Questions about using MH-C9000 charger

Hello,

I am new to this forum and I just got a MH-C9000 charger when it is on sale on Newegg canada. I have a few questions on using the charger and hope some one can help me answer it.

1. I have several rechargeable Ni-MH AA batteries just show "HIGH" or simply show nothing and repeat to the selection screen as if I insert a new battery again and again. Some of them are old batteries which I assume are dead. But there is one Sanyo 2500mah which is not too old (2 years old I guess) and showing "HIGH" and when I discarge, it shows 0 mah, however, I can still use it in my wireless mouse just fine. Can I do anything in general to let the charger accept batteries like that?

2. I just start to use break-in mode after "refresh and analyze" most of my batteries, strange enough, first battery went from 810mah to 770mah after break in (OK, not too much difference), second Sanyo 2500mah went from 1850mah (evaluated after using refresh and analyze mode) to 6 mah after break-in?? Does that mean sth. is wrong, can break-in mode be harmful for some batter?

3. I bought several new pack of AA duraloops and one pack of new powerex 2700mah AAs, I have no use of them probably until a few month later. Is that better to break-in these batteries now, or should I wait till I have use for it to do a break-in.

4, How is the lifespan of enloops and other rechargebles if I did not use them that much. I bought more batteries than I need when they are on sale. Just wondering how long they will last if I didn't use them much.

Thanks,

1) I had Powerex 2700's do that within a couple years. You can fiddle with them, but I never had any luck rehabilitating these cells. I still have a few left that work in low-draw items, but really nothing much else. I mostly use a C.Crane or a dumb charger for them. When the C.Crane rejects them, they go in the recycling bin.

2) This is really two separate questions.
First, don't give too much weight to the numbers you get from R&A. I consider R&A more for keeping a general eye on the health of the cells. The Break-in numbers are more accurate.
Second, your cells that read very low capacity from the Break-in have a high enough internal resistance that they cause the discharge portion of it to end prematurely. Again, my experience is that they're not likely to get any better.

3) Someone else will likely have a better answer for this one, but I'd probably tend to leave these alone. Maybe refrigerate them.

4) Eneloops seem to tolerate this quite well. Powerex 2700's, not so much.

riveting said:

Hello...

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riveting said:

...I have a few questions on using the charger and hope some one can help me answer it...

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riveting said:

...Thanks

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Hello riveting.

Welcome to CPF.

1. throw the HIGH cells away. The charger measure the cells to see if it is risky to charge them, cells with high IR is obsolete.

2. Strange, it looks like the cells are old.

3.It depends, what status is the Voltage of the cells?. If the cells is around 1,2 Volts or higher, do nothing.
If the cells have a lower voltage, do a break in, discharge them and charge them @ 1A =15-20 minutes. If you dont know, do the latest suggestion and buy a DMM.

4.There is quite a greate difference between LSD cells and common old ones, read on the forum about LSD cells and you dont buy anybody else.
You have to charge and discharge the old regular NIMh cells but not LSD cells.

Anders

Got the Newegg daily deal, eh? 50 bucks a pop was awesome! I got in on it too ... and this charger makes my LaCrosse unit look like a mini-charger!

bill_n_opus said:

Got the Newegg daily deal, eh? 50 bucks a pop was awesome! I got in on it too ... and this charger makes my LaCrosse unit look like a mini-charger!

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Ditto

BTW,. I have had two batteries (both new, one an eneloop and one a non-name, both AAA) go HIGH on me while in break-in. Interestingly enough both were in the same slot (#1), so I wonder if that has anything to do with it. I plan to try to charge them again in another slot. The manual actually does state that if HIGH is reported but you "question" the report, to just retry charging them.

Sparkss said:

Ditto

BTW,. I have had two batteries (both new, one an eneloop and one a non-name, both AAA) go HIGH on me while in break-in. Interestingly enough both were in the same slot (#1), so I wonder if that has anything to do with it. I plan to try to charge them again in another slot. The manual actually does state that if HIGH is reported but you "question" the report, to just retry charging them.

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I believe the manual says to try "discharging" them (I don't actually have the manual here at the moment). At least that's what I did to one of mine that was reported as high, and after discharging, I was able to charge it. Mind you, the cell is shot anyway... it only holds about 1600mA and it's a 2100mA Sanyo. Still... it's part of a set of 4 that I use on the bench for testing lights..... they work, just don't keep a charge for as long as I would like.

Regards

Christian

Thanks for all the replies. Yes, I got this during the newegg Shellshocker sale, awesome price. I am trying to break-in all my batteries and it is working 24/7 now, it seems that I should probably get two during that sale as break-in process is really long.

I trowed away some really old batteries, and I'll try to discharge my sanyo 2500mah to see if the charger will accept it afterwards.

TTA, the pick you provided is really helpful. I only read some of them, will try to read more when I have some time.

If you look carefully on the display when the charger starts a charge you will notice a volt number, if this first number is up over 2.05 volt or so you will have HIGH soon on this particular cell.

New cell with low IR measure about 1,50 volt.

Anders

A really good resource for interpreting the MH-C9000's impedance check is Interpreting Maha MH-C9000 Impedance Check Voltage linked from TakeTheActive's TTA's Picks for Best Answers to Rechargeable Battery Questions. This certainly helped me better understand the condition of my cells, and is one of the things I watch when I insert a cell.