Thanks. I saw them in another post since I wrote that. I haven't bought any yet but it's only a matter of time...
Thanks. I saw them in another post since I wrote that. I haven't bought any yet but it's only a matter of time...
Is there a FAQ for LSD batteries around here somewhere describing the benefits/drawbacks of LSD batteries? The topic is not listed in the Welcome Mat,
I just bought the Costco blue box of Eneloops and am trying to figure out which situations I should use them and when I should use my high capacity Powerex 2700mAh NiMH batteries.
As a caver, I take my batteries very seriously because I must carry a lifetime supply of batteries with me when I go underground (enough batteries to provide enough light for me to exit the cave before I die lost in the dark).
I spend a couple of days charging and testing my batteries before each trip and use the Powerex NiMH batteries because they have the highest real-world capacity on the market. As nice as the eneloops are for maintaining their capacity, I am disappointed by the loss in total capacity when compared to freshly charged high capacity NiMH
So my questions is this: If slow discharge is not really important for me when I am caving, are there other reasons that I still might choose the eneloops for my purposes?
Or should I just use the eneloops in devices such as remote controls and the bedside/glovebox flashlights around the house that are less critical and are used rarely or minimally over many months where the LSD properties make them more convenient?
Hello Yucca Patrol,
The Eneloop cells offer higher voltage under load, low self discharge rates, and higher cycle life. If those features are not a benefit to you while “underground,” you will have to choose other uses for those cells.
Behind every Great man there's always a woman rolling her eyes...
Most batteries don't die - they are tortured to near death, then murdered...
I have a few routine uses for Eneloops that are perfect for them. We run a couple radios and a small FM transmitter that were a real PITA to try to keep fed with regular NiMH cells. The difference is breathtaking. I also have a tiny 3xAAA headlight that I only use for a few minutes once or twice a month. When I ran it of NiMHs it was either dead or near death almost every time I needed to use it. The Eneloops have changed it into a whole 'nother device.
I'd imagine that everyone will be different but many NiMH users will have at least a few devices that don't draw much and yet seem almost impossible to keep NiMHs in.
From the reading I've done here and at batteryuniversity.com, NiMh cells like a strong charge current ranging from half capacity to full capacity (for a 2000 mAh cell, a charge rate of 1000 mA to 2000 mA is ideal). If I only knew then what I know now...
My Rayovac PS16-B charger is a 4-6 hour charger. As it stands right now, the break in cycle on my new Maha MH-C9000 is showing that I have 8 AA NiMh cells that appear to have been ruined by the Rayovac charger.
I have four more cells undergoing break in right now, and am expecting the same results.
Don't take my word on that - I'm a noob when it comes to this stuff. I've learned a lot from this site in the couple of weeks I've been here, but I am still learning.
Maybe SilverFox or Mr. Happy will chime regarding your Maha 604 and your LSDs.
Most chargers "work" - obviously -
otherwise they wouldn't still be on the market and still selling.
So your Maha charger - will continue to work the same way it had been working with NiMH previously - and Maha makes good chargers.
The fact that the charger takes more than 6 hours to charge - suggests that it is about C/5 charge current - maybe 400-500mA range(?) - this is not bad in itself - NiMH can be charged with almost any current within reason.
The main problem with charge currents in the range of C/10-C/3 is that the end of charge is hard to detect accurately which may lead to overcharge and overheating - which are the two things that shorten the life of NiMH -
However, it's unlikely to be instant death - but a gradual but quicker decline in the battery's performance - the common symptoms are the inability of the battery to supply higher currents, or loss of capacity, and for normal NiMH the inability to hold a charge for more than a few days.
Overcharge and overheat conditions are more likely to occur if one depends on the charger to terminate properly with a battery that is mostly or partially charged - because the end of charge indications are harder to detect - the battery is more likely to be overcharged which leads to overheating.
Good chargers tend to have backup safety terminations like peak voltage and/or temperature sensors to cut off the charge when any of these are exceeded - your Maha 604 may have these - check your specs. So the likelihood of overcharge is lessened - but with older batteries the charger may cut off incorrectly - leaving the batteries either with an incomplete charge or overcharged.
The main advantage of a charger with the charge current range in the C/2-1C range is that the end of charge signal (-dV) is easier to detect - and batteries are charged close to full and not overcharged.
For the current LSD batteries in the range of 1900-2100mAh - this means the charger ideally should have a charging current in the range of 1050-1900mA or 1.05A-1.90A.
Note: I am not a battery or charger expert - I read and take in articles and posts from the more knowledgeable too.
There seems to be some debate about this whole fast charge vs. slow charge thing.
I think the short answer is, "don't sweat it".
The longer answer is more involved.
Do NiMH cells really like a strong charge current, or is it actually better for the charger this way? The argument goes that higher charging currents give a better end of charge signal, so less chance of missed terminations and consequent damage from overheated batteries.
Of course, if you do get a missed termination at higher charging currents then the overheating problem is much more severe. At lower currents heat is less of a problem. I have tried charging Eneloops on a timed charge at 400 mA beyond the fully charged point and they don't seem to get that warm at all. In fact, I almost wonder if a 6 hour timed charge at 400 mA is an optimum charge for Eneloops. (Especially since the label on the very similar Uniross Hybrios says "charge at 420 mA for 7 hours".)
In Sanyo's Eneloop Q&A, I believe they advise using more moderate charging rates for Eneloops too. Subjectively, one has to feel it is kinder to the batteries to use lower rates.
One other point sometimes mentioned is that persistent use of slower charging might reduce the high current delivery capability of the cells. I think however that Eneloops are too new to know if this could apply to them.
So I would feel happy using a slower charger. I own and have tested the Duracell Power Gauge charger that takes 4-5 hours for Eneloops and it gives them a reliable 100% charge every time without heating up the cells. I can't say if there would be a downside to this over the longer term, but it will be years before I have gone through enough charging cycles to find out.
Incidentally the Energizer Compact Charger is described as having intelligent end of charge detection, and the user manual says it will not harm batteries to leave them in the charger after they are charged. It also indicates a charge time of 4-5 hours for 2000 mAh cells.
I guess it seems like the Energizer Compact Charger will work fine with LSDs....say Rayovac Hybrids. That's good to know.
And really, at $8 for 4 AAs, Rayovac Hydrids are not that expensive to start. Actually, I was surprised how cheap they were at Walmart.
Actually at 2 of the local WalMarts they seem to be out of RoV Hybrids - either the 4x batteries packs, or the introductory 2xAA, 2xAAA and cheap charger pack (with the $5 off coupon) -
contrast this with the plentiful regular RoV NiMH (see RayOVac NiMH AA (NM715) ) - so supply from RoV probably may not be a problem - could WalMart be phasing out the RoV Hybrids?
BTW - if the Hybrids are still closer to the $9 mark -
Kodak Pre-Charged LSD batteries are $7.88/4 at WalMart - they are normally displayed with the digital camera accessories like flashcards etc.
Personally I would rate eneloops - as they are the most well known and seem to be the standard other LSDs are judged by - the "best" - but by only a very slight margin - then the rest (excluding re-badged eneloops) aren't that far behind. The Kodak Pre-Charged seem to have been tested with noticably higher mAh capacity. But eneloops and Uniross Hybrios seem to maintain high voltages - which may be important for voltage sensitive equipment using multiple AA's.
(eg: my Pentax K100D dSLR is very battery fussy, and I feel that eneloops probably will do better in it than Kodak Pre-Charged, as the Kodak P-C may drop their under-load voltage level quicker than eneloops - to below the camera's cut-off, shutting off the camera when there may be still charge left in the batteries - Caveat NOTE: I have not done any actual comparison test on this, so it is still conjecture/hearsay/guessing on my part)
Eneloops seem to be pretty rugged.
I just finished a series of flashlight tests which required discharging batteries at a moderately high rate for 5 or 15 minutes. Then I topped the batteries back up with a Maha MH-C9000 charger and used them for additional tests. Well, somewhere along the line when topping off from the recent shallow discharge, the charger missed the end-of-charge voltage drop for one of the AAA cells. At a charge rate of 400 mA (C/2), the cell got warm but not really hot, so whatever temperature shutoff the charger has wasn't triggered either. When I discovered the problem, the indicated total charge was over 2300 mAh, or nearly three times the cell capacity. After a couple of hours rest, I checked the cell capacity by discharging it and found it to be fine. So the cell apparently didn't vent. I imagine the elevated temperature might shorten the cell life somewhat, but otherwise it doesn't seem to have been bothered by the abuse.
I was considering high capacity cells for my own caving trips, but I only do a handful of trips a year, and whatever cells I bought would get used far more for other tasks back in the real world, not off adventuring underground. A high priority was getting something rugged, that would last a lot of cycles and be able to tolerate occasional abuse, and simply be ready whenever I wanted to use them without having to recharge immediately beforehand. I also wanted to standardise on just one type of cell, as my devices use 2, 3, or 4 cells, so it's nice to be able to mix and match. I've found Eneloops to be very consistent in capacity.
So for me Eneloops are used caving and around home. I don't miss the extra capacity.
FWIW my present main caving light on low power with a set of Eneloop AA cells gives me a bucket load of light and about six regulated hours. My longest trip so far has been less than five and a half hours, so if I don't use high much I won't have to change mid-cave. Of course I take a spare set, plus a set of fresh alkalines. If I wanted to double my run time I'd just slap another 3 cell battery holder on my helmet - I don't find the weight a problem.
Delkin are now marketing a LSD rated at 2300mAh -
(from xcel730 in this Post)
I think this is one of the first LSD that's been rated >2100mAh.
Delkin page on the 2300mAh LSD
Note: also the life cycles claim at 600 - different from the more common 500 (Yuasa) or 1,000 (eneloop & re-badges).
The only place I can find selling these (other than Delkin) is Thomas Distributing
EDIT to ADD -
Only just found out Tenergy have an LSD also rated at 2300mAh -
please see this thread -
Tenergy vs Eneloop (AA and AAA) 30 day self-discharge
I'd make the observation that those Delkin cells look rather similar to the 'fake' UltraLast Hybrios and the Powerex Immedion cells: they have the dome-shaped button and the valley around the top by the plus sign. Both Hybrio and Immedion cells are claimed 2100 mAh.
I have some of the UltraLast Hybrios and they are testing consistently at around 1870 mAh. Until someone tests the Delkin cells, I would hold back on believing the 2300 mAh claim.
Regarding the cycle life claims, remember that the numbers like 500 or 1000 are not exact. The cycle life you can expect depends on how you define the end of life point, on variations in manufacture, on the conditions in which the cell is charged, stored, and discharged, and on a great big bunch of hand-waving. For practical purposes I would consider cycle lives of 500 and 1000 to be effectively the same.
Post #5 (link) in the thread - Slowest Discharge AA and AAA Nimh please?, I cant decide at forums.all-battery.com has an overview comparison of eneloops, RoV Hybrid (and Uniross Hybrio - which the poster says are the same as RoV, but please also see the thread by Mr Happy Uniross Hybrios are Eneloops...? ), Maha Imedion, Tenergy ready to use [R2U]
The post is by Tom Veldhouse who seems to do a lot of battery testing - the link to his profile shows some of his postings (or all his posts ).
EDIT to ADD - another review of eneloops - seems pretty thorough -
Electronics - Review: Testing Sanyo's Eneloop Rechargeable Battery ...
I see the self-discharge graphs by archae86 in AA and AAA NiMH low self-discharge tests--Round 2 over at dpReview that mishoo posted in #132 has been updated to show the full 3 months.
The best performing LSD AA was the Maha Imedion (IME), followed by the Kodak Pre-Charged (KPC) and GP ReCyko (GRY) - the KPC and GRY curves seemed very similar - almost overlapping. Graphs for AA LSDs
The graphs were hard to read because they were so close together
- this kind of brings me to make a comment that probably for most practical purposes - these LSD batteries would be pretty similar in performance. Although it's "interesting" that all the graphs seem so similar, there were almost no crossovers ie: if a battery tested with higher capacity it maintained the higher capacity over the full 3 months......
So for now it seems pretty safe just to buy almost any LSD brand - except obviously if one hears of poor performance from any - eg: some varients of the UltraLast Hybrio.
I would still regard eneloops as the benchmark - and best of breed by reputation and what I have read - but there were several other brands of LSDs in that test that seemed to show slightly better than eneloops (including the RoV Hybrid (RHY) - however, SilverFox's tests in Eneloop Self Discharge study showed the opposite)
In the AAA LSD graphs - the GP ReCyko AAA (GR8) came top, followed by the Maha Imedion AAA (IM8), then almost overlapping eneloop AAA (EN8) and Duracell Pre-Charged AAA (DP8) (this latter is not surprising, since made in Japan Duracell Pre-Charged are suspected re-badged eneloops). Again the graphs are "interesting" in that they are so similar in shape and without any crossovers.
Since the Kodak Pre-Charged and GP ReCyko AAs are so similar could KPC be re-badge of the GP ReCyko?
This also gives rise to speculation that the AAA may be similar re-badges?
I have noticed that WalMart is now carrying AAA Kodak Pre-Charged 2-pk @ $3.96.
PS - Wikipedia now has a separate entry for Low self-discharge NiMH battery - they now note:
" This new type of batteries is marketed with over a dozen different brand names, but only actually made by three companies – (Sanyo, Gold Peak and Yuasa). "
Gold Peak Group are the manufacturers for GP ReCyko -
so I wonder if the Kodak Pre-Charged are made by them?
Is anyone here have use the Eneloop Size C and D they released in Japan Sept 12, 2008? Just wondering how is the performance for Eneloop C and D. Mind to share your experience here?
As far as I know, they have not been released yet in North America.
I figure Costco will be one of the first places these will show up once they are released in North America.
Msg deleted. Sorry that I mistaken press 2x times here. Hopefully got some sharing about Size C and D later.
For what I do with 'em Hybrids work as well as Eneloops.
I only HAVE 4 eneloops so I can't say for sure when it comes to multi AA lights, but 6 or 9 Hybrids light up my hotwires just peachy.
I have 8 Kodaks and a few of them either grew bigger or the labels shrunk. And they look goofy but still run my GPS all day.
Someone else has probably already posted this somewhere, but in case they haven't...
"SANYO Announces C- and D-sized ‘eneloop’ Batteries and Universal Charger"
Press release: http://www.sanyo.com/news/2008/08/08-2en.html
C = 3000 mAh
D = 5700 mAh
Charger is for all four sizes. I haven't read through enough to say if it's individual channels, yet.
anyone learned who offers the "c" and "d" cells yet? Gotta get some to run my new Triple LED from Malkoff in a Maglite
I think Sanyo did a cheap hack with these cells.
C - I can't argue much (although it is very low to EnergyON C size 4500 LSD cell). It better have one hell of a low discharge rate with 1.5 Ah penalty over EnergyON
D - probably inside of the casing we will find 3 Eneloop AA batteries in parallel. Since most of my Eneloops are around 1950 to 2050 mAh the D's rating of 5700 is good fit 3x1900. EnergyON D cell is 10000 mAh.
Did anyone performed discharge rate tests on C and D EnergyON cells?
Good LSD C's would make one of my lights
MUCH more useful!!!