Maha MH-C9000 SUPPORT / FAQ - continuation

[Mr Happy]

I was under the impression that break in cycles are good for the cells and the more run on them the better.

Well no, not exactly. Like all things, break-in cycles are good in moderation. If you do too many of them you will wear out your cells.

A tip when doing more than one break-in cycle, is don't run them back-to-back. Since a complete cycle is charge-discharge-charge, you should run a discharge at 0.2C after the first cycle. If that shows an improvement, run another break-in, otherwise don't.

So your sequence would be break-in; discharge; break-in; discharge etc.

I can live with out them and get some new 2700's

Dude, what are you thinking of?! If you have cells that sit idle and want to replace them, get LSD cells like Eneloops. 2700's are possibly the worst cells you could buy unless you re-charge and use them daily.

[pobox1475]

If you have cells that sit idle and want to replace them, get LSD cells like Eneloops. 2700's are possibly the worst cells you could buy unless you re-charge and use them daily.

I was thinking of 4 or 8 2700's for use when I could use extra power (night fishing) and neglected to mention that I have a dozen AA & AAA Eneloops on hand and discharge each cell before a break in. The break in's generally were run a few days apart. Not actually "back to back to back". I have read in a thread here that two or three break in's are a good idea for a brand new or older cell that needs rejuvenation. I assumed that three would be more than sufficient and would do no harm. I also read that a break in or two is good for new Eneloops. Is this true?

[Mr Happy]

What I was suggesting about the break-in cycles is that the cell will be charged at the end of the cycle. So for efficiency when doing more than one break-in, you could do it like this:

BREAK-IN                  DISCH       BREAK-IN
charge-discharge-charge | discharge | charge-discharge-charge | etc...

If the second discharge gives a higher capacity than the first (break-in) discharge, then continue. Otherwise don't do any more break-in cycles.

The timed conditioning charge does put some wear on the cell. For this reason a conditioning charge is only advised every 25 charges or so rather than every time.

If you know and understand the advantages and disadvantages of LSD cells vs. 2700's then never mind what I said. But do bear in mind the early failure and high self-discharge that so many people have reported of 2700 cells. You may be better off carrying a spare set of Eneloops in the long run.

It's possible that a break-in or two is beneficial for new Eneloops. The truth is that opinions vary and it's hard to say with certainty either way. I have tested Eneloops before and after break-in cycles, and honestly I find it hard to see any difference in performance.

[pobox1475]

BREAK-IN DISCH BREAK-IN
charge-discharge-charge | discharge | charge-discharge-charge | etc...

This is the procedure I have been using.

If the second discharge gives a higher capacity than the first (break-in) discharge, then continue. Otherwise don't do any more break-in cycles.

I should have took note of the readings after the first runs. Now my only option to gauge any improvement (or opposite) is to run a third.

But do bear in mind the early failure and high self-discharge that so many people have reported of 2700 cells. You may be better off carrying a spare set of Eneloops in the long run.

Figured they would have fairly high self discharge but did not know about failures. I guess that additional 700 mAh on paper had my attention. I will take your advice and utilize the Eneloops.

It's possible that a break-in or two is beneficial for new Eneloops. The truth is that opinions vary and it's hard to say with certainty either way

I plan to run a couple just to ensure I don't have a rare dud. If anyone has strong reason to believe running break in's on Eneloops is a mistake, please chime in.

[Mike_FR]

Hi,

I recently ordered a MAHA C9000 at Kaidomain and infortunately it has a defective slot#2 just after unpacking.
After a look at the product case, I found a cross at the second slot

Does anybody has already had such bad experience with kaidomain ?

Does anybody has already had a defective slot on a C9000 ?

The slot#2 is not able to charge and switch to trickle charge after settings (Done is not set near the slot number when it does that).


Thanks for your advice.

[pobox1475]

I recently ordered a MAHA C9000 and infortunately it has a defective slot#2

Your charger has a three year warranty, so if dealer is no help then I'm sure MAHA will take care of you.

Done is not set near the slot number when it does that

Not sure exactly what you mean. What ever option you choose for slot #2 nothing happens? Is it applying current to the cell? Will it give you the voltage? I assume you are stating than after you use #2 it never finishes with the "Done" indicator. Have you tried various cells in that slot?

[Mike_FR]

Yes, but sending it back and forth will cost more than the product itself.

Charging is not working in any case (charge mode, break-in, refresh/analyse). After inserting the battery and selecting the current value, it starts, but immediately switch to a low current value (some milliamps). The voltage seems correct. I've tried lot of cells and all of them worked fine on the others slots.

[pobox1475]

Yes, but sending it back and forth will cost more than the product itself.

I would call MAHA. I'm sure they would be interested in getting their hands on your unit to trouble shoot the issue. They may even cover your shipping cost. I have heard that their C.S. is outstanding .

[Mike_FR]

I'm located in France (European country).
Don't know if the Maha C.S. is covered in this area. There are no Maha resellers in my country.

[Anders]

Hello Mike_FR, Welcome to CPF

Maybe you can contact Maha in UK if you don't find any resellers in France
http://www.mahaenergy.co.uk/

I bought my C-9000 from US, I contacted Mahaenergy here in sweden when it became defective, they changed it immediately.

There was no mahaenergy in sweden at the time C-9000 was introduced.

This one is working like a charm.

Anders

[TorchBoy]

I have heard that their C.S. is outstanding .

That was probably from me. It is.

There was no mahaenergy in sweden at the time C-9000 was introduced.

Similarly here, but it was no problem (apart from the delay and slight hassle). I suspect I may have had the first two in New Zealand, after they replaced my malfunctioning first unit.

[Niconical]

Hello.

I’m new to this thread, but I just got a Maha C9000 charger, and I have a few questions please.

In case it is relevant, the serial code on the back of the charger is 0H0BB.

In no particular order....

1. The manual recommends charging “not below 0.3C and not above 1.0C”.

My eneloop AA (previously tested on a La Crosse BC700) are all 2100 or so mah.
So, putting it halfway between the recommended levels I will charge them at 1500mah, and the AAA at around 600mah, both around 0.7C.

Is that a good idea or is it best to be higher/lower?

2. When I insert a AA, it sits level. When I insert a AAA, it first sits at an angle, with the positive higher than the negative. The charger detects it fine, but it looks like if I push a lot harder it will slot down to level. Is it supposed to be at that angle, or should I push down hard so it is level?

3. What is the difference between top-off charging current (100mah) and maintenance charging current (10mah) ?

Thank you

[Black Rose]

I normally charge my cells at 0.5C of their labelled capacity.
In this case Eneloop AA at 1000 mA and my AAA at 400 mA.

When I insert AAA cells (any brand) into the C9000, I roll them a bit to get them to seat better in the charger.

[Bones]

...
1. The manual recommends charging “not below 0.3C and not above 1.0C”.
...

Item 13 of the Eneloop Facts & FAQs recommends against charging at rates that will complete a charge in under two hours.

Accordingly, the maximum rate recommended for the Eneloop AA and AAA cells are, respectively, 1000mAh and 400mAh.

You will have noted that the default charge rate for the MH-C9000 is also 1000mAh, which makes charging the Eneloop AA cell an insert n' go proposition.

Incidentally, the charge rate should be based on the capacity stated on the cell and not its consumer measured capacity.

...
2. When I insert a AA, it sits level. When I insert a AAA, it first sits at an angle, with the positive higher than the negative. The charger detects it fine, but it looks like if I push a lot harder it will slot down to level. Is it supposed to be at that angle, or should I push down hard so it is level?
...

Unless they've changed the basic design of the MH-C9000, the AAA cell should sit parallel with it's charging bay, so they may not be properly seated. Rather than push it straight down though, try seating the cell in the bottom contact and then pushing the cell firmly towards the bottom contact while lowering it into the the opening for the top contact.

The idea is to slip rather than snap them into place, which is less stressful on the cells and charger.

...
3. What is the difference between top-off charging current (100mah) and maintenance charging current (10mah) ?
...

The terms are more or less self-explanatory.

The top-off charge is applied at the end of the primary charge cycle, and is intended to 'top' off the amount of charge in the cell at a rate that will miniumize the amount of current that is converted to heat.

The maintenance charge follows the top off charge. It is intended to offset the self-discharge that NiMH cells experience.

Since the Eneloop are low self-discharge cells, they don't benefit from a maintenance charge as much as other NiMH cells.

Regardless, it is generally believed that prolonged maintenence charging may be more harmful than beneficial to all NiMH cells.

[Mr Happy]

1. The manual recommends charging “not below 0.3C and not above 1.0C”.

My eneloop AA (previously tested on a La Crosse BC700) are all 2100 or so mah.
So, putting it halfway between the recommended levels I will charge them at 1500mah, and the AAA at around 600mah, both around 0.7C.

Is that a good idea or is it best to be higher/lower?

You can charge AA Eneloops at any rate up to 2000 mA on the C9000. What you may find is that if you charge 4 cells at 2000 then the charger may get a little warm, which also heats up the cells. To keep things slightly cooler, I tend to use 1600 or 1800 mA instead. But if you are not in a hurry, the default 1000 mA rate is fine too.

For an AAA Eneloop, 600 to 800 mA will be fine.

2. When I insert a AA, it sits level. When I insert a AAA, it first sits at an angle, with the positive higher than the negative. The charger detects it fine, but it looks like if I push a lot harder it will slot down to level. Is it supposed to be at that angle, or should I push down hard so it is level?

AAA cells in the C9000 are a bit tricky. You need to place the negative end first, press it down firmly, and then push down the positive end. I don't have the charger in front of me, but I am fairly sure the cell should sit right down into the slot.

3. What is the difference between top-off charging current (100mah) and maintenance charging current (10mah) ?

The top-off charge happens for two hours after a normal charge says "DONE". It helps the cells to get a fuller charge. The maintenance charge happens after that for as long as the cells sit in the charger.

Thank you

You're welcome.

[Niconical]

Thank you for all the replies

[TorchBoy]

So, putting it halfway between the recommended levels I will charge them at 1500mah, and the AAA at around 600mah, both around 0.7C.
...
3. What is the difference between top-off charging current (100mah) and maintenance charging current (10mah) ?

Accordingly, the maximum rate recommended for the Eneloop AA and AAA cells are, respectively, 1000mAh and 400mAh.

Charge rates are in mA (current), not mAh (capacity). I charge at 1000 mA and 400 mA (like Bones meant to say) for 2000 mAh and 800 mAh capacity cells respectively. If you want to spend less time charging them then use higher charge rates.

2. When I insert a AA, it sits level. When I insert a AAA, it first sits at an angle, with the positive higher than the negative. The charger detects it fine, but it looks like if I push a lot harder it will slot down to level. Is it supposed to be at that angle, or should I push down hard so it is level?

Yes, push harder, unless something is bent. You're inserting negative end first, right?

[pobox1475]

AAA cells in the C9000 are a bit tricky. You need to place the negative end first, press it down firmly, and then push down the positive end.

Also use the opposite motion for AA. Insert positive (top) end first, then negative (bottom).

[Mr Happy]

Also use the opposite motion for AA. Insert positive (top) end first, then negative (bottom).

Actually, I prefer not to do that as it can rip the plastic cell covering where it overlaps at the bottom. I prefer to insert and remove AA cells by pushing the cell down to compress the negative spring and allow the positive button to move freely in and out of the contact area.

[Black Rose]

Actually, I prefer not to do that as it can rip the plastic cell covering where it overlaps at the bottom. I prefer to insert and remove AA cells by pushing the cell down to compress the negative spring and allow the positive button to move freely in and out of the contact area.

That's what I do as well, even though the manual indicates the opposite.

[shuter]

You can't go wrong using a charge rate of .5C for all NiMH batteries including Eneloops. The C-9000 is a great product and I have found Maha customer service to be outstanding.

[Grayson73]

I just received the MH-C9000.

I have a lot of old cells. If I've understood what I've read in this thread, I should run a break-in or break-in + discharge + break-in rather than refresh&analyze 2x or 3x to revive old cells?

[krayzeemofo]

...
For an AAA Eneloop, 600 to 800 mA will be fine.
AAA cells in the C9000 are a bit tricky. You need to place the negative end first, press it down firmly, and then push down the positive end. I don't have the charger in front of me, but I am fairly sure the cell should sit right down into the slot.
...

I just got the charger today and I can confirm that it charges both at an angle as well as flush. I was looking at the charger itself, and it seems that it has 2 notches; perhaps one is meant for AAA, and the other for AA? That being said, I still wonder what the proper orientation is for AAA cells in the C9000...hm...

[fireguy]

Dude, what are you thinking of?! If you have cells that sit idle and want to replace them, get LSD cells like Eneloops. 2700's are possibly the worst cells you could buy unless you re-charge and use them daily.

I'd like to take a moment to show my ignorance of batteries here.

What is wrong with 2700's? I would have thought that the higher capacity would make them desirable? I understand the concept of LSD cells where the self-discharge is considerably less. Would a normal NiMH at 2000 maH be preferred over a 2700? Is it because of the self discharge, and taking a percentage of 2700 is larger than 2000? (eg: 10% of 2700 = 270, 10% of 2000 = 200) I am a noob here, so I hope my question isn't too silly .

[Black Rose]

I just got the charger today and I can confirm that it charges both at an angle as well as flush. I was looking at the charger itself, and it seems that it has 2 notches; perhaps one is meant for AAA, and the other for AA? That being said, I still wonder what the proper orientation is for AAA cells in the C9000...hm...

Yes, the different notches are for AA and AAA cells.

As for the proper orientation, it's noted in the manual, although I do not follow their recommendations.

I insert both AA and AAA negative end first and then push the cell down so the positive end of the cell makes proper contact. Less chance of torn wrappers.

[jayflash]

Maybe I'm not remembering correctly, but I thought it was established that a 1C charge rate was more beneficial for NiMH cells, which had already been broken in and in normal use, than a 0.5C rate. If that's accurate wouldn't charging an Eneloop or Hybrid AA cell be better at a 1500mA - 2000mA rate?

Thanks for any replies - I've gotta keep refreshing my memory.

[snakyjake]

I'd like to take a moment to show my ignorance of batteries here.

What is wrong with 2700's? I would have thought that the higher capacity would make them desirable? I understand the concept of LSD cells where the self-discharge is considerably less. Would a normal NiMH at 2000 maH be preferred over a 2700? Is it because of the self discharge, and taking a percentage of 2700 is larger than 2000? (eg: 10% of 2700 = 270, 10% of 2000 = 200) I am a noob here, so I hope my question isn't too silly .

From what I've read, it will take approx 6 months of self-discharge before a 2700 matches the LSD. Also read that 2700 may be more fragile if dropped, but don't have any evidence of this. Dropped on cement? Carpet? What if the battery is in my flashlight, will that protect the battery too? Too many questions, no good tests.

I'll be buying 2700 for my devices that I use often. LSD for devices that don't get used much.

...unless someone has evidence of 2700 problems, or can show evidence that LSD is superior in all ways.

[krayzeemofo]

Yes, the different notches are for AA and AAA cells.

As for the proper orientation, it's noted in the manual, although I do not follow their recommendations.

I insert both AA and AAA negative end first and then push the cell down so the positive end of the cell makes proper contact. Less chance of torn wrappers.

I must have missed it then, or perhaps my wording didn't convey what I meant, lol. Are the AAA cells supposed to sit at an angle with the positive side higher than the negative?

Thanks

[Black Rose]

Are the AAA cells supposed to sit at an angle with the positive side higher than the negative?

Good question. I use the lift rod on the back of the charger to allow more airflow around the charger.

I'll have to check when I get home, but I think the AAA cells might sit at a bit of angle if they are not fully seated.
Whenever I put AAA cells in the C9000, I always rotate them a bit to make sure they are fully seated.

[krayzeemofo]

Good question. I use the lift rod on the back of the charger to allow more airflow around the charger.

I'll have to check when I get home, but I think the AAA cells might sit at a bit of angle if they are not fully seated.
Whenever I put AAA cells in the C9000, I always rotate them a bit to make sure they are fully seated.

So then they are flush against the charger like AA cells? It just seems that in order to pop the AAA cells such that they are flush requires a bit of force when, to me anyways, it doesn't seem necessary when it seems to charge/function fine with the AAA cells at an angle/not parallel with the charger. The last thing I want to do is damage the cells or the charger which is why I am trying to find out what the official/generally accepted way of charging AAA cells is

Thanks


edit: I just noticed that you are located in Ontario, where did you get your C9000 and where do you normally get your battery/battery accessories? I ended getting mine from thomas-distributing, but was wondering if there was any place closer/in Canada other than paulsfinest.