Eve battery LF280 vs LF280K cycles vs calendar ageing. Why pay extra for the (K)?
- Thread starter Maitake
- Start date
I will be extremely surprised if either of these cells last 10 years (3650 cycles) if they are used daily to 80% DOD.
The manufacturers are using extrapolations of their testing that don’t reflect actual useage to come up with a figure for cell life.
When i first saw these types of cells i was excited about the price breakthrough. A few years later and i’m already seeing enough failures to prevent me purchasing them.
Obviously time will tell, but i’d be planning for six years tops for system life if you are using cheap electronics and cells.
The manufacturers are using extrapolations of their testing that don’t reflect actual useage to come up with a figure for cell life.
When i first saw these types of cells i was excited about the price breakthrough. A few years later and i’m already seeing enough failures to prevent me purchasing them.
Obviously time will tell, but i’d be planning for six years tops for system life if you are using cheap electronics and cells.
If I recall someone stated EVE isn't even making the N version anymore so those are going to be cheaper if you find them because they are starting to be considered "old" stock or they are of greater risk of actually being used. Not sure if someone could verify.
Look at the specs seen on the EVlithium site and see if it applies to your application:
LF280 - 1C max charge / discharge LF280K - 2C max charge and discharge
Their cycle-testing methadology is also published. At least they are honest about it! Basically back-to-back (30 min rest between charge /discharge etc) simply beating the calendar-age clock for our application.
So instead of trying to predict the future, you can make some sort of evaluation as to how they are spec'ed and tested NOW.
HONEST. I like that. But you can see if one is just "shopping the cycles" and not taking into account the true nature of their own application, this can only serve as a "guide". YMMV.
LF280 - 1C max charge / discharge LF280K - 2C max charge and discharge
EVE LF280K 3.2V 280Ah LiFePO4 Battery Cell
EVE Brand New Grade A LF280K 3.2 V 280ah LiFePO4 Battery Cell With 6000 life cycles and 2C discharge rate.
www.evlithium.com
Their cycle-testing methadology is also published. At least they are honest about it! Basically back-to-back (30 min rest between charge /discharge etc) simply beating the calendar-age clock for our application.
So instead of trying to predict the future, you can make some sort of evaluation as to how they are spec'ed and tested NOW.
HONEST. I like that. But you can see if one is just "shopping the cycles" and not taking into account the true nature of their own application, this can only serve as a "guide". YMMV.
curiouscarbon
Science Penguin
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- Jun 29, 2020
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EVE are the cheap cells?
What do you recommend.
Two years in, about to go into the third year. No issues yet.
Winston / Sinopoly / CALB CA / GBS are the only easily available cells i have seen last over 10 years in service.
Of course the newer cells (EVE / CATL / Lishen / Ganfeng etc) haven’t been in existence for 10 years, so for a more complete picture we will have to wait another 5 years or so. If the majority of batteries like Upnorthandpersonal’s are still going strong when they turn 7, then i will revise my opinion.
WOLF-GANG
New Member
Why not ? We have winston cells from CZ warehouse that were delivered in 2014. Still about 94% of capacity and just 2 years to go to proof if that is right or not.
II bet they will over deliver a lot above 80% in 2 years and I am sure they will even last a lot longer then.
WOLF-GANG
New Member
Be carefull cause there are a lot more than just LF280 cause EVE had also sold LF280M if I remember right and people quite often to forget about the last letter which is important cause only that determines size and chemistry. The LF280 , LF280M and LF280K come in different shapes / sizes, one ist a bit bigger than the others cause it has caused a lot of headache once we realized the difference after arrival of the second batch cause the bus bars were no longer fitting.Look at the specs seen on the EVlithium site and see if it applies to your application:
LF280 - 1C max charge / discharge LF280K - 2C max charge and discharge
EVE LF280K 3.2V 280Ah LiFePO4 Battery Cell
EVE Brand New Grade A LF280K 3.2 V 280ah LiFePO4 Battery Cell With 6000 life cycles and 2C discharge rate.www.evlithium.com
Their cycle-testing methadology is also published. At least they are honest about it! Basically back-to-back (30 min rest between charge /discharge etc) simply beating the calendar-age clock for our application.
So instead of trying to predict the future, you can make some sort of evaluation as to how they are spec'ed and tested NOW.
HONEST. I like that. But you can see if one is just "shopping the cycles" and not taking into account the true nature of their own application, this can only serve as a "guide". YMMV.
And finally the LF280K has also a far wider gap between the terminals than the others, so you can not easily pair a LF280K cell with LF280 cell due to different hight and position of the terminals. I am sure that they had a least 3 different types of LF280 made so far, which all sound the same, but were different in size and so on.
WOLF-GANG
New Member
No, not at all cause you misunderstood the important points cause calendar aging referrs also usually to having 80% of initial capacity.
The warranty or promise they gave is that you will still have 80% either till 3500 (full) cycles or 10 years.
For the LF280K you pay a bit of premium cause it offers 6000 cycles compared to the 3500 from the previous one. Might be a huge advantage or not depending on your battery cycles cause 10 year 300 charging cycles could mean 3000 full cycles done and still 80% or you charge them twice a day and will use a lot more cyclces.
BUT BE CAREFULL AND READ ALL THE SPECS instead of judging without care cause
EVE has changed the test method from the previous LF280 generation to the LF280K cell by lowering the discharge rate to half of the previous one, from 1 C to 0,5 C which mean 280 A discharge to 140 A discharge which will lead to better results just by changing the method.
They do only release the 3500 cycles for the old and 6000 for the new one but they did not tell us how many cycles the usual LF280 cell would gain simply due to a 0,5 C discharge . Imagine you would get 4500 cycles just due to half discharge rate of 140A instead of 180A
Battery cells are the most expensive part so take your time if you compare cells cause it needs a lot of attention if they do change specifications from one generation to the other. 11 pages each generation and even within the LF280K modell they have changed things already.
Winston cells are vastly different to EVE cells.
WOLF-GANG
New Member
Of cause they are vastly different but these were the first LiFePo you could get back then and they still do a great job but will be sold when they reached the 10 years.
