Powerex Precharged Rechargeable AAA NiMH Batteries (1.2V, 1000mAh, Low Self-Discharge) - 4-Pack

I've owned several sets of Powerex batteries and they have always performed well. This review is specifically for the Powerex D cell 10 Ah variety. I bought these in 2016 and as of 2023, they are still working well. Capacity as reported from my Opus charger is still around 9970 mAh, which I think is great. Although I have them 8 years, I probably only charge them about 4 times a year, so they haven't been cycled too many times. When I bought these, they cost about 60% of what they do now. Given that in the devices I use these in that I would have gone through about 4 sets of regular D cells per year, the breakeven for me came after 2 years, so despite their high cost, they have still saved me quite a bit of money. I was kind of shocked to see the price of them now, so that would be the only negative, but I guess you get what you pay for. They are true D cells with the corresponding higher capacity, not C cells that have been put in a D cell case. If you don't need the kind of capacity these provide, you can save some money buy buying the lower capacity cells, but if you do need the higher capacity, these work very well.

I have been using these with our Shure wireless microphones, and they perform consistently for a long time instead of slowly fading.

I still have AA 2700 and 2800 mah batteries that are over 10 years old that still work in low discharge. Yes they are pricey but much better value than the cheaper batteries that you can find here. I measured the capacity using the MH-C9000Pro charger/analyzer/conditioner and they all came up to over 1000mah after 3 charge and discharge cycles. I've tested a few different brands of AA and AAA(energizer, tenergy, etc) and they all come up short in the tests.I've not tested capacity of C or D batteries yet because my unit is unable to test them natively but I did buy some adapters that will connect to this unit and able to charge the 10,000mah D batteries. I use some "fake" C size batteries that really only have about 1500mah of capacity for an inflatable bed that I use a few times a year. The batteries are just enough to inflate so it's not like I need HI capacity C batteries for anything.I am curious though, I would love to put to the test the real C and D batteries, but I rarely use them, so the cost is too expensive for me to buy these to use twice a year. So if any of you would like to send me 1 or more C or D batteries to do an engineering analysis on, I would be more than happy to discover which C/D batteries have the highest capacity. I can also test 6 months later, how much capacity is left. I will be posting the actual picture showing total capacity for each battery after the cycle. I charge at .25C and discharge at .5C. Meaning it takes 4 hours to charge and 2 hours to discharge.I used this device to measure capacity and break the batteries in.https://www.amazon.com/Powerex-MH-C9000PRO-Professional-Charger-Analyzer/dp/B08DJDQ4Y8/ref=sr_1_2?dchild=1&keywords=powerex+charger&qid=1601666623&refinements=p_89%3APowerex&rnid=2528832011&sr=8-2

The media could not be loaded. these are the batteries that you can depend on, i purchased several powerex batteries and i used them to power my eton field radio and they are very reliable, doesn't drain fast and if I may suggest use the powerex mh c808m charger designed to charge d cells, for quite sometime these d rechargeable batteries were out of stock finally amazon replenish their stocks and iwas able to order several packs of these batteries, low self discharge rate is added feature since the radio that I am using them with consumes a lot of batteries, somewhat pricey but I believe they are worth the investment in the long run, a much better alternative for alkaline batteries which are quite expensive and sometimes, they leak which will damage your equipment.these batteries are quite hard to find and different stores do sell them but with added costs, sometimes you will be charged with the shipping, almost one third of the cost of batteries. amazon ships it for free most of the time. I do hope that amzon will re-stock the mh c808m and the powerex 100 minute cool chargers,grateful to powerex and amazon for leveling the playing field!

These are great AA rechargeable batteries. Tested the capacity by draining the battery with a 1.2 volt incandescent bulb @ 250 mA and recharging the battery with a XTAR VC4 charger @ 1A. The battery tested full at 2572 mAh. This was very close to the 2600 maximum mAh rating.After two months of unused storage, I removed two of the batteries for testing. I recharged both as above and the batteries charged at 411 and 412 mAh. This is about a 16% loss. This amount of drain should only happen after one year. Lowering my rating by one star.

Works on my (ancient) Empi Tens unit, although it's a bit thick.Since you can't get the actual Empi batteries anymore, these were about the only ones that I came across that had the right voltage and were close enough in depth to actually work in the Tens case. And, they do work. I did have to move the little fabric battery pull in the tens battery compartment out of the way, but after doing that, they fit without a problem. And, the PowerEx charger is much better than the original EMPI tens battery charger, so I expect these batteries will hold up better than the Empi ones did over time.

I'm very disappointed in the quality of these batteries. I bought them thinking they must be worthwhile because they're the same brand as the charger I bought. But either these batteries are bad or the charger doesn't work right. The result is still the same, that they don't charge fully or discharge too quickly. Very frustrated here. I wonder if the AA's will be the same. So much money spent.