kinda forgetful 
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In a way, shows how good they are, the new tattu lipos have a safe storage discharge system in case you forget
Also if that image is difficult to read they basically told me they cannot disclose their testing specifications to reach their “Longer Cycle Life 600+”
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But…the link in that image is to a Turnigy pack?
Retailers/distributors often do not have that kind of tech data available. Best to request it from the pack assemblers themselves.
It shows that they have pack with lots of features, not that the pack was well made, has been spec’d properly, or that they use good cells. 
Tattu packs are loved by many but we can’t assume that all aspects of a pack’s performance and safety are great based on the number of features a pack has.
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Yeah the photo is from the Turnigy customer service regarding a graphene pack, by Tattu it is I meant I’m likely gonna pick up a Tattu lipo pack.
Any idea of who to contact to grab those specs?
I feel if they claim 600+ cycles they should at least have some basic info on how they got those numbers.
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That was Turnigy’s customer service? It looked like Hobby King. Or is Hobby King actually Turnigy’s store?
As I mentioned it’s best to go to the pack assemblers themselves for tech info on the packs. Not sure if Turnigy has a web site though. Perhaps Alibaba or AliExpress?
Hopefully Tattu’s web site has a Contact Us link.
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Hobbyking is Turnigys customer service I believe. I’ll give an update if I get any more info on the cycle life of the Graphenes
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I’d be very interested in seeing that!
See if you can get them to give you the contact info for one of their engineers.
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I found some information about what Tattu expects from their batteries from their blog, and they seem realistic. Not particularly descriptive or sciency, but more specific than Turnigy’s response 
. They also seem slightly more conservative in their low voltage cutoffs in their blog, citing 3.5-3.65v as cutoff voltage, which is no doubt better for the battery as well.
Q: How many cycles can I expect from my battery?
A: Normally, Gens Ace & Tattu Li-Po batteries are good for about 200 cycles at full capacity. After that, the capacity will be reduced until about 400 cycles. Of course, this depends on how the battery was treated during its life. If you discharge it at full capacity or never balance the pack, your battery will usually only last 30-50 cycles. Always measure your amp draw and choose a battery that is rated for discharge at least 25% more than your recorded discharge amps. (If you are pulling 20 amps – you should use a 25 amp continuous battery)
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Thanks for posting that!
I never cease to be amazed at just how delicate the typical pouch LCO-chemistry Li-Ion (LiPo) cell is. That is incredibly poor cycle life performance vs a standard cylindrical Li-Ion cell. The price we pay (in cycle life) for low internal resistance is very high.
Only 50 full cycles until end-of life if discharged to, I assume, about 3.0V? You also mention 200 cycles if fully discharged.
I’m wondering what the criteria for end-of-life is? Do they use the common 20% capacity loss spec or could it be worse?
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Aluminum ion batteries can’t come soon enough. With a trivalent charge carrier, amps for days. Plus all the other benefits of using aluminum (MUCH more abundant, massive recycling and manufacturing infrastructure already in place)
The low internal resistance comes from I am guessing the extremely small separation distance between electrodes, hence there is less “life” so to speak to whittle away as it ages.
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A thinner separator could indeed reduce the IR. The much wider tabs used for high power pouch cells eliminates a big performance bottleneck too. A standard cylindrical cell has tiny tabs from the spiral roll to the top and bottom of the can that offer considerably more resistance than the wide tabs in pouch cells.
Maybe high performance pouch cells have thicker current collectors (foils) too? Possibly additional conductive additives in the anode and cathode active materials too, though that reduces capacity.
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Yeah, more surface area for the reaction to occur. If I’m not mistaken, battery aging occurs due to formation of dendrites and plating of the electrodes. With more surface area, plating occurs at a much faster rate.
Lead-acid chemistries age the same way, plating of the electrode with inert materials.
Wish someone would invest in aluminum ion chemistry research :(.
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I think the tradeoff to endurance is in stupidly high current output. The 14Ah Tattu ones are rated to 25C, which is 350A continuous. I also have smaller batteries that are 65C continous/130C burst, which is far better than what cylindrical cells can output for the same size.
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There are several aging mechanisms…
Loss of lithium, either by plating or by electrolyte decomposition and increasing SEI layer thickness, is definitely one.
Research is going on but Al-Ion still has cycle life and other issues compared to other more mature cell technologies. It will probably, IMO, end up being used only in certain niche applications. Sounds like you’re a believer in the potential for Al-Ion chemistry cells though!
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If I have two 6374 75amp motors and a battery capable of 350a plus a flipsky 6.6, what should I set the battery current at? I know my xt90s can only take so much should I have it around 60a or like 100a? Also what should I do as my battery max regen?
Agreed. The low internal resistance allows for lots of current with less heating. But that ages them even faster as it encourages lithium plating and other things to occur.
C-ratings are spectacularly exaggerated IMO…essentially useless. They’re often higher than the fusing current (melting) spec for the wiring the pack uses! Definitely higher than what the connectors can handle.
What use is a spec like that? Oh…wait…marketing one-upmanship. 
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Someone more knowledgeable than me will have a better answer, but 100A might be ok. The board isn’t drawing 100A all the time, and depending on how you ride, the times you do reach 100A should be transient and won’t heat it up too much before it drops back down. You can try it, and if you find it overheating, drop it back down. Similarly with battery regen, the spikes from braking will momentarily exceed the rated charge amps, but it should drop down to safe levels reasonably quickly unless you’re going really fast and braking hard.