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

upnorthandpersonal

upnorthandpersonal

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... than to go into discussion with SFK on Andy's YT comment section.

For context, the issue is that the JK (new one) resets its values after x amount of time un-powered. This is a bug, obviously, and the reset values of 4.2V per cell are very bad for LFP. So SFK commented under the video:

The JK BMS (all of them) does Ram/Over Volt Active Balancing where it will send 4.2V to LFP cells to balance them. So I don't think it would have caused the cells to explode at 4.2 it certainly is not good for them. However It would shorten the life of the cells. Please test with a volt meter Andy on any JK device to see the Ram Balancing technique with the JK active balancers, you can simulate the same using a power supply sending 4.2- 4.8 volts for faster cell balancing (not good for the cell)...
Click to expand...

Which is not correct. It's not the 4.2V balancing voltage that's the issue. The cell will never see that voltage, because cell over voltage protection for one, and two, during balancing the cell will pull this voltage down (just like with a power supply). So I replied explaining this as well as I could in a YT comment:

A cell that is not at e.g. 3.5V yet will pull down the voltage of the supply (balancer) to its level, even if the supply is set at 10V (constant current mode). If you now have a cell at 3.5V and apply 4.2V to that cell continuously (because your settings are gone) the cell will keep going up in voltage until it reaches 4.2V as well (or before it gives in before getting there). So for a balancer, it's not an issue since the cell itself won't get to a value over 3.5V (if that's where the cell high voltage disconnect is) even if the balancer voltage is 4.2V. If however the cell protection sits at 4.2V after a reset, the cell will get to 4.2V, and likely vent/bloat (charger settings ignored in this discussion of course, but after a reset, it could request the higher voltage from the charge controller if comms are set up).
Click to expand...

To which they replied:

This is absolutely incorrect, incoming voltage should never exceed 3.65v on LFP cells, doing so will damage the cell. LFP cells must be charged using the CC/CV constant current / constant voltage method meaning once they reach a fully charged voltage of 3.65 volts only the incoming amps should be adjusted as needed as to maintain this voltage. Over-volting a cell to speed up balancing is harming the cell because the cell is forced to absorb amps higher than it would do under normal charging circumstances.This is why the JK is able to do constant 2 amp balancing because it Ram Balancing / Over-volt balancing.The capacitor style balancing is far better for the cell, it is slower but safer way of balancing cells as the cell never sees an input voltage greater than 3.65.
Click to expand...

Which completely ignores what I was trying to explain, so I replied:

Take a e.g. 10A lab power supply, take an LFP cell at 3.1V. Put the lab supply at 4V before connecting. Connect to the cell. What does a multimeter show as a voltage at the cell?
Click to expand...

And of course they missed the point and replied:

Why stop at 4v why not put 8v, how about 10v? It is truly remarkable how uninformed you are, I guess now we have to make video explaining why this is bad.
Click to expand...

Seriously, those guys...
 
Andy often creates "issues" just to make "interesting" videos.
Have tried to post comments under his videos that points out issues/errors but no replies and he just keep on trucking.

I no longer consider him serious, just watch his videos some times for the light entertainment value.

When it comes to the new JK firmwares on the new model I am sure they will fix it promptly.
Seems like a programming snafu.
The old hardware model versions are not affected.
 
LydMekk said:
When it comes to the new JK firmwares on the new model I am sure they will fix it promptly.
Click to expand...

Someone mentioned that previous versions of the firmware on this BMS don't have the issue, so yeah, it likely will be. The main issue I have with these panics: let me know of any other BMS even coming close to these features at this price point and even outside this price point, that have done this without bugs in their release. Heck, even the Batrium has seen (and still has) plenty of issues.

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.
 
Just a gentle reminder that there are always two parties involved in a transaction... the business.. and the customers...
It only takes a few very difficult customers to sour things for a business... after that .. room for manoevre becomes limited.. also vice versa... once burned as a customer... the same applies...
It does seem that the internet cannot match a face to face interaction.. too much room for misunderstandings...
 
upnorthandpersonal said:
Someone mentioned that previous versions of the firmware on this BMS don't have the issue, so yeah, it likely will be. The main issue I have with these panics: let me know of any other BMS even coming close to these features at this price point and even outside this price point, that have done this without bugs in their release. Heck, even the Batrium has seen (and still has) plenty of issues.

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.
Click to expand...
Ohh my now a few are doing the "Chicken Little Drama Dance" over the JK and going as far as bashing all of their products and retro-bitching on quirks.

This is the end result of all the TV Stations ending Soap Opera's, those all went to the Internet to "Live the Drama or make it if they can't find it".

TO BE HONEST - I WAS Expecting a Genuine GEM from the SFK twit's on the JKBMS Inverter Edition... Just the kind of thing for him to leap on be be foolish about.
 
Steve_S said:
Ohh my now a few are doing the "Chicken Little Drama Dance" over the JK and going as far as bashing all of their products and retro-bitching on quirks.

This is the end result of all the TV Stations ending Soap Opera's, those all went to the Internet to "Live the Drama or make it if they can't find it".

TO BE HONEST - I WAS Expecting a Genuine GEM from the SFK twit's on the JKBMS Inverter Edition... Just the kind of thing for him to leap on be be foolish about.
Click to expand...
YouTube is all about the drama unfortunately... the algorithm demands it... no drama ..no clicks..
makes for a very divisive society...
that’s why I like this forum.. full of good people and good info..?
 
I view YT as entertainment. Do I learn things, sure but that just triggers going somewhere for real verification. If the average DIY'er is trying to become professional, well those people better be looking elsewhere.
 
upnorthandpersonal said:
... than to go into discussion with SFK on Andy's YT comment section.

For context, the issue is that the JK (new one) resets its values after x amount of time un-powered. This is a bug, obviously, and the reset values of 4.2V per cell are very bad for LFP. So SFK commented under the video:



Which is not correct. It's not the 4.2V balancing voltage that's the issue. The cell will never see that voltage, because cell over voltage protection for one, and two, during balancing the cell will pull this voltage down (just like with a power supply). So I replied explaining this as well as I could in a YT comment:



To which they replied:



Which completely ignores what I was trying to explain, so I replied:



And of course they missed the point and replied:



Seriously, those guys...
Click to expand...
ezels en zich aan dezelfde steen stoten :)

oh man , you should have know better than to argue with SKF ;-)

as to the JK , i have stated before that i think it still is too Beta in development for me, as well the price point is not market conform yet, but i think both will become competitive over time
 
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Guilty as charged ? I have Neey balancer with my v3 eel kit which work similar to the JK (I think) and what @MrSwede experienced:
https://diysolarforum.com/threads/seplos-bms-goes-bananas-when-neey-is-working.74960/
https://diysolarforum.com/attachments/20231216_222236000_ios-jpg.183410/ NOTICE 1 cell is reading 4.04v

Seems that some of the active balancers ramp up the voltage to get a cell to balance quicker. I've been charging lipos/life in RC for 20 years we always set the voltage to full cell voltage, so If these active balancers are ramping up voltage to charge the batteries Its a NO NO for me.

Btw I think you are actually agreeing with each other and it seems to be a miscommunication?
 
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