Cost of rechqrgeable baatteries vs. alkalines

I mentioned in another thread that rechargeable batteries cost less in the long run, compared to alkaline batts. I sharpened my pencil and tried to figure out the difference. Result.s are startling.

I recently bought eneloop rechargs for a dollar apiece. looking on Amazon, alkies can be had for 65 cents apiece. Rechargs are rated for 1000 cycles, but lets be conservative and say they will give 500 cycles, allowing for loss, etc. Buy a good charged for $40.

For 500 cycles you will pay $41 dollars, plus tax and shipping.

The equivalent in alkys will cost you $325 (500x0.65), a significant difference.

There are a few other costs not considered - the coast of the electricity put into the batteries, the somewhat shorter useful cycle of rechargs, and the cost of replacing equipment probably (hell, certainly) damaged by leaking alkies.

Comments?? Questions??

Great info, thanks Hikemor.

Your last line is the most important reason I use Eneloops, (and a few lithiums).

I have had numerous devices ruined by leaking alkaline batteries before I made the switch. All the alkalines that leaked were well within their expiration dates and kept within operating temperatures. Pricewise, replacing 1 ruined headlamp was more than 2 sets of Eneloops at Costco

The other reasons I use Eneloops are:
*I have to store far fewer batteries
*They are much cheaper in the long run
*They hold a charge for a long time
*With the addition of a solar charger I basically have an unlimited supply of energy.


To give an idea of storage needs I did some calculations:
(All numbers approximate based on 0.57"D AA and 0.41"D AAA)

100 AA alkaline batteries = 5 lbs, 2.25" wide x 14.25" long x 2.0" high (4 rows of 25 batteries)

100 AAA alkaline batteries = 2.5 lbs, 1.75" wide 10.25" long x 1.75" high (4 rows of 25 batteries)

16 AA & 16 AAA Eneloop batteries = 1.2 lbs, 2.25" wide x 3.75" long x 2.0" high (4 rows of 4AA+4AAA)

1 Eneloop AA/AAA charger = 3.4oz, 2.25" wide x 4.5" long x 2.0" high

As listed above I find it much easier, less worrisome, and cheaper, (as Hikemor's numbers show), to store rechargeables.

+1 to reduce damage by leaking alkalines...

This alone makes me want to upgrade all the batteries in my life! Thanks gang!

More environment friendly does it for me. I just hate the idea of disposable things. Ok, will make a exception for TP.

I would also make an exception for feminine hygiene products.

Jeanette Isabelle

I totally agree, Jeanette Isabelle!

I used to travel a lot more than I do now, and used AA alkaline batteries for the SW radio. One thing for AA alkalines, you can find them for sale everywhere. Just swap in the new ones and you are ready to go. Somehow, this fact should be part of their value in any consideration.

If I am near a store, I am near an electrical outlet. If I am in a vehicle, my charger runs off 12V. I can easily platoon sets of batteries in and out of the charger and equipment.

Ideally, my headlamp and GPS, etc., will use the same type of battery, offering further options, if necessary.

My larger Garmin GPS MAP 60 CSx is the one that cannot use lithium primary batteries. This served as motivation for me to invest in Eneloop AA batteries and it's been a good move. I have lithium primary batteries in seldom used but important pieces that are stored in kits. My motivation wasn't so much the environmental concerns but the number of flashlights and other gear wrecked by alkaline batteries.

One specialized application where alkalines are recommended is in avalanche transceiver beacons.

Most modern beacons have a charge indicator. When mine gets below about 80% I change batteries. The problem with rechargeable batteries is that they have a very steep decline curve as they approach the end of a charge. Alkaline batteries have a much more gradual decline of charge over time.

It would not be a good day, if you start a ski tour with your beacon showing a healthy charge, only to have it fall off about the time you or someone in your party get caught in a slide. If someone in your party is buried, and your beacon dies, you don't want to be wasting precious moments changing batteries so you can search for them. If you are the one buried, and your beacon dies, you will likely die too.

For more information on transceiver batteries see Avalanche Beacon Review - Batteries.
To compare batteries, see Battery Test Comparator

What is the typical life of an alkline battery in today's transceivers? I ask because my experience with them was thirty years ago; as I recall, we load them up, hung them around our necks, and left them there for about three weeks...Charge indicators, what are those used for???

When you turn on a modern beacon, it will do a self check and show battery status in bars or percentage.

You can transceive with relatively low battery, but search mode sucks life out of transceive quickly. Batteries are cheap, so I just replace them for each week trip. Not sure if modern ones are more economical then the older ones or not. The new ones have 3 antenna's and digitale processors...

Then i try to use those alkalines in less important things, like bike lights that tend to be stolen here when you leave them on your bike...

The information with both my old transceivers and two I bought three years ago say a set of alkis should last the season.

There are two cases not mentioned:

The first is when you want a detectable loss in performance prior to the total loss of performance. With NiMH batteries, the voltage remains large constant until the end of the battery life, then experience a rapid drop in voltage. Alkalines have a noticeable loss of voltage over the life of the battery. Normally the constant voltage is preferred, but there's not a lot of warning when it dies requiring you to carry spares. This can come as a very unpleasant surprise when using regulated devices like the current generation of pocket lights.

The second is that even with LSD NiMH batteries, the storage life is considerably less then the current generation alkaline batteries. The alkaline will last 5-10 years (in the package) before losing the same capacity as the rechargeable lose in 1 year. For an emergency kit, where you may not be inclined to top off the kit batteries every 6-12 months, alkaline are a the best cost/performance choice.

Easy way of having some spared charged and ready and use the charging moment as a first in - first out rotation from the supply of charged batteries. Just swap the stack with the ones from the emergency kit when you check them.

For long term storage of battery powered items, I usually go to primary lithium batteries - light weight, good in the cold, and they have a looong shelf life.

In practice, I find it easy to switch out batteries before they expire, put them on the charger and they are good to go very soon. and nothing leaks

I have had a lithium primary "leak". Nothing like an alkaline leak/meltdown, but the battery got a tad gunky; the light survived. Never seen any signs of leakage from a NiMH rechargeable.

Thanks for the comparison. I think there is a slight slip in your math.



It seems that this should be 500 cycles per rechargeable (40?).


That would be 500 alkys for each rechargeable bought. That massively tips the scale in favor of the rechargeable.

Inspired by your calculation I did some research and calculation of my own. I found that I could get 1900mAh Eneloops around 2€ a piece (shipping and taxes included) rated for 2100 cycles and Alkalines with compareable capacity for 0.25€ a piece when bought in bulk. The cost for electricity to put in the Eneloop would be around 3€ over the life time allowing for low charger effectivity.
That makes 525€ in alkalines or between 5€(2100 cycles) and 11€(500 cycles) in rechargeables for those 2100 cycles.
With Eneloops it almost makes sense using them in extremely low drain devices like electronic clocks.

The $40 is the hypothetical one time price for the charger.

Ok, I see.
So it is "Buy a good charger for $40." instead of "Buy a good charged for $40.". That makes it much clearer.
I switched to rechargeables quite a bit of time ago. Considering the amount of cells, I have in use, the cost per cell for the charger is almost negligible.

I was surprised to see how much money can be saved by rechargeables...

I am an engineer. We are not easily surprised . However I was pleased with the result of the estimate.
I usually gather boundary conditions, make assumptions if required and run the numbers. I might double check if the result does not match the initial gut feelings.
An additional knock out criterium for the alkalines was the disposal. On some weekends I run through up to 24 AA cells and maybe 1 9V battery for amateur radio equipment. It would literally hurt to haul that amount of cells to the store and throw it into their disposal box (as is the law here) on a weekly basis.

As mentioned in the home kit thread, we're looking at some possibly heavy rain passing through and in case the lights going out, I dropped a CountyComm AAA light in my pocket as a just in case. Pure copper body and you know I didn't use an alkaline battery -- Eneloops only in that light.

You all convinced me. I have a pile of Eneloop AA's and AAA's and a charger coming my way. Thanks everyone!

(And the environment thanks you too)

Another set of leaked alkaline batteries:

I use a programable remote to control my AV setup. I had to reset the DVD last night and so I needed to use the vendor's remote. I hadn't touched the remote in probably two years. Of course the Duracell batteries, that have an expiration date of 3/17, had oozed and caked the unit.

If you're sticking with alkaline batteries don't forget to take them out before you store your equipment.

If you do have a leak white vinegar and Q-tips can be used to remove corrosion.

If you go by/buy today you can get 24 aa or aaa zinc batteries for free.

I use them in cheap flashlights, calculators and old GPS. I have yet to have them
leak (unlike energizer or duracell) and they last as long as rechargeables and about 1/2 the weight.


http://www.harborfreight.com/digitalsavings.html

Q-L,

Do manufacturers offer replacement remote controls?? So frustrating!!!

I have a cottage up north, and everytime we leave we take the time to remove the batteries from the remote controls.

Last year, we actually had an alkaline battery leak while OUTSIDE of the remote!! Luckily we happened to have laid them on a plastic coaster so they wouldn't roll off the fireplace mantle - otherwise the leaking alkaline battery would have damage the mantle finish.

I received my Eneloops and have started using them. Only a week or so into it, but so far so good. Now I just need to make sure that my wife recognizes them as rechargables, and doesn't toss them when they run low!!!!!

Now I find myself wondering if they make a 9V version. So far I only see lithium rechargable 9V batteries.

Hi KenK,

Depending on how old the electronics is a replacement remote can usually be purchased from the manufacturer but depending on the model they can be fairly expensive. I would recommend checking eBay to compare prices.

Eneloops only come in AAA an AA. You can purchase C and D shells that will let you use the AA in devices that use the larger batteries.
http://www.batteryjunction.com/search-results.html?keywords=Eneloop&x=0&y=0

They don't make them in 9v. I did a Google search for "low discharge 9v rechargeable" and got some hits. I haven't used any of them so I'm not going to make a recommendation.

NiMH C cells, at least, are available. Not sure about Ds.

I've got a few NiMH D cells. They take a long time to charge fully. The good news is that unless you use them a lot, you only need to top them up. I have a 3xD lantern and a 3xD Maglite, and I have no idea how long the batteries actually last because they've never died prior to a maintenance charge.

Hi Russ,

Are they low discharge D cells? Would you recommend the manufacturer and what charger you're using?

Thanks

I got them on Amazon:
Odec D Cell Rechargeable Battery, 2-Pack 10000mAh Deep Cycle NiMH Battery
and,
Tenergy D Size 10,000mAh High Capacity High Rate NiMH Rechargeable Batteries

Of the two, the Odec are lower self-discharge and will eventually replace the Tenergy's. The primary reason to get them was to save Maglites from alkaline batteries.

I'm using a Tenergy charger which has four independent bays which can accommodate AAA-D cells. I'm sure there are better chargers but it's what I bought a few years back. Looking at the specs of the T-9688 Super Universal LCD Battery Charger and Tenergy Advanced Universal Charger TN190 , they're only spec'd up to 9000mAh for D cells. That may be why mine never finishes charging the D cells. The Maha PowerEx MH-C808M Charger is rated for 11,000 mAh.

Thanks Russ!