Most Helpful Customer Reviews
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481 of 486 people found the following review helpful:
5.0 out of 5 stars
Battery charging and maintenance done right, October 25, 2005
Ni-MH batteries have become ubiquitous over the past decade. Their low cost and ever-increasing capacity make them a great alternative to alkaline batteries. Of course, you need to keep these batteries charged... And that's where things get complicated.
Charging Ni-MH batteries is the result of a compromise. A low current is gentle on the battery and maximizes its lifespan, but a full charge takes hours.
A high current will recharge the battery much faster, but put more strain on it, causing it to wear out prematurely. It also requires careful monitoring of the battery's electrical characteristics to prevent damage.
Most of the chargers you can find on the market today use one or the other of these methods. The fast chargers, especially the cheap ones, excel at one thing: destroying perfectly good batteries, because they lack the monitoring circuitry to control the charge current and detect when the battery is full. The slow chargers are usually better, mainly because it's harder to design a really bad slow charger. Unfortunately... they're slow.
The BC-900 is a completely different breed: it lets you pick the charge current for each individual battery, has very sophisticated monitoring circuitry that controls the charging process, and is also capable of "renewing" batteries by running full controlled discharge-recharge cycles.
I was a little skeptical that a fairly inexpensive product would be so thorough, but after reading all the 5-star reviews on Amazon I decided to give it a try. I'm glad I did: it's all it's cracked up to be, and more. I ran all my AA and AAA batteries through it; some of them had been destroyed by my previous charger, and it weeded those out right away; some were in pretty bad shape, but a refresh brought them back to life at almost full capacity.
The pleasant surprise was to find out all the freebies that come with the charger: four AA and four AAA batteries to get you started, four C-cell adapters, four D-cell adapters, and a nifty carrying case.
The less pleasant surprise: it can take several days to refresh batteries. I suppose this explains why the box didn't contain a cigarette lighter car adapter. Also, different batteries will take a different amount of time to complete a similar charging cycle. The charging slots being individually powered and monitored, it's not a real issue, since you can yank out any cell that's finished charging and insert the next one that needs recharging as soon as the little LCD screen warns you it's done.
As far as I know this is the best charger you can buy. It's reliable, gentle on the batteries, has useful capabilities not found on other models, and comes with a lot of extras. It's more expensive than your ordinary cheap slow charger, but the increased battery lifespan more than makes up for the price difference.
Highly recommended.
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586 of 595 people found the following review helpful:
5.0 out of 5 stars
Showdown: Maha MH-C9000 vs. La Crosse BC-900, September 16, 2007
I have a La Crosse Technology BC-900 AlphaPower Battery Charger since nearly two years ago, and I'm very happy with it. When the Maha Powerex MH-C9000 WizardOne Charger-Analyzer was announced, its looked even better on paper than the BC-900. So I also bought the C9000 one month ago. Here is my assessment for those two chargers:
First, let's get the similarities out of the way. Both the BC-900 and the C9000 are powerful battery analyzers/conditioners which can also be used as your everyday battery chargers. Both chargers accept one to four AA or AAA cells with independent charging currents. Both come with universal (100-240V AC) adapter.
Next, the differences:
1. SIZE:
First thing you'll notice is that the Maha C9000 is HUGE for a 4-AA-cell charger. It is about twice as large as the BC-900 (see my Customer Image for size comparison).
Larger size makes the C9000 less suitable as a travel charger. However, as a home charger this is actually an advantage. Extra spacing between cells allows better cooling, and also makes it easier to remove individual cell.
2. CHARGING CURRENT:
The BC-900 can provide charging current from 200 to 1000mA for 4 cells, or up to 1800mA for two cells. The C9000 can charge from 200 to 2000mA for all four cells. So if you routinely need to charge cells in a hurry, the C9000 is better.
However, due to the complicated key sequences involved (for example, to charge 4 cells at 2000mA, you need to punch in 48 key strokes!), most sane people will probably leave the C9000 at its default current of 1000mA.
3. DISPLAY:
The BC-900 has a 4-column LCD panel that shows the status (capacity, voltage, current, or time) of all four cells either simultaneously, or individually. The C9000 sports a LCD display with back-light. It is BIG, it is BRIGHT, and it works really well - as a NIGHT LIGHT!
The biggest problem with the C9000's display is that it can only show one status for one cell at any one time. It constantly toggles from one status to another, then from one cell to the next. If you have 4 cells in the charger, it takes 48 seconds or more (depending on the current activity) for the display to cycle through all 4 cells. There is also no way to pause the display. So if you missed one reading, you have to wait for it to cycle through again.
4. ANALYZING / CONDITIONING FUNCTIONS:
The BC-900 has an easy-to-use 'DISCHARGE/REFRESH' function that can be used to recondition old cells. The C9000 has a similar function called 'CYCLE', but it is very tedious to use (see the USER INTERFACE section for details).
In addition, the C9000 also has a 'BREAK-IN' mode which supposedly should be applied to new cells before first use, or to really old cells that have not been charged for years. Beware that this operation takes at least 39 hours to complete, so I doubt many people would actually use it.
5. DEAD CELL DETECTION:
If a cell is completely drained (battery terminal voltage drops below 0.5V), the BC-900 thinks it is shorted and therefore refuses to charge it. This has caused a lot of frustrations among users, but there is a way to work around it (see my BC-900 Customer Image for details). The C9000 is smarter in this aspect. If the battery terminal voltage is too low, it automatically starts charging at 125mA until the voltage rises above 1V, then it continues with the programmed charging current.
The C9000 also measures battery internal resistance when a cell is first inserted. If the user inserts an alkaline cell (which has much higher internal resistance), the C9000 displays 'HIGH' and refuses to charge it. This is a good safety feature, except that it also incorrectly rejected most of my NiMH cells bought four or five years ago. So I cannot use the C9000 to charge or recondition those old cells, even though the BC-900 reports that they still have around 1000mAh of capacity left.
6. USER INTERFACE:
With the BC-900, you can select the operation and current for all cells simultaneously, or you can change them indivdually by using the cell-selection buttons. The only limitation is that once the charging current is fixed, you cannot subsequently select a larger current without removing all cells.
The C9000 has four completely independent charging circuits that can be programmed to different currents. This may sound great at first, but in practice it soon becomes a burden, because you often need to press dozens of key stokes to program all four cells.
For example: If you want to recondition four cells on the BC-900, you'll go through the following sequence:
- insert in all 4 cells at once
- press MODE to select DISCHARGE/REFRESH (2 keystrokes*)
- press CURRENT to select charging current (2-3 keystrokes)
* Note: need to press and hold MODE for 1 second for the first keystroke
On the C9000, you can insert in all 4 cells at once, but you have to program them one at a time. Which means:
- press UP/DOWN to select 'CYCLE', then 'ENTER' (2-5 key strokes)
- press UP/DOWN to select charging current, ENTER (1-11 key strokes)
- press UP/DOWN to select discharging current, ENTER (1-6 key strokes)
- press UP/DOWN to select number of cycles, ENTER (1-13 key strokes)
Congratulations! You just finished programming the first cell. Now repeat that for the other three cells.
BOTTOM LINE:
The Maha MH-C9000 is, without a doubt, the most powerful NiMH AA battery analyzer/charger in the consumer market. However, certain design issues (such as a single-status LCD panel and ridiculously long programming sequences) make it difficult to use for multiple cells. For most of my routine charging and maintenance of NiMH cells, I'll continue to use my old La Crosse BC-900.
Nevertheless, I don't regret buying the C9000, because it was a lot of fun for me to try out all its functions. Plus I now have a really cool (but expensive) night light.
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85 of 88 people found the following review helpful:
5.0 out of 5 stars
Really cost effective and well designed, February 19, 2007
I must say that I thought all chargers were more or less the same. After purchasing a myriad of chargers and batteries I now realize that the various batteries and chargers make all kinds of silly claims that rarely meet expectations. I use AA NiMH batteries for some electronic devices (mice, radios, etc.) and my two Canon cameras. Since my S2 and S3 cameras have a healthy appetite for batteries I decided to check out some reviews and buy from Thomas-Distributing. They are an excellent, if pricey, source for rechargable batteries and chargers. The array of choices is dizzying. I now own two LaCrosse BC-900s that I purchase from Amazon at a much better price. Thomas-Distributing also sells the full line of Maha chargers that seem to garner top ratings but I think the Maha model that is similar to the LaCrosse, costs more and offers fewer features. I own two lower-end Maha chargers and I think they are great. But, the flexibility and information offered by LaCrosse makes this model the best and quite possibly the only charger for AA/AAA batteries that you will ever need. The AC adapter is external and adds bulk so this charger is perhaps less compact than those all-in-one plug in the wall types. But the features built into this model make this my absolute favorite. Other chargers require that you charge two batteries together and the LaCrosse allows you to charge up to four batteries independently at separate rates using separate functions. This is important if you have different batteries with different capacities. The display allows you to monitor each battery for current/time/voltage/capacity side by side. This way you can refresh one battery while discharging one battery while charging one battery... you get the idea. Unlike the Maha model, the display shows all four battery status levels side by side. No scrolling through menus for each battery one by one. At a glance you can check each battery and compare it to the next battery. Most chargers from department stores or camera shops are designed to rapidly charge the battery within a few hours. The high current does charge more quickly but generates heat and reduces the effective life of the battery. Furthermore, those blinking lights don't have accurate meters so you have no information about the true capacity and no idea about the condition of your batteries. Some chargers have a conditioning button which discharges and recharges but still does not give any accurate information. The LaCrosse lets you charge, discharge, measure, recondition and effectively revive batteries. I usually use the lowest default current and refresh my batteries over one week. This takes time but brings my batteries to full capacity. The maH capacity of the battery printed on the battery is often overstated so here is your chance to compare the brands of batteries. (I think the Powerex and Sanyo batteries from Thomas-Distributing are the best.) If you are in a big hurry simply choose a higher current and rapidly charge your batteries. Did you know that any device using multiple batteries will have a battery life limited by the battery with the lowest capacity? Let me explain, If you have four AA batteries that state 2400 maH capacity each, if one battery is weaker than the true 2400 mah (lets just say 1800 maH) then the combination of all four batteries in your device will function to a capacity of only 1800 maH. I'll illustrate... bought four expensive 2400 maH batteries and found that they would run out faster than my old 1800 maH batteries! Using the LaCrosse I discovered that one battery had a capacity of only 1500 maH and the other three were about 2200 maH. I refreshed all four and they all exceed 2500 maH now! Now I take several hundred photos on a single set of batteries. After purchasing eight chargers and throwing away most of them, it's clear that this is the one charger that really shines. It will save you money by reviving old batteries. The price is great and the charger comes with a set of AA and AAA batteries. The included battery adapters may come in handy in an emergency if you need C batteries for a flashlight or toy. My only complaint is the external AC adapter which makes it less portable; I think this is really a minor quibble. If you prefer a rapid charger without all these features check out Maha. Hope this helps.
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