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Thread: Japanese Vs Chinese Eneloop Cycle Testing Results

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    Default Japanese Vs Chinese Eneloop Cycle Testing Results

    At about the start of 2014, Panasonic shifted production of Eneloops for some markets (including Australia) from Japan to China.

    The Chinese Eneloops have the same product code as the Japanese made Eneloops and are rated for the same 2100 cycles. The Chinese cells are rated slightly lower on capacity retention with a claimed 65% remaining after 5 years instead of 70%

    When I heard about this change, I was immediately concerned that even though the Chinese made Eneloops were rated for the same number of cycles, they may not actually be as good as those made in Japan. Time for another test!

    For this test, I took a pair of 4th generation Japanese made Eneloops and a pair of new 4th generation Chinese made Eneloops. I put one of each into 2 separate chargers and set them running with both charging and discharging at 2 amps. 20 minutes rest after charging and 10 minutes after discharging. The results of the test is shown below:



    Please note that at the time of posting this, the Japanese Eneloops (shown in blue) are still running where as the Chinese Eneloops (in green) died quite a while ago.

    It seems quite clear to me from this test that under these conditions at least, the Chinese Eneloops perform well below what the Japanese made Eneloops are capable of. These Chinese Eneloops have performed better in this test than the 1st gen Japanese made Eneloop that I previously tested, however, that may be due to this test being done over the cooler Winter months. The testing method also isn't exactly the same, so that could also have an effect on the result. It should also be noted that the 4th gen Japanese Eneloops tested better than the one in my previous test as well.

    A while ago, I contacted Panasonic Australia to confirm that the Japanese and Chinese Eneloops are rated using the same testing method and was told that they were. Initially, I was told that the Chinese made Eneloops were just as good or even better than those made in Japan. When I pointed out that the Chinese Eneloops were rated for less capacity retention and asked if there was any situation in which the Japanese cells could work better, the response was less defensive of the Chinese cells and admitted that there could be some differences in performance.

    About 2 weeks ago, I contacted Panasonic Australia again to seek a comment on these test results. I was initially asked to send through my results and asked for details about my testing methods. I sent those details through as requested, but initially received no response. After a couple of days, I sent a follow up email to see if my previous email had been lost to which I received an email confirming that my email had indeed been lost to the spam folder. In that email, I was told that my results would be reviewed at the start of the following week (now last week). I have received no further response from Panasonic despite sending them a follow up email.

    I do understand that moving production to China, etc is quite normal these days, and I can certainly understand the reasons for doing so. What I really don't like is when companies move production to a country with lower wages and reduce the quality, but don't admit to it and continue to charge the same prices as they were before. In Panasonic's defence in this case, it appears that the reduced costs are actually having an impact on local pricing here in Australia. Previous 3rd generation Eneloops generally went on sale at Dick Smith Electronics for $20 for a pack of 8. Since the Chinese Eneloops have made an appearance here, they've been discounted to $15 for an 8 pack numerous times.

    It's speculated that when Panasonic purchased Sanyo, they only acquired the Eneloop brand and the Japanese factory that produces Eneloops was sold off to a third party to ensure that there weren't any anti-trust issues that would otherwise block the purchase due to Panasonic potentially controlling an excessive proportion of the worldwide battery production capacity. There are still Eneloops being produced in Japan for some markets, but other markets are being sold Chinese made Eneloops instead. For customers in those markets, it seems that Eneloops are now only Eneloops in name.

    Having said all of the above, I'm somewhat disappointed in Panasonic. I have a number of other Panasonic branded items in my household and have generally been quite happy with them all, but this is leaving a bitter taste in my mouth.
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  2. #2

    Sigh Re: Japanese Vs Chinese Eneloop Cycle Testing Results

    Quote Originally Posted by Power Me Up View Post
    they've been discounted to $15 for an 8 pack numerous times.
    Sad to know that eneloop is no longer eneloop...but they were on sale for $2 a 8 pack last week, can't really complain that...

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    Default Re: Japanese Vs Chinese Eneloop Cycle Testing Results

    Quote Originally Posted by tintomatic View Post
    Sad to know that eneloop is no longer eneloop...but they were on sale for $2 a 8 pack last week, can't really complain that...
    Yep - I ended up with 3 packs for a whole $3.96. DSE stuffed up and sent AA packs instead of AAA packs - I had ordered a pack of each, but ended up with 2x AA packs and 1x AAA pack. I'm not the only one that ended up with an extra pack - others have reported that they've been told to just keep the extra pack... Worked out to 66 cents per set of 4 - I've never bought rechargeables that cheap before and I dare say it'll never happen again!
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    Default Re: Japanese Vs Chinese Eneloop Cycle Testing Results

    Quote Originally Posted by Power Me Up View Post
    There are still Eneloops being produced in Japan for some markets, but other markets are being sold Chinese made Eneloops instead.
    Very interesting comparison test, thanks! Quite sad though. I wonder what markets will still carry the Japanese Eneloops and for how long before we all sing RIP Eneloops.
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    Default Re: Japanese Vs Chinese Eneloop Cycle Testing Results

    The Chinese brand is terrible. I don't know what Panasonic is thinking. Long as i can get the Japanese ones there should be no problems, hopefully amazon will still carry or at least give some options. I'll be switching back to Duracell if Eneloops are not made in Japan anymore.

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    Default Re: Japanese Vs Chinese Eneloop Cycle Testing Results

    Very interesting, thanks for the post. Shame that Panasonic aren't responding but what can they say?

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    Default Re: Japanese Vs Chinese Eneloop Cycle Testing Results

    Quote Originally Posted by Milo Fisher View Post
    Very interesting, thanks for the post.
    No problem!

    Shame that Panasonic aren't responding but what can they say?
    If they could see an error in my testing method, they could point that out, but not much else beyond that as far as I can see.
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    Default Re: Japanese Vs Chinese Eneloop Cycle Testing Results

    Even though I previously have expressed my concerns , I must admit this test result is somewhat worse than I suspected it might would be.

    I also think we should take into account that the 1. generation eneloops the chinese made seemingly beats was approximately 7 years old during the test. Thats 2 more years than the max life expectancy for ordinary nimh according to energizer. Although I personally believe LSD nimh has longer life expectancy , I don't think they were in new condition as the chinese cells obviously should be in.

    I will still recommend eneloops ( or Fujitsu ) , but in the future specify they should be the japanese made ones. Luckily in Europe they still are.

    Also I find panasonic's lack of response after 2 inquiries to a customer , who quite obviously have spent a lot of time and efforts to make some serious homework testing kind of arrogant.

    At least you get a thumbs up from me for your serious work. Thanks Power Me Up


    Quote Originally Posted by Milo Fisher View Post
    Shame that Panasonic aren't responding but what can they say?
    A simple answer ( almost any kind ) would have been the polite way to respond in my opinion.
    Last edited by Viking; 11-04-2014 at 06:17 AM.

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    Default Re: Japanese Vs Chinese Eneloop Cycle Testing Results

    This is really useful information, and unfortunately shows a much greater difference than I ever would have expected. I'm glad I stocked up on Japanese Eneloops earlier this year, though now I wished I had bought some more AA's.

    It's very disconcerting that there's no way to tell in advance (if you mail-order) where they are manufactured.

    Hopefully, Fujitsu will manufacture them under a different brand.

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    Default Re: Japanese Vs Chinese Eneloop Cycle Testing Results

    Thanks for testing this. Will contact my Eneloop-seller now, before I order.
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    Default Re: Japanese Vs Chinese Eneloop Cycle Testing Results

    Quote Originally Posted by Viking View Post
    I will still recommend eneloops ( or Fujitsu )...
    Fujitsu? Where? They're hard to find, even on Amazon.
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    Default Re: Japanese Vs Chinese Eneloop Cycle Testing Results

    Quote Originally Posted by kj2 View Post
    Thanks for testing this. Will contact my Eneloop-seller now, before I order.
    Yep, this is the best way for now. In fact i'd contact your seller and let them know you prefer Japanese Eneloops. Even be willing to pay extra if that's what it takes to get better quality batteries. Those areas that have already gone to the Chinese Eneloops might give Panasonic an idea that consumers do want to pay a premium for better quality, though you shouldn't have to pay twice as much as Japanese Eneloops already is. I thought i read somewhere that Eneloops were guaranteed to last 10 years provided that they were well taken care of and the cycles have not been used up within that time frame.

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    Default Re: Japanese Vs Chinese Eneloop Cycle Testing Results

    Quote Originally Posted by Tapis View Post
    Fujitsu? Where? They're hard to find, even on Amazon.
    In Europe they can be purchased at the link below to a decent price. I don't know about Canada.
    But yes they are undoubtedly much harder to find at a competitive price.

    http://ru.nkon.nl/rechargeable/aa-si...s-in-case.html

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    Default Re: Japanese Vs Chinese Eneloop Cycle Testing Results

    I'm in Europe right now so I will purchase some wherever I see them, in a shopping mall or elsewhere. I hope the package clearly indicates whether they're made in Japan or China.
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    Default Re: Japanese Vs Chinese Eneloop Cycle Testing Results

    Unfortunately I can't help you there. Here in Denmark neither eneloops or the Fujitsu's are widely available in retail stores. Actually I don't know of any retail store that sells either one of them. My eneloops are therefor purchased online.

    But if you buy from an authorized dealer, I think you can count on the Eneloops are made in Japan. And these particular Fujitsu cells I think are only made ​on the FDK factory in Japan. Be aware though , I think Fujitsu makes other cells as well , but not with this particular item number.

    Another thing to look after ( beside "made in japan" of course ) is the 65 % vs. 70 % remaining capacity after 5 years for the eneloops , as already mentioned by Power me up.
    Last edited by Viking; 11-04-2014 at 11:23 AM.

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    Default Re: Japanese Vs Chinese Eneloop Cycle Testing Results

    Thanks for the test. I would have used no more than 1A, but in any case your test shows they are not the same cells. Too bad.

    Most companies require much larger timeframes to respond to questions like this so I'm not surprised you have not heard back yet. I would not be surprised if you hear back later later. They may be trying to duplicate the results, but I suspect that is not the case because i believe they already have tons of test data.

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    Default Re: Japanese Vs Chinese Eneloop Cycle Testing Results

    Quote Originally Posted by StandardBattery View Post
    Thanks for the test. I would have used no more than 1A, but in any case your test shows they are not the same cells. Too bad.

    Most companies require much larger timeframes to respond to questions like this so I'm not surprised you have not heard back yet. I would not be surprised if you hear back later later. They may be trying to duplicate the results, but I suspect that is not the case because i believe they already have tons of test data.

    I cannot see any reason why they would even want to reply,perhaps if the test data was some university or similar they may show some interest.
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    Default Re: Japanese Vs Chinese Eneloop Cycle Testing Results

    Quote Originally Posted by mcnair55 View Post
    I cannot see any reason why they would even want to reply,perhaps if the test data was some university or similar they may show some interest.
    It's a big company, and the email probably got stuck in some low-level customer service rep's inbox. Basically, customer service reps aren't interested.

    If the email went to someone in quality control, they probably would care. Maybe they did forward it to QC, but a low-level manager got it and decided his department staff had enough work to do and this test wasn't in their mandate.

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    Default Re: Japanese Vs Chinese Eneloop Cycle Testing Results

    It might be possible they are discussing the results, otherwise they might not be interested in a consumer's test. It depends on whether Panasonic wants to investigate this and/or cares enough that the Chinese Eneloops are lower quality and want the best their batteries are capable of providing. The Eneloop videos on the site seem like Panasonic wants a cleaner environment so it would make sense that they want Japanese quality, but it doesn't change the fact that they are planning to switch to Chinese.

    One thing i realized with the test here is that you'd probably exceed the 500 cycles with giving much longer rest periods (say weekly or monthly cycling) but that would take too long to test, but i wonder if Panasonic did different tests instead of continually discharging/recharging the batteries whether the batteries need a recovery time in between cycles. Also the quality might have been similar in the beginning but degraded over time. I don't know how long the Chinese have been producing Eneloops for.

    Either way it doesn't change the fact the Chinese batteries fell below the Japanese ones which is clear cut that the Japanese Eneloops hold out better. If Panasonic is a trustworthy company which i believe them to be, they'd ditch the Chinese batteries or at the very least do an investigation on how the Chinese are manufacturing Eneloops and make some changes so the Chinese counterparts are of same quality.

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    Default Re: Japanese Vs Chinese Eneloop Cycle Testing Results

    Quote Originally Posted by StandardBattery View Post
    Thanks for the test. I would have used no more than 1A, but in any case your test shows they are not the same cells. Too bad.
    The test would have taken nearly twice as long in that case - probably longer since the cells would be expected to last for more cycles! The key thing was to find out if there is a difference between the Chinese and Japanese cells.

    Most companies require much larger timeframes to respond to questions like this so I'm not surprised you have not heard back yet. I would not be surprised if you hear back later later. They may be trying to duplicate the results, but I suspect that is not the case because i believe they already have tons of test data.
    Regardless of what is actually going on, IMHO, the courteous thing for them to do would have been to at least send me an email to say that they're still looking at the results and give an estimate of when they hope to be able to provide a response.

    The fact that they haven't responded at all since confirming that they have received my results is IMHO tantamount to an admission that they can't find any problems with my testing method...

    I agree that they've no doubt got plenty of their own test data. It would be interesting if they could release that data to show how their internal testing shows how the different cells compare, but I can certainly understand why they wouldn't want to do that...
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    Default Re: Japanese Vs Chinese Eneloop Cycle Testing Results

    Quote Originally Posted by mcnair55 View Post
    I cannot see any reason why they would even want to reply,perhaps if the test data was some university or similar they may show some interest.
    Well... They did show interest by asking for details about my testing method and for my results. Checking the last email that I received, it says that he would look at it early the following week - it doesn't actually say that he would respond though!
    Last edited by Power Me Up; 11-05-2014 at 02:26 PM.
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    Default Re: Japanese Vs Chinese Eneloop Cycle Testing Results

    So does the slow/fast refer to the charge rate at 50 Cycle intervals?

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    Default Re: Japanese Vs Chinese Eneloop Cycle Testing Results

    Quote Originally Posted by MidnightDistortions View Post
    It might be possible they are discussing the results, otherwise they might not be interested in a consumer's test.
    As I mentioned in my first post, they did show interest in my results and asked me to send them through...

    It depends on whether Panasonic wants to investigate this and/or cares enough that the Chinese Eneloops are lower quality and want the best their batteries are capable of providing. The Eneloop videos on the site seem like Panasonic wants a cleaner environment so it would make sense that they want Japanese quality, but it doesn't change the fact that they are planning to switch to Chinese.
    A good response from Panasonic could have gone along the lines that they're concerned by my test results and are actively investigating what might have gone wrong - that would certainly inspire a bit more confidence than simply going silent!

    One thing i realized with the test here is that you'd probably exceed the 500 cycles with giving much longer rest periods (say weekly or monthly cycling) but that would take too long to test, but i wonder if Panasonic did different tests instead of continually discharging/recharging the batteries whether the batteries need a recovery time in between cycles. Also the quality might have been similar in the beginning but degraded over time. I don't know how long the Chinese have been producing Eneloops for.
    There's some discussion of testing methods in the following thread:
    http://www.candlepowerforums.com/vb/...-Cycle-Testing

    Basically, the IEC standard which they're claiming to use is based on (mostly) incomplete charge/discharge cycles and with no rest at all for most cycles. Charge/Discharge rates are also much lower than what I was using in my test. The IEC standard should take about twice as long to run as the test method that I have been using.

    I would expect that it's more likely that the quality started lower and has been improved over time as the production process is fine tuned. Since both Chinese cells that I tested were from the same pack, it's possible that they came from a bad batch, or being from an early production run, it's possible that newer cells are capable of more cycles. I'm planning to run another test with at least one more Chinese cell that has been manufactured more recently.

    A good question that comes to mind is the fact that the IEC standard that is referenced on the back of the Eneloop packs would take around 18 months to get through 2100 cycles. How on earth have they managed to test the Chinese cells to that many cycles using that method when production in China has only been going for 12 or so months????

    Either way it doesn't change the fact the Chinese batteries fell below the Japanese ones which is clear cut that the Japanese Eneloops hold out better. If Panasonic is a trustworthy company which i believe them to be, they'd ditch the Chinese batteries or at the very least do an investigation on how the Chinese are manufacturing Eneloops and make some changes so the Chinese counterparts are of same quality.
    It would be really interesting to know what is going on within Panasonic with regard to the Chinese production of Eneloops!
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    Default Re: Japanese Vs Chinese Eneloop Cycle Testing Results

    Quote Originally Posted by WalkIntoTheLight View Post
    It's a big company, and the email probably got stuck in some low-level customer service rep's inbox. Basically, customer service reps aren't interested.

    If the email went to someone in quality control, they probably would care. Maybe they did forward it to QC, but a low-level manager got it and decided his department staff had enough work to do and this test wasn't in their mandate.
    The person that I was corresponding with is a "Business Manager"
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    Default Re: Japanese Vs Chinese Eneloop Cycle Testing Results

    Quote Originally Posted by StandardBattery View Post
    So does the slow/fast refer to the charge rate at 50 Cycle intervals?
    The fast cycles are the ones done at 2 amps charge and discharge - i.e. cycles 1-49. The 50th cycle is the one done with a slow 400 mA discharge.
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    Default Re: Japanese Vs Chinese Eneloop Cycle Testing Results

    Hi,

    This is definitely a great resource you're sharing with the forum. Do you have any similar testing done for other battery manufacturers such as Powerex, Imedion, Ansmann, Amazon Basics (Black and White ones), etc?

    Thanks.

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    Default Re: Japanese Vs Chinese Eneloop Cycle Testing Results

    I noticed for the first 200 cycles or so, the Chinese Eneloops had more capacity? Was this due to being charged fuller due to termination behavior differences? (which may reduce cycle life). Or maybe having slightly higher capacity degrades their life cycle performance. (something possibly seen in the eneloop XX vs turnigy comparison.)

    Were their discharge curves different? (voltage under load)

  28. #28

    Default Re: Japanese Vs Chinese Eneloop Cycle Testing Results

    Quote Originally Posted by Power Me Up View Post
    A good question that comes to mind is the fact that the IEC standard that is referenced on the back of the Eneloop packs would take around 18 months to get through 2100 cycles. How on earth have they managed to test the Chinese cells to that many cycles using that method when production in China has only been going for 12 or so months????
    I'm guessing that the plant must have made cells for other brands for a while but other LSD brands that I've seen only rate 500 cycles.

    I can only assume that Panasonic did not test the cells at all and just took all the blurbs from the last 4th gen Eneloop from FDK but not the technology. Mind you, the first gen Eneloops are not bad.

    Quote Originally Posted by bcwang View Post
    Were their discharge curves different? (voltage under load)
    I'd like to know too.

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    Flashaholic* SimulatedZero's Avatar
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    Default Re: Japanese Vs Chinese Eneloop Cycle Testing Results

    I'm not going to lie, this does not sit very well with me at all. Damn, and I thought I had found the Holy Grail of deals on Amazon for rebranded Eneloop XX series. The batch that I got is all made in Japan, but who knows now.

    A big thing to me though is the discharge curve. Like a couple of others have mentioned, I would like to see that plotted out on a graph for comparison.
    "Maybe you should just stick to fire on a stick... it's received excellent reviews here - plus it's a time tested design..."

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    Default Re: Japanese Vs Chinese Eneloop Cycle Testing Results

    Quote Originally Posted by bcwang View Post
    I noticed for the first 200 cycles or so, the Chinese Eneloops had more capacity? Was this due to being charged fuller due to termination behavior differences? (which may reduce cycle life). Or maybe having slightly higher capacity degrades their life cycle performance. (something possibly seen in the eneloop XX vs turnigy comparison.)
    The Chinese Eneloops had more capacity at the start - you're quite possibly right that it is related to the reduced cycle life.

    Were their discharge curves different? (voltage under load)
    Good question!

    I've done a couple of graphs up:





    Both of the above graphs were done for the 3rd (2A) discharge for both cells - voltage under load was noticeably lower during the first discharge and improved a little with the 3rd discharge compared to the 2nd.

    It's interesting to note that the Chinese Eneloop wasn't able to maintain the same voltage as the Japanese cell - although the Chinese Eneloop had more capacity, the total energy discharged at 2 amps was about the same. Internal resistance as measured on the charger for those discharges was 30 milliOhms for the Japanese cell and 50 milliOhms for the Chinese cell. IR varied a bit over the cycling, so there wasn't always that much difference between the IR of the 2 cells. At lower discharge rates, I would expect that the Chinese cell would pull ahead on Energy, but at higher currents, the test would favour the Japanese cell.

    The above data was taken from the first pair of cells. I just took a look at the data from the second set of cells and the differences are actually bit smaller - to the point where the Chinese Eneloop has about 50mWh more energy than the Japanese cell - still a lower voltage under load, but less pronounced. The IR values are also closer at around 34 milliOhms and 45 milliOhms. I'm not sure of the reason for the differences - could be individual cell variations, or a bit more contact resistance on the first Chinese cell...
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