Battery pack on Panasonic NCR18650B cell

[docnjoj]

Yep what he (Doc) said. I have been running 6 Fatpacks for about 3 years now and never balanced. I do check them periodically and they remain well balanced and no BMS has ever been use. Thats 120 cells as 10S 12P in their original cases with the Bosch electronics removed and charged with a Bosch 4 amp charger.
otherDoc

 

[SamTexas]

There is a huge difference between cells that stay in balance and cells that self balance. Only a sleazy, totally dishonest salesman would say that Sony Konion cells self balance. Either that or totally ignorant (that's sugar coating for stupid).

Sony Konions DO NOT self balance. How many times does that need to be repeated. The only two chemistry that have self balacing characteristic are Lead-Acid and Nickel (NiCd or NiMh). They do this by releasing energy when certain voltage is reached. NO lithium chemistry in existence can do this.

So make up as many fantasies as you need in order to sell your Konion cells, but stop lying about "self-balancing" Konions. It's getting old.

I have many laptop LiCo packs that stay in balance after 100 cycles. It simply means that the pack was built with good cells that have the same capacity and internal resistance and that they age identically. It does not mean they self balance.

 

[Doctorbass]

Either that or totally ignorant (that's sugar coating for stupid

Again and again and again You never stop Mr Texas enh

Anyway.... I dont have any time to loose with your negative remark. I am offering great cheap and safe solutions that people like and appreciate and share alot of my time and have a positive attitude... I doubt this is your case Mr Texas...


By the way, I know Luke ( Liveforphysics) know more than me about lithium chemistry particularity and here is what he posted:

The charge efficiency of the spinel chemistries decreases slightly as it approaches a high SOC. You can see the effect with a CC supply and a temp sensor as plain as day.

This is what causes them to self balance. (and what causes a lead acid to self balance, only they use electrolysis as the energy outlet)

It is not a designed-in feature, simply an inherent property that helps to self correct balance in packs.

In practice, you can start with a pack that is out of balance, run a number of cycles through it, and each time its finishing the CV mode, you see balance creep a little closer each time until it ends up back in roughly perfect balance after enough cycles.

The exceptions of course would be if you have a weak cell, or a very fresh cell with old cells, etc etc.

Luke work at Zero motorcycle and he is the designer of the zero lithium battery... i think he know what he is saying...

Please re-read your own thread and read what all people responded... i see you did not argued for the rest of the thread.... curiously...

http://www.endless-sphere.com/forums/viewtopic.php?f=14&t=27702&hilit=konion

Doc

 

[etriker]

quote:
The exceptions of course would be if you have a weak cell, or a very fresh cell with old cells, etc etc.


Would you care to elaborate on the etc etc ?

What are the other exceptions ?

Would these exceptions require balancing the pack ?

If the pack needed to be balanced now and then would that mean it had reached the end of it's life ?

 

[etriker]

And what is a roughly perfect balance ?

You have a number ?

 

[SamTexas]

Read your own damn words!

Only the new Makita 2011 have balance lead but they use the same cells.. they just decided to help prolong their pack like a bit and reduce the deffective pack duw to lower cells vs aging

Why the f**k did Makita decide to add balance leads to packs containing cells that don't need balancing? Are they stupid enough to waste their own money?

I dont know why people sday they self balance... it'S not the afct...

They just DONT NEED balancing.. but they must be protected against over dishcarge and overcharge to avoid damaging them

What are you saying? They don't self balance, but they don't need balancing? If you have problem with english, write it in french. I can read it too. And make up you mind. You agreed with your sidekick about self balancing and you said it's not a fact! Which one is it?

They are as safe as A123 cells

Another outrageous lie!

You may have helped people in other areas, but as far as Sony Konion is concerned, you're just a dishonnest salesman. Quite a good job in the past six years, I might add.

 

[agniusm]

Need to chill boys Some anger in there. This is what i thought, if those sony cells are matched perfectly with same IR, capacity, same batch they would stay in balance but let one parameter go off and you need something to account for that.
If there is a thread and debate on these cells, lets not turn this one into another

 

[SamTexas]

This is what i thought, if those sony cells are matched perfectly with same IR, capacity, same batch they would stay in balance but let one parameter go off and you need something to account for that.

You are repeating what I already said.

There is a huge difference between cells that stay in balance and cells that self balance. Only a sleazy, totally dishonest salesman would say that Sony Konion cells self balance. Either that or totally ignorant (that's sugar coating for stupid).

Sony Konions DO NOT self balance. How many times does that need to be repeated. The only two chemistry that have self balacing characteristic are Lead-Acid and Nickel (NiCd or NiMh). They do this by releasing energy when certain voltage is reached. NO lithium chemistry in existence can do this.

So make up as many fantasies as you need in order to sell your Konion cells, but stop lying about "self-balancing" Konions. It's getting old.

I have many laptop LiCo packs that stay in balance after 100 cycles. It simply means that the pack was built with good cells that have the same capacity and internal resistance and that they age identically. It does not mean they self balance.

 

[agniusm]

This is what i thought, if those sony cells are matched perfectly with same IR, capacity, same batch they would stay in balance but let one parameter go off and you need something to account for that.

You are repeating what I already said.

There is a huge difference between cells that stay in balance and cells that self balance. Only a sleazy, totally dishonest salesman would say that Sony Konion cells self balance. Either that or totally ignorant (that's sugar coating for stupid).

Sony Konions DO NOT self balance. How many times does that need to be repeated. The only two chemistry that have self balacing characteristic are Lead-Acid and Nickel (NiCd or NiMh). They do this by releasing energy when certain voltage is reached. NO lithium chemistry in existence can do this.

So make up as many fantasies as you need in order to sell your Konion cells, but stop lying about "self-balancing" Konions. It's getting old.

I have many laptop LiCo packs that stay in balance after 100 cycles. It simply means that the pack was built with good cells that have the same capacity and internal resistance and that they age identically. It does not mean they self balance.

I was referring to my previous post when someone asked if they need to be balanced:

All lithium cells needs to be balanced in a pack, same goes for Sony Konion cells.

hence: this is what i thought!

On the other hand your posts are disrespectful to others so take a notch down. DoctorBass did a lot of work and wasted a lot of time for community and if you not agree with something he does, well, there is a way to express yourself in a more professional way.

 

[SamTexas]

I have no respect for liars.

 

[agniusm]

Then you must not respect yourself as lying is human nature to be rhetorical
OK, back on topic. I will be taking the cells to spot weld them professionally. They will be joined in parallel and series at once. Will they self balance in parallel groups when the groups are in series? I do balance them with BC168 but then again it's not perfect.

 

[SamTexas]

No idea what your question is about. "Self balance"? Of course not, but that's too obvious.

They will stay in balance if they are all at the same voltage before assembly, and if they are of the same capacity and internal resistance. But that's just repeating what has already been said.

 

[agniusm]

No idea what your question is about. "Self balance"? Of course not, but that's too obvious.

They will stay in balance if they are all at the same voltage before assembly, and if they are of the same capacity and internal resistance. But that's just repeating what has already been said.

Are you being a dick on purpose?
"Self Balancing
Unbalanced ageing is less of a problem with parallel chains which tend to be self balancing since the parallel connection holds all the cells at the same voltage and at the same time allows charge to move beween cells whether or not an external voltage is applied. There can however be problems with this cell configuration if a short circuit occurs in one of the cells since the rest of the parallel cells will discharge through the failed cell exacerbating the problem."

 

[SamTexas]

Of course not. Your question could not be any more ambiguous. Thus the response.

How about you? Are you a dick?

 

[Ypedal]

Ugh... come on guys.. quit the insults.

I've personally used, abused, and tested for hours these makita salvaged cells, minor imballances caused by heat distribution and the use of different cells from various packs combined ( having different cycle count, etc.. ) somehow work in harmony , i dont have the expertise to explain why or how but they do.. call it self ballancing or whatever you want, but they exibit behavior at end of charge ( when they reach 4.20v ) that cause them to heat up beyond that point, end result is that the lower voltage cells catch up over repeated cycles.

if you have a severely defective cell, self discharging at a high rate, it will cause pack problems.. but that's obvious.

Sam, reply and discuss all you want, but no more spitting flat out insults please.

 

[etriker]

I made a 7s 1p small extender pack with the makita cells and let it charge and discharge in parallel with a main 8s 6p A123m1 pack.

It has been on the bike for months now.

Took it off and checked the voltages right now.

All 7 cells are 4.057 v measured with a fluke meter.

They do tend to stay in balance.

 

[etriker]

I soldered 12g wire right on the cells because I wanted to see if soldering on them would mess them up.

So far so good.

 

[docnjoj]

Here is a paper that explains in depth how Konions self balance.

http://www.osti.gov/bridge/servlets/purl/764356-L8GBN7/native/764356.pdf

otherDoc

 

[agniusm]

I read about that REDOX chemical balancing solution but thought it was on paper only and never used in practice.

 

[chroot]

@SamTexas - Let's take walk outside, get your head cool and no need get angry or criticize at anybody. Everyone have their opinions no matter if we disagree or agree. Move on......

 

[docnjoj]

I read about that REDOX chemical balancing solution but thought it was on paper only and never used in practice.

No that is the chemistry used in Konions and some Panasonic cells. This is older material so some of the newer batts may use it updated. I would not substitute the newer "self balance" cells for a good balance charger and Celllog alarms or LVC but the fact is mine are still going fine after 3+ years with no balance charger or BMS. I would never try this on LifePo4 or even LiPo. I do run my Konions in parallel with an old (near 5 years) Ping and they are charged separately. The Ping, of course has a BMS.
otherDoc

 

[agniusm]

Some progress on the battery:

They were matched by IR in parallel groups, although IR is 36-37mOhm range, measured with pro equip.

 

[agniusm]

Hard cases left to figure out

 

[agniusm]

The battery pack turned out to be 51% lighter than equivalent capacity A123 bare cells.

 

[Gab]

Hi Agniusm

So its 50% lighter then a123, are you talking the pouch cells or a123 26650 cells ?

Also how much smaller is the volume comparing them ?is it same or smaller volume battery box for same capacity?