Do Rechargeable Lithium-Ion AA Batteries Exist?


Do rechargeable lithium-ion batteries exist in standard sizes like AA, AAA, C or D?

Yes, they are finally available. A company called Kentli has released AA and AAA rechargeable lithium polymer batteries that output 1.5 volts.

Kentli batteries are available on Amazon here.


Lithium-ion batteries normally operate 3.7V per cell — but Kentli put circuitry inside the cells to reduce the voltage to 1.5 volts. The company claims that the batteries have a capacity of 2800aH which matches Eneloop Pro (the NiMH batteries with the highest capacity).

Additionally, Kentli batteries are lighter than Eneloop Pro. However, they are more expensive. A four pack of Eneloop Pros costs about $17, whereas a 4 pack of Kentli cells costs about $40.

Sanyo XX "Powered By Eneloop"

Other Lithium-Ion Rechargeables


There are also some lithium-ion rechargeable batteries made for high-performance flashlights and cameras, in these sizes: 18650 and CR123.

A single 18650 battery can replace two CR123A batteries, although at a lower voltage (but much higher amperage). However, the 18650 is a wider cell and will not fit into a flashlight that is designed strictly for the narrower CR123As. Most modern tactical LED lights are designed to use a single 18650 or two CR123As, but it’s best to check before buying. See our article on The Best 18650 Batteries for more information.

There are also numerous other types of lithium-ion batteries made for specific laptops and other electronics gadgets. There is currently no standard size for these lithium-ion cells.

Comments 34

  1. Conundrum

    Hi, yes I think they have an internal voltage divider so the terminal voltage is between 1.3 (fully discharged, cut off soon!!) and 2.05 (fully charged, basically half of 4.1V)
    this actually drops right down shortly after to the lithium working voltage of 3.7V which corresponds to a terminal output of 1.85V.

    the catch is that they as OP mentioned need a special charger that connects to the normally inaccessible outer ring, inside they have a barrier circuit which prevents the lithium voltage being accessible.
    The chip essentially does three functions namely voltage conversion, PCM and charging/lockout.
    It also has a unique code which prohibits charging if used on another brand charger for safety reasons.

  2. Pingback: Ricaricabili Kentli da 1,5 in un flash SB710?

  3. Prateekk

    + Charger Combo (Camera) I purchased two sets of these beieartts on different days from the seller CREE Flashlight. The first set I received was defective the included battery charger LED turned went out after about a minute of being plugged in. I wasn’t sure if the beieartts were still being charged, so I pulled them off the charger and measured the voltage with my digital multi-meter. I plugged them back into the charger for an hour, and took another reading. One of the beieartts remained the exact same, and the other actually lost .02 volts. I spoke with Amazon about getting a replacement and was asked to send this set back while another was shipped to me. I decided that I would keep the original set until I had the opportunity to compare them to the replacements (fully charged, of course) and would select the two best beieartts from the set of four.I received the second set promptly (thanks, Amazon!) and put the beieartts in the charger. It worked! About 45 minutes later I had two beieartts charged to 4.16 volts (according to my DMM). I charged the original set of beieartts as well. One came off the charger at 4.17 volts and the other at 4.16 volts. This shows that these beieartts are at least consistent when charged.To test the beieartts’ capacity, I put one in my Zebralight SC600 flashlight. For those that don’t know, this flashlight is amazingly consistent with battery usage. Prior to purchasing these beieartts, I used several different AW protected 2900 MAH cells in the flashlight. On the 330 lumens high mode, I could consistently get just over three hours of use from the AW beieartts. Using the first of the new Ultrafire beieartts, I didn’t even break the two-hour mark before the flashlight dimmed to maybe 30% of the normal output.I repeated this test with each of the four Ultrafire beieartts. I didn’t get more than two hours from any of the four beieartts that I received. This was disappointing, considering that these beieartts were supposedly rated higher (3000 MAH) than my AW 2900 MAH beieartts.Given the faulty charger with the first set and the consistently poor performance from all four beieartts, I cannot recommend these. I will be returning all four beieartts and both chargers.

  4. Kevin

    We currently use NiMH in sealed packs of 4. The current draw of the unit is 1 – 2 amps and we are looking for a more reliable battery. The supplier has been using batteries without any marking. Over time we’ve gotten shipments which work very well and others which we get nothing but complaints from customers. we’re in a down cycle now which is why I’m looking for a more reliable battery and supplier. Because of the charging method used on these batteries is it possible to to put 4 of these into a sealed rechargeable pack? Has anyone figured out how to use the 6v (1.5v x 4) output and also be able to charge them at 3.7v ea as a pack? Is it even possible without incurring a high cost?

    1. E. F. Basham


      I’m in a very similar situation – 4 NiMH cells AA size, iffy vendor quality, looking for a high energy density lithium (Lipoly or LiFePO4) solution instead in the same volumetric size in NiMH. What I had seen were primary lithium (ie disposable) cells for cameras that were a fixed pack the size of 2xAAs as one piece, sold by Kodak & used in Olympus & other cameras/flashs. The pack had a positive on one side and negative on the opposing side, which would put the Lithium voltage at the same spring terminals for AA cells without terminals on the product battery case jumpers meant for 2 AAs.

      It would thus seem possible for applications of EVEN numbers of AA cells to use half as many lithium secondary (rechargeable) cells, potentially prismatic size packages, in the same space. I’m surprised nobody has created such a package, as the double-AA Li package was standardized on for several camera brands.

  5. Michael freed

    3.7 lipo batteries require a low voltage cut off to prevent deep discharge resulting in a destroyed cell,,can’t see any discussion about how these 1.5cells can be used in devices without this circuitry ,,am I missing something here?

  6. Lex Luthor

    I was searching batteries by voltage and I found some Li-ion rechargeable AAA batteries ( a brand I never heard of B4.) Said brand also have AA sized Li-ion for sale but no product reviews yet so I’m wary. …… I can find tons of 1.2v & 1.5v N cell batteries overseas but not any rechargeable li-ion lithium ones. Stateside the N size battery exists in Nimh and Nicd form only =(

  7. james braselton

    hi there you know i did not know the lithum ion aa batteries running at 3.7 volts at 350 mha capacity vs 1.5 volts thats about 2.5 times longer life cycle means it will run like a 1.5 volt 700 mha too 1,000 mha 1.5 volt battery life cycly

  8. james braselton

    hi there wow only 350 mha batterys aa i have seen aa rechargable aa batters useing 12 grams of water with 1,000 mha and the highest recharagable 3,500 mha batters 10 times high capacity then these batteries infact some recharabele batters are warped in a solar cell out put over 50 mha on aa recharging in sun light

  9. Irvinong

    Dear Sirs,

    Can anyone tell me why rechargeable AA/AAA batteries always come with voltage 1.2v and not 1.5v compared with same size normal batteries. Thank you


    1. web master

      While it is true that the average alkaline battery has an output of 1.5 volts when it is new, in reality, an alkaline’s lifecycle is such that it quickly drops from 1.5 to 1.0 volts before dying out. Because of this, the average output of an alkaline battery is the same as that of an NiMH rechargeable battery: about 1.2 volts. An alkaline battery really only outputs a 1.5 V voltage at the very beginning of its use. Soon after, it begins to decrease down to well below 1.2 V, bottoming out around 0.6 V.

      Most of the basic consumer electronics function normally using battery power with an output between 0.9 V and 1.5 V. However, unlike alkaline batteries, where the voltage drops quickly and gives you performance that’s well below 1.5 volts, NiMH rechargeable batteries, on the other hand, provide a steady stream of voltage from the beginning of its charge until the very end – about 1.25 V.

  10. JP White

    Time for an article update. Kentli hav released a 1.5v AA and AAA rechargeable lithium polymer battery.

    They overcome the recharge concerns by making the battery nipple not accept a charge at all, you buy a specially designed charger that charges using a ring contact and charges the battery at higher voltages than it outputs via the nipple.

    These cells have circuitry to reduce the voltage down to 1.5 volts and claim that the battery has a capacity of 2800ah as good as Eneloops Pros but lighter in weight.

    Biggest disadvantage is that they are expensive. For specialist applications they maybe a decent choice.

    It will be intersting to see if the price of these cells comes down and lithium ion technology progresses.

    1. Steve

      I think you will find that these Kentli 1.5v Lithium batteries are 2800mWH not 2800mAh. Not the same thing. They are rated at less than 1000mAh.

      1. Tim Greensgod

        These indicated in mWh because that is the standard unit for lithium ion capacity ratings. You can easily convert to mAh.

        mWh / V = mAh

        2800 mWh / 1.5 V = 1866.666 mAh

        The product appears to be very real. As far as I can tell, it’s the first rechargeable AA li-ion product on the market that correctly regulates its voltage to 1.5 V.

        Kentli’s marketing site
        Teardown of these Kentli AA lithium ion rechargeable batteries
        Some guy’s YouTube video review of the PM5 model
        Order directly from Shenzen

        I just placed an order. We’ll see how it goes.

  11. Jim

    I bought 1.5V Lithium AA batteries in May 2014: ‘Energizer Ultimate Lithium’. When brand new, they read 2V. There is no ‘additional ring’ for a different voltage. Is this new information, or did they just come onto the market? And why would they not be rechargeable? Why would they burn or explode when charged? My cordless tools all run on Li-Ion, and those batteries recharge very quickly. Seems to me if you don’t overcharge them, they shouldn’t explode.

  12. PatZ

    As a matter of fact there are 1.5V Lithium-ion battery, at the positive end there is an additional ring for 3.7V/4.2V charging and the center is 1.5V output.
    It is more expensive for sure but the matter is it does exist.

  13. Scarlet Liu

    Hello,this is Scarlet from XND technology Co., LTD. Is there anyone who needed purchasing the rechargeable Li-ion batteries? We can supply for you with compititive price. My Skype is : batterystar


    1. Chris

      I have a number of energizer advanced lithium batteries left over from my camera ,I tried charging them in a regular nimh charger it worked they charge to a higher voltage with the average being about 2.8V some didnt charge and became quite warm but not hot but at least 75% of them worked at least once

      1. Gil Heroux

        I accidentally charged some energizer advanced lithium batteries over night I was using in my tooth brush. I put them back in and they worked for a week. When I went to recharge them again, I noticed they were not rechargeable. I put them in the recharger for three hours and they worked for another week. I did this a third time, but when I tried the again, they were dead, dead, dead.

        I have not tried to do that again.

  14. Steve

    I think it would be great if there could be a consumer usable AA and AAA li ion battery version. I find no matter how well we manage our rechargeable batteries they always end up with battery memory.

  15. Anonymous

    Some people use a 14500 and a spacer for the (rough) equivalent of x2 AAs.

    Some people reqire their electronics to take x2 14500s in parallel instead of x2 AAs in series.

  16. dave

    This blog is incorrect. Rechargeable Lithium-Ion batteries do exist in AAA and AA sizes. They are VERY common, are named based on their dimensions which are (AAA) 10440, and (AA) 14500 cells.

    If the author of that book suggested otherwise, the book is a joke as this isn’t something one would have to be an engineer to know, NOBODY who knows modern day batteries does not realize they do come in AA and AAA sizes.

    Don’t get me wrong, I’m not suggesting they are interchangeable in devices meant for alkaline or NiMH/NiCd AA or AAA cells due to the difference in voltage, but they most certainly do exist and the author of the book seems to have created a work of fiction that is probably best avoided.

    1. web master

      Yes, the same size, but different voltage – so people should not use them as replacement AAs.

      1. 14500

        I personally use a 14500 as a AA replacement.
        I use ONLY ONE 14500, and an empty AA spacer (with a wire inside connecting the + and – terminal), to replace two AA batteries.

        Works fine on most of my gadgets that require an even number of AA batteries, and have them in series.

    2. Jeff

      Does nobody read?

      “Lithium-ion batteries normally operate 3.7V per cell — but Kentli put circuitry inside the cells to reduce the voltage to 1.5 volts.”

    3. What Haveyou

      Beware that link. Not only is at Amazon-referral spam, but it goes to a NON-RECHARGEABLE battery.

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