Orientation

chrisblessing

Solar Enthusiast
Greetings. I just completed my first 12v 100aH battery bank using K2 Energy cells. My desired location for placing the battery in my small camper is barely tall enough to accommodate them while upright. I wonder about the feasibility of laying the battery bank on its side (edge). There is scant, and often contradictory information about this. Any input from here?

Many thanks.
 

svetz

Works in theory! Practice? That's something else
If the K2's are LiFePO4 they can operate in any orientation. The electrolyte won't leak out like an FLA.

But, usually the terminals are up so gravity doesn't wear away any safety coatings from vibration that might cause them to short out. A fuse won't save you if the battery's terminals are shorting out.
 

b.james

Solar Enthusiast
Dont see any coatings ? But yours may be 26650 rolled cells but either way they should be good . You use torch batteries in any orientation.
 
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chrisblessing

Solar Enthusiast
Thanks to svetz and b.james. To clarify, the K2 Energy cells are LiFePo4 3.6v 90Ah, wired in series. I'm not certain what the photos portray. I guess the concern of some is that the electrolyte will not be evenly distributed correctly if the batteries on are on their edge, rather than upright.

Thanks again.
 

svetz

Works in theory! Practice? That's something else
... usually the terminals are up so gravity doesn't wear away any safety coatings from vibration
By "coatings" I meant something that "covers" the battery terminals. You just don't want the battery's terminals shorting out because they're rubbing against the box they're sitting in:

Capture.PNG
 

b.james

Solar Enthusiast
Depends on construction. Prismatic Cell;
Yeh well yaknow thats one man's opinion and leads you to think the cells are not packed properly and they know it.
Alloy cased prismatics are pushed in tight . The position of the vent is meaningless because any gas that is created by overheated plates will go to where ever it can escape from . I'm sure you will agree with that.
Gotta be careful there being a fellow ham and all. Don't want to offend but they are alloy prismatics and they do run on their sides if you want. Upside down I might avoid as the plates can come down on the backs of the terminals ,although ,they are bolted through tabs at the top of each plate..
 

grizzzman

Some say "Why" and some say "Why not?"
The truth is all prismatics are pushed tight. the plastic version needs to be clamped to avoid swelling. ( Wills electrical and double sided tape wont stop that.) Time will tell on alloy and swelling. And on there side issues.The plastic version is starved electrolyte(my bet due to cost that alloy prismatics are the same.) Could you share where you got that info? Always question someone. Ya just might learn something new(this works both ways.) P.S. I have thick skin ;)
 

b.james

Solar Enthusiast
Could you share where you got that info?
Good on what you say . What info do you refer to . I have 6 different alloy cased 24V batteries running on security cameras and LED spotlights that I installed . Each pack is side compressed and upright . I have just put together a 48V 100Ah pack to move up to 48V in my house.
I read a uni paper on position of the cells with alloy . See if I can find it again. A few of these ready made LFP packs have them flat on shelves with a compression bar over the top.

They swell all right . Got hold of a Pro Power 50Ah drop-in that had blown . The top was off when I got it to examine . BMS was set to 3.85V ..they still do that. Too high and it blew the BMS all down one side row of mosfets. All cells were swollen somewhat but the dead cell at 0 volts was the worst . Ended up giving it the old dendrite treatment and got it charged back up to 3.3V but not much capacity in it now .Keeps my shed radio going though. I'll stick a few
Photos in and look for that uni paper for you.
 
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grizzzman

Some say "Why" and some say "Why not?"
Is it possible that the BMS failed in a way that brought the voltage up higher than 3.85 volts per cell? ( agree that 3.85 volts per cell it to high ) I would appreciate seeing that uni paper.
 

b.james

Solar Enthusiast
Is it possible that the BMS failed in a way that brought the voltage up higher than 3.85 volts per cell? ( agree that 3.85 volts per cell it to high ) I would appreciate seeing that uni paper.
Yes it always is but taken to that voltage point the cells will plate over in pure lithium and it'll clog anyway.

The truth is all prismatics are pushed tight. the plastic version needs to be clamped to avoid swelling. ( Wills electrical and double sided tape wont stop that.) Time will tell on alloy and swelling. And on there side issues.The plastic version is starved electrolyte(my bet due to cost that alloy prismatics are the same.) Could you share where you got that info? Always question someone. Ya just might learn something new(this works both ways.) P.S. I have thick skin ;)
 
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CheezWiz

No time to be an expert in anything.
Staff member
Moderator
Just another data point:

Post #8 and page 16 of the referenced pdf.

I also have the book:
DIY Lithium Batteries: How to Build Your Own Battery Packs https://smile.amazon.com/dp/0989906701/ref=cm_sw_r_cp_apa_i_wffPDbHZ3TSMB

In it, the author also states that orientation matters for prismatic cells.

I would suggest asking the specific manufacturer of a battery for their opinion. The author of that first linked PDF claims to have done that, so at that point it comes down to trusting the source.
 

b.james

Solar Enthusiast
Technology is changing mate . This one is designed for it . It sits inside a coolant bath.Plastic prismatics are a different thing judging by what I have seen pulled down.

Thats why I back it up with pictures!
This is an alloy cased prismatic!
I have many more but look closely at the third picture . The coolant is up to the black top separator and you can see some running down the side when I took the picture maybe but its outside the cell plates and is an oil and non conductive.

Geez talk about stubborn!
 
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CheezWiz

No time to be an expert in anything.
Staff member
Moderator
Technology is changing mate . This one is designed for it . It sits inside a coolant bath.Plastic prismatics are a different thing judging by what I have seen pulled down.

Thats why I back it up with pictures!
This is an alloy cased prismatic!
Don't disagree with that statement about technology but I must say that I am no chemical engineer nor am I a mechanical engineer. So cutting open cells and looking at them and determining how and why they work based on visual observation is a leap I am not willing to make personally.
That's why I would suggest anyone with an orientation question fall back on the manufacturer as the ultimate authoritative source for an answer to this.
Now getting them to answer might be the toughest part for a Chinese manufactured cell, especially if they knocked off another companies design as tends to happen these days.

That is interesting about the plastic packed cells and how they swell too. I had assumed that they were fairly size stable as I rarely see any diy builds taking that into consideration, even beyond Will's videos.
 

b.james

Solar Enthusiast
That is interesting about the plastic packed cells and how they swell too. I had assumed that they were fairly size stable as I rarely see any diy builds taking that into consideration, even beyond Will's videos.
Plastic cased prismatics will swell fairly easily and require compression of the sides . Boaties have been compressing them for 7 years that I am aware of and it is standard practice . Old Plastic prismatics had bolts through to join the separate tabs under the terminal . Rod Collins who writes for a boaties electrical page and as he said " I have a pile of swollen prismatics under my desk "

Don't know what he would be keeping them for . Maybe to throw at anyone who disagrees with him . Another Silly Old Fart (SOF)behind the times.
I even use compression on all my alloy prismatic packs on land and water although the recent pull down of a cell showed me they are remarkably solid .
 
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CheezWiz

No time to be an expert in anything.
Staff member
Moderator
Plastic cased prismatics will swell fairly easily and require compression of the sides . Boaties have been compressing them for 7 years that I am aware of and it is standard practice . Old Plastic prismatics had bolts through to join the separate tabs under the terminal . Rod Collins has a page and as he said " I have a pile of swollen prismatics under my desk "

Don't know what he would be keeping them for . Maybe to throw at anyone who disagrees with him . Another Silly Old Fart (SOF)behind the times.
I even use compression on all my alloy prismatic packs on land and water although the recent pull down of a cell showed me they are remarkably solid .
So are swollen prismatics a throw-away? LiPo packs in RC can continue to be used a bit longer, so long as they are monitored. I have noticed the EV Batts when done "right" (according to other stuff I have read) on eBay will come with plates and bolts so this is the same sort of thing then?
So far, the only prismatics I own are the metal cased ones. Is that an inherently good choice of cell?
 

b.james

Solar Enthusiast
That's why I would suggest anyone with an orientation question fall back on the manufacturer as the ultimate authoritative source for an answer to this.
Now getting them to answer might be the toughest part for a Chinese manufactured cell, especially if they knocked off another companies design as tends to happen these days.
The cell I pulled down is from Ganfeng . A large and well established manufacturer in china with worldwide connections mining Lithium . Jiangxi Ganfeng battery technology Co., ltd. is a wholly-owned subsidiary of Jiangxi Ganfeng Lithium Co.,Ltd.


Good luck trying to get an answer as to how they can be orientated. If you order by the thousand maybe.

It is important to realise the effect of funding is having on the solar market . About 6 years ago the Chinese Government gave 3 companies there the equivalent of 2 Billion $US each . That's why they are ahead in the field now . Ganfeng was one of those .

If America wants to become great again as Trump says then more funding needs to be given to our Colleges and to Solar Development Companies.
 
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b.james

Solar Enthusiast
So are swollen prismatics a throw-away? LiPo packs in RC can continue to be used a bit longer, so long as they are monitored. I have noticed the EV Batts when done "right" (according to other stuff I have read) on eBay will come with plates and bolts so this is the same sort of thing then?
So far, the only prismatics I own are the metal cased ones. Is that an inherently good choice of cell?
Swollen plastic prismatics tend to stop working pretty quick its said .LiPo packs swell doing the same thing .Prick them with a pin ,let the gas out and put a bit of tape over the hole and you can get years more . But don't keep charging them to full all the time . That's what kills them and phone,cordless and laptop batteries too .

Its wrong that LFP plates contain any ignitable material on its plates also . Thats for other technologies and allowing the gas to get out or air in does nothing to them that I have seen.

I have not had a swollen prismatic to try on because I compress them, but if you prick the vent then seal it, that would probably work also.

From the cell I pulled apart yesterday ,being an alloy cased prismatic ,they are superbly made and no amount of vibration or orientation changes will affect that.
 
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grizzzman

Some say "Why" and some say "Why not?"
I would say your analyzing of oil for cooling is spot on. "
In this study, the numerical investigation was carried to check the feasibility and
analyze the oil cooling performance for Lithium ion battery pack with mineral oil as
coolant. The study reveals that the mineral oil cooling can be a promising option to
resolve three issues related to thermal performance of Lithium ion battery for EVs.
Firstly, the bulkiness of the battery system can be reduced due to effective direct
cooling method using mineral oil. Secondly, the risk of explosion due leakage of
coolant into the battery system can be reduced due to electric non-conductive
behavior of mineral oil. Thirdly, the temperature uniformity can be maintained below
1 ºC, which is crucial to extend lifetime and ensure operating safety. In addition, the
results indicates that the pressure drop can be minimized using lesser mass flow rates
of mineral oil, which give similar cooling performance as higher mass flow rates. The
findings highlights that the cooling performance of Lithium ion pouch cell can be
enhanced using low mass flow rate of mineral oil."

This info is 3 years old.
 

electric

Solar Addict
So are swollen prismatics a throw-away? LiPo packs in RC can continue to be used a bit longer, so long as they are monitored. I have noticed the EV Batts when done "right" (according to other stuff I have read) on eBay will come with plates and bolts so this is the same sort of thing then?
So far, the only prismatics I own are the metal cased ones. Is that an inherently good choice of cell?
Yes and no, it depends. Like you said, keep an eye and them and go easy, but don't expect years of use, depends on severity of swelling and root cause of swelling.
Prismatics can be made of individual pouch cells or wound sheets, or even small cylindrical cells inside. OP mentioned K2 cells, those are made of small cylindrical cells and can go in any orientation. Pouch based blocks need more mechanical support to minimize swelling, while wound sheets need less of it. Upward orientation is recommended, side is allowed, upside down is not allowed for safety reasons, so burst valve can gas open in case of a severe fault and not leak liquid.
You can't clamp to prevent damage, it will just burst the valve instead of swelling. You should avoid the root cause, like overcharge, overdischarge, overheat, etc.
Plates and bolts in EVs are mostly to prevent shaking them lose from vibration, not an issue in solar applications, but maybe in trailers and RVs. It's just for mechanical security.
 
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