PINNED - Lithium battery conversion/info

[Burgerman]

https://scriptasylum.com/rc_speed/lipo.html

Play with every option for 20 mins...

[foghornleghorn]

My charge cable has nine wires, its the proper cable that plugs into pl8. Do i use the red and black wires and lesve one of the white ones. I have tried to look at your pictures bm and i see u are using the red and black

Are you charging using just the 9 balance wires - with no +- bananas?

[ICEUK]

I will have positive and negative banana plug going to pl8

[stevelawiw]

3hrs Monitor graph

!0ah Discharge

Charge

[stevelawiw]

Burgerman, have you posted instructions on how to combine PL8, turnigy and a Dump load device to best effect? I was going to do a capacity check as the dump load has just arrived

[Burgerman]

Not yet.

But its kind of self explanitory.

Theres actually a bunch of ways.

Simplest is to just let the PL8 do the whole thing automatically. And thats what you should do. 2 days...

2nd is to discharge just with the dump, and connect via the turnigy thing to watch Ah. And use the PL8 as a cell monitor. But YOU must stop the discharge by unplugging the dump load when a low cell reaches 2.8 to 3 volts. And that happens fairly suddenly. Maybe over 5 mins.
3rd is to balance the PL8 input voltage with the bump connected so that the charger can discharge at 40A into the dump... Thats harder to manage and takes a little practice.

[Burgerman]

download/file.php?id=13118&mode=view
One or both white cells have high self discharge. One or both the green cells have low self discharge. Swap one from each...

download/file.php?id=13120&mode=view
The orange cell apears to have a high esistance connection to its partner, or on the charge cable or connector?

[stevelawiw]

I did the second method, the dump elements glowed bright red for long enough to get a couple of ah out of the batteries and then they touched, glowed white and melted
I've asked the seller if he sells spare coils so I can mend it myself. I think there's a need for some sort of structure to hold the coils though if they get that hot. I should have waited till the 24v fan arrives!

The orange cell apears to have a high esistance connection to its partner, or on the charge cable or connector?

I've checked the connections on that cell twice now, I can't see anything wrong

[stevelawiw]

Simplest is to just let the PL8 do the whole thing automatically. And thats what you should do. 2 days..

Why will the PL8 only dump 3.xah when it's been set to dump 10ah?

[Irving]

Simplest is to just let the PL8 do the whole thing automatically. And thats what you should do. 2 days..

Why will the PL8 only dump 3.xah when it's been set to dump 10ah?

Cos its max 100W on the internal heatsink...

You have to change settings for it to dump externally - something about power source = battery & regen capable.

[snaker]

@stevelawiw: through your graphs, it seems there is still slight issue with your balance wires. Were all terminals on balance wires perfectly soldered? Can you take a close pic of a soldered terminal?

[shirley_hkg]

That dose show sign of high resistant therein.

I'd also check if battery terminals blemished , eg. by Loctite.

[stevelawiw]

through your graphs, it seems there is still slight issue with your balance wires. Were all terminals on balance wires perfectly soldered? Can you take a close pic of a soldered terminal?

They're all done like this

And all covered in shrink wrap now, but I'm going to have another look at cell 8 (the orange one) later

[ICEUK]

Stevd, i still have no idea about where the balance wires go lol but i will get a image of how i done my connections. I have separate terminals

[sacharlie]

https://scriptasylum.com/rc_speed/lipo.html

Play with every option for 20 mins...

That is the best show%tell of all time. BMs instructions put intp pictures. The cat's meow!

[Burgerman]

Shame it doesent do 8s too.

[terry2]

Need some advice please.

I charged my cells to full and then took out 10 Amps to test my cells.
It's been 2 months since then and my cells are still separate in storage.

Now since I won't be able to install them in my new chair, because of the virus.
What is the best way to look after them?

Charge each of them back up and discharge 10-20 Amps?

Thanks in advance.

[Burgerman]

If you are interested in the best self discharge figures, and you have removed 10Ah from each reasonably accurately, then just leave them. If you need to wait another month or even 2 then it will just be a more accurate test. When you finally top up and write the Ah or rather mah returned.

If you are bored, then charge now, make an note on each as mah returned. Then discharge to around 40 to 70 percent charged. So if 100Ah cells, take out 40. To 50Ah.

[terry2]

If you are interested in the best self discharge figures, and you have removed 10Ah from each reasonably accurately, then just leave them. If you need to wait another month or even 2 then it will just be a more accurate test. When you finally top up and write the Ah or rather mah returned.

If you are bored, then charge now, make an note on each as mah returned. Then discharge to around 40 to 70 percent charged. So if 100Ah cells, take out 40. To 50Ah.

Thanks again BM.

I was worried I may wreck my cells.
As soon as this virus is over, I will have someone come and take out the heavy batteries for me.

[Burgerman]

Well if you plan on long storage, its better to take out around half. Removing 10Ah is OK. But the cells like to be stored around 40 to 70% charged for longer term store.
But first you must find the amount they have self discharged after your 2 months.

[terry2]

I have done 6 cells so far.

I took out 10 AH nearly 3 months ago.
The same 10 AH was put back in. So I think they are ok.

Just discharging them now.

[Burgerman]

We were looking for differences of say 30 or 75mah not whole Ah!

[terry2]

We were looking for differences of say 30 or 75mah not whole Ah!

Never knew I was looking for the mAh

Just looking at the saved file. They are between 10.040-10.065
Just going to do the last 2 now. Then box them up till we can go out again.

[Burgerman]

Do yo have 16? That you took the SAME 10.000Ah from? It must be accurate.

If so make pairs, that add up to the same or close amounts. So each group of 2 is the same as the other groups. Then you should avoid expressos storage problem.

A few mA matters thats what we waited for. If a cell is say 300mAh different to the rest then it will take 20 mins to balance after a months storage. Or after 6 months it will take 2 hours extra... If the difference is bigger, then it takes an extra 5 or 6 hours like expressos.

[terry2]

Do yo have 16?

If so make pairs, that add up to the same or close amounts. So each group of 2 is the same as the other groups. Then you should avoid expressos storage problem.

No.
I have 8 170 AH cells.

I will pair them as I have written on the cells after charging.

What was expressos storage problem?

[Burgerman]

You cant pair anythng with 8 cells...

He has started a new book on a seperate thread!

[terry2]

You cant pair anythng with 8 cells...

He has started a new book on a seperate thread!

So i'm good to go

[stevelawiw]

I did a full discharge/charge of my 2p8s pack I thought I'd share

Discharge

I measured 207ah on my Turnigy, I stopped discharging when a cell hit 2.9v. The hump in the graph is where I stopped the discharge to walk the dog

Charge

The PL6 reported 206ah went back in

[Burgerman]

Looks pretty good to me.
That should wear out your dog! Actually it might wear the legs right off. Just a few stumps left after a walk.

My dog loved really long walks. But take water. I used to go to a tap in a park in summer half way around. And he drank it dry. When we got home I gave him a bucket of cold water. And he stuck his head right in under the water and kept doing it.

[stevelawiw]

Her legs are pretty short to begin with being a Beagle.
I'm going to have a refit on my chair. The batteries, and I have a new set of 10" Tubeless split rim wheels and other mods planned.