She is the workhorse of battery chargers; the other racehorses lost their legs long ago.
Written: Oct 17 '07
|
Product Rating:
|
|
|
Pros: Regardless of capacity, recharges any NiMH AA/AAA or 9 volt battery.
Cons: Must unplug to restart charging cycle, 15 hour recharge
The Bottom Line: A simple, well built AA, AAA and 9volt battery charger that will give you years of service.
|
|
|
| rgathright's Full Review: Energizer CHM4AAWB NiMH/NiCD Battery Charger (auth... |
The Energizer CHM4AAWB is a wall hanging style battery charger that offers years of dependable service and will save you hundreds if not thousands of dollars in the process. The unit comes with two low capacity AA NiMH batteries. NiMH batteries have a higher amperage rating than NiCad batteries and should be considered by anyone using portable electronics. The only drawback is the 15 hour recharge time. I use this battery charger to charge the AA NiMH batteries in my Sony D-NF340 Personal CD Player and the AAA NiMH batteries in my Dorcy 41-4281 1-Watt Luxeon LED Flashlight.
Operation
To use this battery charger simply place either two AA or AAA batteries, positive side up, into the front metal clips.
9 volt batteries can be charged individually. Next place the unit in any 120VAC outlet and wait 15 hours for the red LED lights to go out.
How does rapid battery charging affect performance?
There are some factors to take in to consideration when comparing fast charging versus slow charging, but basically as long as you have a good quality charger that does not literally fry your batteries, it all boils down to your needs and preference.
Basically to use a simple analogy, fast charging is sort of like when you drive your car at higher speeds, you get to your destination faster but there is a little more wear and tear on your vehicle. However on the other hand when you drive your car slower you will get to your destination a little later with less wear and tear on your vehicle. But in the end the differences won't matter much.
NiMH batteries, like your car, will normally have a longer useful life if they are not abused, and are charged using a good quality charger, whether or not it is a fast or slow type charger. As for the number of charges you can expect between the two this is very difficult to say.
Quick charging is always harder on the batteries, because of the higher current, which causes more heating, which degrades the chemistry of the battery faster. The trade off, of course, is the speed of the charge. Quick charging will, in fact, reduce the life of the battery. It actually depends on the quick charge profile. If done right in a three stage process with temperature sensing to limit the first stage (1C to 90% capacity), the life of the battery won't be adversely effected. Low charging temps (less than 15 degrees C) will hurt your batteries. Internally, when the battery overheats the electrolyte is literally burnt off. Just like a car battery, the less electrolyte you have the lower the charge capacity. In fact, if you have a rechargeable battery that is leaking you should throw it away because it will never reach a full charge and at the same time the excessive current demands can overextend any other battery simultaneously being charged as well!
Construction and Appearance
The all black case of the Energizer CHM4AAWB is made of thick plastic. Two red LED indicator lights on the face of the unit let you know if a charge is taking place. My favorite design feature is that on a two plug, grounded wall outlet, you can plug the charger in the lower receptacle and use the three prong plug from a Sony BRAVIA KDL-40XBR2 40in. HDTV LCD Television in the top receptacle. Efficient case design is the number one reason why four years later, I am still using this battery charger.
The metal contacts that touch the positive and negative sides of the battery are made of a heavy gauge metal. As a result, the contacts do not lose their tension ensuring that the battery is firmly held in place every time. Some battery chargers use weak metal contacts, after a dozen uses you have to bend the metal back into shape to get the batteries to charge.
The charger can hold a total of four AA or AAA in sets of two or two 9 volt batteries. Yes, you can charge a set of two AA and two AAA batteries at the same time.
Included Accessories
One battery charger, two AA Energizer brand NiMH batteries and an instruction manual.
Summary
Overall, I am very satisfied with the performance this battery charger. The process of unplugging the unit is annoying and led to my four star rating, but everything else about the unit is great! You would feel the same way if you had to pull a bulky piece of plastic out of the wall every time a battery was drained. Many people ignore slow battery chargers in today's fast paced world. However, if you understand how batteries operate and the reduced life associated with fast recharge times, a slow battery charger is minor inconvience. Finally, let me confirm that you can charge batteries with up to 2500Mah capacity in this unit.
Reference
Details on NiMH battery performance: http://data.energizer.com/PDFs/nickelmetalhydride_appman.pdf
Recommended:
Yes
|
|
|
|
Epinions.com ID: rgathright
|
|
Member: Reuben Gathright
Location: Lake Charles, LA
Reviews written: 214
Trusted by: 128 members
|
|
|