When to Replace AA Eneloops?

gnnbtrn wrote in post #18784364
I still do not understand how to sort bad from good batteries. Some of mine are definitely bad, but I cannot find with one

I don't understand your La Cross charger. Maybe it can do battery testing and rejuvenation, and if so, follow its instructions.

Here's what I do to find bad batteries.

Typically I use a set of 4 in a flash. When the recycle gets slow the set is deemed discharged and I take them out. Then I use a simple battery tester (which presumably loads the batteries during the test) to check each battery. Often just one of the four is a dud. So just toss that one. If the whole set tests about the same, and if the life seems inadequate, then they are all bad.

My battery tester looks kind of like this:
https://www.dhgate.com …utton-cell/406972293.html

gnnbtrn wrote in post #18784360
I have set 4 batteries on Test mode, and 15 hrs later they are not done.
I know the refresh will take a log time, but I thought the Test will be a bit faster.
Is it normal?

I am not quite sure how the new LaCross charger work. With my old version you can determine the charge current. I typically choose 1500 mA for charging and 500 mA for discharge (recommended charging current is between 0.5 C and 1 C , e.g. for 2000 mA this translates into 1000 to 2000 mAh). This means that a full cycle takes about 6-7 hours (top of charge, discharge and charge again). If you don't change the standard values then things can take 2 - 3 times longer (in my case 500 mA for charging and 200 mA for discharge which adds up to about 14 - 16 hours for a full first cycle). You should get a capacity reading in mAh after the first full discharge.

The Candle Power forums would likely have a thread on this.

I use the MAHA C9000 and the charger makes it simple to determine what cells are working well. The charger will reject the battery or when done cycling what the cell charged up to. This way I can group similar capacity batteries together. I have a couple AAA that the capacity is at 200mAh and the run times reflect the dropping performance of the cell.

Worthwhile to have a charger like this. Some older cells have responded well to a break-in or refresh analyze cycle.

https://www.mahaenergy​.com/mh-c9000

gnnbtrn wrote in post #18784360
I have set 4 batteries on Test mode, and 15 hrs later they are not done.
I know the refresh will take a log time, but I thought the Test will be a bit faster.
Is it normal?

What model charger are you using? Some La Cross models have user adjustable charge rates and can be slow if set on lowest setting. As an example, the BC700 has charge rates of 200,, 500 and 700 mA.

John from PA wrote in post #18784412
What model charger are you using? Some La Cross models have user adjustable charge rates and can be slow if set on lowest setting. As an example, the BC700 has charge rates of 200,, 500 and 700 mA.

I have BC-900.
For some reason I cannot find the model on LaCrosse website.
I can select current on CHARGE mode, but cannot select current on TEST mode

gnnbtrn wrote in post #18784525
I have BC-900.
For some reason I cannot find the model on LaCrosse website.
I can select current on CHARGE mode, but cannot select current on TEST mode

Just had a thought. Possibly an issue with the charger and not batteries? Maybe get a maha C-9000 powerex?? Yah I know. Really reaching.

gnnbtrn wrote in post #18784360
I have set 4 batteries on Test mode, and 15 hrs later they are not done.
I know the refresh will take a long time, but I thought the Test will be a bit faster.
Is it normal?

I have two BC-700s. Yes, this is normal; particularly if you're using a lower voltage. Test, iirc, does a single charge/discharge cycle before charging again to test the capacity. So, this is going to take about 2-3x longer than a typical charge if you started with an "empty" battery in good health.

gnnbtrn wrote in post #18784525
I have BC-900.
For some reason I cannot find the model on LaCrosse website.
I can select current on CHARGE mode, but cannot select current on TEST mode

The manual can be found (and downloaded) at https://www.manualslib​.com …nology-Bc-900.html#manual. Page 4, at
https://www.manualslib​.com …Bc-900.html?page=4#manual seems to address the "Test" mode and setting of the charging current.

I do note that for "Test" mode the batteries will be first fully charged, then discharged, then charged again so it does not surprise me that this is taking you an unusual amount of time, especially if the default charge level of 200 ma is being used, and it seems it will be unless you do something to select something different.

This may be of interest among AA cells:
https://www.youtube.co​m/watch?v=0A1GvQ40j0Q

Thanks everyone for replies!
I think I have found the problem.

The problem was that I did not use my Eneloops for a long time. I stopped actively shooting about two years ago. Though I have always kept my camera and flashes handy,
I was taking much less pictures then before, especially with the flash light. (I have moved to new place and had to spend my time on remodeling more than anything else)

Now, I have figured out how to do TEST mode on BC-700 and change current to 700. It did speed up the process a lot.
I have run TEST on all of my batteries and measured voltage right off the charger.
Some of them were 1.3xx, some 1.2xx and some 1.1xx
I ran those with lowest voltage through the TEST again and they are coming back to 1.2xx or 1.3xx

Then I measured voltage again after one day.
So far I have found two that has voltage gone from 1.2xx to 0.9xx within 24 hours. These ones I am running through REFRESH mode, but if I cannot revive them, I will just recycle them

Some of the batteries I using now do not hold as long as they used to, but at least I can use them for some short time. I think if I will recharge/discharge them more often - they might be back.
But if it is not, it is not a big deal.

Currently I have 2 flashes and 2 remotes that use 12 batteries a once. I have 24 batteries.
I will run for a week or so, but if I am not happy - I will just recycle half worst batteries and buy Amason Basic x12 - just to have my AAs in two different color for easier detection old/new batteries.

Thanks again, everyone. I could not resolve it without you.

You can use one of These to analyze and condition the batteries. They are especially useful in conditioning new batteries which enables you to match similar powered batteries.