Maha C9000 vs. AccuManager 20

[snakyjake]

I've been reading 100's of posts, and most all rate the Maha C9000 #1. But reading post, I can't help notice that AccuManager 20 is beating the Maha C9000 "improved", yet I haven't seen the AccuManager 20 popularity.

Why not? Is it just because the C9000 is providing more information? Or does it do a better job charging? Or help care for the battery's life?

At this point, I really can't see why the C9000 "improved" is recommended over AccuManager 20.

Thanks,
Jake

 

[SilverFox]

Hello Jake,

I think you will have your answer if you research the features of each charger.

The AccuManager20 charges cells.

The Maha C9000 does that, and a whole lot more.

Tom

 

[snakyjake]

Hello Jake,

I think you will have your answer if you research the features of each charger.

The AccuManager20 charges cells.

The Maha C9000 does that, and a whole lot more.

Tom

When I examine the features of a charger, here's the main features I look at:

1. Provide the maximum mAh.
2. Gentle on the batteries.
3. Separate charging bays.
4. Charge A/AAA.
5. Quality/Price.
Everything else similar.

When I read the charger shootout, the AccuManager beats the C9000, therefore wins feature #1.
Both AccuManager 20 and C9000 are gentle on batteries, tie for #2.

AccuManager 20 will let me charge C, D, 9v batteries.

The only feature C9000 can do that AccuManager does not is provide Ah info.

Other than that, the rest seems like marketing by both manufacturers.

Do I need 5 modes if AccuManager is top for maximum charge?
Do I care what algorithm the chargers used? No, the charger shootout tells me which algorithm is best.
Do I need break-in? Didn't think I need this for NiMH. Thought this was more for NiCd.
Do I need refresh? Didn't think I need this for NiMH. Thought this was more for NiCd.

But the main point is that the charger shootout provided evidence that the AccuManager 20 can outcharge the Maha C9000 "improved".


Feature Info

AccuManager 20 Features:

* The NEW AccuManager20 universal battery charger automatically recognizes the battery chemistry type.
* Batteries can be charged in any combination of battery chemistry at the same time.
* Designed with Six Charging slots with over-voltage and reverse polarity protection, recognition of defective batteries- (lets you know if a battery is defective), automatic float charge and self protection disconnect.
* The Automatic Float Charge can often revive batteries that have been stored for long periods of time and are unable to be charged in other types of chargers.
* Will charge any capacity of AA, AAA, C, D, or 9V Rechargeable Battery, even the higher capacity rechargeable batteries of the future.
* 2 Proprietary micro-controllers regulate and monitor the most important battery characteristics during the complete recharging process in all 6 charging channels - Yes, even the 9V batteries are monitored and regulated!
* Battery-Maintenence -System (ACX Intelligence) Complete refreshing function prevents memory-effect in new batteries and overridden in older batteries. The regeneration of your batteries is conducted automatically without prior discharging.
* Able to charge any combination of four AA, AAA, C, D and either one or two 9V Batteries Simultaneously
* Charge rate: AA, AAA, C, and D - 1.8V@700mA Max - 9V - 12V @ 30mA Max
* Separate LEDs for each charging channel - six channels in all.
* LEDs show charging status at all times.
* Includes AC 110V Power Adapter and a 12V Car cord for mobile operation.
* Fully recharges high capacity batteries.. regardless of the batteries capacity and will charge even higher capacity batteries of the future.
* Three Year Limited Manufacturer Warranty.


Maha C9000 Features
* The Maha MH-C9000 Advanced Battery Charger can Charge, condition and analyze one to four AA or AAA rechargeable batteries with Independent operation of each battery slot.
* The Maha MH-C9000 Charger has a Large backlit LCD. Bright white LED light for easy to read the MH-C9000 display.
* Digitally displays capacity, voltage, time elapsed and current.
* Adjustable charging rate from 0.2 to 2.0A and discharging rate from 0.1A to 1.0A.
* Five modes of operation:
-- Charge: Charge the battery at the selected rate
-- Discharge: Discharge the battery at the selected rate.
-- Analyze & Refresh: First charge the battery at the selected rate, then discharge it at the selected rate followed by recharging. The discharge capacity is saved for display at the end of the cycle.
-- Break-In: Allows user to enter the battery capacity and performs a forming charge at 0.1C for 16 hours (using only temperature and timer cutoff) followed by discharge and medium rate recharge.
-- Cycle: Allows user to set charge and discharge rate and number of cycles to perform. The MH-C9000 will save the capacity for up to 12 cycles which user can access throughout the cycling.
* Negative delta V, peak voltage, dT/dt (temperature rise) and max
* The MH-C9000 Battery Charger has excellent Temperature protection
* Four independent thermocouples to manage rechargeable battery temperatures.
* Quartz-oscillator time base for 1% accuracy in capacity calculations. The capacity is determined by continously integrating the measured current (actual current not set point) over time. High accuracy is achieved by using a precision shunt-resistor coupled with a 12-bit Analog-to-Digital converter as well as a quartz oscillator timebase.
* The MH-C9000 will charge and analyze all current NiMH Rechargeable Batteries as well as Future NiMH Rechargeable Batteries regardless of capacity.
* Built -In Trickle Charge -- 10mA trickle charge rate -- using modulated pulse trickle charge.
* The MH-C9000 will charge and analyze the New Sanyo Eneloop Low Discharge NiMH Rechargeable Batteries as well as all other Low Discharge NiMH Rechargeable Batteries.
* 12V input and can be powered by an optional car adapter
* 100~240V AC Lightweight ( 170gr (6oz) )Worldwide switching power supply.
* Rugged construction with extensive ventilation for the batteries.
* Built-in "lift rod" to raise the charger to improve air flow below the unit.
* The MH-C9000 Charger can be operated in a "Basic" or in "Advanced" mode. In the Basic mode, you merely need to insert the batteries into the MHC9000 with no further key presses. The Maha PowerEx MH-C9000 charger will select the appropriate settings automatically, making it suitable for the casual users.
* In "Advanced " mode you can actually Program the MHC9000 Battery Charger to your Charging and discharging Specifications. See the Programming Diagram below.

 

[SilverFox]

Hello Jake,

It sounds like you have decided that you don't need the additional features offered by the C9000 and are happy with those offered by the AccuManager20.

If you only need to charge cells, the AccuManager20 is a great charger.

On the other hand, if you are interested in analyzing the performance of your cells, the AccuManager20 falls short on that. If your cells start acting a bit sluggish, you won't be able to run a refresh, or run a standard charge and discharge to check the capacity of the cell to see if it is dieing, or is just a little bit sluggish and can be revived.

Using the AccuManager20, when you find your cells acting a little sluggish, you can simply recycle your cells and get some new ones.

New cells benefit from a break in cycle. Cells that have been in storage benefit from a break in cycle. All cells benefit from a refresh cycle every 30 days.

By choosing the AccuManager20, you will end up with around a 2% increase in capacity, if your cells are in tip top condition, and you will have a very simple charging system. Charge the cells up. If they don't work properly, recycle them and get some new cells.

If you get a C9000, your options expand and you will end up spending a little more time involved with your batteries. When you get new cells, you can run a break in to make sure your cells are performing according to specifications. When you discover some cells in the back of a drawer, you can analyze them to see if they are worth keeping. When putting together a light that uses multiple cells, you can match your cells for maximum performance.

All of this requires a little bit of involvement with your charger, and a charger that is capable of giving you the information you need.

The exciting thing is that you get to choose which charger you want, and the level of involvement you want to have with charging your batteries.

Tom

 

[snakyjake]

Tom, thanks for the replies. Haven't yet decided what I want. Just trying to understand the differences so I can make a better informed choice. I'm betting that others have gone through the same decision making, and perhaps have both chargers and have real performance tests. The charger comparison post is just a performance test, however, it does not test all the other features.

Is there evidence that the AccuManager 20 does not adequately refresh/break-in batteries? According to the marketing, "ACX Intelligence" is supposed to "prevent memory-effect in new batteries and overridden in older batteries. The regeneration of your batteries is conducted automatically without prior discharging."

It sounds like the ACX feature is the same thing as Maha's refresh/break-in feature.

I can see the analyze feature of the Maha being useful. I've been curious on why there's not a simpler device. I just want an analyzer to drain a predetermined amperage and run a clock. When the clock stops, it shows how many amp hours. Should be simple and cheap, although difficult to find cheap.

What is the feature called for matching multiple batteries? I don't see that listed for the Maha, and not sure how I can find out if or not the AccuManager can do the same. I'm also curious on how that works. If I have one cell at 2000 mAh, and another at 1900 mAh, what do I get if I match?

I hope no one sees me as being too nitpicky....but I am a critic

Thanks,

Jake

 

[45/70]

I hope no one sees me as being too nitpicky....but I am a critic

Nothing wrong with that.

If I'm not mistaken, the "ACX Intelligence" is just AccuManager's name for "negative pulse" or "burp charging". There are a lot of people that don't really think it does anything. It doesn't seem to hurt though. A lot of charger manufacturers still use it, Maha I think does, in some of their chargers, the C.Crane, and a bunch of others, as well. Also, no, ACX is not the same as refresh and analyze, or break in on the C-9000.

The AccuManager doesn't perform an IEC spec break in charge at all. The C-9000 does, or at least very close to it.

As far as matching batteries, this is easily accomplished with the C-9000 by determining the capacity of cells, something you can't do with the AccuManager. What I do (my battery collection of AA's is in groups of 20) is number them from 1-20 in order of lowest capacity to highest. Then, when I go to use cells in series (or parallel, for that matter), I just make sure that the group I use consists of consecutive numbers. It's ideal if the cells are within 2% of each other, but you can get by with 5%.

I'm not saying the AccuManager is not a good charger, I'm sure it is. The C-9000 just has more features to accomplish battery charging and maintenance. More bells and whistles, so to speak. Of course, it only works with AAA's and AA's, that may be a drawback.

Dave

 

[LightScene]

The C9000 lets you discharge your batteries slowly and to the correct point, something you can't really do any other way. Then you can recharge them slowly and this restores capacity that would otherwise be lost. This is what they refer to as a refresh cycle. This is why I decided to get the C9000.

 

[coppertrail]

I own the C9000 and the MH-C800S. The reason I mention this is that even though the C8800S uses a "pulse charging" algorithm, it also has a conditioning mode which is the equivalent of the refresh mode on the C9000. I find that the conditioning mode combined with the pulse charging does a good job with my cells, most notably LSD cells. I use the C9000 for my higher capacity cells as it offers higher charging rates: I like to charge between .5 and 1C.

 

[snakyjake]

The C9000 lets you discharge your batteries slowly and to the correct point, something you can't really do any other way. Then you can recharge them slowly and this restores capacity that would otherwise be lost. This is what they refer to as a refresh cycle. This is why I decided to get the C9000.

What you describe is what I thought is "memory effect" on NiCd batteries only, not NiMH. Could be wrong about that.

This is all good information. I'm learning that there's more to batteries than just the batteries and the charger.

 

[snakyjake]

I think what also is confusing is what technology/methods are optimum for NiCD charging vs. NiMH. Some of the features may be more to optimize NiCD charging, while not be necessary to optimize NiMH.

I would think the refresh, break-in, and ACX, negative pulse charging would be to the benefit of NiCD charging, and not NiMH.

Or to state differently, a charger may have lots of cool sounding features, but only to benefit NiCD.

Are there any features of the Maha/AccuManager that are only to benefit NiCD charging? I'd like to separate out the features I won't be using for NiMH charging.

Thanks again,
Jake

 

[coppertrail]

Bookookmark Battery University, tons of valuable battery related info. and more specifically, the article on memory effect.

 

[45/70]

Interesting article about the memory effect, coppertrail. Somehow, I've missed that on my frequent visits to B.U.

It appears that the jury is still out on negative pulse charging, after 40 years. I, not too long ago, saw an article done by a corporation, or some such entity, that did a study on negative pulse charging, and their results were that it had no benefit. I can't remember where I saw it, but it was done in the last 5 years or so. Their solution for large crystalline formation was the slow discharge referred to in the B.U. article. As I stated in my previous post, I'm certainly not against it, my C. Crane has it, and it has worked very well for me. It will eventually be replaced by a C-808M, which has it as well.

One thing I might point out, is that the Maha 80x series can, in fact, perform a refresh cycle, however the C-9000 has adjustable parameters that the C-80x series do not. Just a bit more flexibility, with the C-9000.

snakyjake, I'm not trying to convince you one way or the other. I almost bought an Accu Manager myself, a few years back (I ended up with the C. Crane/Saitek instead). Again, I'm sure it is a good charger. My purpose is to point out the "extras", that the C-9000 offers, and why they can be useful, if, you want such features.

Dave

 

[snakyjake]

Bookookmark Battery University, tons of valuable battery related info. and more specifically, the article on memory effect.

Good reading material...thanks!

 

[snakyjake]

snakyjake, I'm not trying to convince you one way or the other. I almost bought an Accu Manager myself, a few years back (I ended up with the C. Crane/Saitek instead). Again, I'm sure it is a good charger. My purpose is to point out the "extras", that the C-9000 offers, and why they can be useful, if, you want such features.

Thanks Dave. That's exactly the kind of info I'm looking for. Some of the info is for to make my purchase, the other is curiosity, and the other is to know what the heck I'm doing.

The charger comparison post is a great for testing of the chargers. Perhaps we need to see another test of older batteries to see which "refresh" algorithms work. But from the post, it seems the AccuManager is ahead of Maha, for whatever reason or technology, for frequently used NiMH battery that was mentioned in the post.

From this post, I believe I'm learning that what truly makes the Maha a better charger is that it can analyze.

I have not found any tests that can demonstrate the value differences between Maha and AccuManager.

For me, it's all about runtime and how long I can make a battery last. The bonus is being able to analyze the battery to have real numbers to show performance.

Jake