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OK to store pouch cells on their sides?

softdown

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Bought 4 of the A123 24V pouch batteries from Big Battery. Three have been delivered (how lovely are split deliveries?).

I'm a prepper of no intention of getting chipped so I can buy in the market place. These batteries will be stored several years - until the LA batteries in use decide negatively on the ultimate futility of life.

The commercial fridge used for storage has "permanent" racking. Was able to store two upright on the bottom. The others will have to be stored on their sides. Is this acceptable?

OK to store pouch cells on their sides?
 
Big Battery rep said any side is OK except for side with voltage read out and SB150 connector. That is a nice feature.
 
Bought 4 of the A123 24V pouch batteries from Big Battery. Three have been delivered (how lovely are split deliveries?).

I'm a prepper of no intention of getting chipped so I can buy in the market place. These batteries will be stored several years - until the LA batteries in use decide negatively on the ultimate futility of life.

The commercial fridge used for storage has "permanent" racking. Was able to store two upright on the bottom. The others will have to be stored on their sides. Is this acceptable?

OK to store pouch cells on their sides?
Everyone that I have talked with has said on its long side is ok. The thin side preferably not, unless the terminals are upright. But then that would be the bottom side.
 
I believe the only wrong way to store them is with the cell vents facing down. That is likely what they are warning you about using the SB150 connector as a landmark.

You could always pop the cover off to confirm.
 
The main thing with long term storage of any lithium battery is not what direction it is facing, but what charge level it is at.

You want to keep the cells between 30% and 60% state of charge. If they get too low, they will fail. And a high state of charge will degrade them and cause puffing and loss of capacity. I would say keep them above freezing temp with a constant voltage of about 3 volts per cell and they should be fine for many years. If you can't keep a low current constant voltage, then check the voltage every few months to make sure they don't self discharge too much. Good cells will hold voltage for years, but if there is a BMS etc. there could be some leakage current that could drag them down over time. Don't ever let them go below 2 volts per cell.
 
The main thing with long term storage of any lithium battery is not what direction it is facing, but what charge level it is at.

You want to keep the cells between 30% and 60% state of charge. If they get too low, they will fail. And a high state of charge will degrade them and cause puffing and loss of capacity. I would say keep them above freezing temp with a constant voltage of about 3 volts per cell and they should be fine for many years. If you can't keep a low current constant voltage, then check the voltage every few months to make sure they don't self discharge too much. Good cells will hold voltage for years, but if there is a BMS etc. there could be some leakage current that could drag them down over time. Don't ever let them go below 2 volts per cell.
I think you meant 2.5 volts per cell.
And yes, a BMS etc will cause a trickle drain. I forgot that one :)
 
I just finished reading thi and I thought to share it.
"It was once thought prismatic cells could be operated in more or less any position as they do not really contain free liquid. Nowadays manufacturers are a lot more prescriptive with installation position. In most instances, the only acceptable position is upright, vent cap and terminals on top (Sinopoly, Winston). Sometimes it may be acceptable to mount them on edge, with the terminals on the side (CALB). This may vary not only between manufacturers, but also between cell models, so seeking specific guidance is a sensible step if an odd installation position is being considered.
When questioned, Sinopoly indicated that installing the cell in any other position than upright would cause some of the plates to run dry after a while, damaging it. Installing them flat on their side is out of the question in all cases."

Found it here. http://nordkyndesign.com/assembling-a-lithium-iron-phosphate-marine-house-bank/

This changes everything I think.
 
The original post and the title is about "pouch cells". I have seen factory designed systems that position pouch cells in many different positions. The only position I don't see often is the tabs facing down. Most have the flat dimension standing vertical with the tabs either up or to the sides. Only a few have the cell laying flat. With my Chevy Bolts LG pouch cells, I have them mounted in the same way as they are in the car. The pouches are all vertical with the tabs on both ends on the sides. In a car they have to deal with all kinds of shock and vibrations. They will live a much easier life sitting in my garage.

The A123 pouch cells do appear to have very similar construction to the LG cells. They are nothing like CALB, Winston, or Sinopoly prizmatic cells. Here is a document I found on A123 cell pack design.


And ES, A123 cells can be run down to 2.0 volts as a minimum safe voltage. All of the diagrams showing the cells has the oriented with the tabs up. The cells also do have an intentional weak point that will burst to vent the cell in case of excessive pressure. They also show this as facing up. It is typically next to one of the tabs.

Under "Storage Specifications", it says "Store cells in a dry location. To minimize any adverse affects on battery performance it is recommended that the cells be kept at room temperature ( 25C +/- 5C ). Elevated temperatures can result in shortened cell life."

It does not mention orientation. The fact the cell orientation is not stressed in the entire document seems to imply it is not critical. But it is interesting to note that every diagram has them shown with the tabs facing up.
 
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