PINNED - Lithium battery conversion/info

[terry2]

Glad to hear you finally got them - yes i used the same Tape to wrap each cell - i also used silicone sheet between each cell that would be touching - mines was an ADD ON - i have foam around the edges and in plastic box - on a full pack - i would use the silicone around the whole pack also sides front back etc, or something plastic after the tape of each cell also

this was my first in chair pack going on 4 summers now - its not the best wrapped - these are headways so they dont touch each other - and sit in a plastic tray - i havnt looked at it in years now just use and charge -

"silicone sheet " I will look for it now.
What kind of sheet and have you a link to it? I'm finding it hard to find any on amazon
Thanks dude.

Edit= https://www.ebay.co.uk/itm/SILICONE-RUB ... Rj3qa7UnnQ

Is that it?

[terry2]

Terry, I am really encouraged that your cells seem to be in good shape.

Mine clearly were not. The bulging was obvious, as were signs of prior use (though I tried to talk myself out of that notion early on).

I charged the first of my cells with the 30 amps setting in BM's script. That took a bit over 5 hours. 30 amps made some wires too hot for my liking, so I backed off the charge rate to 25 amps. At 25 amps, it took close to 8 hours to charge each cell.

Like BM said, my cells seemed to arrive pretty empty (though I think they had more like 10% to 15% rather than 1% charge).

I have an email into lifepo4-batteries with pictures of the issues with my cells and am hoping we will be able to work this out amicably.

Steve

Lets us know how you get on.
I would think they will send you a replacement. But tell them to pay the shipping fee.

[Burgerman]

Like BM said, my cells seemed to arrive pretty empty (though I think they had more like 10% to 15% rather than 1% charge)

Nope. They were discharged basically fully. The discharge line from 2.9V to 2.5V is almost a straight line. About 2Ah. So obviouly just been tested and not recharged. Or removed from something that had discharged down to the BMS lower limit.

[expresso]

Glad to hear you finally got them - yes i used the same Tape to wrap each cell - i also used silicone sheet between each cell that would be touching - mines was an ADD ON - i have foam around the edges and in plastic box - on a full pack - i would use the silicone around the whole pack also sides front back etc, or something plastic after the tape of each cell also

this was my first in chair pack going on 4 summers now - its not the best wrapped - these are headways so they dont touch each other - and sit in a plastic tray - i havnt looked at it in years now just use and charge -

"silicone sheet " I will look for it now.
What kind of sheet and have you a link to it? I'm finding it hard to find any on amazon
Thanks dude.

Edit= https://www.ebay.co.uk/itm/SILICONE-RUB ... Rj3qa7UnnQ

Is that it?

yeah you can use those also - i have found some on Amazon - i cant find my own order now - but i used 1mm on the 60ah Cells - but used .05mm on the 80ah cells - both worked fine to me and if space is tight even .05mm was fine - if you have space and feel better using 1mm thick - use that - between the tape wrapped cell and 1mm - your good


https://smile.amazon.com/s?k=silicone+s ... _sb_noss_1

[swalker]

Instead of tape, I am using shrink wrap PVC

https://www.amazon.com/gp/product/B07FX ... UTF8&psc=1

I will put in a layer of 0.10 inch fish paper (electrical insulation paper) before applying the shrink wrap.

If I am not able to get the bulged cells replaced, I plan to put in 5 to 10mm foam of some sort between the shrink wrapped cells (because they are so bulged).

Steve

[shirley_hkg]

Working on a 1P7S 70Ah power bank, I begin to love this self-adhesive "fish paper"
very much .

[shirley_hkg]

Hi Shirley, once I've cut mine into studs and am ready to assemble. I'm going to drop them into a cup of white vinegar with a dash of bicarbonate of soda. Apparently it's really good at removing any surface oxidation and makes the copper really shiny new

Interested to see the result .

I sent you my own set . Stupid me that I didn't leave myself a bit for trial.

[Burgerman]

What is fish paper?

[Burgerman]

I wouldnt use copper. Once you clean all that oxide off, and watch for an hour it goes dull again. Why? It oxydises fast. Oxides dont conduct at low voltages well... And thats why the ones you buy are plated in zinc cadmium etc. But nobody listens! Its why I use that tinned marine cable, tinned ring terminals. Tinned anderson connectors, etc etc. Copper conducts great. Its a bad contact surface.

[shirley_hkg]

What is fish paper?

I use the 1mm thick ones .

[expresso]

I wouldnt use copper. Once you clean all that oxide off, and watch for an hour it goes dull again. Why? It oxydises fast. Oxides dont conduct at low voltages well... And thats why the ones you buy are plated in zinc cadmium etc. But nobody listens! Its why I use that tinned marine cable, tinned ring terminals. Tinned anderson connectors, etc etc. Copper conducts great. Its a bad contact surface.

i listen - because i see my contacts also - which i used copper on my ring terminals at first - you can see how they become - the wiring on my first full pack - i used copper rings - i am not worried because it works fine - BUT if i had to remove the pack or i see its not showing up good in the graphs etc, - i would redo the wiring with tinned copper terminals -

i found good ones - thick walled for crimping and deeper - i like them much better -

[Burgerman]

Fish?
Do you mean gasket paper?

What is it made of? Dont say fish...

[expresso]

[Burgerman]

I made myself hungry now. Smoked mackerel in the fridge! And I am in bed. And no way to get it.

[shirley_hkg]

Fish?
Do you mean gasket paper?

What is it made of? Dont say fish...

viewtopic.php?f=2&t=1813&p=133204&hilit=Fish+paper#p133204

Um *,gasket paper .

[shirley_hkg]

I made myself hungry now. Smoked mackerel in the fridge! And I am in bed. And no way to get it.

We need a robot somehow .

[Burgerman]

Mine went off and married some other guy.

To be fair she would rather have married me but what can I say. I am an idiot!

[terry2]

I wouldnt bother. The used ones did well. So those will be better still. Take say 20Ah out of each one since they shouldnt be stored full. Then assemble the pack.

To do that, connect, choose discharge, and watch the mah counter on screen. when it hits 20,000mAh or 40,000mAh press stop. Make sure you do each the same give or take a tin=y bit. Or it will take an age to balance after you assemble the pack.

So now you need to figure out how its going to be separated, as each case is "live". If they can ever touch you will get fireworks.
Others will tell you how they do it. Dont forget the bottom. Or sides.

Morning all.

BM I am on the cells tab. I press start..then chose the Discharge icon.

But I don't see "when it hits 20,000mAh or 40,000mAh press stop"

[Scooterman]

Interested to see the result .

I sent you my own set . Stupid me that I didn't leave myself a bit for trial.

Aw Shirley, I feel bad now!
Thank you you're good to me
I will keep you updated as to how I get on

I'm really looking forward to getting the new PS. I've placed a smoke alarm on the bench where my 24v PS cooling fans exhaust. Just in case it goes up in flames when I'm in bed!

I thought I'd test the capacity of each cell just for the hell of it while I'm waiting for your bits to arrive . My PS can't handle anymore than one at a time. The first two are very close, I'm on no.3 now. When discharged I put about 30% back in +/- and few mAh.
Am I wasting my time testing each cell? I'm writing the mAh rating and date tested on each cell.

[terry2]

Interested to see the result .

I sent you my own set . Stupid me that I didn't leave myself a bit for trial.

Aw Shirley, I feel bad now!
Thank you you're good to me
I will keep you updated as to how I get on

I'm really looking forward to getting the new PS. I've placed a smoke alarm on the bench where my 24v PS cooling fans exhaust. Just in case it goes up in flames when I'm in bed!

367F2E68-A55C-4EF5-82D5-257288DB19F2.jpeg

I thought I'd test the capacity of each cell just for the hell of it while I'm waiting for your bits to arrive . My PS can't handle anymore than one at a time. The first two are very close, I'm on no.3 now. When discharged I put about 30% back in +/- and few mAh.
Am I wasting my time testing each cell? I'm writing the mAh rating and date tested on each cell.

What option in the software did you tick to show your mAH?

Thanks

[Scooterman]

I made myself hungry now. Smoked mackerel in the fridge! And I am in bed. And no way to get it.

Smoked mackerel is my absolute favourite, I always have it in fridge. With or without peppercorns. Years ago it was really cheap, not so much now.

[Scooterman]

What option in the software did you tick to show your mAH?

Thanks

Click on CELLS tab and look in bottom LH corner. Shows cap IN/OUT in mAh.

[terry2]

What option in the software did you tick to show your mAH?

Thanks

Click on CELLS tab and look in bottom LH corner. Shows cap IN/OUT in mAh.

That's what I thought.
If you look at my picture above when I was discharging. It does not look the same.
My mAH is a very small number

[Scooterman]

Well it won't be you were only discharging at 4A for 50secs!

btw anyone thought of wrapping a job lot of self amalgamating tape round each cell?

Or dipping each cell in a can of plasti-dip?

Or giant heat shrink? Yes you can get it in huge diameters.

[terry2]

Well it won't be you were only discharging at 4A for 50secs!

Silly me.

So discharge it longer to get the real mAh showing?

BM told me this

"To do that, connect, choose discharge, and watch the mah counter on screen. when it hits 20,000mAh or 40,000mAh press stop"

I have just tried 4 mins discharge. The Cap. OUT says 458 mAh.
This is very confusing to me.....I am just scared I will muck up a cell

[terry2]

Is this right?

In the Cells tab it says now I am discharging Cap. OUT = 1470 mAh

I wait till that counter goes up to 20,000 mAh....

[Burgerman]

Yes.
1470 mAh is 1.47Ah.

So to remove 20Ah means taking that 20,000mAh out. How many Amps is it discharging at? 10? Then it will take 2 hours.

[terry2]

Yes.
1470 mAh is 1.47Ah.

So to remove 20Ah means taking that 20,000mAh out. How many Amps is it discharging at? 10? Then it will take 2 hours.

So stop it when it reads 20000 as I haven't got the " . " to make it read 20,000

Thanks again.
Thought I mucked it all up.

[Burgerman]

Its a huge 176Ah battery. Actually a cell.

Thats 176 000 mAh. The reason it reads mAh instead of Ah is because its designed for hobby batteries. And thats how they are measured or rated. But its the same thing.

Just ignore the last 3 digits and its Ah.

You are taking 20Ah out of a 176Ah cell. Thats just enough so that they dont feel all stressed out. Lithium doesent like being sat full for long periods and we dont know how long you will take to get the pack built.

[terry2]

Its a huge 176Ah battery. Actually a cell.

Thats 176 000 mAh. The reason it reads mAh instead of Ah is because its designed for hobby batteries. And thats how they are measured or rated. But its the same thing.

Just ignore the last 3 digits and its Ah.

You are taking 20Ah out of a 176Ah cell. Thats just enough so that they dont feel all stressed out. Lithium doesent like being sat full for long periods and we dont know how long you will take to get the pack built.

I got it now( I hope)