Average Customer Review:
With rechargeable batteries, you have to make a tradeoff between power and service life. High-power batteries, which can store over 2,400 mAh of charge, last longer both in your devices and on the shelf. However, they can't be discharged and recharged as many times as lower-powered batteries that hold between 1,000 and 2,000 mAh. So the best battery for you is one that delivers as much power as you need, but no more.
The Energizer Recharge Universal (Est. $18 for 8 AA batteries) is on the low-powered end, with a claimed capacity of 1,500 mAh for the AA battery. However, testers at TheWirecutter.com found that this battery actually delivers 1,888 mAh on average – more than the popular Panasonic Eneloop Rechargeable (Est. $21 for 8 AA batteries), which has a claimed capacity of 2,000 mAh. This extra power translated to better performance in an endurance test, in which a soldered-together pack of Recharge Universal batteries kept a remote-controlled car running around its track for roughly half a minute longer than the Eneloops. And the Recharge Universal batteries continued to deliver the same level of power even after four dozen charge cycles – the equivalent of about a year of heavy use.
The Recharge Universal batteries have a few extra perks, too. Unlike many rechargeable batteries, they're available at several major retail chains, so you don't have to order them online. Also, 4% of the material in them is made from recycled batteries – a bonus for the environmentally minded. Energizer claims that these batteries can be recharged up to 1,000 times – a lifespan of up to five years, with typical use – and can hold their charge for up to 12 months in storage. Reviewers at Amazon.com generally confirm that these batteries last a long time and hold their charge well. However, some note that these "pre-charged" batteries aren't always fully charged out of the package.
The biggest drawback of the Recharge Universal batteries is their relatively low capacity, which makes them too feeble for high-drain devices, such as camera flashes. If you need more juice, a good bet is the Panasonic Eneloop Pro (Est. $20 for 4 AA batteries), which has an unusually high capacity of 2,550 mAh. Electronics enthusiast Stefan Vorkoetter, writing at his site, StefanV.com, has conducted extensive comparison tests of rechargeable batteries and confirms that the Eneloop Pro delivers more charge than any other rechargeable battery in his test, both fresh out of the package and after seven weeks on the shelf. The Eneloop Pro also scores near the top in a professional comparison test, lasting nearly two hours under a fixed load of 10 ohms. Owners at Amazon.com also say these batteries perform better than any other brand in high-drain devices. Several photographers say their flash bulbs recharge noticeably faster when they're using Eneloop Pro batteries.
However, this high-powered battery has its downsides. Not only is the Eneloop Pro one of the priciest rechargeable batteries on the market, it also doesn't have as long a lifespan as other options. Panasonic claims that these batteries can be recharged up to 500 times, but professional tests say otherwise. In one test, the batteries are still going strong after 60 recharges, but they fail before making it to 100. Another downside of the AA Eneloop Pro is that their dimensions appear to vary slightly from those of a standard AA battery, and we see some reports of the batteries not fitting in some devices.
If you're looking for the battery with the longest possible service life, sources point to the Eneloop Rechargeable as your best choice. According to Panasonic, the latest generation of Eneloops can be recharged up to 2,100 times. No one has ever tested this claim fully, but the batteries make it handily through 200 charging cycles in one professional test with no discernible drop in charge capacity. Also, some users at Amazon say their batteries are still going strong after years of regular use.
The Eneloop Rechargeable also boasts a very long shelf life. Panasonic claims that Eneloops retain 70 percent of their charge after ten years in storage. While no one has tested the batteries over this long a period, TheWirecutter.com found that the Eneloop lost only 17.9 percent of its charge after nine months on the shelf. The downside of the Eneloop is its relatively low power. Although its claimed capacity is 2,000 mAh, TheWirecutter.com found that it actually delivers only 1,849 mAh on average – less than the Energizer Recharge Universal, and far less than the Eneloop Pro.
The bottom line is that if you need AA batteries with the highest possible capacity, and you're willing to pay for them, the Eneloop Pro is a good bet. On the other hand, if you don't need that much power and you want your batteries to serve you for many years, the Eneloop Rechargeable is the best choice. And if you want a middle ground, combining decent power with a decent service life, stick with the Energizer Recharge Universal.
Most tests of rechargeable batteries focus specifically on AA batteries. However, TheWirecutter.com recently added AAA rechargeable batteries to its test and made a surprising discovery: they all perform about the same. All four brands they tried had about the same initial capacity and held up well after four dozen cycles of charging and discharging. They also did equally well powering up a headlamp attached to a melon, petering out after six hours.
TheWirecutter.com concluded that any reliable brand of AAA batteries will perform adequately, so it's best to choose based on price. In most case, this means that the AmazonBasics Rechargeable (Est. $10 for 8 AAA) is the best choice. Users at Amazon.com agree, awarding these batteries 4.5 stars out of 5 overall in more than 3,200 reviews. They say the batteries last a long time, retain their charge well in storage, and hold up well over the long term. However, the Eneloop Rechargeable, Energizer Recharge Universal, and Duracell Rechargeable (Est. $11 for 4 AAA) should also serve your needs just fine if you manage to find a good deal on them.
Most rechargeable batteries are available only in AA and AAA sizes. However, Energizer offers the Energizer Recharge (Est. $11 for 2 D batteries) in C, D, and 9-volt sizes. Energizer claims these can be recharged "hundreds of times," but it makes no specific claims about their overall lifespan or shelf life. Also, like the Energizer Recharge Universal, these batteries are on the low end for overall power. Many users at Amazon.com warn that the C and D batteries have a capacity of only 2,500 mAh, which means they don't run nearly as long as similarly sized alkaline batteries.
If you want a C, D, or 9-volt rechargeable battery with more staying power, the only decent option we've found is the Powerex Precharged (Est. $30 for 2 D batteries). These batteries have replaced the well-rated Powerex Imedion, which energy expert Michael Bluejay names as his favorite rechargeable battery. The Powerex Precharged line has even more power than the old Imedion: 5,000 mAh for a C battery and 10,000 mAh for a D. It also offers a choice of 8.4-volt and 9.6-volt batteries for use in 9-volt devices.
Owners at Amazon.com agree that Powerex Precharged batteries last a long time, even in high-drain devices. However, all this power comes with a very high price tag. Even though the Powerex Precharged AA (Est. $13 for four AA batteries) is the overall top performer in tests at TheWirecutter.com, the editors don't recommend it because it's so expensive. The choice is yours: pay extra for the long-lived Powerex Precharged, or spend less for the Energizer Recharge and be prepared to recharge it more frequently.