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I received a response from CALB in regards tot their CA cell and orientation.

"The reason why our cell can't mounted horizontally lies in the structure of the cell. Our rectangle cell choose lamination structure and lay horizonally would result in short circuit. If you insist on achieve this, you can choose pouch cell or round cell.

This is completely different than a response I got from them a while ago... the response I got was that they could be mounted horizontally without a problem. Only upside down is 'forbidden'.
 

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This is completely different than a response I got from them a while ago... the response I got was that they could be mounted horizontally without a problem. Only upside down is 'forbidden'.
This is what I am not sure of, I was very specific and worded the question to try and minimise confusion. The answer is technical and I double checked it with them. The person who I spoke to was the Europe Department, Sales Representative but she was based in China.

Leigh
 

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This is what I am not sure of, I was very specific and worded the question to try and minimise confusion. The answer is technical and I double checked it with them. The person who I spoke to was the Europe Department, Sales Representative but she was based in China.

Leigh
The answer you got is almost meaningless and contradictory to reality. If the cells will short if mounted on their side then they have no place in a high vibration high G force environment like a car. They would short when you go around a corner or when you are braking. The people who answered your question are not engineers and almost certainly have nothing to do with manufacture of the cells they are marketing. Manufacturing in China does not work like most other places where the factory is owned by the company that you buy the product from. Calb is a trading company that gets the product from one or more factories but most likely does not have any ownership of those factories. Asking technical questions of the marketing people would be like walking into Walmart and asking a checkout person about the color temperature of one of the LED bulbs they sell. Ok that is a stretch but not as far from reality as you might think.

People have been using prismatic cells positioned on their sides for several years without any issues. The particular brand is probably of little importance. The internal construction of a pouch cell is identical to a Prismatic cell for the purposes we are discussing.

If you have the cells why not take one and lay it on its side and cycle it a few times to assure yourself there won't be any issues. This would be more productive than trying to get answers from the marketing types through language barriers.
 

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I do believe that a tray mounted to the bottom of the body would have been the simplest to implement for a modified vehicle. I just don't want to fill my trunk and hood with cells, causes problems and looks crap.

Are there any good cylindrical cells on the market that are of a similar cost and spec to the CALB CA cells?
The GBS third gen cells would be ideal for mounting in a pan under the floor. Unfortunately they are available only in 200AH configuration. 36 of these with an AC-50 would be a really nice arrangement for a 2500 lb. or less car.

There are no cylindrical cells that are large enough to not be a real pain to wire up. And the available ones are quite a lot more expensive when you make a full size pack.
 

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The GBS third gen cells would be ideal for mounting in a pan under the floor. Unfortunately they are available only in 200AH configuration. 36 of these with an AC-50 would be a really nice arrangement for a 2500 lb. or less car.

There are no cylindrical cells that are large enough to not be a real pain to wire up. And the available ones are quite a lot more expensive when you make a full size pack.
Thanks for this dougingraham, i will use this. I am also going to push CALB to explain why they believe that short circuit is possible (I'd just like to get them to prove it now).

Leigh.
 

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Thanks for this dougingraham, i will use this. I am also going to push CALB to explain why they believe that short circuit is possible (I'd just like to get them to prove it now).

Leigh.
If you happen to squeeze that information out of them be sure to publish it.
 

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I got a response from CALB again:

Q) Thank you for your response, you said that the CALB CA cell would short circuit if placed on the side, but I have had a technical team tell me that the CA cell is several pouch cells mounted together in a plastic enclosure.

A) As I mentioned in my last email, our cell is laminated structure. I attached a pouch cell picture for your reference.

Q) What is the difference between the pouch cell and the CA cell?
A) Pouch cell is soft package cell, CA cell belong to rectangle cell. (rectangle cell, cylindrical cell and pouch cell are three main lithium batteries).

Q) Where would the short circuit occur?
A) We suggest the battery is stand up, if it's flat on the floor, electrolyte will leak and result in short circuit.

Q) If the CA cell was placed horizontally would there any other issues (such as electrolyte leakage)?
A) That's the main reason, the possibility of electrolyte leakage increased if placed horizontally.

Q) Is CALB developing a pouch cell to use horizontally? would there be other issues?
A) Our pouch cell is under R & D now.

From these answers I believe the main reason why they cannot lay horizontally are the connection tabs at the top of the cell, any electrolyte leakage shorting the circuit and this I believe is what they are mentioning.

If this is the case; could we just place the cell on a 80 degree angle instead of 90? This would mean the cell is flat(ish) and would keep the electrolyte at the bottom of the cell.

The only scenario where this may be an issue is if the car is parked on the sidewalk (curb) and the 10 degree angle is negated.

Thoughts?
 

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Q) Where would the short circuit occur?
A) We suggest the battery is stand up, if it's flat on the floor, electrolyte will leak and result in short circuit.

Q) If the CA cell was placed horizontally would there any other issues (such as electrolyte leakage)?
A) That's the main reason, the possibility of electrolyte leakage increased if placed horizontally.
Sorry for digging up this old thread, but these replies from manufacturer look insane... :eek:
  1. An automotive battery has mount orientation contraints? It is not a static battery, it must tolerate accelerations and vibrations!
  2. And how is the electrolite supposed to "cause shortcircuits"? It MUST "shortcircuit" all plates, isn't it there for this reason? :confused:
  3. Additionally, I don't think prismatic cells actually have same assembly type of lead batteries, where you have multiple plates soaked in electrolite; you instead have multiple sealed cells made up of three layers: electrode, elecrolite, electrode.

From photos posted above I can't understand if there is actually a floating electrolite, removed to take pictures, or if it wasn't there from the beginning...
 

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My understanding is that the individual sealed pouch cells are swimming in electrolyte, which fills the handsome plastic case that encloses the pouch cell assembly and hence fills up the spaces between pouches. Presumably, the electrolyte is being used primarily for heat transfer purposes. That's a guess on my part.

There's a relief valve located between the terminals. If the cell is mounted upright, the relief valve will vent headspace vapour. If the cell is mounted in either horizontal orientation, the relief valve will vent electrolyte. That will eventually deplete the space between the cells of electrolyte, defeating whatever purpose it's there fore.

What they're talking about with respect to short circuiting, I have no idea.
 

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Q) Where would the short circuit occur?
A) We suggest the battery is stand up, if it's flat on the floor, electrolyte will leak and result in short circuit....
Yes, I realize this is an old thread but someone had to dig it up anyway so here is what the Chinglish above is supposed to mean: 1) electrolyte is conductive; 2) placing a prismatic cell flat on its wide side increases the chances of electrolyte *leaking* from the cell; 3) leaked electrolyte will create a conductive pathway outside of the cell which could then cause a short circuit.

...Presumably, the electrolyte is being used primarily for heat transfer purposes. That's a guess on my part.
Sigh... no, the electrolyte is there to conduct current as well as electrically charged ions between the cell plates (anode and cathode).
 

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My understanding is that the individual sealed pouch cells are swimming in electrolyte, which fills the handsome plastic case that encloses the pouch cell assembly and hence fills up the spaces between pouches.
What they're talking about with respect to short circuiting, I have no idea.
No, the prismatic cells we use like the CALB SE do not have sealed pouches within the plastic case. They are wrapped but not in sealed pouches. They are also not SWIMMING in electrolyte. There is enough to saturate them and there is a little that rests on the bottom that does nothing but keep the environment damp. The bulk of the electrolyte is within the matrix of the cells. In other words the carbon is soaked in electrolyte and because the particles are so small the electrolyte stays in place due to capillary action.

The Hi-Power Prismatic Cells do not have a top VENT. That cap is just a cap with an o-ring to seal it.

Maybe the others do but if enough pressure were to be created Im sure it could vent around that o-ring seal. Now the interesting thing is that the terminals around the top are not actually sealed. They are tight against the terminal as it comes through the top.

If you laid the cell on its side there would not be enough free electrolyte to even come close to touching the terminals. If it were laid flat the same would apply. But if you mounted it upside down the electrolyte could possibly leak around the terminals.

The 100ah Cell contains two wrapped 50ah cells.

http://onegreenev.blogspot.com/p/prismatic-dissection.html
 
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