www.imaging-resource.com/ACCS/BATTS/BATTS.HTM
I still havent gotten around to the extensive charger test I want to do, the time pressure from more mainline projects has just been too great. Im getting a little tired of saying this every time I do an update to the battery shootout page, but the battery/charger testing is unfortunately little more than an unfunded hobby that I have to squeeze in around my primary work of camera/scanner testing. For now, my standard recommendation is still the Maha C204 charger, with one or two Maha 2A4 trickle-charge units to top off the batteries for those of you who absolutely must have the last possible iota of juice crammed into your batteries. Overall, it still seems that chargers can charge fast, completely, and gently low battery temperatures, but you can only pick two of the three characteristics. Mahas new 401FS does an excellent job as well, but doesnt have the discharge-conditioning circuitry of the C204. Even though Maha claims that the flex-pulse charging of the 401FS eliminates the need for discharge conditioning, I still like having a discharge option. Apart from this, the 401FS is an excellent charger, giving you the option of either fast charging with moderate temperature rise, or a roughly 5-hour charge cycle with very gentle temperature profile. Another excellent charger seems to be the Lightning Pack 4000N from RipVan100, which is more in the fast/gentle camp although its overnight trickle charge does a good job of topping-off batteries, whereas the C204 is in the fast/complete category. The RipVan 100 has the advantage of not needing any external power adapter, since it has a power plug built in, and can operate from 110-240volts with no adapter needed. There - I just saved you reading the rest of a long, boring article!
The good news is that theres new or updated data on nine more brands/capacity combinations, including most of the latest round of 2000 and 2100 mAh cells. The test setup continues to do very well, with the soldered connections and added clamps for the battery holders. Ive also recently switched to a metal-and-fiber battery holder design that is much more rugged than the previous spring-steel-and-plastic unit. Accuracy doesnt seem to be impacted, but the new holder is much more rugged, eliminating the hassle of replacing the test socket every month or so. Run to run consistency continues to be better than 1 on virtually all runs. As noted above, the new 2200 mAh Powerex cells from Maha are the new leaders in the Watt-hour derby, but my measurements are based on a single set of cells, so hold the confetti for a little while, until I can verify the results with further testing of additional units. Nexcell does indeed appear to have fixed the cathode problem in their 1800 mAh cells, as my retest of these units showed none of the early failure syndrome I observed previously. I saw some evidence of cathode limitations in their 2000 mAh cells, but not nearly as severe as with the previous 1800s. Ive had to drop all attempts at a charger test protocol, at least for the present, as Ive barely had time to keep up the basic battery testing in the face of ongoing digicam review overload. The problem is that charger behavior seems to vary a fair bit with the cells being charged. Completeness of charge seems to be fairly consistent across multiple battery models, but temperature profiles are all over the map. A charger that seems to overheat one brand/model of battery does just fine on others. On the other hand, an otherwise well-behaved charger will overheat one particular brand/model of cell. Some chargers do seem to be hotter or cooler than others, but its tough to develop the level of objective quantification I like to see in my reviews. As alluded to earlier, one important, albeit somewhat informal finding at this point: The Rayovac 1-hour charger does indeed seem to get the batteries too hot.
In practice, I found that the highest current drain that the iPowerUS cells could tolerate without damage was something on the order of 500 mAh or less. This is a good bit below the current demanded by many digicams operating in capture mode with their LCD turned on. While it may be customary for many digicam owners to use their cameras in an intermittent fashion, I dont think it makes sense to use batteries that can be damaged by occasional continuous usage. The iPowerUS 2100s could be a good choice for shooters having less power-hungry cameras, but these arent the users wholl be most desirous really high-capacity batteries. I also observed that long-term trickle charging 25-50 mAh was damaging to the iPowerUS cells. I dislike this, as its my common practice to just leave a few sets of cells in low-rate trickle chargers all the time, as a way of keeping them topped off. While this isnt a mandatory usage, not being able to keep a few sets of cells topped-off all the time makes battery management more of a chore to deal with. The problems with high current drain were so bad with these cells that I resorted to testing them at half load, really an unfair comparison to the rest of the batteries on the chart. Because these batteries showed such variable performance through their relatively short lives, I chose to put them fairly low on the chart, located at the point theyd reached at the end of my testing. One final note - The best use of the iPowerUS 2100s might be to simply view them as semi-disposable batteries, simply accepting the fact that theyre going to need to be replaced after a dozen or charge/discharge cycles, along with the fact that you cant trickle charge them for more than a day or so at a time. In that usage, theyd be a good bit more expensive than other NiMH cells, but still vastly cheaper than alkaline batteries.
Final note - As of this writing, the latest Sanyo and Powerex and apparently Jetcell cells deliver more power over many cycles than do the iPowerUS 2100s over their rather short life. In light of this, I dont see any reason to use the iPowerUS cells. Pay a bit more for Powerex 2200s, Jetcell 2100s, or Sanyo 2100s, and youll save money in the long run. Introduction Apart from the camera itself and a sufficiently large memory card, batteries are probably the most critical element in your entire digicam equipment kit. Choose the wrong batteries, and you can be left with a camera thats no more than an expensive paperweight, when that once-in-a-lifetime shot appears. Some cameras come with custom-designed rechargeable LiIon battery packs in the box - If you own one of these, theres no issue of which brand and type of batteries to buy, just be sure to get an extra battery pack and keep it charged as a spare. A great many digicams use conventional AA-size batteries though, which opens a whole Pandoras box of potential battery issues. Let me go on the record right away though, that I generally like AA-equipped cameras, as it makes packing spare batteries a much more affordable proposition.
For the AA-equipped cameras, its well established that standard alkaline batteries are almost completely worthless in most cases. Hopefully all my readers have been thoroughly indoctrinated in the need for high capacity NiMH rechargeable AA cells and a good charger. As well see though, theres quite a range of performance between brands and models of NiMH batteries. And even more variation between chargers, but thats a subject for another review altogether. Given the importance of NiMH batteries to digicam operation, I resolved to test as many as I could get my hands on, to sort out battery performance once and for all. In typical Dave-fashion, I couldnt be content with anything simple or straightforward, and so built my own test system, with a microcontroller and A/D converter to collect all the relevant data. It turned out to be a good thing that I went to such extremes, as I discovered that less-involved test protocols would have yielded inaccurate results. The result is whats surely the most comprehensive study of NiMH battery performance thats been published anywhere accessible to the general public. As new battery models appear on the market from time to time, Ill add to this article to incorporate their data as well. Even t...
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