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Cylindrical vs Prismatic Cells

brclark82

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Sep 16, 2021
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I just saw a short video from Battleborn stating they use cylindrical cells vs prismatic cells. The benefit being they can be fully discharged 100% without affecting life of their batteries. They say prismatic cells can advertise 2000 cycles at 80% discharge but in reality is closer to 900 cycles at 100% discharge. They say Battleborns with last 3000-5000 cycles at 100% discharge.

I am always a little skeptical of companies telling me why they’re better so I would like to know this groups thoughts…
 
. They say Battleborns with last 3000-5000 cycles at 100% discharge
100% discharge may mean down to their BMS cuttoff @20% ??
Probably because they are based in the USA they need to be more honest with their stated battery capacities verses cycles and have their batteries perform to what they are rated.... 100ahr battery needs to supply 100ahr, So they use 120ah of cells. A 100% discharge(100ahrs) down to bms cut off still leaves 20% charge in the batteries for the cycles stated.

"I am always a little skeptical of companies telling me why they’re better "....yes, always read the fine print
 
How much are bus bars going to cost connecting so many small cells? I think there's some costs you're not factoring in building a pack with the small cells. I would probably go with prismatic simply because they're so easy to deal with. I thought prismatic cells advertised like eve 100% discharge for up to 2500 or 3,000 cycles and still keep 80% capacity. I don't understand why anybody wouldn't push these cells to their Max.
 
How much are bus bars going to cost connecting so many small cells? I think there's some costs you're not factoring in building a pack with the small cells. I would probably go with prismatic simply because they're so easy to deal with. I thought prismatic cells advertised like eve 100% discharge for up to 2500 or 3,000 cycles and still keep 80% capacity. I don't understand why anybody wouldn't push these cells to their Max.
Eve advertises 3500 cycles using 80% of the soc, the prismatic cells last longer (on average double) than the cylindrical ones, the advantages of the cylindrical ones are summarized in the possible installation position that does not create any problem
 
Eve advertises 3500 cycles using 80% of the soc, the prismatic cells last longer (on average double) than the cylindrical ones, the advantages of the cylindrical ones are summarized in the possible installation position that does not create any problem
On the LF280N it is 3500 cycles using 100%, here is the spec from EVE.
 

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They are 100% as well, 2.5 volt cut off.
yes, but there are 6000 cycles, the point is: respect the ideal temperature conditions, which is definitely impossible when installing in particular situations such as RV vehicles. Therefore: respect the 80% soc and try to make a fixation as close to the famous 300kgf to extend the life of these batteries
 
Most primatic LFP cells are thick electrode design. Thick electrode means the thickness of graphite negative electrode and positve LFP electrode are 110 to 150 um thick. This yields the most AH capacity per unit volume and weight but cell suffers from ion starvation above about 0.5CA cell current caused by the thick electrodes. This increases terminal voltage slump and internal cell heating accelerates above 0.5 CA cell current.

Most cyclindical cells are made with thinner electrodes design in 50 um to 100 um thickness. This means more layers are required for same AH rating as capacity is dependent on amount of graphite and LFP material. More layers mean more copper foil, aluminum foil, and electrolyte. This costs more, takes up volume, and adds weight. Extra metal foil benefits are lower contact resistance and better heat dissipation. Cylindrical cell with thin electrode allow high peak cell current with onset of electrode layer ion starvation at a much higher current. This also helps at cold temps where ion migration rate slows down.

Prismatic cells with thick electrode design.
+ Most capacity per unit volume and weight
+ lowest cost
- lower peak discharge current
- less ability to dissipate internal cell heating

Cylindrical cells with thin to moderate electrode design
+ higher peak current discharge rate
+ ability to dissipate internal heating
+ better cold temp performance
- AH per volume/weight
- higher cost

There is really no difference in damaging effects of, depth of discharge between thin or thick electrode designs. Both will grow metal dendrites if left for moderate time below 1.0 vdc and both will have severe electrolyte decomposition if discharged below about 0.1 vdc or charged above 4.3 vdc.
 
I wanted to thank you for the detailed response. I wasn't aware of some of those differences.

I personally went with lifepo4 32650 cells because I got a good deal at the time and the one thing you really don't have to worry about with cylindrical cells is dealing with any type of compression.

In my scenario, I figure in ten years I could be left with an 8s system that has one bad 280ah cell OR I could have five failed 32650 and twenty 32650 still working fine. One bad 280ah cell could screw up my entire system and a new one would perhaps take days to arrive and then it would be a different capacity and lifecycle than the other cells in series. The 32650 I could rearrange as needed with a bit of work.

I don't hear people mentioning these benefits all that much, and certainly it is easier to just wire up 8 big cells vs hundreds of 32650 cells.

It didn't hurt that battleborn and others use cylindrical cells and have decent warranties.
 
I just saw a short video from Battleborn stating they use cylindrical cells vs prismatic cells. The benefit being they can be fully discharged 100% without affecting life of their batteries. They say prismatic cells can advertise 2000 cycles at 80% discharge but in reality is closer to 900 cycles at 100% discharge. They say Battleborns with last 3000-5000 cycles at 100% discharge.

I am always a little skeptical of companies telling me why they’re better so I would like to know this groups thoughts…

I call BS on their claims. The format of the cell has nothing to do with the longevity.. well.. almost nothing.

Cylindrical cells do have one minor advantage, but its so minor as to be insignificant, and it only applies in certain applications.. because of the cylindrical shape, they are just ever so slightly better at dissipating heat.

Beyond that, cylindrical cells tend to blow up because of the way they can build and retain pressure, while pouch cells tend to flame out with less force.

These companies make all kinds of claims to boost sales..
 
i’m kind of reopening a fairly old thread. But recently I discovered an article talking about the advantages of cylindrical cell versus prismatic cells. I have particular interest in this subject since completely by chance I ended up with a set of four batteries that have cylindrical cells inside. They make up a 48 V battery that I use in my camper.

Cylindrical cells can be placed in any orientation with no adverse effects

Cylindrical cells can be charged at colder temperatures than prismatic cells.

Cylindrical cells have a higher c rate than prismatic cells.

Cylindrical cells have better cycle life at full depth of discharge than prismatic.

Cylindrical cells have more cycle life than prismatic cells

Cylindrical cells stay cooler than prismatic cells.

I’m wondering if any of these claims are true and to what extent. Is there any proof pro or con.
 
Solamante la prima è vera, le cilindriche possono lavorare in qualsiasi posizione, stop per il resto meglio le prismatiche
 
Solamante la prima è vera, le cilindriche possono lavorare in qualsiasi posizione, stop per il resto meglio le prismatiche
After google translate.
Only the first is true, the cylindrical can work in any position, otherwise the prismatic ones stop better.


scusa la mia traduzione è così scarsa che ho dovuto usare Google Translate L'inglese è la mia prima lingua e non parlo molto bene.
 
yes the cylindrical ones have a higher internal resistance, fewer life cycles, the discharge in terms of C is not very different from that of the more performing prismatics and the charging temperature depends on the chemistry so it is the same. also cylindrical are often made by small companies that do not have quality control such as companies such as Caltl, Eve, rept, Calb etc.
 
yes the cylindrical ones have a higher internal resistance, fewer life cycles, the discharge in terms of C is not very different from that of the more performing prismatics and the charging temperature depends on the chemistry so it is the same. also cylindrical are often made by small companies that do not have quality control such as companies such as Caltl, Eve, rept, Calb etc.
I have been trying to find documentation for the expected life span compared with each other and so far I have not found where they have been tested against each other. Battleborn ( one of the best known lithium batteries built in the USA) uses cylindrical cells in there batteries with excellent results but the cells they use are probably better grade than the batteries I have and they do extensive testing and balancing before assembling the batteries. The internal resistance of the batteries I have can’t be very high as they charge at 40 amps until they have around 6 amp hours to go and then gradually taper back until full.
 
I have been trying to find documentation for the expected life span compared with each other and so far I have not found where they have been tested against each other. Battleborn ( one of the best known lithium batteries built in the USA) uses cylindrical cells in there batteries with excellent results but the cells they use are probably better grade than the batteries I have and they do extensive testing and balancing before assembling the batteries. The internal resistance of the batteries I have can’t be very high as they charge at 40 amps until they have around 6 amp hours to go and then gradually taper back until full.
the smaller batteries are as Ah the greater the internal resistance
 
the smaller batteries are as Ah the greater the internal resistance
The batteries I have are 12 volt they are made with multiple packs of cylindrical cells in parallel to create 100 amp hours four of these packs I put in series to create to 12v. I’m attempting to compare the performance of them to a prismatic cell based 100ah battery.
 
Perché le celle cilindriche più grandi del 6AH, se assemblate in una batteria da 48V 100Ah, pensi che il gran numero di celle cilindriche nel processo produttivo avrà sicuramente molti punti di appoggio e sistema di contattori all'interno della batteria, aumentando così la complessità e peso della batteria! E una cellula difettosa causerà una reazione a catena! Se il consumatore non considera la sicurezza e l'affidabilità, ma solo il prezzo, allora anche questi deve farglielo sapere.
Non è vero dipende da come sono assemblate, conosco aziende che forniscono ogni singola cella di fusibile che escludere solo quella danneggiata
 
Non è vero dipende da come sono assemblate, conosco aziende che forniscono ogni singola cella di fusibile che escludere solo quella danneggiat
If all issues related to quality are the same what are the differences in performance and longevity between the two styles of batteries. For clarification I am referring to lithium iron phosphate not lithium ion.
 
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