# Best way to maintenence Eneloops?



## Danne71 (Jun 2, 2009)

Hello, i´m from Sweden and this is my first post on this exellent forum.

I have a lot of Eneloops and i wonder what is the best way of taking care of them. I use them in all my equipment from remotes to gps´s.

When i bought them 2 years ago i did a break in on all of them on my c-9000 and they all had 1920-1950 Mah. Since then i have just charged them and used them.

Last night i ran a Charge/Discharge (1000Ma. charge+topoff/400 Ma. discharge)on them and they had "degraded" to 1820-1850 Mah. I know this isnt mutch but its a little sign of poorer performance. I tried two R/A on them but it didn´t improve the performance.

So my question is:
Should i do another break in on the batteries or should i wait for the batteries to get even lower performance. I´m afraid that i might stress the batteries if i do a break in just after 7 charges (even if they are two years old i have just charged them around 7 times). The manual says its recommended to do a break in every 30 charges.

Is it healthy to do a break in just after a small sign of degraded performance, or is it healthier to save the break in´s to when the batteries reach like 1650-1700 Mah?


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## Niconical (Jun 2, 2009)

They may have only done 7 charges, but if that was over 2 years they spent quite a lot of time doing nothing at all.
Put them through the break-in again, it will do them good 

EDIT: Just thought I should clarify. That time spent doing nothing over the 2 years is exactly the reason for the break-in. Although the eneloops will of course still work after 1 year (or even 2), inactivity does build resistance, hence the break-in will help.


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## Black Rose (Jun 2, 2009)

As Nic said, do a break-in cycle on them and it should restore their performance.

I've got a bunch I need to give a break-in, or at least a couple cycle mode runs. I need a second C9000


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## Danne71 (Jun 2, 2009)

Thanks!!

I have them on break in right now.


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## Danne71 (Jun 4, 2009)

I was thinking.....

Because i don´t charge my batteries too often, i could use the break-in mode every time i charge them. I could use a timer so it don´t discharges after 16 hours.

I have read that Tom (SilverFox) thinks this is the gentliest way to charge your batteries. According to him you allways get the fulliest charge this way and the longest cycle life too.

I shure got the time to charge my batteries this way.

Mabey SilverFox could anwer this question to me???

Sorry for my english!!!!!!


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## TakeTheActive (Jun 4, 2009)

Danne71 said:


> ...*I have a lot of Eneloops and i wonder what is the best way of taking care of them. I use them in all my equipment from remotes to gps´s...*


Do you 'Assign' a battery to a specific device or do you randomly move them around? AFAICT, 'Device Discharge Current' directly affects HOW you want to maintain the battery, ESPECIALLY if it's getting INFREQUENT charges.



Danne71 said:


> ...When i bought them 2 years ago i did a break in on all of them on my c-9000 and they all had 1920-1950 Mah. *Since then i have just charged them and used them...*


For 'Daily Use' batteries, 'Charge-and-Go' with the occasional 'Break-In' and/or 3-5 'Refresh-and-Analyze' cycles works fine. For 'Low Discharge Current / Infrequent Usage / Storage Box Queens', special care is required.



Danne71 said:


> ...Last night i ran a Charge/Discharge (1000Ma. charge+topoff/400 Ma. discharge)on them and they had "degraded" to 1820-1850 Mah. I know this isnt mutch but its a little sign of poorer performance. *I tried two R/A on them but it didn´t improve the performance...*


ONE / TWO 'Refresh-and-Analyze' cycles?!? How about trying a 'Break-In', then 3-5 R&As.



Danne71 said:


> ...So my question is:
> Should i do another break in on the batteries or should i wait for the batteries to get even lower performance. *I´m afraid that i might stress the batteries if i do a break in just after 7 charges (even if they are two years old* i have just charged them around 7 times). The manual says its recommended to do a break in every 30 charges.
> 
> Is it healthy to do a break in just after a small sign of degraded performance, or is it healthier to save the break in´s to when the batteries reach like 1650-1700 Mah?


Rechargeable batteries are like the muscles in your body - *USE 'EM OR LOSE 'EM!*

And your batteries are atrophying! :sick2:

CLICK on my Sig Line LINK and read the articles in the '*Rechargeable Battery*' section. Bottom-line is you have a bunch of NEGLECTED 'Storage Box Queens'. If you want VIBRANT cells, you need to USE THEM. If you don't have enough devices that are using them, CYCLE THEM.

If you figure on a 10-year lifespan with ~500 cycles, that's roughly one recharge per week. With seven recharges in two years, what are you saving them up for? 35 recharges in 10 years and they're DEAD ANYWAY! Plus, at a MUCH REDUCED average capacity.

*My Opinion: *

You can either assign each cell to a device and maintain it according to the device's current draw.

*OR*

You can enforce a STRICTER (i.e. Quarterly) '3-5 R&A Cycles' and/or 'Break-In' routine for EACH cell so that ANY cell you choose will be equally VIBRANT.

*NOTE: *Excessive use of the term 'VIBRANT' due to *SilverFox* influence! :tinfoil:

[This post can go '_on-and-on-and-on_' so please invest a few hours reading the LINKs I've assembled and THEN come back with any further questions.  ]


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## Yoda4561 (Jun 4, 2009)

I usually use the c9000's default charge as needed, and a discharge+break-in cycle every 6 months or so for good measure on all of them.


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## Danne71 (Jun 5, 2009)

What is the point of buying lsd batteries if you cant store them? I thougt charging them every 3-4 month made them vital. Sanyo says it holds 85 procent after one year. They should have put a warning that storing a eneloop this long could harm the batteries. Is there any evidence that storing a eneloop for a couple of months is not good for them? I mean they havent been on the market long enough for this to be tested.


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## Yoda4561 (Jun 5, 2009)

It doesn't harm them, but you're only going to get 90% performance out of them instead of 100% after a couple years. It's fine if you just do the discharge-breakin every few years, they'll pick right back up. Some folks just like to keep things in top condition.


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## SilverFox (Jun 5, 2009)

Hello Danne,

Welcome to CPF.

Normal NiMh cells should be kept working in order to stay in very good shape. When you don't use them, they gradually oxidize from the inside and loose capacity.

With normal NiMh cells, you would store them discharged, and run a charge/discharge cycle on them every 30 days. This keeps the cells vibrant.

With cells that are in constant use resulting in several charge/discharge cycles every week, it is recommended to do the 16 hour 0.1C charge every 20 - 30 cycles. With cells that are in storage that you are doing monthly charge/discharge cycles on, it is recommended to do the 16 hour 0.1C charge yearly.

With the introduction of the low self discharge NiMh cells, we are still trying to figure out the best way to care for them. I just put some AAA Eneloop cells into service, and they had been stored with no attention since 2006. I did a discharge, then ran the Break-In cycle in the C9000. They are doing just fine. I don't have a lot of spare cells, but I am tending to ignore my Eneloop cells. I make sure there is some charge on them, then let them sit until they are needed.

While you are seeing some degradation in capacity with your cells, they still are at around 95% of their initial capacity. I would just continue to use them until the capacity dropped to below 90% of their initial capacity. Then you can do another Break-In cycle on them.

With that said, if there are no time constraints feel free to use the Break-In charge portion as your normal charge. You don't have to go through the whole charge/discharge/charge cycle, but can set a timer and stop the process after the initial charge. There is no problems with going through the whole cycle, it just takes a little more time. When you go through the whole cycle, you do get numbers for comparison so you will have to decide if those numbers are important enough to spend the additional time running the whole cycle.

Tom


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## hotlight (Jun 5, 2009)

quick question: 

is the "break in" on the Maha c9000, the same as "Refresh" on the BC-900?


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## Black Rose (Jun 5, 2009)

No it isn't.

The C9000 doesn't really have an equivelent of the BC900 Refresh mode.
The closest would be Cycle mode.


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## Danne71 (Jun 5, 2009)

Ok. I think i was wrong to begin with. My numbers in the first post was after a regular charge at 1000 mah. After i did a Break-in they come in at 1900-1950 Mah. So i think my cells are completely healty.

Thanks to everyone for helping me!!!!!!!!!!!


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## thedeske (Jun 29, 2009)

This looks like a great place to post a question rather than start a new thread.

I have a Maha 9000 and 20 Eneloop AA on the way.
16 will be dedicated to an 8 cell light I plan to buy soon and the others are backup to to 8 cells I have in use.

The break-in routine looks like 1 day per 4, so I have 7 or so days of break-in ahead at a casual pace for the 28. Any reason not to prep the entire 28?

Half the cells will sit in a drawer as backup. The lights get the most use, but AAs in the shop cycle every 6 months or so (5-7 cells in a large clock, laser level, digital fence)

I'm guessing the El Cheapo Eneloop 2 channel (NC-MQN06U) that came with the first 8 is keepable as a backup. Doesn't take up much space in the drawer.


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## Mr Happy (Jun 29, 2009)

The most important reason to run a break-in cycle on eneloops is for high drain, high power uses. For low drain uses it is not likely to make much observable difference to performance.


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## thedeske (Jun 29, 2009)

Mr Happy said:


> The most important reason to run a break-in cycle on eneloops is for high drain, high power uses. For low drain uses it is not likely to make much observable difference to performance.



thanks


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## travelinman (Jun 30, 2009)

It sounds like people are collecting cells and have waay too many. Our use of NiMH cells shows exactly what has been discussed here. Have just enough that you can use them regularily. Any "extras" that you have, give them away to people that can use them regularily.

Like taketheactive says "use em or lose em".

Hot light, the refresh cycle on the BC 900/700 actually tests each cell by charging it up, then discharging and noting the capacity, then it does it again and compares the capacity with the last cycle. It continues these cycles until it see no further gain in capacity. It's a great way to refresh your cells.

I use it all the time and rarely use more than 200 ma charge (the default). I have the time, its a perfectly safe machine, just set it up and let it run. Go have fun while it's taking care of business.


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## TakeTheActive (Jun 30, 2009)

*SLOW Charge Rate Is Not Always BEST Charge Rate!*



travelinman said:


> ...*the refresh cycle on the BC 900/700* actually tests each cell by charging it up, then discharging and noting the capacity, then it does it again and compares the capacity with the last cycle. It continues these cycles until it see no further gain in capacity. It's a great way to refresh your cells.
> 
> *I use it all the time and rarely use more than 200 ma charge (the default). I have the time*, its a perfectly safe machine, just set it up and let it run...


*Don't be lulled into the false security that 200mA is always 'safe' and/or 'best'.* As cells age, they need more current to insure a positive -DeltaV termination but not too much current to cause excessive heating due to rising internal resistance.

Try this experiment, ESPECIALLY on older cells (skip Step#4 on AAA cells). Instead of REFRESH, or TEST (which only display Discharge capacity): 
Do a DISCHARGE @ 200/100 and note the final 'Accumulated Capacity'. 
Do a DISCHARGE @ 500/250 and note the final 'Accumulated Capacity'.
Do a DISCHARGE @ 700/350 and note the final 'Accumulated Capacity'.
Do a DISCHARGE @ 1000/500 and note the final 'Accumulated Capacity' (watch for overheating).
Compare the results. If the result from #1 is way higher than the others, it missed -DeltaV termination and overcharged (usually without overheating). 

Here are some examples. The missed -DeltaV terminations are obvious.

Note, I preceed the recorded capacity with a '*+*' to denote '*Accumulated Capacity*' (Charge *IN*) vs '*Available Capacity*' (Discharge *OUT*):

```
Sears DieHard 1300mAh AA NiMH    |   #1    #2    #3    #4
---------------------------------+---------------------------
06/30/09 C9000 Cycle3:   600/ 100|  979   974  1099   960 mAh
06/xx/09 C9000 Cycle2:   600/ 100|  981   992  1104   969 mAh
06/xx/09 C9000 Cycle1:   600/ 100|  970   988  1112   957 mAh
06/27/09 C9000 Discharge:  300   |    0    13    44    15 mAh
06/27/09 C9000 Impedance Check:  | 1.74  1.78  1.59  1.75 VDC
06/16/09 BC900 Discharge:  350   |+1204 +1289 +1234 +1180 mAh
06/15/09 BC900 Test:  200/ 100   | 1100  1061  1165  1120 mAh
06/15/09 BC900 Discharge:  350   |+1212 +1153 +1260 +1156 mAh
06/14/09 BC900 Discharge:  250   |+1243 +1176 +1264 +1172 mAh
06/14/09 BC900 Discharge:  100   |+1722 +1384 +2130 +3380 mAh
04/06/09 BC900 Charge:  700      |+1112  +994   n/a   n/a mAh 
02/26/09 C9000 Impedance Check:  | 1.73  1.79   n/a   n/a VDC
02/25/09 C9000 Break-In          |  932   888   n/a   n/a mAh#
02/20/09 C9000 Impedance Check:  | 1.79  1.89   n/a   n/a VDC
02/19/09 BC900 Refresh:  200/ 100| 1074   990   n/a   n/a mAh
02/07/09 BC900 Refresh:  700/ 350| 1130   952   n/a   n/a mAh
02/06/09 BC900 Charge: 1000      | +322  +241   n/a   n/a mAh
[Bought: 12/dd/00; Datecode: 05 00; ?? Storage ??; Icom; Thermometers]
[06/13/09-#3&4 found @ 0VDC in hand-fan w/switch ON!]
```


```
RadioShack 1300mAh AA NiMH       |   #5    #6    #7    #8
---------------------------------+---------------------------
07/03/09 C9000 Cycle3:   600/ 100| 1037   953   979   692 mAh
07/xx/09 C9000 Cycle2:   600/ 100| 1047  1008   987   747 mAh
07/xx/09 C9000 Cycle1:   600/ 100| 1053  1059   979   740 mAh
06/30/09 C9000 Impedance Check:  | 1.81  1.76  1.85  1.98 VDC
06/27/09 C9000 Discharge:  300   |  887   912   894   694 mAh
06/26/09 BC900 Refresh2: 500/ 250|  n/a   n/a  1070   967 mAh
06/25/09 BC900 Refresh1: 500/ 250| 1231  1205   984   769 mAh
06/24/09 BC900 Test:  500/ 250   | 1250  1263  1170  1102 mAh
06/23/09 BC900 Discharge:  250   |+1391 +1387 +1289 +1374 mAh
06/22/09 BC900 Discharge:  100   |+1716 +2150 +1385 +1135 mAh
06/21/09 BC900 Charge:  200      | +219  +149  +731 +2460 mAh
06/21/09 C9000 Impedance Check:  | 0.03  0.14  1.78  0.15 VDC
01/30/09 C9000 Break-In          | 1083  1082  1056  1006 mAh#
01/28/09 C9000 Discharge:  200   | 1014  1019  1012  1001 mAh
01/28/09 C9000 Charge: 1300      |  ---   ---   ---   --- mAh
01/28/09 C9000 Discharge:  200   |    0     0     0     0 mAh
[Bought: mm/dd/yy; Icom Transceiver]
--- Results not recorded
```


```
NiMh Rayovac       AA 1600ma  1: 05/11/09 -+1548mAh (Discharge BC-900  100) MTB
NiMh Rayovac       AA 1600ma  1: 05/09/09 -+1424mAh (Discharge BC-900  350) MTB
NiMh Rayovac       AA 1600ma  1: 05/02/09 - 1238mAh (Refresh2  BC-900  200) MTB
NiMh Rayovac       AA 1600ma  1: 05/02/09 - 1205mAh (Refresh1  BC-900  200) MTB
NiMh Rayovac       AA 1600ma  1: 05/01/09 - 1268mAh (Refresh1  BC-900  500) MTB
NiMh Rayovac       AA 1600ma  1: 04/30/09 - 1292mAh (Refresh1  BC-900  700) MTB
NiMh Rayovac       AA 1600ma  1: 04/10/09 # 1.68VDC (Impedance Check C9000) MTB#
NiMh Rayovac       AA 1600ma  1: 02/11/09 * 1174mAh ( BREAK-IN C-9000     ) MTB*
NiMh Rayovac       AA 1600ma  1: 02/09/09 - 1219mAh (Discharge C-9000  100) MTB
NiMh Rayovac       AA 1600ma  1: 02/08/09 -  185mAh (Charge    C-9000  800) MTB
NiMh Rayovac       AA 1600ma  1: 01/24/09 - 1365mAh (Refresh   BC-900  700) MTB

NiMh Rayovac       AA 1600ma  2: 05/11/09 -+1760mAh (Discharge BC-900  100) MTB
NiMh Rayovac       AA 1600ma  2: 05/09/09 -+1276mAh (Discharge BC-900  350) MTB
NiMh Rayovac       AA 1600ma  2: 05/06/09 - 1189mAh (Refresh5  BC-900  200) MTB
NiMh Rayovac       AA 1600ma  2: 05/05/09 - 1180mAh (Refresh4  BC-900  200) MTB
NiMh Rayovac       AA 1600ma  2: 05/04/09 - 1160mAh (Refresh3  BC-900  200) MTB
NiMh Rayovac       AA 1600ma  2: 05/04/09 - 1155mAh (Refresh2  BC-900  200) MTB
NiMh Rayovac       AA 1600ma  2: 05/03/09 - 1150mAh (Refresh1  BC-900  200) MTB
NiMh Rayovac       AA 1600ma  2: 05/02/09 - 1161mAh (Refresh2  BC-900  500) MTB
NiMh Rayovac       AA 1600ma  2: 05/01/09 - 1160mAh (Refresh1  BC-900  500) MTB
NiMh Rayovac       AA 1600ma  2: 04/30/09 - 1168mAh (Refresh2  BC-900  700) MTB
NiMh Rayovac       AA 1600ma  2: 04/30/09 - 1158mAh (Refresh1  BC-900  700) MTB
NiMh Rayovac       AA 1600ma  2: 04/10/09 # 1.84VDC (Impedance Check C9000) MTB#
NiMh Rayovac       AA 1600ma  2: 02/14/09 * 1125mAh ( BREAK-IN C-9000     ) MTB*
NiMh Rayovac       AA 1600ma  2: 02/12/09 - 1108mAh (Discharge C-9000  100) MTB
NiMh Rayovac       AA 1600ma  2: 02/11/09 -  149mAh (Charge    C-9000  800) MTB
NiMh Rayovac       AA 1600ma  2: 01/28/09 - 1288mAh (Refresh   BC-900  500) MTB
NiMh Rayovac       AA 1600ma  2: 01/24/09 - 1198mAh (Refresh   BC-900  700) MTB
```
I've begun moving my old, non-LSD cells REFRESH cycles from my 'old' La Crosse BC-900 to my 'new' Maha MH-C9000 due to the independent (i.e not tied to 2-to-1) and more varied (4 vs 19) Charge/Discharge rates. When 'Refreshing / Cycling Multiple Times', I discharge @ 100mA to attempt to discharge as much as possible but I charge at as high a rate as I can without generating excessive heat. When 'Charging / Cycling Once', I discharge @ 0.2C to have a standard reference to compare to (ala 'Break-In').

Also note that WARM is not HOT and both are relative. My older, non-LSD cells do get warmer than my new LSD cells but an old RadioShack Indoor/Outdoor Thermometer confirms they're not exceeding 120°F. (You can also unplug the BC-900 and get the thermistor readings during boot up.)


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## Mr Happy (Jun 30, 2009)

I have a hunch (unproven) that routinely charging cells at 200 mA on the BC 900 slowly but surely wrecks them. You won't notice it immediately, but after a few dozen cycles of such treatment the cells will have high internal resistance and reduced total capacity.


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## bob_ninja (Jun 30, 2009)

Mr Happy said:


> I have a hunch (unproven) that routinely charging cells at 200 mA on the BC 900 slowly but surely wrecks them. You won't notice it immediately, but after a few dozen cycles of such treatment the cells will have high internal resistance and reduced total capacity.



Besides older BC-900, also some younger Eneloop chargers use only 300mA rate. You can find a recent post with a link for a PDF chart for Sanyo/Eneloop chargers. I ended up with the slow one, 300 mA.

So why would Sanyo use such a slow rate then??!?!?!
I don't question validity of your suggestion. Just find it strange that Eneloop chargers would still use such a slow rate when most others are higher.

At some point here I read a rule that charge rate should match the discharge rate. For instance I use a set of cells in gizmos that draw about 300 mA so according to this rule slower 300 mA rate would be appropriate.


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## travelinman (Jun 30, 2009)

Taketheactive....I guess I'm not understanding what you mean by "missed termination". How could the BC900/700 not terminate when the LED indicator showed "full" or indicate the number of ma when using the "test" function?

I've been charging NiMH cells for over 2 years now on the BC charger and all indications including the anecdotal reports of longer run times, more transmission time (which is the real test as transmitting on a 5 watt handheld is heavy draw ~2A) on the same cells that are now 2 years old.

I'll do the tests you describe as soon as my roof is on, however my setup may alter the results.

I have a large finned aluminum heatsink (4" wide, X 1.5" deep X 7 or 8" long) that the charger rests on, with a 12v comp. power supply fan running at 1/2 speed on 6 or 7 volts blowing both above and below the charger. I also have an aluminum sheet bent to form an air deflector so that all the air goes directly toward the charger. There is NO overheating of any kind. As a matter of fact the cells are still cool to touch even when I have, on rare occasion charged at .5C.


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## Black Rose (Jul 1, 2009)

travelinman said:


> Taketheactive....I guess I'm not understanding what you mean by "missed termination". How could the BC900/700 not terminate when the LED indicator showed "full" or indicate the number of ma when using the "test" function?


The charger relies on the battery to tell it when it is full and is normally detected via -dV (minus delta V).

When charging at a low rate such as 200 mA, the battery is less likely to generate the -dV that tells the charger to stop charging.
In that case, the charger continues to put more energy into the cell until it is manually removed.

That is what is referred to as a missed termination.


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## TakeTheActive (Jul 1, 2009)

*Re: SLOW Charge Rate Is Not Always BEST Charge Rate!*



travelinman said:


> Taketheactive....*I guess I'm not understanding what you mean by "missed termination". How could the BC900/700 not terminate when the LED indicator showed "full" or indicate the number of ma when using the "test" function?*


I imagine many folks don't completely understand how their chargers operate. Per the specs (from both La Crosse and the CPF members) that I gathered in: *TTA's NiMH/NiCD Battery Charger Specifications Thread**:* *La Crosse BC-900*

the BC-900 has FOUR 'Shutoff Mechanisms' (aka Termination Methods): 
-DeltaV
Max Voltage
Max Temp
Max Time
If it misses one, there are three more 'Backups'.

Reviewing this example:

```
Sears DieHard 1300mAh AA NiMH    |   #1    #2    #3    #4
---------------------------------+---------------------------
06/16/09 BC900 Discharge:  350   |+1204 +1289 +1234 +1180 mAh
06/15/09 BC900 Test:  200/ 100   | 1100  1061  1165  1120 mAh
06/15/09 BC900 Discharge:  350   |+1212 +1153 +1260 +1156 mAh
06/14/09 BC900 Discharge:  250   |+1243 +1176 +1264 +1172 mAh
06/14/09 BC900 Discharge:  100   |+1722 +1384 +2130 +3380 mAh
```

note the OVERCHARGE of cells #3 and 4 during the 06/14 200/100mA DISCHARGE cycle. If I had done a 200/100mA REFRESH or TEST, I would have only seen results similar to the 06/15 200/100mA TEST cycle and been unaware of the damage being done. With 3380mA put back into a 1300mAh cell with an ACTUAL Discharge Capacity of 1120mAh, it appears that 'Shutdown Mechanism' #4 was the ONLY termination that worked. Make more sense now?

With the La Crosse chargers, it's important to understand WHICH capacity the charger is displaying.



travelinman said:


> ...*I have a large finned aluminum heatsink (4" wide, X 1.5" deep X 7 or 8" long) that the charger rests on, with a 12v comp. power supply fan running at 1/2 speed on 6 or 7 volts blowing both above and below the charger. I also have an aluminum sheet bent to form an air deflector so that all the air goes directly toward the charger. There is NO overheating of any kind. As a matter of fact the cells are still cool to touch even when I have, on rare occasion charged at .5C.*


This was discussed in the CPF Archives. Your setup is actually DEFEATING 'Shutdown Mechanism' #3 and possibly affecting #1 and #2 by cooling the expected normal heating of the cells as they approach full charge.



travelinman said:


> ...*I'll do the tests you describe as soon as my roof is on, however my setup may alter the results.*


Conducting the experiment on 'older', non-LSD cells WITHOUT the heatsink and fan stands a better chance of demonstrating the problem.



travelinman said:


> ...I've been charging NiMH cells for over 2 years now on the BC charger and all indications including the anecdotal reports of longer run times, more transmission time (which is the real test as transmitting on a 5 watt handheld is heavy draw ~2A) on the same cells that are now 2 years old.


If you've done the research and feel that your method is providing you with the maximum performance from your cells, stick with it. The bottom line, though, is that the maintenance of rechargeable batteries shouldn't be governed by a set of fixed rules but more by an understanding of the principles and then choosing what works best for your unique conditions. 

IMO, the further the user's requirements are from 'Daily Recharge after High Current Discharge', the less impact the variations in charging methods will have and the more impact time (i.e. cell aging) will have.


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## travelinman (Jul 1, 2009)

Tnx for the very informative reply. It's nice to have people like you willing to put a considerable amount of time into passing along info that everyone should have when considering "the care and feeding" of these LSD cells.

As they are fairly new technology, I'm keeping a close eye on which ones fail, and hopefully will now have a better understanding of why.

btw...I'm from the old school and keep my regular NiMH backups in the freezer.


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## kay188 (Jul 3, 2009)

So you guys are saying, It's bad to do refresh cycles on the eneloops, then put them into the fridge and leave them there?


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## bob_ninja (Jul 3, 2009)

kay188 said:


> So you guys are saying, It's bad to do refresh cycles on the eneloops, then put them into the fridge and leave them there?



Fridge is not applicable. LSDs are designed to hold charge for a long time at normal temps. Therefore there is no need for fridge, etc. You simply store them any place at normal temps, any place not exposed to direct sun light would be fine.


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## thedeske (Jul 3, 2009)

On my first break in with a new c9000 from TDis (0G0C01). 4 new AA Eneloops - I put in each battery and selected Break In and 2000MAH for capacity. About 15 seconds apart.

A little over an hour ago, the rest cycle started.
Slot 1 shows 2851 MAH / 1.44 V
2&3 are 2850/1.44&1.45
4 is 2851/1.44

The cells were barely warm about an hour before the rest cycle. Anything out of the ordinary here?

I didn't think about starting with a discharge last night, but I can on the next set if it's worth the trouble.


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## Black Rose (Jul 3, 2009)

Those figures are the amount of energy put into the cells (1.6x the entered cell capacity).

The numbers reported at the end of the discharge portion of the break-in cycle are the ones you are really interested in.


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## thedeske (Jul 3, 2009)

Black Rose said:


> Those figures are the amount of energy put into the cells (1.6x the entered cell capacity).
> 
> The numbers reported at the end of the discharge portion of the break-in cycle are the ones you are really interested in.



Ah - I'll get it eventually


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## thedeske (Jul 3, 2009)

Black Rose said:


> The numbers reported at the end of the discharge portion of the break-in cycle are the ones you are really interested in.



OK, I see. MAX figures.
2058
2049
2038
2034

Now I have an idea on time for these cells. Start of the last charge was 23hrs 40min or so.
If the last charge is actually 16 and I let it top for 2 hours, It's around 42 hours.


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## kay188 (Jul 4, 2009)

bob_ninja said:


> Fridge is not applicable. LSDs are designed to hold charge for a long time at normal temps. Therefore there is no need for fridge, etc. You simply store them any place at normal temps, any place not exposed to direct sun light would be fine.



I know fridge is not applicable, however, since it is a NiMH battery, storing it in the fridge helps lower it's discharge rate by 5% or something.

Most people cant be bothered to do so as the rate that the fridge helps it is too low.


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## clintb (Jul 5, 2009)

kay188 said:


> I know fridge is not applicable, however, since it is a NiMH battery, storing it in the fridge helps lower it's discharge rate by 5% or something.
> 
> Most people cant be bothered to do so as the rate that the fridge helps it is too low.


Somewhere, out in Internet land, is a R/C electric flier who did tests on the Eneloops when they first came to market. His review prompted some a response, and clarification of certain points, from Sanyo Europe. One of those was the slowdown of self-discharge by lowering the storage temperature. Basically, yes, the fridge is good for Eneloops, but it depends on how long you're going to store them and what the ambient temp would have been had you not stuck 'em in the fridge.


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## vali (Jul 6, 2009)

clintb said:


> Somewhere, out in Internet land, is a R/C electric flier who did tests on the Eneloops when they first came to market. His review prompted some a response, and clarification of certain points, from Sanyo Europe. One of those was the slowdown of self-discharge by lowering the storage temperature. Basically, yes, the fridge is good for Eneloops, but it depends on how long you're going to store them and what the ambient temp would have been had you not stuck 'em in the fridge.



I think you are talking about this -> http://www.stefanv.com/electronics/sanyo_eneloop.html


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## rlb4 (Jul 23, 2009)

So what would be the best way to charge and maintain Eneloops with the LaCrosse BC-9009? They are usually charged every several months.


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## nickanto (Jul 23, 2009)

Will my eneloops be ok in this charger for now?
http://data.energizer.com/PDFs/CHDC.pdf

I plan on ordering the eneloop charger when I get some more batteries, but will that do for now?


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## lebox97 (Jul 23, 2009)

here is one for you guy's - 
I have about 25 pcs AA Eneloop cells (a few too many apparently) - that were not getting used/cycled very often over the last year or two.

So after reading these posts - I put them all through a refresh/analyze and also a break-in on my MH-C9000 - and those that were not showing good capacity (below 1900) I ran a few more times through a refresh/analyze several times more, and if needed also a break-in or two...
all of these cells ended up at approx 1950-2000mah range

*EXCEPT for two cells!*
these two cells got better after 1-2 R/A then got worse each time thereafter - and are now down to low 1700maH
(These two have probably been R/A 8-10 times and B-I about 4 times)

Any ideas? 
run several more R/A, or B-I, or cycles, or save them for backup use?



NOTE: have about a dozen AAA's that refreshed to expected levels.


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## Anzycpethian (Apr 10, 2012)

I'm storing all my batteries in the *fridge *when not in use (Eneloops, Tenergy D Premiums for my TK70 and 18650s - all of them around 50% charged). Is there anything wrong with that habit? 
(I'm trying to cycle them regularly.)

I researched with Google and here in CPF posts but can't find a definite answer. PLEASE PLEASE HELP.


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## SilverFox (Apr 10, 2012)

Hello Anzycpethian,

50% charged is good for Li-Ion, and OK for NiMh cells. NiMh cells actually do a little better when they are discharged to 0.9 volts at a 1C discharge rate. Then you do a charge/discharge cycle frequently. If you want to keep them in top condition you run the cycle once a month. They will also do quite nicely if you stretch that out to once every three months.

Eneloop and other low self discharge cells are a little different. Most people charge them up and have them ready to go. Extended storage in a charged condition doesn't seem to effect their performance very much. Storing at 50% charge in cool temperatures may give you a little better results, but I don't think anyone has tested those conditions.

Tom


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## Samy (Apr 10, 2012)

I run them down in the device (flashlight,radio etc) as low as they can go, then charge them up fully and put them in storage rotation in a drawer. They seem to like being run right down then to receive a full charge. Half discharges or charges they dont seem to hold charge as long. In rotation they get used and charged about once or twice a month.

Cheers


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## tandem (Apr 11, 2012)

I find having teenagers who use X-Box remotes are very useful for cycling cells. The remotes drain the cells fairly completely. 

Unfortunately the expense of feeding the teenagers negates any cost savings to be had from going to Eneloop rechargeables.


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## HunkaBurninLove (Apr 12, 2012)

tandem said:


> Unfortunately the expense of feeding the teenagers negates any cost savings to be had from going to Eneloop rechargeables.



Good one, tandem :nana:


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## Anzycpethian (Apr 13, 2012)

I subscribed to this thread because it was very important to me and now just by chance I see that gmail treats the update-on-the-thread-mail as spam, argh...

Anyway, thank you for your answers!


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## WDG (Apr 13, 2012)

Anzycpethian said:


> ...I see that gmail treats the update-on-the-thread-mail as spam, argh...



<rant> In my experience, so-called "spam filters" are the *cure that is worse than the disease*. The part I hate most is when they refuse me the option of turning the damned things OFF. </rant>


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## TakeTheActive (Apr 22, 2012)

*Make Candlepower Forums a Contact...*



Anzycpethian said:


> I subscribed to this thread because it was very important to me and now just by chance *I see that gmail treats the update-on-the-thread-mail as spam*, argh...


Try adding the Candlepower 'Sender' address to your Contacts List / Address Book and see what happens.


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## bbb74 (Apr 22, 2012)

Anzycpethian said:


> I subscribed to this thread because it was very important to me and now just by chance I see that gmail treats the update-on-the-thread-mail as spam, argh...



That is easy to fix. In the spam folder, select the mails that aren't spam ... and hit the "Not spam" button. Gmail will stop treating them as spam.


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## MidnightDistortions (Dec 10, 2014)

Danne71 said:


> What is the point of buying lsd batteries if you cant store them? I thougt charging them every 3-4 month made them vital. Sanyo says it holds 85 procent after one year. They should have put a warning that storing a eneloop this long could harm the batteries. Is there any evidence that storing a eneloop for a couple of months is not good for them? I mean they havent been on the market long enough for this to be tested.





Yoda4561 said:


> It doesn't harm them, but you're only going to get 90% performance out of them instead of 100% after a couple years. It's fine if you just do the discharge-breakin every few years, they'll pick right back up. Some folks just like to keep things in top condition.





travelinman said:


> It sounds like people are collecting cells and have waay too many. Our use of NiMH cells shows exactly what has been discussed here. Have just enough that you can use them regularily. Any "extras" that you have, give them away to people that can use them regularily.
> 
> Like taketheactive says "use em or lose em".
> 
> ...





I thought i'd highlight a few posts in here. Over the past few days i have been refreshing a set of 2300mAh Energizer Power Plus LSD batteries and noticed 2 of them were showing 95% capacity (still refreshing) while the other 2 are showing 98%. Since the first set was currently being used in my EDC light and had to be initially charged i'm pretty sure i didn't leave them trickle charging for long. The other set was being recharged when they were already substantially full so i kinda wonder if i had overcharged the second set or if putting an additional charge after it was left sitting for about a month was actually better. Since those Energizers are nearly 2 years old (dated Jan 2 2013) they were not 'vibrant' but they did show a few discharges increased performance.

I only discharged near full when i bought them (August 19 2014) but never ran them through a discharge/charge cycle. At least i know Eneloops do not need to be cycled, but since they have plenty of cycles on the standard 2 amp batteries it doesn't hurt to do a break in cycle during initial purchasing. From testing my Energizers i am trying to determine whether 'topping' off the batteries after they have been sitting for about a month is better than recharging them from a 40-60% charge to cycle them. They do seem to handle themselves pretty well in storage and 98% isn't bad. I plan on doing another refresh on these batteries by July of 2015 to see whether they maintain the 98% or will increase or decrease by adding a trickle charge to them. Won't do more than a couple of hours of a top off charge, the 95% set was on trickle charging mode for 40 minutes while the 2nd set was only on trickle mode for about 10-15 minutes. All batteries were cycled at 250/500mA in the BC1000 La Crosse charger.

As for keeping extra cells, i'd say long as you cycle them every 2 or 3 years they should be fine to keep in storage. The entire point of having LSD rechargeables is to replace the alkaleaking batteries. I wonder if anyone has tried refreshing 5 year old Eneloops that have been sitting in storage to see their capacity and see how they hold up in long term storage.





Samy said:


> I run them down in the device (flashlight,radio etc) as low as they can go, then charge them up fully and put them in storage rotation in a drawer. They seem to like being run right down then to receive a full charge. Half discharges or charges they dont seem to hold charge as long. In rotation they get used and charged about once or twice a month.
> 
> Cheers



I haven't noticed too much of a difference, the voltage might be a bit lower. I did this every so often with my 2006 AAA Energizers that still hold 70% charge. Realizing though it might be more beneficial to run them all the way down in the La Crosse charger as they will only be run down to a safe level avoiding overdischarging the batteries. Other than that though running them half way hasn't bothered any of my LSD batteries just take them out after they finish charging . In fact taking them out when they reach 1.46 volts might not be a bad idea either. I use a rule of thumb of the more use the battery gets the more often you should fully discharge them but they don't require it every cycle.  I'd say for every 10 or 15 cycles, run them down fully.


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## WalkIntoTheLight (Dec 10, 2014)

MidnightDistortions said:


> I wonder if anyone has tried refreshing 5 year old Eneloops that have been sitting in storage to see their capacity and see how they hold up in long term storage.



Funny you mention that. I just cracked open a pack of Gen 1 Eneloops about 2 weeks ago. Their date stamp says they were manufactured in 2009, though I forget when I actually bought them. But dammit, I forgot to measure their voltage level to see what kind of charge they had on them. Anyway, I just charged them up and they work fine. I haven't checked to see if there's any decrease in capacity... maybe I'll check that out. I know my 2006 Eneloops still have close to their full capacity, although they're still used in stuff and so haven't sat idle for years.


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## MidnightDistortions (Dec 10, 2014)

WalkIntoTheLight said:


> Funny you mention that. I just cracked open a pack of Gen 1 Eneloops about 2 weeks ago. Their date stamp says they were manufactured in 2009, though I forget when I actually bought them. But dammit, I forgot to measure their voltage level to see what kind of charge they had on them. Anyway, I just charged them up and they work fine. I haven't checked to see if there's any decrease in capacity... maybe I'll check that out. I know my 2006 Eneloops still have close to their full capacity, although they're still used in stuff and so haven't sat idle for years.



Lol, darn! If only i refreshed my Energizer cells 2 weeks ago.. well at least after 5 years those 2009 Eneloops still work fine and you can still see what their max capacities are. Yeah usually NiMH cells are pretty vibrant when they are used, still these Energizers are proving to be good LSD cells. I'm keeping track of how many recharges the 2300mAh Energizer cells have but mostly because i couldn't find any info on the general cycle life they have. I should have left the only set of April 2014 Eneloops i got with the 16 pack in the package but i'm FIFO (first in, first out/using the oldest first) obsessive.


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## Phlogiston (Jan 7, 2015)

I found 4 new Sanyo MDU-01 USB travel chargers in a little shop in October, and bought the lot. Each charger came with two Gen1 AAA Eneloops (HR-4UTG) with a manufacturing date of September 2006. They've presumably been sitting undisturbed in that shop since they were made. 

They all had a voltage of about 1.28V and roughly 2/3rds of their charge. When I did a test cycle on them with my BL-700 charger, every cell showed at least 770mAh of capacity. Six of them have been delivering that capacity in my lights while I was doing runtime tests last week. 

I'm impressed. Eneloops really are quality cells.


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