When I was a Crew Chief for a large convention center that often ran 30+ wireless microphones, keeping a supply of reliable rechargeable batteries on hand wasn't even a question. We went with these Ansmann 2850 mah AA, and they came through the show, usually with plenty of juice to spare. When I started using them with my touring band, I immediately discovered what a great value they are. By about the fifth time I charged them, they'd already paid for themselves. Today I use them in every battery-powered device I own, even around the house!
I use these batteries in my wireless mic units at church. They are good for at least 12 hours of run-time in our Sennheiser EW series. Tried rechargeables in the past but these definitely are the real deal. I'd recommend them for any church that wants to save money on batteries
A Great substitute for expensive OEM rechargeables
This review and subsequent numbers are based on use in the Shure PSM900 wireless receiver unit. I bought these batteries and charger because I did not feel comfortable with Shure's estimated usage of 4-6 hours. That is cutting it too close for me in a paying gig situation so I decided to give these rechargeables a test run.
Once charged the batteries seem to consistently last between 10:45 hours and 11:15 hours. This was with both sets in different configurations so that all batteries were eventually used together.
The amber light on the PSM900 receiver would typically come on when there was about 30 minutes left and the red light would come on with less than 15 minutes. Once the red light went on, the wireless lost power within 5 minutes or so. Turning off the unit and letting it sit for a couple hours restored the green light and power for about an hour. I did not try this but once.
Overall, these are a fantastic substitute for the Shure lithium battery which promises roughly the same amount of time at 5x the cost when you figure the cost of battery and charger.
Lasts much longer than I thought!
I had difficulties with them at first (mostly the chargers fault) but once they were broken in the did a whole lot better than I expected. Went as long as 12 hours and a few minutes on my Zoom H6.
The bars would go all the way down to one bar and then level off and run for a very long time after that. So there is a drop-off at first then it settles at the one bar level and then it runs a very long time after that.
So I you use these with a Zoom H6, do not worry about it quickly going down to one bar. It will still have a lot of time after that.
It is the way the discharge curve is with these batteries.
I have used other batteries in the past and have not found anything that measures up to the 2850 AKKU's. They seem to keep their charges for the services that I have in my church and that is usually 3 services on Sunday and 1 on Friday. I am happy to say they are great.
These are quite capable at 2850 mAH compared to "precharged" supermarket NiMH batteries at 2300 mAH, BUT the self discharge rate is much higher!!! According to my fancy ZTS battery tester the precharged batteries fresh out of the package (no doubt charged months ago in China) are still at 80% capacity where my Ansmann batteries lose about 10% of their charge a day. So if you tend to charge before a gig, then the Ansmann batteries are the way to go. If you tend to charge after a gig (my habit to clean everything up) then you are better off with low leakage NiMH batteries (sold in retail as "precharged").