Lowest Prices in the UK. Fast Delivery.

www.fogstar.co.uk

shaw that, shame fogstar doesnt ship to continental EU

 

[SeaGal]

For anybody in the UK looking for a Seplos kit they are now available for pre-order from Fogstar.

SEPLOS Mason 48V 280Ah DIY Battery Kit (14.3Kwh)

The Seplos Mason Kit includes everything that you will need to create a DIY 48V 14.3Kwh battery (prismatic cells sold separately). UK Stockist. Lowest Prices in the UK. Fast Delivery.

www.fogstar.co.uk

Seems counter-intuitive to me that they are marketing that product when they've just launched their own battery racks. Guess this will plug-the-gap for DIYers that are buying 280Ah / 304Ah cells from them. Happy with my plywood and celotex box though... it cost much less than £499 ?‍

 

[SeaGal]

shaw that, shame fogstar doesnt ship to continental EU

Guess you meant 'continental Europe' But are you sure they don't at all? Their retail site doesn't mention it, but their wholesale site refers to providing "EORI (If shipping into EU, please provide EORI number if you have one) (optional)" - Maybe worth asking @Ben@Fogstar about it?

 

[houseofancients]

Guess you meant 'continental Europe' But are you sure they don't at all? Their retail site doesn't mention it, but their wholesale site refers to providing "EORI (If shipping into EU, please provide EORI number if you have one) (optional)" - Maybe worth asking @Ben@Fogstar about it?

i did send them a few messages on FB and email, never go a reply,
EORI is only handed out to businesses, which i am obviously not

 

[Ben@Fogstar]

We can ship to Europe, no problem. Would be on an email basis though and not via the website. They are actually due in a couple of weeks but we put an extra 30 days on the leadtime so I could have a play!

 

[SeaGal]

There you go @houseofancients + @Ben@Fogstar... SeaGal the matchmaker

 

[houseofancients]

There you go @houseofancients + @Ben@Fogstar... SeaGal the matchmaker

well, a bit to late for me now, already have more than enough cells and mason kits for the foreseeable future ...
wish this was known before though, Fogstar does seem to be on top of their game

 

[Rickster1978]

Just reviving this as I’ve got an issue with tightening the battery cell bus bars on the Seplos Mason.

I used the forum and decided to tighten the battery terminal nuts to 4nm. First one I’ve tried has snapped off so I’ve stopped and not going to try any others yet. How easy is it to replace a broken screw thread on a cell?



Now the bit that I really don’t get, and I’m sure someone may be able to explain. I tightened the end panel that compresses the batteries to 9nm. Got the click on the torque wrench so happy it’s tightened to the right level. Now when I go back to those with the wrench set on 4nm they aren’t clicking… surely they should click and not tighten even further. I would expect 9nm to be ‘tighter’ than 4nm but am I wrong?? Or is my new torque wrench faulty.

 

[SeaGal]

surely they should click and not tighten even further. I would expect 9nm to be ‘tighter’ than 4nm but am I wrong?? Or is my new torque wrench faulty.

You are correct. Your torque wrench should "click" (but read below) when set to 4Nm and you should then stop tightening.

Your wrench _may_ be faulty, but in my experience when they are set to very low torque settings you don't really hear a click at all (certainly not with my old ears!) - it's more a gentle "feel" on the handle. You have to go really careful, because if you miss it, then you overtighten and break something. Test it out again on the 9Nm bolts and see if you can feel the wrench release. HTH.

Sorry to hear about the broken screw - do a search on here, quite a few threads about what can be done.

 

[Rickster1978]

You’re absolutely right. I’ve just gone out to the garage again and I can hear the faintest click. It’s definitely user error

So I don’t think I have the tools to replace the terminal from the quick search I did on YouTube. Wondering if it’s going to be a case of ordering a new cell.

 

[SeaGal]

You don't want to have a bad / dangerous connection from a substandard repair with the amps flowing through the system, so I think if I were in your position I'd get another cell. Did you get the kit from Fogstar in the UK?

 

[Rickster1978]

Mine didn’t come from Fogstar but it was a UK distributor so I’ve contacted them to see if I can get a cell sorted.

 

[Rickster1978]

Little bit of thread left but not enough unfortunately

 

[houseofancients]

Little bit of thread left but not enough unfortunately

it broke sheer off ?
usually it rips off at the welt because it was done badly, but havent seen this before

 

[Rickster1978]

it broke sheer off ?
usually it rips off at the welt because it was done badly, but havent seen this before

Yep broke about a third of the way up. I’m currently watching videos showing repairs but I think it’s going to be easier to just grab a new cell (unless I can find a local company with all the kit needed)

 

[houseofancients]

Yep broke about a third of the way up. I’m currently watching videos showing repairs but I think it’s going to be easier to just grab a new cell (unless I can find a local company with all the kit needed)

this would be a warranty case...
not sure where you bought the cells, but the supplier should replace this one, as the stud was of inferior quality