# How does the discharge curves of Eneloop Pros compare to standard AA & AAA Eneloops?



## theilluminati (Sep 14, 2014)

*How does the discharge curves of Eneloop Pros compare to standard AA & AAA Eneloops?*

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Sorry. I was not able to find this on Google, since I don't know how do you refer to 'standard', 'normal' or 'basic' Eneloops.</p>
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http://panasonic.net/energy/battery/eneloop/lineup/</p>
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This graph mentions only 70% capcity after 5 years for the basic version, 85% capacity after a year for the normal version; not a basic I can use for comparison. AA & AAA; both are interesting.</p>
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I am not likely to charge them even 500 times in their useful life, let alone 2000 times; so it's a question if they last for 20 years (higher performance) or 100 years (lower performance).</p>
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Related question: *should I opt for the Pro for my flashlights and oral irrigator*? I find normal Eneloops not too strong in the latter.</p>
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Interestingly, the picture for the basic version doe not show flashlights:</p>
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http://ecx.images-amazon.com/images/I/716iWuaTrDL._SL1500_.jpg</p>
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The Pro does:</p>
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http://ecx.images-amazon.com/images/I/51B48HxliAL.jpg</p>
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Most of you seem to use here standard versions, though.</p>
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Edit: image inserts do not work?</p>
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Forum engine seems broken from here.</p>


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## HKJ (Sep 14, 2014)

*Re: How does the discharge curves of Eneloop Pros compare to standard AA & AAA Eneloo*

Start here for discharge curves: http://lygte-info.dk/review/batteries2012/CommonAAcomparator.php


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## theilluminati (Nov 19, 2014)

*Re: How does the discharge curves of Eneloop Pros compare to standard AA & AAA Eneloo*

Your site is excellent; just what I was looking for; thank you!

Btw. what is a quick way to pick up some basic knowledge on how to interpret the data; to determine if I better use the high power/medium/low power version of - say - the Eneloop family for various gadgets?


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## Rosoku Chikara (Nov 19, 2014)

*Re: How does the discharge curves of Eneloop Pros compare to standard AA & AAA Eneloo*



theilluminati said:


> Your site is excellent; just what I was looking for; thank you!
> 
> Btw. what is a quick way to pick up some basic knowledge on how to interpret the data; to determine if I better use the high power/medium/low power version of - say - the Eneloop family for various gadgets?



In theory, you would need to know how many mA are being used by each of your "various gadgets." Usually, this is easy enough to determine using a multi-meter, but you can get a general idea from how long your batteries usually last in each application. In other words, batteries in clocks and remote controls will tend to last a very long time before they go dead. Whereas, batteries in devices that use electric motors (pepper mills, portable fans, etc.) tend not to last long at all. Flashlights can vary considerably depending on how they are designed and how bright they are.

So, as a fellow novice, I would suggest that you compare some low mA curves, med mA curves and high mA curves for each cell type you wish to compare. Just be sure to use the same mA level(s) for all the cells you look at. I believe that HKJ's comparator shows a low 0.1A (100mA) and a relatively high 2.0A (2000mA) curve by default. I believe that most, if not all, of your gadgets will likely fall within that range.

Also note that, in most cases, what you are looking for is the point where voltage begins its dramatic decrease. With two cells of very similar design and identical chemistry such as Eneloop and Eneloop Pro the shape of this curve is very similar, but only "further away" with the higher capacity "Pro" cells. You should notice much different curves when comparing other cell types.

Personally, I have elected to go with all "Pro" cells. I prefer their increased capacity, and the price difference in my market is not so dramatic. People in other markets sometimes find the "Pro" cells to be prohibitively expensive.


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## MidnightDistortions (Nov 19, 2014)

*Re: How does the discharge curves of Eneloop Pros compare to standard AA & AAA Eneloo*

I go by usage. The Pros are good for emergency situations where you need that extra 17-20% of battery life and are more beneficial in high drain devices. If i'm using a device regularly that requires me to recharge often i find that the regular Eneloops work the best because you got more cycles in it's lifespan. Even if you only recharge the Pros once a week you'd still get 10 years of usage. If you don't use the batteries often i'd go with the Pro Eneloops. I don't know how long the basic Eneloops last if you don't use up all their cycles and since they only have been on the market for 9 years it's too soon to tell if the batteries are built to last past several decades.


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## Viking (Nov 19, 2014)

*Re: How does the discharge curves of Eneloop Pros compare to standard AA & AAA Eneloo*

Hi MidnightDistortions

A nimh cell will not last several decades unless you really appreciate the term ”crap cells” 

Batteries deteriorates both due to cycles and age. What you concider a dead battery also very much depends on how ”picky” you are. The factories designates a battery for dead when capacity has fallen to 60 percent or less from the starting point. Personally I discard them when they are down to about 80 percent. 

According to Energizer the life expectancy for ordinary nimh cells regardless of cycles is limited to maximum 5 years before this happens. Typical life expectancy is between 2 - 5 years.

I believe LSD cells in most cases has proven to be more long term healthy than ordinary nimh , so I personally estimates approximately 10 years of use. However some have discarded them sooner than that , both for regularly eneloops and pro versions , especially the later. It all comes down to use and performance requirements.


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## WalkIntoTheLight (Nov 20, 2014)

*Re: How does the discharge curves of Eneloop Pros compare to standard AA & AAA Eneloo*

I've got 14 year old NiMH cells (obviously not LSD) that are still going fine. They aren't any use for high-drain applications, but are fine for low drain uses. They don't seem to self-discharge much faster now than when they were new. Capacity is down a bit, but still very acceptable.

I think they biggest factor in how long NiMH cells will last is their initial capacity. I've had very bad experiences with high capacity cells. They work great for awhile, but within a year or two they're useless. I think that the design of high capacity cells gives them short life spans. Thin walls separating the electrolyte or something? Whatever the case, stick with lower capacity and you'll probably have long-lived batteries. LSD batteries are all lower capacity, so I suspect they'll last a long time. My 8+ year old Eneloops still work like new, and have the same capacity (at a 2A discharge) as my newer Eneloops.

When they start to show their age, I'll use them in low-drain applications. As long as they don't start to self-discharge (I'm not sure if they will or not), remote controls and clocks are a great use for old Eneloops.


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## Viking (Nov 20, 2014)

*Re: How does the discharge curves of Eneloop Pros compare to standard AA & AAA Eneloo*

Hi WalkIntoTheLight

I agree the initial capacity has a lot to say about the longevity of the cell. My experiences with high capacity cells isn't that good either. But that's probably one of the reasons Energizer states 5 years as a maximum life expectancy. For high capacity cells this would probably be less.

The stated Energizer life expectancy for nimh cells shouldn't be taken as the absolute truth. I wouldn't be surprised if other manufacturers has slightly different forecasts for ordinary nimh cells. 

This should be taken as an indication only of what to expect. It could be a little longer, it could be a little shorter. As said before it also very much depends on your needs and how "picky" you are. 




> Typically NiMH batteries can be recharged hundreds of times, potentially allowing them to be equivalent to hundreds of alkaline batteries in total service over their lifetime. However, battery life is limited to 5 years or less.
> 
> http://data.energizer.com/PDFs/nickelmetalhydride_appman.pdf


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## MidnightDistortions (Nov 20, 2014)

*Re: How does the discharge curves of Eneloop Pros compare to standard AA & AAA Eneloo*



Viking said:


> Hi MidnightDistortions
> 
> A nimh cell will not last several decades unless you really appreciate the term ”crap cells”
> 
> ...



LSD technology hasn't exceeded the 10 years quite yet. The AAA Energizers i got in 2006 (that were manufactured in 2006) are still in excellent condition. They have lost some capacity but still retain a good charge. What i determine a crap cell is when they have less than 65% capacity (which could be used in lower drain devices), unless the device does not work enough for my needs or they self discharge within a few weeks. The Duracells i have (from 2005) last 3-4 months before i have to recharge them. HSD NiMHs i can totally understand they would deteriorate quicker due to the self discharging (which i consider them cycles when they start to lose their charge) and chances are if you don't use up all the cycles they go bad anyway from non usage. Of course as they age and you use them their performance starts to degrade, but considering Eneloops were built to hold a 70% charge after 5 years in storage one would speculate they'd get more than 10 years out of them. Of course that's just speculation & that's where a real world test with proper care to see how long Eneloops will last unused (other than maybe maintenance cycling).

Also NiMH cells are best recharged at 40% instead of 20% (i forgot what the reserve charge is at) but i generally recharge them at 1.20 volts instead of when they stop working (high drain devices with voltage cut off points are a bit easier since they won't fully discharge the battery). With that being said buying new Eneloops every 10 years isn't a bad thing but i wouldn't replace all my Eneloops every 10 years so working with crap batteries isn't a bad deal. The low drain devices work just fine and when the batteries no longer function or lasts a few hours at a time is when i think it's time to retire those batteries. In fact i got older Alkaleaks that work fine in remotes and stuff but i rarely need those plus i have to remember to take them out after every use so they don't leak. Still they are my emergency stock when i need a working remote, at least for now. In 5 years i should no longer have any Alkaleaks in my apt other then maybe the carbon dioxide alarm.


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## MidnightDistortions (Nov 20, 2014)

*Re: How does the discharge curves of Eneloop Pros compare to standard AA & AAA Eneloo*



Viking said:


> Hi WalkIntoTheLight
> 
> I agree the initial capacity has a lot to say about the longevity of the cell. My experiences with high capacity cells isn't that good either. But that's probably one of the reasons Energizer states 5 years as a maximum life expectancy. For high capacity cells this would probably be less.
> 
> ...



Yeah higher capacity cells don't last very long. Though Energizers claim their batteries only last 5 years mostly because of the dumb charger method. I don't know if Energizers still have dumb chargers today but if you take good care of the cells you should get around 10 years. Duracell claims you can get 5 years out of their 2400mAh batteries. Of course there are factors involved like you said life expectancy could be longer or shorter. Performance wise that's basically what you would expect but i'd expect i'll get 10 years out of those batteries (maybe more). I could have easily gotten 10 years out of the HSD Duracells if i knew draining them fully would reduce their capacity and had a smart charger but i only realized they were crap when i got a smart charger too! I haven't used them in high drain devices in a while but they still retain a charge for a good amount of time as if they were new. Thankfully the AAA Energizer cells were not subjected to the consistent full drain the Duracells had and still produce a good amount of mA.


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## tripplec (Nov 20, 2014)

*Re: How does the discharge curves of Eneloop Pros compare to standard AA & AAA Eneloo*

Well I just returned some Duracell HSD cells that were rated at 2450 and testing them new I was only getting 1094mAH max on the best of them. LOL I believe they were the first generation. I know now there were not the "Duraloop" type lots of people refer to (having the white top around the +ve tip). I don't know how their most current cells perform are even worth considering them. I was extremely disappointed. Oh and this just occurred this week. I purchased them on Amazon.ca

Without a smart charger you wouldn't know if they were any good. Fortunately I do and responded right away. Back they went after a days waste of time working with them and figuring out which ones I actually go.


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## Viking (Nov 21, 2014)

*Re: How does the discharge curves of Eneloop Pros compare to standard AA & AAA Eneloo*

Hi MidnightDistortions

I think you misunderstand my post a little bit. When I say I personally estimate my eneloops to last about 10 years , that is just an estimation nothing more than that. There is definitely the possibility they will last beyond that timeframe. I just see 10 years plus minus a couple of years as a realistic estimation.

It was the possibility of several decades I found unrealistic. You are right LSD cells hasn't been on the market 10 years , so the overall experiences is limited somewhat. But it is still basically ”just” improved nimh technology. And we have after all accumulated some experiences to go by. A few actually have discarded them "allready" both the regulary and the pro versions here on this forum. 

The estimation was based on what other people have experienced , and my own cells performance after 4 years ( generation 2 ). My cells are also still going strong , but they are not in mint condition anymore , neither would I have expected them to be. If we disregard the initial cycles , nimh cells will slowly deteriorates over there lifetime with accelerated rate. However in the beginning you will have to measure them to notice any differences. And it might even be possible to postpone the deterioration for some time with the right cycle care program. SilverFox have quite good experiences with that. But otherwise they will slowly but surely deteriorates , at least mine does. Again this is only natural and what I would have expected. They are in every way by far my best cells yet.

On the link below a fellow forum member has done some cycle testing. Although this is an accelerated test and no real life scenario , it should give you a feeling what is going on over the long run. If it wasn't for the measurements he would almost certainly not have noticed any differences with the cells. But they have never the less slowly deteriorated , just as mine has.
I wouldn't have noticed any differences either if it wasn't for my measurements. I monitor my cells quite closely , and keeps records of them individually.

http://www.candlepowerforums.com/vb...yo-2700-vs-Eneloop-100-Charge-Cycles-Analysis

About the maximum life expectancy claim from energizer. I don't think a dumb charger has much to do with that for the following reasons.

First of all energizer do offers smart chargers as well , and a dumb charger isn't actually harmful if used properly and is designed for the cells. This basically means a slow charging rate below 0.33C , without excessive overcharge. And the claim is after all the maximum life expectancy , not the minimum.

But secondly and most importantly the claim is regardless of cycles. Under actual typical use they are more conservative , like Panasonic also used to be with their HSD cells , with a claimed life expectancy of normally 2 years if used under proper conditions and not overcharged or overdischarged. I don't know about panasonic's life expectancy estimates for there new evolta LSD cells , but it is undoubtedly longer.

Regarding the duracell claim of 5 years of service. That is for LSD cells Technology if we are talking about the 2400 mah Duralock Power Preserve cells.
As said in the post before I think LSD cells has proven to be more resilient than ordinary nimh cells. That's the reason I estimates my eneloops to last not 5 years as duracell is promising but about 10 years give or take 

With regard to your statement that old HSD cells can last 10 years or longer.
That is maybe true , but I wouldn't expect it to be typical. 
And what we both seems to agree upon , that probably also very much depends on the requirements the user set for whether they are in good condition or not. 

Personally all my 10+ years HSD cells are labeled "crap cells" long time ago. I didn't regularly ran them through exercise cycles or any thing like that though. 
I still have most of them but only for testing purposes , although some can still be used. But they are not in good working order by my standards.


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## tripplec (Nov 21, 2014)

*Re: How does the discharge curves of Eneloop Pros compare to standard AA & AAA Eneloo*

Has anyone done a capacity test on the new Duracell rechargeable batteries that are currently sold. I believe they're LSD in their latest "Ion Core" moto. The link above had stand alkalines in the group only from big D.


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## Viking (Nov 21, 2014)

*Re: How does the discharge curves of Eneloop Pros compare to standard AA & AAA Eneloo*

If you are talking about these they are might rebranded eneloop XX according to NLee. 
Look under the rewiews.

http://www.amazon.com/dp/B00DSYFAEQ/?tag=cpf0b6-20



> The above behaviors looked suspiciously similar to my test result for the Sanyo Eneloop XX AA batteries back in 2011. Average capacity of Sanyo XX cells I measured was almost identical at 2610mAh, even though they are advertised as '2500mAh'.
> 
> I compared the physical appearances of those Duracell 'ion core' AA cells against Sanyo XX cells. As far as I can tell, they are exactly that same! See the picture I uploaded to the 'customer images' section, and you can notice that the two brands have identical-shaped positive and negative terminals, down to their 'vent holes' and how their wrappers overlap. Therefore to my best guess, the Duracell 'ion core' precharged AA cells are just rebranded Sanyo XX cells.


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## tripplec (Nov 21, 2014)

*Re: How does the discharge curves of Eneloop Pros compare to standard AA & AAA Eneloo*



Viking said:


> If you are talking about these they are might rebranded eneloop XX according to NLee.
> Look under the rewiews.
> 
> http://www.amazon.com/dp/B00DSYFAEQ/?tag=cpf0b6-20



They appear to be the current produce from what I am seeing on Duracell's website. They don't list/show the other version hence discontinued. 

As for where to look. Very good that's my next search now. Thx


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## ChrisGarrett (Nov 21, 2014)

*Re: How does the discharge curves of Eneloop Pros compare to standard AA & AAA Eneloo*

I have four (new/out of the pack) Duracell Iron Core 2450mAh AAs (made in Japan) here that I broke in on my Maha C-9000 on 1-5-13. I wrote everything down, much like I did in my Eneloop/GP ReCyKo/Imedion AA 1 year test and then my 12 Duraloop 2000 (Eneloop Gen. 2.) one year test.

In another ~6 weeks, I'll discharge them down at 400mA and see what's left, to get an idea of whether they're XX/Pros, or not. I don't have a control group here utilizing the genuine XX/Pro AAs, but seeing what's left in the tank should give us all an idea if they adhere to what Sanyo/Panasonic claims 'should be left' after a full year.

Chris


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## MidnightDistortions (Nov 22, 2014)

*Re: How does the discharge curves of Eneloop Pros compare to standard AA & AAA Eneloo*



Viking said:


> Hi MidnightDistortions
> 
> I think you misunderstand my post a little bit. When I say I personally estimate my eneloops to last about 10 years , that is just an estimation nothing more than that. There is definitely the possibility they will last beyond that timeframe. I just see 10 years plus minus a couple of years as a realistic estimation.
> 
> ...



Lifespan is all based on how they were manufactured, stored, charged/discharge, usage and maintenance. But also like you said there is some sort of degradation, some are inevitable to become useless and there's nothing you could do if there is physical damage/degradation. Personally i would not have known my 10 year old HSD cells were crap cells if i didn't have a smart charger or the USB charger i have that the crap cells did not produce the mA i needed. But i would expect it wouldn't take that long considering most of them need consistent recharging to maintain capacity and whether you use them or don't they will deteriorate anyways due to the HSD issue. All NiMH cells lose maximum capacity when fully discharged regardless, Eneloops and the other quality batteries might retain a bit more then ones that were crap to begin with (like the La Crosse batteries that come with their charger) but they all do pretty much the same and that's what happened to my older Duracells, but they still maintain a good level of self discharge.

Forgive me since i have only been experiencing problems with my older cells recently (a year for the Duracells, Energizers were crap since 2009-2010), had less than 20 AA NiMHs and have only had a smart charger since the beginning of this year along with learning about NiMHs so i still lack a bit of experience and much of what i am saying is speculation here. I just figured since LSD NiMHs function to similarity with Alkalines (except for voltage, leakage). I don't know what the AAA Energizers cycles are at (rated at 900mAh) but the ones i currently have which are about 8 years and still have at least 70% capacity in them. They might be considered as crap cells but so far they are outpacing the other older AA batteries even though they are a year behind of the AA cells i own, but they still perform strongly (no voltage depression/sagging like the AAs started doing) and i don't know when they will start declining like the Duracells and the worse AA Energizers i have but i'll do another refresh within 3-5 months to see. So pretty much the AA Energizers only lasted 4-5 years which is within the normal time frame. The Duracells were closer to 5-8 years, i'm guessing here as i don't know how much capacity was lost with those considering they still retain charge for normal HSD compared to the Energizers which only lasts about a week or less. As for Energizer chargers, i'm a bit uninformed about those.. i only know of several that are cheap chargers, i got one of them that i think has a timer which could be partially why the AA's were junk early on, but for some reason that charger did well for the AAA's but i did try to drain the AAA's down as much as i could, using them in my PC keyboard, other low drain devices and later on in an AAA incan Maglite. Duracells were left unused for a bit but sometimes was used in CD players or later on a mouse i got in 2011 so them being left unused for awhile must have caused them to lose capacity and voltage depression.

But otherwise with the AAA Energizers lasting 8 years and still performing like new (minus the lost capacity) is the reason for me thinking that the Eneloops would function better. They might have just been really well manufactured batteries that stood the test of time or that AAA's have a longer lifespan than the AA's do. In fact just thinking about it, the La Crosse AAA's perform better than the AA's i got, but then those AA's have been abused in my USB charger, realizing that it's not a good idea to let the batteries drain fully in that. One of the batteries overheated (melted the plastic wrapper) while charging at 500mAh so either those batteries are just crap or can't handle heavy DoD to 20%. I certainly am not saying that LSD batteries (Eneloop technology) will last several decades, but what i am saying is based on whether the conditions are right and i am taking a guess that they 'could' theoretically last that long given proper care and less frequent use, shallow discharging and used in low drain devices. That link you posted does give me an indication that under heavy usage Eneloops would last 5-10 years based on cycles/DoD. If you were to drain them completely every day or every other day they would give out a lot quicker than if you were to do the same but every week. They might retain a capacity a bit better if they were only drained to 40% and charged back up but again that's just speculation here because i have not owned Eneloops for more than a year (got the 16 pack when i found out my cells were crap from the La Crosse charger). As you said that some users of Eneloops do not keep their cells for 10 years. The same 'use it or lose it' would then also apply to LSD batteries as well if cell degradation happens even with Eneloops. Everything pretty much degrades over time anyhow, some materials/manufactured products and i wouldn't expect anything to last a lifetime considering our current economic structure is built that way. If we wanted to though we could build a battery that will last a long time but that wouldn't be a very good source of income if no one ever needed to replace them.

I am sure some of the Eneloops i own will prove useful in determining how long they will last, at least with the Japanese build. But then i wonder if the 2100 cycles is even a realistic number and it's really a gimmick, you wouldn't know how many cycles you used unless you write each one down. We do know that Eneloops do provide excellent performance but then it would make a bit more sense to go by years such as Duracell does, to say "Guaranteed to last 5 years" or 400 recharge cycles and a more realistic lifespan for basic Eneloops would be 10 years. Even then after 4 years Eneloops are capable of losing capacity.


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## Viking (Nov 22, 2014)

*Re: How does the discharge curves of Eneloop Pros compare to standard AA & AAA Eneloo*



MidnightDistortions said:


> much of what i am saying is speculation here.



That applies for meas well 
I'm not at all sure about my approximately 10 years give or take estimation for eneloops. It was nothing more than a guess really. Actually I'm starting to think I'm being a little too conservative. 
Over the years I can recall reading 3 posts where people have stated significant losses of performance.
1 for ordinare eneloops , and two for eneloop XX.

Compared to how many that have observed no change , that isn't much at all. These cells just keeps impressing me.
As said I wouldn't have observed any change either if it wasn't for my measurements.They are still going strong , and the capacity loss is only marginally downwards.



> But otherwise with the AAA Energizers lasting 8 years and still performing like new (minus the lost capacity) is the reason for me thinking that the Eneloops would function better.



I think they will too. But with a 30 percent capacity loss I would have labeled them"crap cells" nevertheless. That's because I recall SilverFox did some testing that proved to me that 80 percent remaining capacity was a practical limit to set. When the cells first came below that it was downhill relatively fast and I don't like surprises in the field so to speak. 



> But then i wonder if the 2100 cycles is even a realistic number and it's really a gimmick, you wouldn't know how many cycles you used unless you write each one down.



I agree very few people will ever reach 2100 cycles. But I don't think it's a gimmick.
I believe it tells you something about the robustness and healthiness of the cell.
Whether or not they are able to reach those numbers in practice with a reasonable performance is an open question. Some believe they can others do not.

But what matters to me is I believe a 2100 cycle cell is overall a more robust and healthier cell than a 1500 cycle cell. I personally think there is a good chance the cell that has proven to be more robust during the cycle test , also will be a little more resilient to old age as well. And old age deterioration will probably be the cause for most people to discard the cells , rather than the cycle numbers. 




> it would make a bit more sense to go by years such as Duracell does, to say "Guaranteedto last 5 years" or 400 recharge



I agree. I would also like to see a minimum life expectancy in years as well.


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## WalkIntoTheLight (Nov 22, 2014)

*Re: How does the discharge curves of Eneloop Pros compare to standard AA & AAA Eneloo*



Viking said:


> I think they will too. But with a 30 percent capacity loss I would have labeled them"crap cells" nevertheless. That's because I recall SilverFox did some testing that proved to me that 80 percent remaining capacity was a practical limit to set. When the cells first came below that it was downhill relatively fast and I don't like surprises in the field so to speak.



I wouldn't throw away cells just because they're down to 80% capacity. It may be true by that point they've used up most of their cycles, but if you switch their usage to things like remote controls and clocks, the few dozen cycles they have left can last a very long time.

That assumes they still have many years left, even if their cycles are limited. As based on my observations of old cells, they don't seem to wear out from age very quickly. Most of my 14+ year old cells are still going. They can't be used in high-drain applications, but they're fine in low-drain.



> But what matters to me is I believe a 2100 cycle cell is overall a more robust and healthier cell than a 1500 cycle cell. I personally think there is a good chance the cell that has proven to be more robust during the cycle test , also will be a little more resilient to old age as well. And old age deterioration will probably be the cause for most people to discard the cells , rather than the cycle numbers.



Perhaps. But, I'd rather have a 1500 cycle Japanese Eneloop, than a 2100 cycle Chinese Eneloop.


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## MidnightDistortions (Nov 22, 2014)

*Re: How does the discharge curves of Eneloop Pros compare to standard AA & AAA Eneloo*



Viking said:


> That applies for meas well
> I'm not at all sure about my approximately 10 years give or take estimation for eneloops. It was nothing more than a guess really. Actually I'm starting to think I'm being a little too conservative.
> Over the years I can recall reading 3 posts where people have stated significant losses of performance.
> 1 for ordinare eneloops , and two for eneloop XX.
> ...



It's normal to exhibit some signs of lost performance within the first 5 years. After the first 5 years it's only a matter of time before they start to decline in capacity. More the reason to do yearly refreshing even on LSD NiMHs. It can't hurt to use up some cycles you'll probably never use up anyhow . 



> I think they will too. But with a 30 percent capacity loss I would have labeled them"crap cells" nevertheless. That's because I recall SilverFox did some testing that proved to me that 80 percent remaining capacity was a practical limit to set. When the cells first came below that it was downhill relatively fast and I don't like surprises in the field so to speak.



Yeah if you're in the field and expect the cells to last 10 hours and you're only getting 9 or less hours. All (or most) batteries regardless of type do this. Generally refreshing the batteries will reduce the run time a bit no matter what but you'll get better performance than if you were to never refresh them (flashlights going dim early on or moving parts do not move as efficiently). Heck, the 2500 AA Energizers worked ok in my AA Mini Maglite for awhile at least until the HSD got worse to where i need to recharge them every other day. They still average around 40-50% so i just use them in my incandescent during the night. It works fine and i got an extra set on standby if i need it. I replaced my Mag with some LSD Energizers (before i realized that Eneloops worked in that light) so i got that light if i ever run out of juice and it's currently my EDC though the AAA Energizers worked fine when my AAA Mag was still working (it broke recently) but i hardly had to worry about those batteries, just had to check the voltage on them often (i even do that with the new Energizers when the light is being used). I certainly don't like surprises in the field either but then that's usually when you should have a backup if possible . 



> I agree very few people will ever reach 2100 cycles. But I don't think it's a gimmick.
> I believe it tells you something about the robustness and healthiness of the cell.
> Whether or not they are able to reach those numbers in practice with a reasonable performance is an open question. Some believe they can others do not.
> 
> ...



After reading my comment about the 2100 cycles, i didn't realize that DoD % could factor into how many cycles you get out of the battery. They could be 2100 cycles and you would only be discharging them to about 50% while draining them to near death may have less cycles but as you said would be more robust than the 1500 cycle Eneloops. 



WalkIntoTheLight said:


> I wouldn't throw away cells just because they're down to 80% capacity. It may be true by that point they've used up most of their cycles, but if you switch their usage to things like remote controls and clocks, the few dozen cycles they have left can last a very long time.
> 
> That assumes they still have many years left, even if their cycles are limited. As based on my observations of old cells, they don't seem to wear out from age very quickly. Most of my 14+ year old cells are still going. They can't be used in high-drain applications, but they're fine in low-drain.
> 
> ...



In regards to my older AA Duracells and Energizers, the Energizers cycles have already been used up and probably have been over discharged too many times, thus both batteries brands have voltage depression. The Duracells i think was either overcharged or doesn't get as many refreshes as they needed. They also sat for awhile so some of their capacity wasn't salvageable in refreshing them. The AAA Energizers on the other hand have been powering my keyboard and AAA Maglite so they stayed in relatively good shape. And if you couldn't tell i like to type up a storm and probably use it more than my TV remote. Also since the batteries last several months on a single charge refreshing the batteries don't seem to be necessary, but now i will probably have to let them trickle charge for a few hours or so on the charger since i no longer will use the Energizer charger.


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## Viking (Nov 23, 2014)

*Re: How does the discharge curves of Eneloop Pros compare to standard AA & AAA Eneloo*



MidnightDistortions said:


> After reading my comment about the 2100 cycles, i didn't realize that DoD % could factor into how many cycles you get out of the battery. They could be 2100 cycles and you would only be discharging them to about 50% while draining them to near death may have less cycles but as you said would be more robust than the 1500 cycle Eneloops.



Yes many things come into play. That's the reason I think it's not that simple just to transfer the test results made under laboratory conditions with real life conditions.
It's no secret I personally am a little sceptical with those cycle numbers. But as said I find them useful nevertheless.

If you wanna know how they come up with the numbers. You can see it in the link below under section 7.4.1.1 ( Table 9 ).

As you can see both charge and discharge are done under gentle rates followed up by a break-in every 50 cycle. The airflow around the cells is probably better since forced ventilation is permitted to keep temp. under 35°C if necessary. The voltage will never come below 1.0 volt during discharge.

On the other hand. There isn't much resting time like there would be in almost any cases under real life conditions. And the cells will probably get overcharged before they regularly get drained down to 1.0 volt every 50 cycle. However whether this is actually damaging under these low charging rates combined with the limited period of time I think is questionable. But I'm not sure about this.


http://www.cnlumos.com/lumos/Battery Knowledge/Battery Standards/IEC61951-2-2003.pdf


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## MidnightDistortions (Nov 23, 2014)

*Re: How does the discharge curves of Eneloop Pros compare to standard AA & AAA Eneloo*

Interesting. Yeah in real life conditions Eneloops are probably overcharged over time making them weaker, usually refreshing them remedies that problem. I'm not too worried about that as i will take Eneloops off the charger once -dV hits.


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## Viking (Nov 23, 2014)

*Re: How does the discharge curves of Eneloop Pros compare to standard AA & AAA Eneloo*

I think it will more likely be the higher temperature , charge and discharge rates , as well as the deeper discharges and and lack of regularly break-ins , that will be the cause for poorer performance.

For example will the cells under real life conditions be inserted in a little closed compartment , very tight next to each other with no room for the heat to escape , unlike in the laboratory test.

Overcharge shouldn't be much of a problem with the right charger. Actually it should rather be less than under the IEC test I would say.


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## MidnightDistortions (Nov 24, 2014)

*Re: How does the discharge curves of Eneloop Pros compare to standard AA & AAA Eneloo*

Yeah, that makes sense. I was reading an older post on proper care of Eneloops, here: maintaining Eneloops and seeing how leaving Eneloops sit for a few years could cause poor performance as well. Just like any other NiMHs it's best to use them. You could probably get away with using them at least once a year (refreshing/break-in) but you'd probably be better to use them a little more frequently. Regarding needing them as emergencies, most of my set is charged and ready to go and i am still getting use out of my crap cells, which i haven't used my Eneloops other than one set in my 2D Maglite.


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## WalkIntoTheLight (Nov 24, 2014)

*Re: How does the discharge curves of Eneloop Pros compare to standard AA & AAA Eneloo*



MidnightDistortions said:


> Yeah, that makes sense. I was reading an older post on proper care of Eneloops, here: maintaining Eneloops and seeing how leaving Eneloops sit for a few years could cause poor performance as well. Just like any other NiMHs it's best to use them. You could probably get away with using them at least once a year (refreshing/break-in) but you'd probably be better to use them a little more frequently.



I have not seen any testing that would confirm that, nor any official statements from Sanyo that mentions that.

Why would an unused cell accumulate any more permanent damage than a used cell?


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## MidnightDistortions (Nov 24, 2014)

*Re: How does the discharge curves of Eneloop Pros compare to standard AA & AAA Eneloo*



WalkIntoTheLight said:


> I have not seen any testing that would confirm that, nor any official statements from Sanyo that mentions that.
> 
> Why would an unused cell accumulate any more permanent damage than a used cell?



I worded that wrong, should have stated that Eneloops left unused need to be break-in/refresh to restore peak performance.


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## WalkIntoTheLight (Nov 25, 2014)

*Re: How does the discharge curves of Eneloop Pros compare to standard AA & AAA Eneloo*



MidnightDistortions said:


> I worded that wrong, should have stated that Eneloops left unused need to be break-in/refresh to restore peak performance.



Okay, that could be. I've never checked that myself (to see if a refresh is needed for LSD cells), but I usually do it for cells that have been sitting for 2 or 3 years. At the very least, it lets me know that the cells are still good.


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## theilluminati (Nov 26, 2014)

*Re: How does the discharge curves of Eneloop Pros compare to standard AA & AAA Eneloo*

Interesting thread; got too advanced for me (


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## tripplec (Nov 26, 2014)

*Re: How does the discharge curves of Eneloop Pros compare to standard AA & AAA Eneloo*

I am sure you'd find Eneloop in distribution for years before being sold. Same thing and if they were not performing to spec's when purchased there would be a big problem. Especially those packaged with the dumb chargers some come with. At their price I doubt they're flying off the shelves that fast.


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## MidnightDistortions (Nov 26, 2014)

*Re: How does the discharge curves of Eneloop Pros compare to standard AA & AAA Eneloo*



WalkIntoTheLight said:


> Okay, that could be. I've never checked that myself (to see if a refresh is needed for LSD cells), but I usually do it for cells that have been sitting for 2 or 3 years. At the very least, it lets me know that the cells are still good.



Yeah, i have no idea if they need it but it's one of my things anyway to fully deplete the battery yearly or so to keep them in good shape or at the very least letting me know whether they are good (makes me wish all chargers come with a fancy LCD screen and shows the mA capacity). I think it mostly depends on how often you use them and the level you discharged them at.


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