I should have known better... (sorry, ranting)

[Steve_S]

External Active Balancers CAN be tricky... For example the QNBBM's cannot be set/programmed or jumpered for Battery Chemistry, nor for start/stop set points or at what delta difference you want. They do their thing and no control over it.

Now we are seeing folks "LUMPING" issues with externalities...
Making ASSUMPTIONS, Jumping to CONCLUSIONS (far too common these days) only serves to make one a @SS which is what assumptions are best for.

This is an SFK is an IDIOT and here is more proof yet Thread... STICK TO IT or start another thread to debate Assumptions & Conclusions drawn from them.

 

[shvm]

And of course they missed the point and replied:


Seriously, those guys...

My reply would be this simple:

"Yes, Please. Demonstrate it live on a video."

Getting embarassed on a live video intended to prove somebody else wrong has to be my favourite content.

If only most people actually put efforts in experimentally verifying what they believe in before boldly claiming it to be true, the world would collapse immediately.

 

[Alkaline]

Yes a video would be good.

 

[rhino]

In many ways, it's early days, and these are part of the 'costs' of DIY. That's not to say that off-the-shelf is somehow 'perfect' - as Andy and Will have often found out. The panic however doesn't help anything.

A company needs to decide if they want to prioritize quality or not. Why not provide free and/or even paid testing by people who they know even from previous experience can find issues or provide feedback? Instead they just put it out on the market and waited for people to find them.

 

[SparkyJJO]

A company needs to decide if they want to prioritize quality or not. Why not provide free and/or even paid testing by people who they know even from previous experience can find issues or provide feedback? Instead they just put it out on the market and waited for people to find them.

It is cheaper to have the public beta test.
At least in the short term.

 

[upnorthandpersonal]

Here's my video:

 

[shvm]

Here's my video:

Thanks. If you ever get factory new cell shipments, please let me know.

I've got an entire list of testing videos that I'd like to be made using lab grade equipments.

 

[upnorthandpersonal]

NOTICE 1 cell is reading 4.04v

Why would an active balancer charge a high cell (anything at/over 3.65V for sure - where is the over voltage protection?) at all, especially when this cell is not even close to being the lowest in the set?

Why not provide free and/or even paid testing by people who they know even from previous experience can find issues or provide feedback?

Funny thing is, they did ask me at one point to make a test report (and all they would have had to do is send me one, I don't need to be paid for this). I tentatively agreed, but didn't hear back. They also sent one to Andy around this time with this same purpose before they became available, but then suddenly they went up for sale anyway.

Thanks. If you ever get factory new cell shipments, please let me know.

I've got an entire list of testing videos that I'd like to be made using lab grade equipments.

I get new cells all the time, including stuff that's not on the market yet (NaI) and stuff I can't even discuss - I'm currently working on an entire new battery test lab here at the university because the old one is getting too small.

 

[shvm]

I get new cells all the time, including stuff that's not on the market

Then let me know when you get the willingness and free time to conduct some basic experiments.

 

[zedconnor]

This might be a dumb question :D , if you input 10V into an LFP, the cell converts the volt to whatever it wants, and then amplifies the "Amp"?
I mean if you put 10V 10A into the cell, it converts it to lets say 3.5V 28.5A? According to the formula P=VA?

 

[upnorthandpersonal]

This might be a dumb question :D , if you input 10V into an LFP, the cell converts the volt to whatever it wants, and then amplifies the "Amp"?
I mean if you put 10V 10A into the cell, it converts it to lets say 3.5V 28.5A? According to the formula P=VA?

The cell will draw whatever it can (low internal resistance). If you were to have a 20Ah cell (like in my video) and have a 100A capable supply, it would happily deliver this 100A (5C) - not good for the battery cell, but it would still do that.

The point is, because the supply (any supply, be it the balancer or this lab supply) is limited in the current it can supply, the voltage must drop to the battery voltage (in other words, the voltage can not be sustained, because the load is too high).

You can't put 10V 10A in the cell. The 10V can not be sustained, it will drop to the battery cell voltage, and then the supply will dump as much current as it possibly can into the cell. This is C.C. (constant current) mode.

 

[zedconnor]

The cell will draw whatever it can (low internal resistance). If you were to have a 20Ah cell (like in my video) and have a 100A capable supply, it would happily deliver this 100A (5C) - not good for the battery cell, but it would still do that.

The point is, because the supply (any supply, be it the balancer or this lab supply) is limited in the current it can supply, the voltage must drop to the battery voltage (in other words, the voltage can not be sustained, because the load is too high).

You can't put 10V 10A in the cell. The 10V can not be sustained, it will drop to the battery cell voltage, and then the supply will dump as much current as it possibly can into the cell.

So with a charger capable of 5V@60A, but I configured it to 4V@20A for charging, the cell will draw over 20A but not above 60A. ?

 

[upnorthandpersonal]

If you put the current limiter to 20A, that's the max it will be able to draw. But if you set the current limiter all open, it will draw all it can.
So yes, this is constant current mode: you want to have the charger set at e.g. 0.5C (for 100Ah cell, that's 50A), you set it at that. The voltage setting at this point is irrelevant (when you have proper connections) - it will be cell voltage anyway. You can only set the current limiter.

However, the danger comes in once the cell charges and its voltage goes up. Now you get to the Constant Voltage stage, and if your supply is set at 4V, you will see the voltage creep up/shoot up to 4V and at that point your cell will bloat like a balloon.

 

[Steve_S]

Funny thing is, they did ask me at one point to make a test report (and all they would have had to do is send me one, I don't need to be paid for this). I tentatively agreed, but didn't hear back. They also sent one to Andy around this time with this same purpose before they became available, but then suddenly they went up for sale anyway.

Similar, I was asked to look, evaluate, post photo/video. If I posted a good review It would be free otherwise full pop...
Both of us contribytred to the last manual and helped them to get things sorted and as far as I know, neither of us even got a free bms or anything... I did get some BMS switched, SORRY MY BAD... I've several on order, they were actually picked up from the warehouse but the shipping of them is waiting till this issue & others are resolved.... I have a bunch of current standard versions, so worse comes to worse, I'll use those temporarily.

Well, any issues would have been outted instantly and in detail...
Now some hysteria & Ultra Dramatics is going to really do a PR job and hurt JiKong for not having a respectable Quality Assurance & Check process

 

[Quattrohead]

Pace, Seplos and JBD etc have been making this style of BMS for a few years, plenty of choices.
All of them have sucky Windows 95 style software and piss poor documentation, but they work well.
You multi-amp active balance folks have got the manufacturers in a tizz
Can we just have up to date software and English docs first please.

 

[timselectric]

I just wish that this stupid thing would get resolved.
It's wasting too much bandwidth.
I have no interest in it. And can't wait for more interesting content to come back.

 

[Danke]

.
You multi-amp active balance folks have got the manufacturers in a tizz

LOL. I had to go back-and-forth for weeks to finally get manufacturers to put active balancing modules in the batteries their building for me. Salespersons kept saying, “engineers are saying it’s not necessary, etc.”

 

[Sam Cho TX]

I saw that comment and was going to post something about that here.. this is why people have SFK on their DO NOT BUY list..

cc:
@Sam Cho TX

Well looks like I have been summoned by rhino. What exactly do you want me to do here I don't have a JK BMS I have seplos in mason kits and jbd in my 12v. I'm not some SFK patsy, they have asked me repeatedly to keep them out of diysolarforum threads... No issues at all with SFK from my orders and I'm going to be over 120 by the end of this month/early feb, neither has been for various others I know, there is a local guy just ordered 288 of the rept cells from them in the Ozarks after seeing my setup in progress.

As for upnorthpersonal he has been beefing with SFK for as long as I have been here. Previously he said to get Amp-hour watt-hr / nominal voltage is wrong and I asked on quora from electrical engineers and many other places including chat gpt and they all said its fine and works. https://diysolarforum.com/threads/wh-and-ah-and-more.74939/post-950297

&

Wh and Ah and More

Please tell us about SFK's "shadyness" This was when the LF280k cells didn't pull 280Ah. Back before it became well known that EVE had issues with the 280k not pulling full capacity. So people measured SFK cells, and didn't reach 280Ah even if the test report said they would (which EVE...

diysolarforum.com

So I'm ask again if its ok to charge your lithium cell at 10v instead of 3.65v (like everyone else who told me to do so on the zke) I hope the video that was posted stays up and doesn't magically disappear. On the flipside, if it is ok; why the heck aren't we always charging cells this way?

 

[740GLE]

I just wish that this stupid thing would get resolved.
It's wasting too much bandwidth.
I have no interest in it. And can't wait for more interesting content to come back.

Id say jump over to the new Cummins dieselgate videos, lots of entertainment over there.

 

[timselectric]

Id say jump over to the new Cummins dieselgate videos, lots of entertainment over there.

Not interested in that, either. lol