200Ah Pack

[Scooterman]

You're table is useful espresso. 9 Awg should fit snug in 6mm lug

[expresso]

I am a bit confused if I remove the buss bars. And solder a thin wire I don't get how I would solder it and then screw down a nut over it? I could use. Visual on that. Also the blue lines that Shirley shows don't get it. I am not too swift need more hand holding

[expresso]

I have smaller rings. Could use 12 awg wire but need a new crimper these r u insulated. Or I can try insulated I have but can't solder them they have glue for heatshrink. Wonder if that's good instead of the buss bars

[expresso]

i rearranged the wire to connect them both - the first pic with the red cable was just to test it - no intentions to leave it looping outside the pack

[expresso]

Ok i redone the wires and its much better now - i crimped them and soldered them - using 12 awg wire - they fit just right


i am going to use the cables - tomorrow will connect it and lock them down - then start to charge and discharge over the weekend

will save the buss bars - maybe have them tinned if it dosnt cost too much just in case - have a back up - but i think the cables i made will be just fine.

[Burgerman]

Thats better. Also better to put the smaller terminal and wire in the top. And to use nyloc nuts. Then its as good as it can be.

As you use the chair, half the power comes down the thinner wires, and the other half joins it, and goes down the bigger wire. So all good.

Nyloc, and a tiny smear of grease only on the top of the thread before you add the nut. Then if a wire is banged, or knocked the nut stays tight, and only the ring terminal turns, keeping tension. And they dont need be over tight to stop them coming loose.

https://en.wikipedia.org/wiki/Nyloc_nut

[Scooterman]

Why the grease?

Eager to learn

Does also apply to M6 studs or only necessary on M4?

[Burgerman]

On all stainless. Because it galls, or welds itself or grabs, to similar clean dry stainless steel, like the stud... Suddenly and it can really jam solid! Stainless doesent run well against more stainless without lubrication. And grease stays.

With a touch of grease it will run freely and behave as it should even when you want to undo it. Without seizing and unscrewing the stud from the battery. And because the nylon part of the nyloc nut is very tight, so it too may unscrew the stud when undone later. So a touch of grease!

[Burgerman]

Here ya go: https://www.kayfast.co.uk/information/T ... -Fasteners

Or https://www.essentracomponents.com/en-g ... teel-bolts

I built a lot of stuff, and broke everything possible many times over. Thats how I learn! The link above makes a drama out of it.
A tiny dab of grease means you wont ever get the problem. You should always grease or oil all threads (or loctite them), anyway!

Its dry clean clean stainless steel thats the problem. Seldom or never happens with normal steel. Unless bare steel. But steel bolts are zinc, cadmium, or nickel plated. Or otherwise coated and that prevents it too.

[shirley_hkg]

I like this SS M4 flange lock nut.

Large contact ,
Plain base,
Thick means more threads .

Will grease it for perfection .

[Burgerman]

With a wide base, if you tug a cable anti clockwise it will loosen the nut rather than sliding around under it, and remaining tight. But as long as that doesent happen...

Personally I would use a plain, stainless, nyloc nut! And stainless loctited in place stud.

[Scooterman]

Here ya go: https://www.kayfast.co.uk/information/T ... -Fasteners

Or https://www.essentracomponents.com/en-g ... teel-bolts

I built a lot of stuff, and broke everything possible many times over. Thats how I learn! The link above makes a drama out of it.
A tiny dab of grease means you wont ever get the problem. You should always grease or oil all threads (or loctite them), anyway!

Its dry clean clean stainless steel thats the problem. Seldom or never happens with normal steel. Unless bare steel. But steel bolts are zinc, cadmium, or nickel plated. Or otherwise coated and that prevents it too.

Thanks mate, I didn't know that

I think I've actually noticed that but never worked out why? On occasions it's been as if I've crossed threaded a nut/bolt but knew I hadn't. But could never work out why it was binding. It's happened both ways. Doing up and undoing. And you have to be pretty ham-fisted to cross threads with standard threads. With fine threads it's probably easier.

I like this SS M4 flange lock nut.

Large contact ,
Plain base,
Thick means more threads .

Will grease it for perfection .

I think you can get flange nuts where the flange is loose to spin. Also you can get ones with serrated flanges but that would exacerbate the possible problem BM is outlining.


EDIT: BM is a copper grease worth investing in for general assembly? I've heard good things about it but have never used it. I remember a few days ago you mentioning it, but can't quite remember what it's application is for?

[Burgerman]

Yes but not on batteries.

But for our purposes plain lithium grease is good enough.

[Scooterman]

Without seizing and unscrewing the stud from the battery.

I notice when I looked extremely closely at the copper studs I extracted that on some there was a faint trace of aluminium powder. Nothing to worry about, but the silver colour is a good contrast to the copper colour. I think regardless of what material the studs/bolts are made of, repeated tightening and untightening in and out of aluminium threaded holes should be avoided. Aluminium isn't a good material for a thread.

Without wishing to bang on about my manual wheelchair again today, it's relevant. In that it's chunky adjustable brackets are some sort of aluminium alloy. When I got the chair and had to tweak the settings, I noticed that the HT steel bolts were so tight in the aluminium. The allen key flexed before the bolt cracked loosed. When I re-postioned the set up and re-installed the bolts I greased each one. They should have done that in the factory.

[Burgerman]

Manufacturers dont care. I used to buy brand new bikes, 10k a pop, and strip and rebuild with grease... At least most of it. And replace many fasteners with better. The japanese are no different. They are in a hurry to get it out of the door fast and as cheap as possible. So connectors need petroleum jelly, steel self tappers are replaced with stainless. Visible bolts are replaced with better etc. Things like taper roller head and swing arm bearings, reassembled WITH some grease... Etc.

The same basic initial setup that you should do with a powerchair the days after it arrives. If you dont, nobody else will.

[expresso]

Using 12 awg wire makes the job alot neater - fits just right with the larger wire going across. i have test fitted a 10 awg and it didnt fit as flush or as neat - this wire is cut to 3 inches - very short wire - should handle its purpose. i have nylon lock nuts - the ones in the pictures above were just for testing -

i also have lithium white grease -

BM - where do i add a small amount of this grease ? on the stud sticking up at the very top only - then screw down the nut over it and tighten ? would this affect the locknut as it gets grease on it also ?

i plan to put it all together tonight and then can start to test it - charge discharge etc, - if all goes well - i plan to also take those buss bars and try to get them treated in Zinc ? or what would be best - can save them as a back up just in case -

thanks for all the suggestions from everyone so far -

[Burgerman]

Just the top where the nut goes.

Also you dont have nylon locknuts. You have Nyloc nuts. See: https://en.wikipedia.org/wiki/Nyloc_nut

You may confuse people. Because nylon locknuts means using two nuts, made of nylon locked against each other.

[flagman1776]

Nylock nuts are sometimes call aircraft nuts, because of their internal nylon locking feature.

[expresso]

i have the first nut you posted - the top one is the one i have to use

about the grease - you mean just add a touch on the stud thats on the Cell - ?

[Burgerman]

Yes, just a smear on the top bit where the nut goes.

I know which ones you have, but you keep calling them nylon nuts, and it will confuse people reading this later that dont realise you mean Nyloc.

[expresso]

Yes, just a smear on the top bit where the nut goes.

I know which ones you have, but you keep calling them nylon nuts, and it will confuse people reading this later that dont realise you mean Nyloc.

i see - got it -

[Burgerman]

I have a young girl, for e.g by email with a bounder, following this thread. She is about 13. Bright, claims to be a tomboy and is about to learn to solder (her dad will show her)and wants to fit lithium. She just made a still! Her dad will help but isnt technical. She will take things here very literally. She is going to copy you, and build a pack for her bounder as soon as her chair gets here. I am hoping to get her to sign up here, so she can ask questions and join in. She has a 11.5mph bounder. And a grp27 box/battery. On the way.Shese not very heavy. So for lithium I suspect a grp24 box would be better.

Question for bounder owners"
a) Will the grp24 box just fit, as in straight swap?
b) And will 16 of the 105Ah cells fit into that for certain? Cant tell her what to buy unless I know for sure.

So I can relay the info by email (at the moment...)

[expresso]

thats great - she is going to love the speed thats for sure i believe my bounder which has the lithium already in there - is a grp. 24 size box - mines dosnt stick out the back too far at all - i believe the grp 27 box sticks out a bit more - i never seen one so cant be sure -

the pack i am making now - fits in a grp24 MK Gels - - but with the bounder - its tricky - i guess would have to measure inside the box - i can try later to open mines and see what i get - you can even call bounder and ask the internal size - they may be able to help also -

i wont be able to do this till later this evening - tonight

[expresso]

i just called bounder to ask them - this is what i was told - first off - the grp 24 box and grp 27 box is the same in length but the width is a bit wider - if the chair has suspension in the rear like i do - they would fit a grp 24 box - or the chair would be much wider - on a smaller chair - they may even fit grp22 box for smaller chairs and narrow chair

i wonder if she will have a grp 27 box for real or could be a mistake ? if this is correct and its only the width that is different between the boxes - it shouldnt be an issue - more room better for packing i would think - my chair with the lithium is a grp 24 box -

[Burgerman]

No she is sure. Wanted range... So what does that mean?

I just asked if she is sure.

[expresso]

according to bounder - the battery box wont stick out past the rear anti tippers - will be a bit wider - the chair she is getting may not have indepentant rear suspension or it maybe a bit wider if it does - i am thinking her being young - they have smaller chair - and narrow models - which take smaller battery also

but if she is sure she is getting the grp 27 box - - dont need to do anything - no benefit to change it - just make it fit in the box - - may have room to cushion the pack once installed - you know he never told me if its a direct swap - but it would cost to do either way - spend the money on the Cells instead

it may be best if she waits to get the chair and then measure her box to be sure - i have a grp 24 - and i dont think i would get those 105ah cells in there 16 of them - its very very close if it does and there is no wiggle room in the box - it either fits in there or it dosnt - best to measure her box inside

[expresso]

Ok all done - this is about the best i can do with this pack - total height up the very tip of the rubber caps is 9 inchs - thats half inch lower than a MK 24 Gel i have here -

i will start to charge it up maybe tomorrow - and cross my fingers - -

[Scooterman]

The plastic nut covers are a good idea expresso. Especially for someone who’s a butter fingers with a spanner (like me )

[snaker]

Nice build, expresso

If both 12awg + 7awg ends could go into a single barrel, it might be more compact?

A terminal with 2 barrels, does it exist on Earth

[shirley_hkg]

Not likely , but M6 terminal can take wires as much as 25m㎡.

I always put more than one set of wires into a SB50.