Battery Xtender Alkaline Battery Recharger

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Alkaline battery technology was introduced in the 1950s, and it quickly
became a major part of everyday life. According to a 2004
online report,
approximately three billion household batteries are sold annually in the
United States, "averaging about 32 per family or ten per person." As
stated in this same report, in the year 1992 alone, approximately 101,400
of alkaline batteries were sold. Say it with me now…"GAH!"

Because alkaline batteries are single use items – meaning that they can’t
generally be recharged, it should be safe to say that just about all of
those 101,400 tons eventually wound up in a landfill somewhere. Not
counting disposals from years previous to 1992, and only figuring in disposals
from 1992 to 2004, it could be said that in the past twelve years approximately
1,216,800 tons of alkaline batteries have made their way into
landfills across the country.

In this world of portable gadgets and gizmos, alkaline batteries will
probably continue to be a necessary evil for many years to come. Whether they be
D cells for a flashlight, C cells for a walking robot, AA cells for a portable
CD player, or AAA cells for a remote control, even in this day of rechargeable
batteries there are still plenty of devices that call for the older single-use

Other than the obvious issues that arise when such a massive amount of
non-recyclable waste is disposed, additional environmental concerns have arisen
because of the use of heavy metals in alkaline batteries. Because of those
environmental concerns, both
Energizer and
Duracell have
produced non-Mercury alkaline batteries since the early 1990s. Batteries now
draw their power from the use of steel, zinc and manganese. According to the
Duracell site,
"It is important not to dispose of large amounts of alkaline batteries in a
group. Used batteries are often not completely "dead." Grouping used batteries
together can bring these "live" batteries into contact with one another,
creating safety risks

Well most of us know that there is usually still a little bit of life left in
what we consider a "dead" battery ready for disposal, it just may not be enough
juice to power the electronic device with which we were using it. Once the
battery reaches that lower level of charge, it seems essentially worthless – but
is it? Wouldn’t it be great if there were a way to resuscitate the life back
into an alkaline battery – to bring it back up to a usable level?

The idea of recharging alkaline batteries is not new, but Alkaline battery
chargers have been offered to the public in the past, and they were not very
successful because they did not live up their promise of creating reliable
multi-use batteries from traditional alkaline disposables. I believe that there
are also quite a few people who are reluctant to recharge alkalines because they
believe the company warnings about possible ruptures and leakage if it is

When Think Geek approached us about
reviewing the Battery Xtender Alkaline
Battery Recharger
, because it was a product they might be interested in
carrying, I was skeptical to say the least. I think my first statement was along
the lines of, "Ah, so I get to be the guinea pig?…well, what happens if the
batteries blow up?!" But then curiosity got the best of me, and I agreed to try
it out.

When the Battery Xtender arrived, the first thing I noticed was that it was a
bit larger than the battery chargers I have used in the past, because it was
made to work with D, C, AA and AAA cells. The charger measures approximately
6.5" wide, 5.75" deep, and 2.3" thick and weighs 14.2 ounces.

battery xtender alkaline charger2

As you can see in this picture, there are four battery slots which can slide
up or down to accommodate the various lengths of the different sized cells it
will accept. There is also enough space in between the slots so that fatter
batteries will not touch each other. An included wall charger plugs into a port
on the right side.

According to the included manual, batteries should be checked for corrosion,
leakage or other damage before they are inserted in the Battery Xtender. The
Xtender is for indoor use only and is should be operated in an open area where
air can easily circulate – never in a drawer or confined area. Since there is an
outlet nearby, I decided to use it on the table in our breakfast nook.

The Battery Xtender is composed of an opaque gray plastic body with a
transparent gray plastic flip-lid. The flip-lid is nice and thick which I was
glad to see, because in the back of my mind I thought it might help protect my
table when the batteries began to bubble and leak. Oh ye of little faith…

According to the manual, the Battery Xtender "is designed to recharge
ordinary 1.2 to 1.5-volt alkaline batteries BEFORE they become discharged.
Batteries rated from 1.2 to 1.5 volts can be safely placed in the charger.
Nickel-Cadmium and Nickel-Metal Hydroxide operate between 1.2 and 1.25 volts.
The Battery Xtender cannot recharge an alkaline battery if the battery is dead.
NiCad and other rechargeable batteries recharge more fully when they have first
been fully drained of power. This differs from ordinary alkaline batteries

Now is a good time to mention that the Battery Xtender can be used not only
with alkaline batteries, but also with Nickel Metal Hydroxide (NiMH), Nickel
Cadmium (NiCad), Zinc Carbon, Titanium and Rechargeable Alkaline Manganese
(RAM). There is a note that "Rechargers specifically designed for these types
batteries may provide optimum recharging performance
." However, Lithium
batteries should not be used in the Battery Xtender. Because the Battery Xtender
should only be used with those batteries which properly fit in its bays, meaning
basically that the negative and positive points are on opposite sides and the
battery is long enough to fit in the bay, 9-volt batteries and other oddly
shaped or extra short batteries can not be charged in this device.

Batteries must be inserted with their positive posts against the stationary
top and negative bases against the spring loaded sliding negative contact. AA
and AAA batteries fit in between the spring loaded posts shown below, whereas C
and D cell batteries will press down the spring-loaded posts, indicating to the
Battery Xtender the correct charging current for their size. Any combination of
battery sizes can be used, and one to four batteries can be charged at the same
time. Here you can see a AA battery next to a C cell. Notice how the posts are
pushed in by the width of the larger battery?

battery xtender charger5

Once the batteries are in place and the unit has been plugged in, it’s time
to pay attention to the red, yellow and green LEDs at the base of each battery’s
bay. Red indicates that either the battery has not been properly inserted or it
is dead. Remember that a dead battery can’t be recharged, so it will have to be
discarded. As the following picture shows, a yellow LED will glow to indicate
that the battery is charging. Once charging is complete, the LED will glow
bright green and the current will be automatically shut off going
to that particular battery.

The pictured set of four AA batteries has been used to charge my iPAQ 4700 in

BoxWave Battery Adapter for MiniSync
. Even though the batteries were not
completely discharged, there is a point (around 50%, if the built in gauge is to
be believed) where these batteries just stop charging the power-hungry iPAQ.
Throwing the batteries away at this point would be completely wasteful, as a 50%
battery should still be good for something, just not for what I need it
to do.

Now, according to the Battery Xtender’s manual "it is a good idea to have
two sets of batteries
" that are used for a particular device, "one in use
and the other set recharging
. This will ensure that powerful batteries
are always available and also promote longer battery life
." If 50% life is
as good a place as any to stop using a battery in order to more frequently
charge it, then it would appear that the BoxWave Adapter and the Battery Xtender
might be a match made in heaven.

battery xtender alkaline charger1

According to the
Battery Xtender site
, "The “Battery Xtender”
Alkaline Battery Recharger uses patented microprocessor control techniques to
continuously monitor and control the charging of up to four batteries
simultaneously. There is no temperature rise in the batteries being recharged,
and careful control of the process ensures that there is no buildup of gas or
pressure. Fifteen years of testing and improvement has gone into the development
and as a result the performance has been fine tuned to achieve manifold
increases in the number of times the original energy of the battery may be
recycled through recharging. Other features of the battery charger include
automatic adjustment of the charging currents in proportion to the size of the
batteries being charged. These features have been the subject of additional
patent applications

One thing that slightly surprised me was the amount
of charging time that the Battery Xtender takes. After inserting the batteries,
I assumed that they would be done charging in three to four hours, like regular
rechargeables. However this was not the case. It can take anywhere from 8
to 16 hours to recharge a set of batteries, depending on their amount of
Eventually the Battery Xtender’s LEDs will glow green green,
but since no sound is made it may slip the user’s attention that they are
done charging. Thankfully, each individual bay will automatically
shut off once a full charge is reached, and the alkaline battery will not be

These four AAs took approximately ten hours to fully
recharge. As long as I continue to recharge them before they are completely
discharged (or "dead"), then they should last for multiple charges.
Interestingly enough, it seems as if the recharged batteries are lasting about
as long as they did when new, which I didn’t really think was possible. I am
currently on the sixth cycle of use and recharge – and so far so good! I
am hoping to reach at least ten…

I have used the Battery Xtender with Duracell,
Energizer and Rayovac "non-rechargeable"
batteries. So far, I haven’t run into any snags or issues – other than the
longer than average charging time. Because this product does take a while to
properly charge the batteries without overload, the previously mentioned battery
management practice is key. If there are always a set in the charger that have
just finished recharging, then once I hit a stopping point with the current set
of batteries in a device I can seamlessly perform a swap.

The Battery Xtender has really surprised me because
I didn’t think it was possible to safely recharge alkaline batteries to a
new-new capacity. Now that it has been repeatedly proven to me by this device, I
am happy to recommend it. If you are tired of constantly replacing the alkaline
batteries in your electronic devices, your kids’ toys, or your AV remote
controls, then you should take a look at the Battery Xtender. Not only will it
help lighten the load on your wallet, it will also lighten the load on our

has an excellent video interviewing a Battery Xtender representative, which can
be seen



Product Information

Manufacturer:Battery Xtender
  • Allows multiple quality charges from regular alkaline batteries
  • Shuts off when charge is complete
  • Ecologically sound as it promotes recycling and cells from landfills for a longer period of time
  • Saves the inconvenience and expense of constantly buying new alkalines
  • Takes quite a while to complete a recharge cycle

33 thoughts on “Battery Xtender Alkaline Battery Recharger”

  1. Gadgeteer Comment Policy - Please read before commenting
  2. Stop, Warning — Causes Battery Leaks!!!

    I bought this product, based partly on this review. Before recharging batteries I never experienced any battery leaks. Since using this, I’ve seen about 20 batteries leak. Several have damaged equipment (remote control, telephone headset, flashlight).

    I did nothing unusual. I used the product as directed.

    Most of the batteries are Duracells. The leakage may not occur immediately. I have now recycled all the alkaline batteries, and will never use this charger again.

  3. Hey fellow gadgeteers:
    I received my internet order from the distributor a few days back and have had no issues with battery leakage what so ever. I was seeing 2-packs of AAA batteries in 7-11 (yeah not the cheapest price but aided in my justification of purchase) for CDN$4.99 and thought that despite the one bad review here, the USD$50 was a small gamble to take if I was able to avoid such unnecessary costs. Just to be safe I am charging the batteries with the unit ‘face-down’ so any faulty batteries that escape my ‘eye’ will leak onto the inside of the lid, rather than into the inside of the unit, toasting the charger. I’ll keep you posted if anything ‘noteworthy’ comes about.


    British Columbia, Canada

  4. Brian:

    Thanks for posting and I look forward to any other info that you can provide after you’ve used the charger for awhile.

  5. I’ve also had problems with batteries leaking after charging them with this product. One right in the charger, a couple after I put them in cordless headphones right from the charger, several that had been in a thermostat display for several months.

    The charger had other problems as well. One of the “Adjustable Battery Grips” that holds the battery in place became stuck, and one of the indicator lights (showing the battery is charged) goes green consistently before the others. (It’s possible the grip was damaged by the battery that leaked.)

    I have emailed them twice and have had no response. It’s been a couple weeks…

  6. I left the above comment. (Joyce) I have since talked to Ira, the owner of the company that makes Battery Xtender.

    I’m planning to use his advice and give it another try. His advice: Duracell Ultra and Energizer are good brands to use. Avoid generic types. (The cell walls may be thinner, I believe he said.) He also recommended starting with new batteries, rather than trying to recharge old ones you have around the house, even though they may charge fine.

    About not responding to my emails, he said he’s been having trouble getting some and had missed one from Walmart recently.

    I was able to clean the grip sufficiently to get it working again.

    He offered to replace it if there was a problem other than simple cleaning or adjustment. (I’d have to pay shipping one way.)

    One problem is how to store batteries that you’ve recharged and aren’t using at the moment. (This may have been part of my problem with leakage.) He suggested a product from Home Depot that stores batteries called Battery Rack – SKU 693 252. (He said that you may have to ask for it.) This rack stores 48 AAA and AA batteries and is about $9.95.

    I hope he puts this info on his web site.


  7. I use (and sell) another brand of alkaline battery charger in Australia, and I was very interested to read here about problems with Duracell batteries leaking because we recommend that you don’t recharge Duracell batteries as I, and many others (including a major wholesale battery supplier) have found them the most likely to leak!

    Even without recharging, Duracell seem to leak liquid everywhere if they are left in a device too long – moral, always remove your batteries if the device is not being used for a long time!

    I have had recharged Duracell batteries leak in a device, I’ve had Duracell Ultra leak lying around after recharge and a few of my customers (despite my advise not to) have had Duracell batteries leak in the charger.

    All other brands of batteries I’ve tried (and I’ve tried many different ones*) have had no problem in the charger nor in devices BUT I did have a few which were left lying around for months and develop a white power and a little liquid – moral, check your batteries regularly!

    *some alkaline batteries do perform better after recharging BUT no other brand seemed to leak like Duracell !?!?

    p.s. I have over 5 years of exerience in using an alkaline battery charger (remember not all chargers are the same – my first ‘cheap’ unit from China did cause battery leakage), I now recommend using NiMH batteries with LSD (Low Self Discharge) in high drain applications (e.g. digital cameras), BUT recharged alkalines are fine in LED torches, remote controls, computer wireless devices, electronic gadgets, clocks etc.

  8. Wow, really interesting to read about the ‘battery xtender’. I designed and build and produced the first commercially available alkaline battery recharger in 1993 for the Innovations catalogue – it was called ‘the battery manager’. It too was uP controlled, and the second version had a nice LCD display – sold quite well, but like the Xtender, always had the issue that you will always get some batteries that will leak post recharge, and if that’s in your favourite product, bad press follows – we had one guy use recharged AA’s in a nasal hair trimmer – got stuck up his nose wrapped round some hair – then leaked – that was a bad day ! – I’m still inventing/designing, but bigger things this .. cheers and good luck !

  9. I found these comments highly informative. I have been using “Innovations battery manager Ultra” for over a decade with great success. Anyone else using that?

  10. I have been using the Innovations battery manager Ultra for years also. I have had problems with leaking batteries also – I have not found one brand more or less likely to leak than another. My Ultra has been leaked into many times and I am now having troubles with it recognizing that a battery has been inserted – two of the 4 slots work fine, for tow of the slots, the batteries have to be inserted several times and jostled around for them to be “seen”, and sometimes, they will be cahrging and then I will check them later and that slot will have turned off (as if there were nothing in the slot). As such, I figured the Ultra was on its last legs and I am searching for a new charger – thus my look at the X Tender. If they still made the Ultra, I would buy anohter one – ther are some problems, but overall it’s worthwhile (I have never ruined a device due to a leaking battery – a pain in the tail chore of cleaning up the leakage, but it has never rendered a device unservicable – lucky? possibly.

  11. I Too have been using the Innovations battery manager Ultra for far too many years that i care to remember, It has served me well but I too have to move and juggle the batteries around to get them to register. But I now want a machine that does both rechargable and alkaline as I dont like the idea of having two units for one job, the EverCharge Alkaline + Rechargeable Battery Charger also called the Battery Wizard looks like it ticks all my boxes. Any thoughts on this one?

  12. I had a alkaline battery re-charger several years back, it was all black and made of thick plastic and would charge several batteries at a time. We never had ANY battery leakage with that charger and we charged literally hundreds of alkaline D’s, C’s and AA’s over a 2 year period. We were able to recharge a battery about 8 to 10 times with it and it saved us a LOT of money. I packed it away during a move and still have not found it after arrival at our new place. The only negative thing I noticed was that the batteries would only re-charge to about 4/5 of their original charge length. Even so I still wish I could find that thing again.

  13. I purchased the Battizer charger and I have been very happy. So far I really haven’t seen any leakage and it seems to charge the batteries back to the level they were at when new.

  14. I live in China and was given a replacement battery under the pretense that it was new. However, it only worked a day. When it was replaced with another out of the package battery, I placed it on the battery tester and the needle moves off the scale to the extreme right of “Good”. Should I assume this is a recharged battery? (My clock still doesn’t work, but at this point, I wonder if it’s the clock, or the “new” battery.)

  15. I’ve never used the Xtender, but I do work for the company that distributes the ReZap (which Geo Har posted a link to) in the States. Thanks for posting that, Geo har! I don’t want to shamelessly promote it, but it does actually work, and there shouldn’t be any leakage. Does anybody own one, and have you had any problems with it? Go to to check it out.

  16. Hey fellow Gadgeteers…just an update on this product I purchased back in 2008. I have been using this regularly (complemented with the aid of a voltmeter to keep tabs on overall battery health/storage potential) for two years and have had only *one* issue of a small leak in a battery that I recharged. That is probably less than 1% of the batteries I have repeatedly charged over that time. I use the recharged batteries in LOTS of high-drain devices. Eg: (AA’s) in my Garmin GPS that i take with me into the field for 8+ hrs of use for my work as a plant biologist. Definitely a worthwhile investment for the price paid.



  17. I was using my ‘innovations battery manager ultra’ until my wife and older son decided to move everything into the garage, a Summer event here after about 2005; nothing electronic ever ends up with a power supply . . . and the Voltage/power drain level is not marked. It’s sitting here in the original box, useless. I know it’s an odd voltage or polarity. Can anyone tell me the power supply voltage/spec for this? It’s probably sitting under my nose! Thanks in advance.
    Also, I found Energizer batteries were the worst leakers, no matter the charger. I throw them away. Duracell . . . I had a leak or two, but they were better, I thought. I checked every battery very closely before and after charging, and that helped.

  18. For Jim S

    Just looking on site and saw your comment.

    My Innovations Battery Manager ultra has today finally given up.

    Unfortunately i would send you the adapter packed up ages ago
    Information from the adapter is.

    Model : DB09050
    Input : 230v ~ 50hz
    Output : DC9v – 500ma

    Negative outer part of pin and centre is of course positive.

    I did find that a multi voltage adapter with positive negative reversal switch and multi pins works very well.

    These can be obtained from Maplin Electronics or Ebay.

    Shame Battery Manager is no longer available.

  19. Im an electronics tech of TV, VCR and Ham rigs…you CAN charge alks. But, the companies would rather you BUY new ones and pay $$. Forget that, proper use of a charge, monitor the cells by testing them every few hours with a DMM. once at nominal voltage, remove from chgr, test in device…there are ways to use heat ( 175 degrees ) on alk cells but its dangerous…use a charger and save MONEY!

  20. ALWAYS have good batts on hand, esp for ur flashlights…too many leave lights for years with cheap batts only to find in an emerg. a dead light. I carry an LED light or two since i work nights…Never use a cheapee as its your life u may save. I had to find my way in smoke during a fire and would not be writing this had I not had a good light on me.

  21. I’ve used a device called a BuddyL Supercharger for going on at least 20 years. Before that, I think there was Buddy Charger. It seems like I have doing this for more that 20 years. These have always worked on all kinds of alkaline batteries other that 9V. Did not work on totally dead batteries and eventually would not work on batteries that have been charged many, many times. Sometimes the batteries started to leak but my feeling that this did not happen until the batteries got old. It could take severed hours to charge batteries (4 at a time). Maybe “fast” battery charges heat up the battery too much and cause leaking. I have had almost no problems for all these years. It was a little awkward to get the batteries set in place. After many years, I noticed that it would also charge NiCad batteries but have to push a button to get this to happen. Lately, the charger is not getting the batteries back to full strength. Looking for charger where that batteries can easily be stacked into the device.
    I once decided to use only rechargable nimh batteries but found that they lose their charge too quickly just sitting around. Got tired of charging the same battery over and over without using it in a device. Only alkaline batteries for me from now on.

  22. The Alcaline charger is a old invention. I used one for many years. Then in 2000 the battery makers got aware and changed the formula of the batteries to make them leak when recharged. All the brands that worked fine for years started leaking. Since then I do not use the charger anymore.

  23. I’d really like to try one of these chargers but one thing keeps haunting me. If these are so good for humanity, why are they not readily available in Lowes, Home Depot, Walmart or the corner convenience stores? Is it some great cover up by the Alkaline battery industry or is there a problem with the science?

  24. Like several other posters, my Innovations Battery Manager Ultra has become defective, with one then a second charging bay ceasing to function. Not bad for about 20 years old! I used it mainly as a NiCd/NiMH charger and found it excellent for that. Due presumably to the battery management system it could revive old, apparently dead rechargeables.
    It also worked well as an alkaline battery recharger, within the limits that exist when doing so. I must have recharged at least 150 alkaline batteries, but rarely more than twice as I found relatively little useful charge on the 3rd recharge and an increased tendency to leakage. None bulged or exploded. 2 or 3 leaked in the charger and several leaked in equipment. Was mainly Duracells that leaked and also I found that Duracell Ultras (or some similar enhanced type) would not recharge! Due to the leakage risk I then used them only in moderate to high drain equipment in regular use, like a battery-powered radio used every day and never in remote controls, clocks or torches.
    With the advent of low self-discharge NiMH batteries I will only be buying that type of NiMH in future (2500mAh now available) with Lithium batteries (rather than alkalines) for some equipment – so probably no need for me to buy another alkaline battery charger. Will probably get a decent ‘smart’ standard charger.
    Rayovac once made ‘Rechargeable Alkaline’ batteries that you could charge in any charger, though their own was recommended. Did not lose charge. I still have 2 AAA ones that still work fine after ?10 years. I wonder what happened to that battery technology?

  25. Correction and further info re Rechargeable Alkaline Manganese batteries:
    Are NOT rechargeable on ‘any’ charger though were fine on the Innovations Battery Manager Ultra and the ‘Battery Xtender’ is also compatible.
    RAMs remain available from ‘Pure Energy’ – only maker/seller I could easily find. Main advantage these days is that they give full 1.5 volts which can be important for some equipment.

  26. I have an old “Renewal” Alkaline Battery charger that I got some years ago. I have found it works great at recharging not only Alkaline but also Zinc-carbon (aka “Super Heavy Duty”) cells. I too have seen a lot of leaks from batteries that have been recharged. Surprisingly, the super heavy duty cells seem to respond better and I have not seen them leak. It does seem that Duracell leaks more often.

    However, one thing of special importance is that, with the exception of I believe one or two batteries which leaked in the charger, all of the leaks have happened a substantial amount of time after charging while in storage – in one case I had the batteries sitting on a table in an air conditioned room next to my multi-meter for over a month before they leaked. Most leaks seem to very small, usually just enough to show to flaking white around the terminal(s) when you discover it.

    I also experimented at one point with trying to charge a C battery. My charge only holds AA, so I rigged up a battery holder and wired it through my bread board into a wooden dowel with metal contacts at each end that fit into the charger. The unit just wouldn’t stop charging so after a couple days I was kind of worried that since it wasn’t designed for AA it might overcharge the battery so I swapped it out for a different one (there were 3). Sure enough, even though the battery didn’t get hot one of them did hiss a bit at one point and start to leak so I had to throw it away. The other two I abandoned recharging at this point and put them back in the device, which functioned for several months before the remaining partially recharged batteries finally leaked and died.

  27. I have been using an Innovations Battery Manager since c1995. It is easily the best gadget I have ever bought or used. It recharges all makes & types of battery, regardless of low or high drain use, eg bike lights, remotes, whatever. I don’t know what ‘leak’ means. One year ago one of the four positions stopped working, so I might need to check out a replacement if the other 3 stop too. Energizers probably the best, can recharge up to 10 times. I checked a brand-new Duracell once, before & after recharging, and found it had considerably more charge than as bought !
    Comment for Andy White. Unless the conspiracy theorists are right, why don’t you get off your arse and relaunch ? I know lots of people who would buy one tomorrow.

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