New Imedion batts

[Doug.S]

I just bought 8, MAHA IMEDION AA 2100 MAH ULTRA LOW DISCHARGE batts.

What is best way to use them for first time?

Use when needed or run a break-in cycle (or two?) on C9000 first

I will do a ZTS check first and could run a discharge cycle to test capacity.

I don't really need to use them until next week.

Any advice?

 

[bob_ninja]

No break in or charging needed. Just use them as they should have about 70% SOC.

 

[Anders]

Hello Doug.S.

If you decision is to do a break-in cycle ,don't forget to discharge them first.

I don't think its neccesary, just do as bob_ninja suggested.


Anders

 

[Doug.S]

Thanks...here are my test results using ZTS checker...
tested "as received" (did nothing with/to them)
6 = 100%
1 = 80%
1 = 40%

I'll discharge the 2 low ones (80% and 40%) then break-in cycle and hope they are both good batts....80% probably fine but 40% concerns me.

 

[hopkins]

You could mark the 40% battery with a sharpie and keep an eye on
it performance.
If it continues to have higher than normal discharge... lets see 1 out of 8
is a 12% failure for this Mfg...
Not sure if that number is to be expected or something to get mad about..?

 

[BabyDoc]

I just bought 8, MAHA IMEDION AA 2100 MAH ULTRA LOW DISCHARGE batts.

What is best way to use them for first time?

Use when needed or run a break-in cycle (or two?) on C9000 first

I will do a ZTS check first and could run a discharge cycle to test capacity.

I don't really need to use them until next week.

Any advice?

I called customer service at Maha and asked if they recommended a break-in for the Imedions, should you own a C9000 charger. I was told that while you could use them without break-in, they did recommend break-in for the best possible performance. Furthermore, no discharge is necessary, nor even preferable, before doing the break-in. The service representative explained that you can't damage even a fully charged battery in 16 hours, by breaking it in at 0.1C.

Is this hard to believe that you need not discharge these batteries before break-in? It was for me. I called Maha a second time and spoke to a different service rep and got the same answer. So unless Maha wants us to fry batteries and then buy more, I would guess their advice should be trusted. If we can't trust their advice about their own products, then who is the final word?

 

[Bones]

I called customer service at Maha and asked if they recommended a break-in for the Imedions, should you own a C9000 charger. I was told that while you could use them without break-in, they did recommend break-in for the best possible performance. Furthermore, no discharge is necessary, nor even preferable, before doing the break-in. The service representative explained that you can't damage even a fully charged battery in 16 hours, by breaking it in at 0.1C.

Is this hard to believe that you need not discharge these batteries before break-in? It was for me. I called Maha a second time and spoke to a different service rep and got the same answer. So unless Maha wants us to fry batteries and then buy more, I would guess their advice should be trusted. If we can't trust their advice about their own products, then who is the final word?

It occurs to me that we can just let our common sense be our guide.

Regardless of whether or not a fully charged cell can be damaged by a .1C rate of charge for 16 hours, we only have to keep in mind the reasons we are subjecting our cells to the forming or break-in charges in the first place.

As I understand it, one is to break up large chrystals to reduce the cells internal resistance and prevent separator perforation; another is to better integrate the elecotrolytes, which also helps to prevent the formation of hot spots, especially under high discharge rates.

Combined, these processes generally act to increase our cells capacity, performance and longevity.

Since the most essential part of the process appears to be the slow, deep discharge, why wouldn't we get a head start by doing one at the outset, especially when it will allow the first charge at .1C to better do it's thing as well?

Regardless of MahaEnergy's statements to the contrary, they are never going to convince me that pumping 3360mAh into a fully charge cell isn't having a detrimental effect.

I am also sure they will never advise us of the converse, being that it's actually benefiting our cells; something we do know conducting a deep discharge most assuredly does.

MahaEnergy's technical support just slipped a little in my esteem.

 

[Mr Happy]

Since the most essential part of the process appears to be the slow, deep discharge

Just in terms of weighing up all the evidence, where do we find the information about deep discharge being the most important part of the process?

I have seen this point advanced for NiCd chemistry, but I am less sure about NiMH.

When a gentle overcharge occurs, it activates shuttle reactions in which there is a continuous cycle of chemical species migrating back and forth from one electrode to the other. It could be that this continuous cycle of the shuttle reactions during the long slow charge is what is most important to form and distribute the cell contents...?

Personally I don't know exactly what part of the process is most beneficial to the cell, so I am not immediately willing to doubt what Maha say about it.

 

[Bones]

Just in terms of weighing up all the evidence, where do we find the information about deep discharge being the most important part of the process?

I have seen this point advanced for NiCd chemistry, but I am less sure about NiMH.

When a gentle overcharge occurs, it activates shuttle reactions in which a continuous cycle occurs of chemical species migrating back and forth from one electrode to the other. It could be that this continuous cycle of the shuttle reactions during the long slow charge is what is most important to form and distribute the cell contents...?

Personally I don't know exactly what part of the process is most beneficial to the cell, so I am not immediately willing to doubt what Maha say about it.

In that case, wouldn't common sense indicate that the most beneficial forming charge would be 32 rather than 16 hours at .1C?

Insofar as which process is more beneficial, can we not project the consequence of removing one or the other?

In other words, which would produce the better performing cell, one that is charged at .5C with regular deep discharges, or one that is charged at .1C with no deep discharges?

I would put my money on the former...

 

[BabyDoc]

In that case, wouldn't common sense indicate that the most beneficial forming charge would be 32 rather than 16 hours at .1C?

Insofar as which process is more beneficial, can we not project the consequence of removing one or the other?

In other words, which would produce the better performing cell, one that is charged at .5C with regular deep discharges, or one that is charged at .1C with no deep discharges?

I would put my money on the former...

In fact, using a Maha C9000 charger, the break-in cycle (16 hour Charge/REST/Discharge/REST/16 hour Charge) does give you a total of 32 hours of charging at 0.1 C. Notice there is only 1 Discharge period while there are two Charge periods. It appears Maha believes that the two low current, 16 hour charge cycles are more important for forming a cell, than is the single discharge cycle. If they had believed otherwise, wouldn't they have programmed the C9000 to auomatically discharge every cell, and then charge it for 16 hours at 0.1C a single time? Certainly, they had the ability to do so, if it had been preferable, or if they thought charging an already fully or partially charged cell with a low 0.1C current for 16 hours would be in any way detrimental.

Finally, if charging cells regularly at 0.5 cc with regular deep discharges was all you needed to keep a NiMH cell performing well, why would MahaEnergy recommend in the instructions for the C9000 that you do a break-in again after every 30 charge/discharge cyles? Apparently, some chemical magic happens during break-in that rejuvenates a cell in a way that corrects for performance losses that occurs with repeated simple charge/discharge cycles.

 

[Bones]

In fact, using a Maha C9000 charger, the break-in cycle (16 hour Charge/REST/Discharge/REST/16 hour Charge) does give you a total of 32 hours of charging at 0.1 C.

If charging cells regularly at 0.5 cc with regular deep discharges was all you needed to keep a NiMH cell performing well, why would MahaEnergy recommend in the instructions for the C9000 that you break-in again a cell after every 30 charge/discharge cyles? Apparently, some chemical magic happens during break-in that rejuvenates a cell in a way that doesn't happen with repeated simple charge/discharge cycles.

Granted BabyDoc, but it was not my intention to allege that a .5C charge with regular deep discharges was as beneficial as a break-in cyle, it was to support my statement that it would keep a cell healthier than a constant diet of .1C charges.

In fact, according to SilverFox, slow charging may actually promote large chrystal and dendrite growth, which is one of the reasons why he recommends charging at .5C to 1C.

I readily admit that I was splitting hairs when I stated that the most beneficial part of the break-in process was the .2C discharge, but I still think the hair splits finer in my favor...

As well, according to William Chueh, the lead engineer on the MH-C9000, a break-in cycle actually consists of a .1C charge followed by a .2C discharge, with the last charge purposed to ready the cell for use.

This is from the Thomas-Distributing Website MH-C9000 FAQs:

Question:

Does the MH-C9000 have a Charge/Test that follows the proper IEC standard procedure (rest period of one hour, IEC standard)?

Answered by William Chueh of Maha Energy:

The MH-C9000 does have a built-in "IEC" capacity program under the "Break-In" mode.

The sequence is:

1. Charge for 16 hours at 0.1C (user inputs capacity - though for safety reasons, temperature monitoring will be enabled, but no voltage termination).

2. Rest 1 hour.

3. Discharge at 0.2C (up to 1.0A).

4. Rest 1 hour.

5. Repeat step 1 to 4 for four times.

6. Last discharge capacity is saved.

7. Charge - battery ready for use.

Anyway, returning to the original query respecting whether MahaEnergy was correct in advising against discharging a cell before a break-in cycle, I still maintain it's better to first do a discharge for the reasons already stated...

 

[Mr Happy]

I still maintain it's better to first do a discharge for the reasons already stated...

I always do a discharge myself, but maybe that's because I'm paranoid?

Apart from taking more time, it can't hurt, can it? Doing a discharge to begin with is just cycling the cell a little more than not doing so.

Now, there is an interesting thing that I can say here as an engineer, having learned it a few times over the years: there are often times that our intuition tells us something and we really want to believe it, but when the actual hard tests are performed our intuition turns out to be wrong. So while I always discharge cells before running a break-in cycle, it may be that my intuition about this is wrong. Since I don't know and don't have a way to find out, I shall continue doing what I do in blissful ignorance.

 

[Bones]

So while I always discharge cells before running a break-in cycle, it may be that my intuition about this is wrong. Since I don't know and don't have a way to find out, I shall continue doing what I do in blissful ignorance.

As shall I, only in much deeper blissful ignorance ...

 

[BabyDoc]

This is from the Thomas-Distributing Website MH-C9000 FAQs:
Question:

Does the MH-C9000 have a Charge/Test that follows the proper IEC standard procedure (rest period of one hour, IEC standard)?

Answered by William Chueh of Maha Energy:

The MH-C9000 does have a built-in "IEC" capacity program under the "Break-In" mode.

The sequence is:

1. Charge for 16 hours at 0.1C (user inputs capacity - though for safety reasons, temperature monitoring will be enabled, but no voltage termination).

2. Rest 1 hour.

3. Discharge at 0.2C (up to 1.0A).

4. Rest 1 hour.

5. Repeat step 1 to 4 for four times.

6. Last discharge capacity is saved.

7. Charge - battery ready for use.

Anyway, returning to the original query respecting whether MahaEnergy was correct in advising against discharging a cell before a break-in cycle, I still maintain it's better to first do a discharge for the reasons already stated...

It is rather interesting that according to this answer from the engineer at Maha, he would recommend repeating a break-in cycle up to 4 times on a new battery. If all this dendrite formation and large crystal formation caused by repeated slow charging was detrimental, why would he recommend doing it up to 4 times? I still wonder whether Maha just want to sell you new batteries more often.

Personally, I don't see any harm in discharging a new, not fully formed battery, before you actually break it in. Even an experiment of doing a break in with and without initially discharging a battery, would prove little. I can't imagine much of a difference in the capacity measured either way. To determine whether it had a beneficial or detrimental effect on the battery's life, multiple charge/discharge cycles would be needed in an even more difficult experiment. Like the rest of you, I am skeptical of the answer given by Maha and will carry on in my blissful ignorance doing what seems right - discharging first. In any case, these batteries aren't all that expensive. We only obsess over these questions because it is fun to do so.

 

[Doug.S]

More follow-up on these batt.s

For the two "low charge at receiving", I discharged, then break-in...both discharged about what you'd expect at 40% and 80% charge.

After break-in one was 2149 and other was 2153; about right for a new 2100 batt.

Having finished these 2 of eight I ZTS rechecked the others that were at 100% a few days ago....sorry to learn 1 was now 60% and 2 were 80% (no load, just sitting at room temp in a case)....OK so 100% to 80% could be OK as the ZTS scale is course, but 100% to 60% seems like a not so slow discharge rate.

so I'm doing a break-in now on these 3 and when done will check the remaining 3 still at 100% today... I need them all balanced at full charge anyway.

I did not mark them, I don't plan a long term study...I'm really only a casual user mostly for SLR camera supplemental flash (4 AA's at a time for the flash unit).

 

[radellaf]

For the most part, I think we're splitting hairs over what 16h overcharge is going to do. They can take it, I have zero evidence to think it could possibly help, though. And some that overcharge is bad even at low levels. Just, not enough that I'd expect Maha to recommend one way or another, really.

Also, I have not been able to find anything written about the electrolyte thing outside of CPF, and I have looked.

Electrolyte dispersion just happens as a part of normal use. What surprised me (i forget the source), is eventually it can migrate so much into the plates, that the separator is too dry.

Brand new, the separator has the most electrolyte that it will have, and if it is too saturated, then gas exchange between plates will be slower. i.e. -- overcharge sounds to be worst for new cells. OTOH, again, that little, that slow... I wouldn't argue with Maha that it doesn't make any difference.

-----

#1 reason for break in, and it's a good one, is that long-stored cells can fail to -dV charge terminate properly, and overcharge at high rates is unquestionably harmful.

 

[Bones]

We only obsess over these questions because it is fun to do so.

+1

 

[Bones]

More follow-up on these batt.s

Snip...

Just wanted to extend my appreciation for the information on the Imedions Doug.S.

Posts like yours are a big part of what makes participation in this formum fruitful as well as fun.

 

[aim54x]

I just got my C9000 and some new imedions...my eneloops have never been "broken in" but I have decided to discharge and break in my imedions.

This thread helped heaps