This is the best charger I've found for charging C and D batteries (which I use for electric candles LED lights). It's big and a little clunky, but works very well. Much better than those chargers with the sliders"¦ I also have a Panasonic charger, which is more convenient for AA and AAA batteries, but sometimes this gets pressed into service as well, if I have a lot of batteries to charge"¦ it works fine. You have to push the button that says "Soft" after you insert the first battery, in order to engage the soft charging feature. That's weird, but you get used to it.

Prior to purchasing this, I was using an Energizer charger that has 4 slots and can do a timed charge on two pairs of AAA, AA, C, D batteries, or a single 9V battery in place of either of the pairs. After purchasing a new Roomba robot vaccuum, I grew tired of coming home to find it had entered a room it should not have been in. The Energizer C batteries that powered my virtual walls were being fully drained about every 3 weeks.

After a few charge/discharge cycles, I decided to get a better charger with better batteries. I ended up purchasing some ULSD (Ultra Low Self Discharge) 4500 mAh C batteries along with this charger, as I read that timed chargers don't do large capacity batteries justice. I still have yet to charge the ULSD batteries, which says more for the batteries than the charger, but you need a better charger once those batteries do get drained.

However, I have noticed substantially more life in my AA and AAA rechargeable Energizer batteries after doing a conditioning cycle on them. Prior to getting this charger, my AA powered GPS lasted me almost two full days of skiing. After a conditioning cycle (and using this recharger since), the same batteries consistently last about three days!

The only reason this did not get five stars from me is that running a conditioning cycle is unintuitive, and I feel that "soft charging" should be the default mode (it is the only mode I have used thus far). In my experience (and only using the soft/slow charging mode), I have not noticed the charger heating up to unsafe temperatures, as some other reviewers mentioned.

I purchased this product back in June of 2011 and was very happy with it despite the 8th slot not functioning correctly. I called MAHA customer service and with a simple, quick phone call and email I was sent a new unit(returned the first).

Now that it's been over two years of massive use from slow charging and conditioning, my Tenergy batteries still operate with peak performance. I spent a little extra for the Tenergy Premium batteries and am very glad I did.

Just a quick word of advice, always 'slow charge' every time if possible, just to maximize performance and health of your batteries. Likewise,please do not underestimate the 'conditioning' option that this unit has for your batteries. For my usage I decided to do this monthly for my D,AA and AAA batteries. Only annually for my C batteries that are rarely used. The button combination to do both of these features is by pressing the 'Soft' charge button then the 'Condition' button within a few seconds upon your placing the first battery in the unit.

So my experience has been great even with my brief customer service issue.

I wish it had some analysis reading for mAh state at the start of the charge and at the completion of the charge. That way no one needs to purchase a battery analyzer to verify the mAh charge being held by their rechargeable batteries. Oh well, it does great nonetheless.

So far using this charger to recharge a couple of my D cells have been proven good. Since the https://www.amazon.com/Powerex-MH-C9000-WizardOne-Charger-Analyzer-Batteries/dp/B003DIGKOG/ will only charge the cells up to 40% of capacity (4,000mAh) this charger eliminates that problem and if i need to charge more than 2 C or D cells at a time i can do this easily without much hassle. While using the C9000 is pretty good eventually since using adapters in order to charge D cells using the C9000 the internal resistance check will be too high for the cells to recharge in, so this charger will work better in that fashion. It also allows you to charge AA or AAA cells. So this is great if you need to charge multiple cells and those 4 cell smart chargers isn't enough. With the growing number of batteries i use and being able to have a set of cells on hand ready to go all at once this charger will do it just fine, especially if you have 8 cell devices. I do have a 6 cell unit so being able to charge them all in one unit now makes it easier. Otherwise i'll have to use two of the https://www.amazon.com/Panasonic-K-KJ17MCA4BA-Individual-Rechargeable-Batteries/dp/B00JHKSMJU which is fine, but additional slots are always better.

Now for the negatives with this unit. While it'll condition (or refresh) the cells you can't really tell if the cells are holding capacity or their voltage is not too low like with the C9000 charger. There's really no other info other than what it's showing with the battery life bar which i think there was more than enough space to get more info such as time, voltage, how much accumulate capacity and the charge rate. Another issue with this charger is you can only choose the soft (700mA charge rate) or the default rapid (about 2A charge rate). According to sources, the AAA cells will charge at 700mA (rapid) and 350mA (soft). Real world charge rate may be lower. However, as my understanding at the soft charge rate, the cells may terminate too late. The rapid option may be too much, perhaps better but without Eneloops AAA's i can't test this out. However i never charge above 500mA on AAA cells and 700mA with AA cells due to heat accumulation. The biggest problem here is if you have to charge D cells and some AA/AAA cells, having the charger on rapid may pose a problem.

Here is a breakdown of what the best charging option for each cell..

D Cells (higher than 8,000mA) - Rapid/default
C Cells - Rapid or Soft (Rapid for higher capacity C cells is ideal)
AA Cells - Soft only (May be a bit too high for some cells and may cause premature wear)
AAA Cells - Rapid (700mA) or Soft (350mA) Only recommended with high quality batteries such as Eneloops.

Choosing the soft feature may cause the Eneloops to miss termination (it is unclear if cells are partially charged).
Choosing the rapid/default feature may cause premature wear in Eneloops (depending if they get too hot).

I don't have any white AAA Eneloops to test this with so test at your own risk. I do not believe the cells should exceed 110F during charging (i prefer 100F) any higher may reduce the life of the cell. May or may not impede performance. This is especially true for lower end batteries such as AAA EBL and they have not exceeded this temp using the MH-C9000 charger even at 500mA (on partially charged cells). I have not tested this charger with AAA or AA cells so i can't say for sure whether this charger is safe for these cells. It may be ok for Eneloops as some people will use them but i prefer using the MH-C9000 for those cells as i primarily bought this charger for C and D cells.

I also forgot to mention that the power adapter box, gets pretty hot, so keeping this charger in a cool place is ideal, maybe place a fan in the area to help remove some of the heat from this adapter.

I've had this charger for about 3 weeks. Thus far, I've charged 2 sets of 8 Powerex 2700 mAh AA batteries and 1 set of 8 Energizer 2300 mAh AA batteries. I've only worked with it in the standard charging mode. It has performed flawlessly so far. That's not much time or very many chargings, but at 3 weeks it is performing as it should. The charger's done a great job (being new at this point) of fully charging the batteries, unlike an old 15-minute charger I previously used. In a few months I'll likely post again with how it's doing. So far, it's proving to be quite a descent charger for what I need. Having read about the fires a couple of folks have encountered with this unit, I was leery of getting it, but after reading various responses to those fires, and after having researched that issue online, along with all the very positive feedback, plus learning the pros and cons of the various chargers and battery types out there now, I decided to give this unit a try and see how well it would perform. At 3 weeks, I'm quite happy and satisfied with it.

Update on 12-15-2015:
Charger is still working great after 3 years.

Summary of important info from instructions page that comes with charger (maybe of use to someone):

* Only use NiMH or NiCD batteries.
* Has 3 charging modes: Rapid Charging mode, Soft Charging mode, & Conditioning mode
* Charges from 1 to 8 batteries at one time (any charging mode)
* When in Rapid Charge mode, ONLY use AA / C / D batteries of 2000mAh (or higher), or AAA batteries of 700mAh (or higher) - takes 1 hour if batteries are empty.
* When in Soft Charging mode, can charge any type of battery size, but AA / C / D batteries less than 2000mAh, or AAA batteries less than 700mAh, will ONLY work in this mode. (I accidentally tried a 1000mAh AA in Rapid Charge mode once and it starting sizzling in a weird way. I immediately took it out - no damage, fortunately, to battery or charger.)
* Has independent charging slots.
* Charge Times: AA / AAA: 1 Hour (Rapid), 2 Hour (Soft)
C: 1 to 3 Hour (Rapid), 2 to 6 Hour (Soft)
D: 1 to 5 Hour (Rapid), 5 to 10 Hour (Soft)

Update on 4-17-2019:
Charger is still working great after 7 years. Due to necessity, have recently purchased a second one in order to charge enough batteries on short notice. I charge mainly AA batteries (PowerEx and Energizer, some of these are 7-10 years old).