Eneloops left in charger indefinitely

[walkngdude]

Hi all,
Can you tell me if it's safe to leave eneloops in the charger until they are needed? I have the charger that came with the Eneloops from Costco and it's nice to leave the batteries there so my wife can easily grab a fresh one before her morning run with her Fenix L1D.

I also have a La Crosse Technology BC-900 in my office that has a few Eneloops in it most of the time also for my Nitecore D10 and Fenix L0D. Is this something I need to worry about?

Also I'm looking to buy a much brighter light and am considering something like http://www.candlepowerforums.com/vb/showthread.php?t=214238 and AW Protected 18650 batteries and some fancy charger.

I'm not sure if I know what an 18650 is. I've been doing some reading but get a little crossed up now and then. I gather that a 18650 is a li-ion and needs greater care in handling like don't leave it on the charger after it has charged. Also I'm thinking that one of these will replace two cr123s and vies versa so when I take the family camping and have no AC power source I can bring a bag of cr123s and have the light all week.

Thanks for feeding the nube and I promise to keep reading.

Marc

 

[buickid]

18650 designates a common size for lithium batteries.
It breaks down like this:
18 65 0
18mm wide, 65mm long, 0 for a round cell.

123 size batteries are 16340, 16mm wide, 34mm long

One 18650 will replace two 123/16340 sized cell size wise, but the question lies in the voltage. A primary (non-rechargable) CR123A cell is 3.0V with no load, and drops to something a bit lower when loaded. A rechargable lithium battery sits at around 4.15-4.20V fresh off the charger, and is considered dead at 3.7V. A light designed for 2 CR123 batteries is looking for 6V, but one 18650 will give it only 4.2V. If you use two 16340 batteries, then its going to be getting 8.4V!
So the question is, which light are you looking at? Some lights designed for CR123 batteries will run fine when using 16340 rechargables, others will not regulate the brightness properly (wont dim), while others will fry.

Regarding your Eneloop question, a good charger should cease charging once the cell is full, in which case leaving the cells in the charger should be fine. I don't own or have experiece with the two chargers you mentioned, so I can't comment on their workings. Since the Eneloops are LSD (Low Self Discharge), even if you take them off the charger, they will maintain their charge for quite a while, unlike other Ni-Cd/MH batteries.

Hope you found this helpful and not more confusing! :thumbsup:

 

[Marduke]

Eneloops have a very low self discharge, meaning they can sit on a shelf for months and months and still hold onto most of their capacity. There is no need to leave them on a trickle charge. In fact, long term exposure to a trickle charge will eventually destroy a cell.

 

[Black Rose]

One 18650 will replace one 123/16340 sized cell size wise,

Correction: One 18650 will replace two 123/16340 sized cells, however a 17670 cell directly replaces two 123/16340 sized cells but has about 800 mAh less capacity than an 18650 cell.

 

[Turbo Guy]

The OP specificly asked about Eneloops and stated he uses a BC-900 , given thaose facts I agree that it is best to remove the cells after they have completed their charge however a few hours to a day extra spent on charge is not a big deal IMO. I would be more concerned with an overcharge due to the charger missing the peak detection overcharging/heating the cells and continuing this cyle until noticed and stopped.

Now when it comes to NiMH cells in general it is best to charge right before use and not try to stock pile a bunch of charged/ready to go cells.
Even some of the listed as LSD cells are not so great at retaining their charge. I have limited experience with some LSD AA NiMH cells which have a self discharge greater than many standard(non-LSD) cells. If I charged these cells and expected them to be mostly still charged in a few weeks I am afraid I would have a lot of mostly dead cells. With cells such as these a constant slow/trickle charge such as provided by the BC-900 could in fact atleast keep them mostly charged and there is little harm that can be done to them anyway.

Much has been made over the years of the harm done by constant trickle charging of NiMH cells. Well I have a 6 plus year old cordless phone which has a 3cell 900 mAh AAA battery in it. This phone has allways been an extra and while allways conected rarely gets used. If I think about it I take it out of the cradle for a day or two every six months to a year. The battery in it has a 2002 date code and it still does just fine. To me this is rather good performance as most AAA cells are not great performers to begin with.

 

[Black Rose]

Even some of the listed as LSD cells are not so great at retaining their charge. I have limited experience with some LSD AA NiMH cells which have a self discharge greater than many standard(non-LSD) cells.

Would those cells happen to be the Tenergy R2U LSD AAs?

 

[Turbo Guy]

Titanium Enduro 2100

 

[TakeTheActive]

...Can you tell me if it's safe to leave eneloops in the charger until they are needed? I have the charger that came with the Eneloops from Costco and it's nice to leave the batteries there so my wife can easily grab a fresh one before her morning run with her Fenix L1D.

I also have a La Crosse Technology BC-900 in my office that has a few Eneloops in it most of the time also for my Nitecore D10 and Fenix L0D. Is this something I need to worry about?

From SilverFox's Sig Line:

Most batteries don't die - they are tortured to near death, then murdered...​

Is it safe? A 'qualified' YES. Any electrical device can fail and possibly cause a fire. Is it convenient? YES. Are the majority of rechargeable battery users doing it? PROBABLY. Is it 'Best' for the cells? NO.

The majority of rechargeable battery users probably don't know about 'matching cells' either and replace all 2 or 4 cells in their digital camera when one fails.

IMO, only a fraction of the rechargeable battery users read this forum. And, of that fraction, even fewer follow all the 'Rules'. If you want to know the 'Best' way to treat your cells, read SilverFox's posts (CLICK on my Sig Line LINK for my favorites). Then, decide for yourself how much effort you're willing to invest.

...Also I'm looking to buy a much brighter light and am considering something like http://www.candlepowerforums.com/vb/showthread.php?t=214238 and AW Protected 18650 batteries and some fancy charger.

I'm not sure if I know what an 18650 is. I've been doing some reading but get a little crossed up now and then. I gather that a 18650 is a li-ion and needs greater care in handling like don't leave it on the charger after it has charged. Also I'm thinking that one of these will replace two cr123s and vies versa so when I take the family camping and have no AC power source I can bring a bag of cr123s and have the light all week...

I've been using NiCDs and/or NiMHs for 20+ years and I personally haven't had any reason to invest in yet another technology (batteries and charger), so I cannot answer your Li-Ion questions. I'm also not that interested in flashlights so I wonder if there are 1, 2 (or more) cell AA flashlights available that would also suit your needs (and you could bring along a bag of Eneloops).

 

[alfreddajero]

Once the cells are done you can leave them on the charger for 2hours and then take them off......but for the most part i like to have a home to go too.......especially if i left batts in the charger and then something happened while i was gone. The wife would divorce me and then kill me. (good thing homeowners insurance is paid up)

 

[buickid]

I'm guessing the BC900 continues to trickle charge after it says its complete.

Does the Maha C9000 do the same?

 

[alfreddajero]

yes it does.

 

[Bullzeyebill]

walkngdude, was your Eneloop question answered to your satisfaction. The consensus is to take your batteries off the charger when they are through charging, thought you can leave them on for awhile, before taking them off. Keeping them on indefinately will harm them in the long run. Are you planning to do that what we recommended?

Bill

 

[Black Rose]

Titanium Enduro 2100

You must've gotten some duds.

I have 8 of those and have not had any serious self discharge problems with them at all.

 

[Mr Happy]

You must've gotten some duds.

I have 8 of those and have not had any serious self discharge problems with them at all.

He might have turned them into duds by leaving them on the charger indefinitely...

(I know, I know, Turbo Guy is not the one asking the original question )

 

[Turbo Guy]

You must've gotten some duds.

Lucky for me I only purchased 16 of them and they were on sale after all..



Same cells as here

http://www.candlepowerforums.com/vb/showpost.php?p=2896771&postcount=97

After 15 cycles I figured they were not going to get any better. I let them set for a week and was greated by remaing capacities all over the place.
Charged them all back up and will check capacities one more time before deciding if they get tossed or what.

 

[alfreddajero]

I know that this is not part of the OP's question but i have 12 and they are well over 2100 rated capacity, at least the ones that i have.

 

[walkngdude]

walkngdude, was your Eneloop question answered to your satisfaction. The consensus is to take your batteries off the charger when they are through charging, thought you can leave them on for awhile, before taking them off. Keeping them on indefinately will harm them in the long run. Are you planning to do that what we recommended?

Bill

Yes Bill and all the rest of you fine fellows your comments were very helpful, thank you. I took the batteries out of the chargers and put them in a little Tupperware thingy next to the wife's Fenix. I just hope she doesn't get a bad cell or throw a used one back in the charged box. She runs for an hour or so before dark two or three times a week sometimes she has to cross under deserted railroad trestles and through some remote forested areas and I just heard a story on NPR about a woman jogging a trail and was attacked by a rabid fox. The thing latched on her arm and she knew she had to bring it in for testing so she jogged four miles back to her car with a snarling, mouth foaming fox gnawing on her arm, threw it in the trunk and took it to the hospital.
I just got the wife comfortable with switching the cells from the charger to the light before she goes outside and told her to look for the eye reflection in the brush. My wife is very smart but a woman's priorities are 240 degrees out of phase from a man's and adding another step in the battery chain might be just the thing to start a disastrous chain of events.
But if you guys are all right with this call I guess I am too. I'll let you know what happens.

Thanks
Marc

 

[Marduke]

Have a two-compartment box, or two boxes. Label one for "used cells" and the other "fresh cells". You deal with keeping up with them, and she should (hopefully) be able to manage what to do on her end.

 

[Beacon of Light]

Eneloops have a very low self discharge, meaning they can sit on a shelf for months and months and still hold onto most of their capacity. There is no need to leave them on a trickle charge. In fact, long term exposure to a trickle charge will eventually destroy a cell.

And you thought we'd never agree on anything.