The Longest Lasting Rechargeable AA Batteries

Sanyo’s Eneloop batteries have had an edge over other rechargeable AAs since they were released in 2005. Basically, Eneloops could retain their charge longer than other rechargeables, including other low self-discharge AAs. Eneloops can hold 85% of their charge for one year, and 75% after three years.

Now, Sanyo has released a new version of the Eneloop, called the Eneloop Pro (in Japan) or Sanyo XX Battery Powered By Eneloop (in the US and Europe). The Eneloop Pro battery has a capacity of 2500 mAh — which is 500 mAh more than the regular Eneloop. In informal tests, Eneloop Pro retained 2035 mAh of capacity after 7 weeks of storage, which was higher than any other NiMH battery (both regular or low-self discharge), making it the longest lasting rechargeable AA battery. The only other battery to come close was the Energizer Recharge, which retained 1859 mAh after seven weeks of storage.

Eneloop Pros are available at Amazon. You can also buy the Eneloop Pros with a charger included.

Sanyo hasn’t released an AAA version of Eneloop Pro.

25 thoughts on “The Longest Lasting Rechargeable AA Batteries”

  1. Odd to read this post that states these batteries COULD last longer than others.
    Could, maybe, possibly, if, might, but, or….these words will prevent a potential
    buyer from buying something, like myself….

  2. Be careful about buying any Eneloop Pro AA rechargeable battery. Even they are similar, but they have some clear differences. Nowadays, there’s to many fake Eneloop pro battery. The only genuine Panasonic Eneloop Pro has been packed and labeled with 2550 mAh and pre-charged on it’s packing. The fake ones are packed and labeled with 2500 mAh and pre-charged rechargeable on their packing.

    1. Actually this may be the case for some batteries, however there are battery brands that are made in the same plant as the Eneloop Pro batteries. I purchase the Ikea Ladda rechargeable batteries and have found out that they were manufactured in the same plant and to the same standard that the Eneloop batteries are produced. They also cost me much less than the Eneloop batteries ($8.00 for Ladda vs $20.00 for Eneloops).

  3. This article that you have written here is really very informative and helped me in doing a project efficiently. I am waiting for some new posts from your blog. I will follow your blog for the new updates always. I am into Scientific Team where we developed these things from the very beginning but I have get this information really helpful for my new project.

  4. BTW I was thinking that these batteries don;t work long. I was trying to make some new product like this but then I have found something like this in my nearby market. These batteries are really very nice.

  5. My wife goes through triple A batteries like you wouldn’t believe, I finally mentioned to her that they make rechargeable batteries… can you believe it she didnt even know that certain batteries were made to be recharged. we are looking to buy some rechargeable batteries now which is how we found this article great information across the whole site, thanks.

  6. I think it’s actually a really smart idea to invest in long lasting batteries as opposed to recycling through those cheap ones that you get at a huge discount. The idea behind it is convenience and cost. It’s surely much more convenient to put in a battery and be able to forget about it for months if not longer.

    As far as cost goes, if you think about the times where you make a trip to the store to buy replacement batteries, there’s fuel costs, and the possibility of buying stuff you didn’t need at the store. When looked at as a whole, long lasting batteries actually make life better and don’t really cost you more.

    Efficienist @ The Efficienist

  7. When evaluating anything, it is the right thing to do to list the attributes, and then evaluate each one. The problem that may arise is when the evaluator places much more weight (or importance) to a specific attribute, which may or may not be as important to readers. The evaluator in this product seems overly hung up on the “low self-discharge” attribute of the battery. Great, you can charge a battery, throw it in a drawer and one year hence, it will still have 90% of the charge!


    That attribute does not seem to be very useful, because people do not typically charge batteries, and store them for long periods. other attributes such as:
    * Power stored: how long before the battery drains.
    * Number of recharging cycles it allows before the battery really can’t hold the charge
    * Price

    Those would be more important

    1. P. Ramos,

      Your methodology would be appropriate for an article entitled “An Evaluation Of AA Batteries, Based on Price, Charging Cycles, and Power”. However, the title of this article is “The Longest Lasting Rechargeable AA Battery Of 2012”.

      Long lasting batteries are useful in devices like flashlights, remote controls and game controllers. Most don’t enjoy having to recharge their batteries every month or so — they become disappointed when they pick up the device, and find the batteries dead. Thus, Eneloop low-discharge batteries are significant step-up from conventional NiMH batteries.


    2. If Justin’s review had included just a % of charge retained, you might have a minor point. Since he provided the absolute capacity retained in mAh (measured, not Sanyo’s spec), then you do know the “power stored.”

      I doubt that anyone is going to take the time to test manufacturers’ specs on total cycles–to test a single battery model would take weeks. Would it be nice to know? Sure! I doubt we’ll ever see that test of all battery makes and sizes, though.

      As for price: That changes daily, so what would be the point of a snapshot comparison that would be obsolete the next day? This is what Google Shopping searches are for, after all.

      So this is probably the best you’re going to get. Welcome to the world of caveat emptor.

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