Posts Tagged ‘Powerex


The 1.2V AA 2400 mAh Powerex Imedion NiMH batteries are of the Low Self Discharge Type (LSD NiMH) and are considered to be among the best high capacity and high performance LSD NiMH batteries by many, competing with the like of Sanyo Eneloop for example. These batteries are rated at 2400 mAh typical and 2250 mAh minimum guaranteed capacity and the fact that they are LSD means they are supposed to loose not more than 15% of their capacity per year of storage. They also come pre-charged and can be recharged up to 1000 times. But let us see how good will they perform in our tests and see if they will manage to hold up to their reputation well or not.


Starting the tests of the 1.2V AA 2400 mAh Powerex Imedion NiMH batteries with a low constant current discharge rate of 0.2A got us 2414 mAh as or with other words we are getting a bit over the typical capacity that they are rated at, so a good start. Increasing the load to 0.5A these batteries still manage to provide capacity higher than their minimum rating of 2250 mAh, so more good results here. And going with even higher constant current loads of 1.0A and 2.0A we are still seeing very good results in terms of useable capacity. So in short, meeting their rating and providing more than good results in both low and high load applications and while not as good as Sanyo Eneloop XX in terms of capacity they are also a bit cheaper than the Eneloops. Anyway, these batteries are very good for what they are rated at and for their price, so you cannot go wrong getting them.

The performance of the 1.2V AA 2400 mAh Powerex Imedion NiMH batteries in our tests:

– 2414 mAh at 0.2A load
– 2283 mAh at 0.5A load
– 2168 mAh at 1.0A load
– 1917 mAh at 2.0A load

– 3.002 Wh at 0.2A load
– 2.781 Wh at 0.5A load
– 2.535 Wh at 1.0A load
– 2.099 Wh at 2.0A load

If you are using various kinds of rechargeable batteries you might have trouble keeping them all in shape and maximizing their performance and life, the more the batteries, the harder it is and we are not talking only about NiMH batteries, but LiPo, PB as well as other various kinds. For example if you only use a couple of NiMH batteries, then probably a simple and slow charger could do a good job, but if you are using many batteries and not only NiMH, but also Lithium-based rechargeable ones you might want to get a more serious charger or even multiple charger in order to properly maintain and take full advantage of the rechargeability of your batteries. You probably have seen that rechargeable NiMH batteries offer up to 1000 recharge cycles and Li-Ion and LiPo batteries can go from anywhere between 100 and 500 cycles if properly used and maintained. But in reality most people literally kill their rechargeable batteries in just about few dozens of recharge cycles due to improper maintenance and it is very often due to a problem with forgetting to recharge or overcharging or discharging them. In order to fully utilize the potential of the rechargeable batteries and also do what they are supposed to – help nature by avoiding the use of so many primary batteries like Alkaline for example or even worse Carbon-Zinc ones, you need to pay some attention and use better chargers in order to maintain and use the batteries as they are intended to be…


We are starting with the MAHA Powerex MH‑C9000 WizardOne Charger-Analyzer, probably the single best charger for NiMH batteries out there. But this is more than just a charger for AA and AAA size NiMH and NiCD batteris, because it can not only Charge but also Refresh and Analyze, Break-In, Discharge and Cycle the batteries in order to maintain them in the best possible shape. The device has four independent channels, one for each battery, thus allowing you to have a different function for each of the battery you have there or just to work with a single or more batteries at the same time. The standard charging current is user selectable from 0.2-2.0A (200-2000mA) and the discharging currents can be between 0.1-1.0A (100-1000mA) in increments of 0.1A and you can of course have different current for each channel. Thanks to the extra functions besides the standard charge and discharge you can use this to always maintain the health of your NiMH/NiCD batteries, even if they are not used for a while or they were not properly charged or discharged for some time. The charger is great both in terms of functionality, reliability and quality and the only better thing than getting one Powerex MH‑C9000 is to get two in order to be able to have 8 slots and nit just 4 with a single one – that is especially useful if you have and use a lot of AA and AAA size rechargeable batteries. In fact we are using one of these chargers as a part of our test equipment and are planning to get a second one in the near future. If you manage to find the Memorex Pro Genux 1 charger you could have a chance to get the Powerex MH‑C9000 for less as this is a rebranded version of the MH‑C9000, so grab a better deal if you can with the rebranded model.


Now, if you need a good charger that can quickly properly charge and maintain a larger number of AA and AAA size NiMh/NiCD batteries the Powerex MH‑C9000 might not be the best choice with its only 4 channels per device. Yes, it does have more extras, but with the significant increase in the number of batteries having a more functions with menus and options could turn out to be a problem and a distraction, so MAHA has some other chargers that might be more interesting in such situations. MAHA Powerex MH‑C800S and MAHA Powerex MH‑C801D which are AA and AAA NiMH/NiCD battery chargers with 8 independent channels for charging batteries and the only difference between the two is the charging current. The Powerex MH‑C800S has a Rapid Charging Mode with 1.0А and Soft Charging Mode with 0.5A per channel and the Powerex MH‑C801D is with 2.0A and 1.0A respectively and both these also have a Conditioning Mode intended to help revive batteries that are not performing optimally.


If you need similar chargers to the 8-channel Powerex models with lower charging current and similar simpler use and good quality you might also want to check out the chargers made by the Japanese company Tensai. They have the very nice 8-channel Tensai TI-800L, 12-channel Tensai TI-1200L and even 16-channel Tensai TI-1600L chargers for AA and AAA NiMH/NiCD batteries with independent channels for each battery. The charge rate per channel here is fixed at 0.5A for AA batteries and 0.25A for AAA, so higher capacity batteries might need more time to be charged, but in other hand if you don’t need very fast charging, but you need charging of a lot of batteries a single 16-channel charger can be quite useful for some. These chargers also have a Conditioning Mode for maintenance of batteries that are not giving their best.


Another good option are the LaCrosse Technology chargers such as the 4-channel chargers LaCrosse BC-700 (RS-700), LaCrosse BC-1000 (RS‑1000) and the many other names that these go rebranded under. The smaller LaCrosse RS-700 does have a bit more limited functionality giving you the ability to use only 200/500/700 mA per channel (independently set) and the better LaCrosse RS‑1000 supports 200/500/700/1000 mA per channel (up to 1500/1800 mA if charging only two batteries). Both of these chargers also support battery Refresh and Test modes aside from the standard Charge and Discharge modes and are good and more affordable option as compared to the MAHA MH‑C9000, though not as powerful and feature rich. The good thing is that these can probably be easily found, even if rebranded under another name in some countries, unlike the MAHA chargers that may be harder to be found in some places.


So far we have covered some of the best chargers for AA and AAA size rechargeable batteries, but what if you need a more universal charger that can charge pretty much all of the more common battery chemistries? For example both MAHA and Tensai are also making specialized chargers for 9V NiMH batteries (8.4V NiMH), but they are not as powerful as their models designed for the more common AA/AAA batteries, and the same goes for other battery types such as the C or D size NiMH batteries. If we want to add LiPo, LiIon or LiFe batteries or even Pb batteries along with the NiCD/NiMH models and have them in a single device we need to look elsewhere. A good and very popular choice is the SkyRC IMAX brand of chargers and one of their most popular model the IMAX B6AC, the model we are using this in our test setup for Lithium-based rechargeable batteries. The SkyRC IMAX B6AC is designed to charge NiMH and NiCD batteries in packs of multiple cells (it can still charge single cells), so it is probably not the best choice for such cells, but it can be used for 9V NiMHs (though it is limited to minimum 0.1A charging current). Regarding Li-xx batteries, you can charge 1 cell up to 6 cell batteries with a charge current between 0.1-5.0A (up to 50W) and discharge them with between 0.1-1.0A (up to 5W), there is also a built-in balancing functionality to make sure that all of the individual cells are charged properly. You can also charge PB batteries with a voltage between 2-20V. The B6AC charger can be powered by either AC input (100-240V) or DC input (11-18V), there is a B6 only version that does not include a built in adapter for AC input. What you should be very careful with these chargers is when buying to make sure they are genuine and really made by SkyRC and not a cheaper fake copy as they have a lot of copies, also have in mind that SkyRC has these chargers rebranded for some companies such as Team Orion for example. SkyRC also makes more advanced and powerful models that are based around the base functionality of the B6, but even a B6AC should be enough for most. If you however use LiPo batteries with more than 6 cells for example or even 3S-4S batteries with higher capacities you might want to look for more powerful models. There are of course a lot of other Li-xx chargers out there that are more powerful or offer extra functionality, but the B6AC should be more than Ok for most of you that need to have a good charger and don’t want to go doing things like advanced testing batteries for example.


The 1.2V AAA 950 mAh Powerex Imedion Rechargeable NiMH batteries are rechargeable batteries of the LSD type (Low Self Discharge) that are rated to retain up to 85% of their charge after 1 year of storage, unlike traditional NiMH batteries that will probably be completely discharged when stored for such a long period of time. The initial discharge capacity we got from these batteries was between 706 and 714 mAh with a low discharge current. Powerex is a brand of Maha Energy Corporation and is a well known brand among professional photographers for good quality batteries that are usually rated among the best and the same goes about the range of battery chargers that the company also makes. In fact we are using a MAHA Powerex C-9000 WizardOne Charger Analyzer as a part of our battery testing setup as we consider this to be one of the best AA/AAA battery chargers out there, so we do have very high expectations from these batteries.


We have started the test of the 1.2V AAA 950 mAh Powerex Imedion Rechargeable NiMH batteries as we normally do with a low constant current discharge rate of 0.1A and the result we got was 1062 mAh, or with a bit more than 100 mAh than the rated capacity. The great performance continues even after increasing the load all the way up to 1.0A where we still get 800 mAh as a useable capacity. As we expected the 1.2V AAA 950 mAh Powerex Imedion Rechargeable NiMH batteries do perform great by providing higher capacity than they are rated at and they manage to handle well in both low and high load applications.

The performance of the 1.2V AAA 950 mAh Powerex Imedion Rechargeable NiMH Batteries in our tests:

– 1062 mAh at 0.1A load
– 988 mAh at 0.2A load
– 877 mAh at 0.5A load
– 800 mAh at 1.0A load

– 1.325 Wh at 0.1A load
– 1.222 Wh at 0.2A load
– 1.057 Wh at 0.5A load
– 0.910 Wh at 1.0A load