LiFeBatt Battery Woes

[BMI]

Before this thread turns into another slanging match and gets locked, can anyone give me a sound technical explanation why these cells are not recommended to be installed vertically?

You are absolutely right Malcolm. The last thing I also want is for the thread to get locked up so it is probably best that I don't rebuke Mr Harmon with answers to his comments and questions. I am more than happy to answer all of his concerns and certainly have several emails on record from Lifebatt customers who I have helped out (and we are not just talking about e-bike customers exclusively but all customers).
If the forum moderators can guarantee the thread will not be locked I will come back and answer in full. But for now that is the last I will say on the matter so as to not provoke Mr Harmon into a full on slanging match which is not helpful to any of us.
Malcolm I have not been provided by any directive or other instructions from the factory stating that either the loose cells or HPS or SB battery packs must be operated so the cells are kept horizontal. In fact my BMI engine start battery in my own Toyota Camry is installed on its side since it fits better this way as you can see from the attached photo. It has been in my car operating this way for just over a year and starts my car everytime, day in, day out, without fail and without any signs of "cell/electrolyte creep" or any other name this so called phenomenon is called. I have even used a small piece of timber as packing since the BMI LiFePO4 battery is considerably smaller than the original lead acid starting battery (one day I will get around to making a proper bracket).

View attachment IMGP1413.JPG
If Mr Harmon chooses to not provide any waranty for Lifebatt HPS battery packs if they are used in any orientation other than horizontally that is his choice and there is no argument from me. For customers who want to use a BMI HPS battery fitted to a bike, car, boat or any other application horizontally, vertically, inverted (or anywhere in between) that is fine by me and the same full warranty will apply when used in any of these orientations.

We can also consider the case of other LiFePO4 cells. For instance even though they are considerably smaller, A123 M1 cells are similar in construction to BMI and Lifebatt cells and also feature a fully laser welded case.
I have seen some pretty wild aerobatics manoeuvres performed in model RC helicopters powered by A123 cells and never have I seen or heard of a case where the helicopter has dropped from the sky because of "electrolyte moving around in the cell"!
Even for their intended application in Dewalt power tool packs a cordless drill being used on a construction site would often be used with the cells in the battery pack in orientations far exceeding the horizontal plane, eg. when drilling or screwing into a ceiling or roof. I have never seen any Dewalt power tool instructions state that the battery pack/power tool must only be used horizontally.

So I don't believe micro13car should be too concerned about the orientation of the cells used in his custom assembled battery pack.

Enough said.

 

[Malcolm]

Many thanks Armin. The real-life example of your car starter battery and your willingness to warranty use in any position are reassuring. I'm still a bit curious about the reason behind this recommendation, but I'm willing to accept the small risk and install some of my own cells vertically. It makes packaging them a lot easier in my bike. I will make sure that the cells are supported by their end cans rather than their studs though.

 

[BMI]

Many thanks Armin. The real-life example of your car starter battery and your willingness to warranty use in any position are reassuring. I'm still a bit curious about the reason behind this recommendation, but I'm willing to accept the small risk and install some of my own cells vertically. It makes packaging them a lot easier in my bike. I will make sure that the cells are supported by their end cans rather than their studs though.

I just think it is scare mongering with no real basis of fact.
The real issue is to support the cell by its body and not by its terminals. This is the biggest mistake I see people make who use this type of cell. When people purchase BMI cells from me I always include a cell instruction leaflet explaining how to install the cells properly and including the recommended terminal nut torque setting and cautions to observe. I don't believe any of the other suppliers of 40138 cells provide any type of instructions when they provide cells to their customers which is why I quite often hear of cases where terminals have been way over tightened and broken off as a result.
This is why I highly recommend the use of cell holding frames or the "lego blocks" when making up battery packs with these cells.
People often support their LiFePO4 battery packs by the battery terminals which is when problems occur.
After all you would never lift a lead acid battery out of a car by its terminals so why subject LiFePO4 battery terminals to similar stress?

 

[Gow864]

.... I know how many packs I have sold to e-bike customers and can count them on one hand.....

I'm not surprised :lol:

 

[TylerDurden]

You buy cells through PSI now under BMI's permission and the cells that we were diccussing in this post are identical to the ones that you sell.

You can play games with everyone here if you like but ultimately they will see that the LiFeBATT cells in Miro Car's pack are identical to your "so called superior" Gray cells.

In fact Miro's are Gray too- just with a LifeBATT lable on them instead of a BMI lable. Don't let him fool you Miro - you got the same thing in the pack you bought from LiFeBATT.

So, the gray cells from LifeBatt are identical to the grey PSI cells.

Straight from the horse's-ass.

 

[AndyH]

... I don't believe any of the other suppliers of 40138 cells provide any type of instructions when they provide cells to their customers which is why I quite often hear of cases where terminals have been way over tightened and broken off as a result...

Sorry Mate - you know that PSI has been providing instructions since 3 Sep 07, and that at least one supplier has provided instructions since at least 24 Nov 08 - it was pointed out to you on 12 May 09.

http://www.endless-sphere.com/forums/viewtopic.php?f=14&t=6586&start=45#p157899

http://www.endless-sphere.com/forums/viewtopic.php?f=14&t=8278#p126598

 

[BMI]

... I don't believe any of the other suppliers of 40138 cells provide any type of instructions when they provide cells to their customers which is why I quite often hear of cases where terminals have been way over tightened and broken off as a result...

Sorry Mate - you know that PSI has been providing instructions since 3 Sep 07, and that at least one supplier has provided instructions since at least 24 Nov 08 - it was pointed out to you on 12 May 09.

http://www.endless-sphere.com/forums/viewtopic.php?f=14&t=6586&start=45#p157899

http://www.endless-sphere.com/forums/viewtopic.php?f=14&t=8278#p126598

Thanks for updating me with that Andy. I wasn't aware of that and it is the first time I have seen these instructions from PSI so it is good that they are also supplying installation instructions. So there should be no reason for people to damage cells unless they just don't read the instructions.
Perhaps there is more a problem with a lack of instructions being supplied some of the businesses assembling the battery packs which are supplied by cells from PSI rather than from the actual manufacturers (like PSI)? I have two battery packs just arrived for a service/testing from a customer which are made up of green PSI cells. The customer purchased these packs from a Cyclone distributor and they came without any BMS fitted or battery instructions. In fact the owner of the batteries wasn't really aware of what a BMS is and its function. Anyway it will be interesting to see how out of balance the cells are from the many cycles put on these packs without the customer understanding the need for BMS or other method of cell balancing. I will soon see that state of the cells when I undo all the duct tape and check the individual cell voltages and internal impedances.

 

[miro13car]

At the very minimum my yellow pack had served me for 2000km and doing just fine and better due to warm weather here.
Grey cells seem don't mind sitting upright /Well not exactely upright if you look at me pictures page 1/.
From my experience there are 2 key factors to get high performance from them:
-temperature
-balance
It is pleasure to cruse around untill bottom is sore, this thing seems never get deplated /in over 20C temp./
Strong power delivery even after 8Ah drawn.
I open and inspected pack 3 times and added more cushion.
terminals of my cells never touch each other although they are close.Of couse they are jumped so electrically it doesn't matter if they touch.
MC

 

[miro13car]

What? PSI cells connected with no any kind BMS?
I found out that that balancing on regular basis is a must for HPS packs.
Beauty of HPS is modular design, plug and play kind of.
Just how simply is to build 36V10Ah HPS pack.
you buy 12 cells, 3 VMS sets/with ribbon cables, termistor/, one board with buzzer, 12 craddles.
you mount cells in craddles, connect them with flexable jumpers made of AWG8 wire, install one fuse link 65A/the highest rating I could find at Canadian Tire, original HPS pack fuse is 160A much to much for ebike/, place craddles with cells in your enclosure, plug in ribbons, plug in thermistors/one for every 4 cells/, I am sure Armin can sell you original gold plated battery terminals used for HPS.
What I would love to see are LEDs which are soldered on VMS to make them external. Kind of LED harness for every VMS which is pluged into board. That would require redesigning the board .
I desoldered LEDs from all VMS es and soldered ribbon instead of them and placed LEDs on small PCB which is mounted in window of my box so I can easly see state of pack from where I sit.
MC

 

[Malcolm]

I wouldn't normally publish the content of a private message, but in this case I think it's important enough to do so, particularly as I asked for the information publicly. I got this explanation from Battboy (Don Harmon) regarding the reason to avoid installing Lifebatt cells vertically:

"You want the technical reason - The top of the foil gets uncovered and goes short circuit, and at high temps the electrolyte will leak from the bottom of the cell. This from the scientist himself who designed the original LiFeBATT 40138 Cell which is mfg. by PSI."

I still don't understand this, but hopefully someone with a better knowledge of cell construction can make sense of it. Could it be a corrosion problem, like that found on certain of the earlier Thundersky cells?

 

[BMI]

I wouldn't normally publish the content of a private message, but in this case I think it's important enough to do so, particularly as I asked for the information publicly. I got this explanation from Battboy (Don Harmon) regarding the reason to avoid installing Lifebatt cells vertically:

"You want the technical reason - The top of the foil gets uncovered and goes short circuit, and at high temps the electrolyte will leak from the bottom of the cell. This from the scientist himself who designed the original LiFeBATT 40138 Cell which is mfg. by PSI."

I still don't understand this, but hopefully someone with a better knowledge of cell construction can make sense of it. Could it be a corrosion problem, like that found on certain of the earlier Thundersky cells?

Why did Batboy/Mr Lifebatt/Don Harmon not explain this to everyone openly on the forum if he believes this is a legitimate concern? You get respect from your customers by being open and honest with them, not by hiding things...... anyway...

If this is a legitimate concern how can the foil get uncovered in what is a closed cell (other than the safety pressure relief vents which will only operate to release excess pressure when the cell is used in adverse conditions outside of its normal operating specifications)? This would indicate there must be air mixed with liquid in the sealed cell to be able to become "uncovered". The cells are rock solid and definitely no sloshing of liquid can be detected if you shake one.
Lets say for a moment that the foil does somehow get uncovered. If this is so then how does it go short circuit? What shorts it out?

If Mr Harmon seriously believes this why is there no warning on the Lifebatt website advising that HPS batteries must only be used upright or else warranty will be voided?

 

[Malcolm]

The empty space around the anode/cathode roll is filled with what smells like an organic solvent. I know this because I slightly overcharged a cell and it vented a few drops of this liquid. I'm guessing that the main purpose of this liquid is to exclude air and prevent corrosion of the lithium anode. It may also aid heat transfer. I'd also guess that the aim during manufacture is to eliminate all air from the cells, although this may be difficult. If this speculation is true then the cells would only be at risk if they were incompletely filled or if they vented at some stage as a result of being stressed.

 

[BMI]

The solvent you can smell is Polyvynilidene Difluoride. This is the only liquid component of the cell and makes up a total of no more than 10% of the cell by weight. The other 90% of all materials which go to make up the cell are solids.
The cell will only release a small amout of this solvent if it is subjected to excessive stress (such as being subjected to a short circuit for instance). Under all normal operating conditions the safety pressure release valves will not open and none of this liquid will be vented to the atmosphere. So it doesn't matter if the cell is used horizontally, vertically or on an incline so long as it is operated within its design specifications none of the material which is contained in the cell can be lost to the outside atmosphere.

 

[Malcolm]

I don't think the liquid can be PVDF, or at least not PVDF alone, as it's a polymer with a melting point of 170C. PVDF seems to be used as a component in the electrolyte gel.

 

[BMI]

I don't think the liquid can be PVDF, or at least not PVDF alone, as it's a polymer with a melting point of 170C. PVDF seems to be used as a component in the electrolyte gel.

It is PVdF (CAS No. 24937-79-9)

 

[Ypedal]

My only " Guess " as to why vertical mounting may be bad, the surface area supporting the cell weight vertically if it was stacked multiple cells high and hard bumps from the road, could possibly deform/stress the cell causing problems over time.. on Micro's setup this is not a problem..

I agree about there being no empty spaces or sloshing effect when the cells are shaken ( i am holding one right now.. )

I think that Don takes his " Scientists " a little too seriously, a combination of casual conversation and broken english can result in some speculative BS imo..

Either way.. i got an email form battboy that he would NEVER AGAIN post on ES !!!! if he does he owes Bob McCree a free XPS pack !! of Bob's V and Ah choice ! charger not included. so he likely won't be replying to this post anytime soon ! fyi.

 

[recumbent]

According to the cell i dissasembled a couple months ago (pictured below), Don Harmon is indeed correct.

If you look carefully at the tips of the copper connector leafs, they are all corroded at the area where the organic liquid theoretically was topped.

These cells are 1-1/2 yrs old and used only in the vertical position (5,000 kms), and couple of them failed.

To be honest, the cell i ripped open had the organic stuff mostly gone, perhaps a defective cell, but never leaked.

None-the-less it was indeed corroded, exactly as Don said. The discolored part of the copper connectors crumpled with finger pressure.

I know this is a different cell, but still, something to think about.

 

[recumbent]

The PSI cells do not seem to use copper as connectors and they are much thicker.

The copper leafes pictured were thinner than paper.

Here's another picture...

 

[BMI]

According to the cell i dissasembled a couple months ago (pictured below), Don Harmon is indeed correct.

If you look carefully at the tips of the copper connector leafs, they are all corroded at the area where the organic liquid theoretically was topped.

These cells are 1-1/2 yrs old and used only in the vertical position (5,000 kms), and couple of them failed.

To be honest, the cell i ripped open had the organic stuff mostly gone, perhaps a defective cell, but never leaked.

None-the-less it was indeed corroded, exactly as Don said. The discolored part of the copper connectors crumpled with finger pressure.

I know this is a different cell, but still, something to think about.

You cannot compare a high quality cylindrical cell with a prismatic cell from China. We are talking only about Lifebatt/PSI and BMI cells here with regard to the orientation they should be used in. They are two very different animals!
The way they are manufactured is entirely different and the quality control which goes into each of these batteries is very different as well. The Lifebatt cells are made in a fully computer controlled, automated plant which is why consistency between all cells off the production line is very high. Even the nuts on the end of the cells are screwed on to the threaded terminals and precisely torqued by robots with no sight of any human intervention.

Thundersky make prismatic cells and it has clearly been stated that their cells must always be used upright or else liquid can and will be lost from the cell. Just ask any of the full size EV owners who use Thundersky cells.
Also prismatic cells are prone to earlier failure since they have "corners" and cell containers are not fully welded. The layers in a cylindrical cell can be wound far more tightly eliminating all air spaces and making for a more solid cell which has much greater resistance to vibration and therefore premature failure. (You can notice the air spaces between the cell layers near the cell corner in the photos of the prismatic cell which was cut open)

If you take a dozen cylindrical Lifebatt cells and a dozen prizmatic cells which are brand new and measure the internal impedance of every cell, I guarantee there will be far greater consistency, lower impedance readings and less variation in the measurements recorded with the Lifebatt/BMI/PSI cells than any cells which come in a "rectangular can".

 

[miro13car]

PSI itself uses them upright on burning/cycling rack.

 

[recumbent]

The reason i posted the pictures was to show that vertical orientation argument is probably based on fact. But only the copper corroded, not the aluminum connectors.
Just showing real life pictures of what we're talkin bout, that's all.

BTW, i own 16 PSI cells mounted vertically in my panniers

 

[miro13car]

He never used word "corroded" but "uncovered",
we are discussing here cilindrical PSI/BMI cell.
as Armin says it would eventually happen only if relieve valve opend leaked some solvent which would allow for empty space that's when foil would get "uncovered".
Otharwise cell is fully filled.
Why foil cannot get uncovered in vertical position? If it cannot , because no empty space, all filled.
As Yedal wrote combination of broken English ....from Taiwan
Again , if you know and read SOP Standard Operating Procedure from PSI , there is no one warning about mounting cells vertically. No there is one warning in other 2 documents like Application Note which I got from LB which explain how to configure packs. If there were such warning Don would have published it here very gladely.
Miroslaw

 

[BMI]

The reason i posted the pictures was to show that vertical orientation argument is probably based on fact. But only the copper corroded, not the aluminum connectors.
Just showing real life pictures of what we're talkin bout, that's all.

BTW, i own 16 PSI cells mounted vertically in my panniers

Recumbent I really don't think you have anything to worry about having mounted your PSI cells vertically in panniers. I would certainly do this myself if this is the way they fit the best on a bike. Have you noticed any problems or experienced any cell failures while they have been in use this way?

 

[recumbent]

Recumbent I really don't think you have anything to worry about having mounted your PSI cells vertically in panniers. I would certainly do this myself if this is the way they fit the best on a bike. Have you noticed any problems or experienced any cell failures while they have been in use this way?

Yes, I had one cell fail after only one week of use, now you know my concern is more than just talk.
However it was promply replaced by my wonderful supplier and everythring is fine for the past 500 kms.

I think this was just a warranty cell, which happens to any production line. The cell was perfectly balanced and all, then after a few days it would not hold a charge, degraded very rapidly but no leaks and no loose studs, mounted correctly on plastic end caps.

 

[BMI]

Recumbent I really don't think you have anything to worry about having mounted your PSI cells vertically in panniers. I would certainly do this myself if this is the way they fit the best on a bike. Have you noticed any problems or experienced any cell failures while they have been in use this way?

Yes, I had one cell fail after only one week of use, now you know my concern is more than just talk.
However it was promply replaced by my wonderful supplier and everythring is fine for the past 500 kms.

I think this was just a warranty cell, which happens to any production line. The cell was perfectly balanced and all, then after a few days it would not hold a charge, degraded very rapidly but no leaks and no loose studs, mounted correctly on plastic end caps.

Ok, well that clearly sounds as if it is a case of a bad cell which got out of the factory since all the other cells have been working fine. I can't speak for the factory quality control procedures since the green cells are manufactured in a different factory by PSI compared to the newer grey BMI and Lifebatt cells which come from a brand new factory. It is good that your defective cell was replaced under warranty and all has been fine with your pack since.