Sony Cycle Energy 2000 mAh Pre-Charged AA Rechargeable Batteries

 (36 customer reviews)

The Sony Cycle Energy 2000 mAh Pre-Charged AA Rechargeable Batteries are low-self-discharge NiMH type, similar to the more well-known SANYO eneloop. Even their marketing claims sounded almost identical, such as:
- 'Stays 85% charged after 1 year of storage'
- 'Recharge up to 1000 times' (2nd-gen eneloop cells actually claim to achieve 1500 cycles)
- 'Battery Capacity: 2000 mAh'

Naturally, this leads to speculation that SONY Cycle Energy is just Sanyo eneloop under a different wrapper. But apparently it is not the case, based on the following observations:

1. There are minor differences in shapes of positive and negative terminals between those two...Read more

I am an electrical engineer, and I have tested many, many batteries. The Sony CycleEnery batteries are the best batteries in the world. No other battery has performed as well for me. I highly recommend this battery above all others.

There are two things that make the Sony CycleEnery battery perform so well:

First, if you weigh the Sony battery on a scale, you will find that they are several grams heavier than any of the other brands. This means that there is more material inside, which yields a higher battery life span.

Second, the voltage curve of this battery stays above 1.2 Volts throughout the majority of its life span. The reason this is important is that most electronic devices, such as digital cameras, stop working once the voltage goes below 1.1 Volts. Normal NiMH batteries can have extremely high mAh ratings of 2500 or more -- but you can't actually make use of all those mAh's because the voltage drops below 1.1V relatively early -- this...Read more

I bought two sets of AA and one AAA of these Sony Cycle Energy batteries from a large NY-based and internet camera store during an 8 USD/AA 4-pack deal was posted on slickdeals a couple of weeks ago and I wanted to relay my experience. (Though I do buy most everything else at Amazon!)

All of the batteries were made in China as per prior posts. They all came out of the package with decent voltage (1.3v? I don't recall exactly) but at maybe 50% of the rated charge of 2000 mAH. I personally don't much care since I was going to charge before using anyway. I had encountered a significant variation with 4 of the 8 AA batteries -- 3 from one pack and one from the other pack.

I use the La Crosse BC-700. I did a simple charge of all of the batteries first. That did not bring the charge up near the rated level. On the first 4, I did a single full discharge-charge cycle and they went up as high as almost 2400mAH! Great! The other 4 did not fare as well. A discharge-charge...Read more