The Energizer Recharge Extreme AA 2300mAh managed consistent performance in my tests, delivering more capacity than the rated value. There’s a lack of information on exactly how many charge cycles these batteries can take and how much charge they retain. At this price, though, there are higher capacity batteries available.
- Consistent performance
- High capacity in my tests
- Little longevity information
TypeThese are NiMH AA rechargeable batteries.
CyclesEnergizer doesn’t quote an exact figure, but these batteries are rated to last for hundreds of charges.
The Energizer Recharge Power Plus AA 2300mAh are the highest-capacity batteries in this range.
They consistently performed above their rated capacity, but it’s hard to get detailed information on longevity or charge holding capability. There are alternatives that may be better suited to you.
Design and Features
- Can be cycled hundreds of times
- Holds charge for up to 12 months
The Energizer Recharge Extreme AA 2300mAh come pre-charged, which shows that they’re low self-discharge batteries. As with the Energizer Recharge Power Plus AA 2000mAh batteries, Energizer doesn’t quote how much charge these batteries maintain after 12 months, just that they keep their charge.
Likewise, Energizer doesn’t quote how many charge cycles these batteries will last for, just that they have a total life of up to five years under typical use patterns, and that they can be charged hundreds of times.
The competition, such as the Duracell Rechargeable AA, are much clearer about charge cycles and the total capacity remaining.
- Very stable performance
- Performs better than capacity would suggest
I use an Ansmann Energy XC3000 to test rechargeable batteries. First, I measured the starting voltage of the Energizer Recharge Extreme AA 2300mAh, which should be at least 1.2V: I measured the batteries at a decent 1.38V. That’s just a starting voltage, mind: as the batteries are drained, voltage drops.
Next, I measured the capacity of the batteries, running a high-drain test of 600mA (+/-20%). I found that the batteries returned a capacity of 2494mAh, which is higher than the rated capacity.
To see if there are any signs of early fade, I also cycle batteries 50 times, taking measurements every 10 cycles. From the graph below, you can see that performance is stable, with only small fluctuations in readings.
Should you buy it?
If you want a solid set of batteries with decent capacity, then these are a good choice.
If you need more power, there are better choices, and there are batteries guaranteed to last for more charges.
The Energizer Recharge Extreme AA 2300mAh are a reliable and consistent-performing set of batteries, but I’d like the company to be more upfront about the number of cycles they can take and the average remaining battery life after 12 months.
Without this information, I can say that the Duracell Rechargeable AA have more capacity, and the Eneloop AA are rated to last for 2100 cycles and still maintain charge after ten years.
How we test
Unlike other sites, we test every rechargeable battery we review thoroughly over an extended period of time. We use standard tests to compare features properly. We’ll always tell you what we find. We never, ever, accept money to review a product.
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We use an Ansmann Energy XC 3000 to drain batteries, so that we can test capacity in mAh. After the first run, we charge and discharge 50 times, measuring the capacity every ten runs.
We measure the initial voltage of the batteries, checking that the starting voltage is at least 1.2V.