Alkaline batteries are much better?

[GregP03]

Sorry if I sound like a newbie, I am when it comes to things like this but I have a question about alkaline batteries. I'm buying a lot of electronic gifts this season and want to know if I should cheap out or if I should buy alkaline batteries. I trust alkaline batteries will give more life over cheaper batteries and are better in almost all regards? Is it the case where you get what you pay for here? Please don't tell me to buy rechargable batteries. These are gifts for people who don't have time for that.

[Leftyretro]

Hi Greg;

There is little no question that alkaline batteries will give much much longer life and be able to supply higher currents then the cheap carbon batteries. In fact some electronics devices must use alkaline because of their high current demand.

As far a price, there is a wide range depending on where and how many you purchase. At a large local membership store I belong too (Costco) they sell AA alkaline for only 34 cents each. The catch? You have to buy them in a 30 piece package.

[jkmadsci]

does anyone know how many mah a typical aa duracell has?

[jeffs555]

http://www.duracell.com/oem/Pdf/others/ATB-full.pdf

Figure 14 near the bottom compares alkaline to carbon-zinc, and shows that Alkaline AA cells have about the same capacity as standard carbon-zinc D cells. The capacity varies greatly with discharge rate, but at 100ma, an AA alkaline has about 2000mAh. I believe I have read that the store brand alkalines are a much better deal than the name brands, close or maybe the same capacity at a much lower price. I usually can buy 10 or more store brand alkalines for the price of 4 name brand, and have never had a problem. Make sure the cells have a good date, as they do have a limited shelf life.

[Bruce Abbott]

Alkalines have greater capacity, but may be equally more expensive. They are useful in applications that need greater power and/or run-time than zinc-carbon, or where long shelf life is important. If you don't mind changing batteries a little more often, it may be more cost-effective to buy the cheapest you can get!

It's strange how dry cells never have the capacity marked on them, almost as if the manufacturers don't want you to know the truth. In fact, Alkalines are not well suited to high-drain applications. Even a 'slow' 1C discharge cuts capacity in half, eg. a Duracell MX1500 AA cell gets about 2100mAH at a discharge rate of 0.125C (0.25A for 8 hours), but only manages 1050mAH at 1C (1A for 1 hour).

[lazy-b]

I like to use Alkaline Battery, because of very low Self discharge rate, This is good for seldomly use equipment like Multimeter, Digital Tester or clock......But for frequently use equipment like Digital Camera, I always use Rechargeable Battery....most NI-CAD and NI-MH rechargeable battery has a self-discharge rate of 1% per day, so even if you do not use it it will discharge in less than 100 days.

Ellion

[jeffs555]

I would agree with everything Bruce said, except the part about carbon-zinc being possibly more cost effective. Maybe prices are skewed differently in NZ. Alkalines generally have about 5 times the capacity of "heavy duty" carbon-zinc, so unless you can buy 5 carbon-zinc for the price of one alkaline, alkalines are more cost effective. I usually get my alkalines from NorthernTool. They sell 24 AA store brand alkalines for $5, and I can't tell any difference between them and the name brands. If you have a local NorthernTool, check them out.

[Hovertime]

If there is IKEA store around they have 10AA packages made by very high quality German company and labeled for ikea for 1.99$

[XJet]

One very interesting aspect of alkaline cells that's not often mentioned is that they are partially rechargable.

So long as you don't over-discharge them (below about half their rated capacity) you can restor about 90% of the previous capacity by recharging.

This generally means you can get about 5-10 recharges into a cell before it's no longer accepts enough charge to make it worthwhile.

If you do allow them to discharge too far before recharging however, you're wasting your time -- they'll not take much charge at all.

The cost savings to be had by recharging alkalines is not insigificant, especially when you factor in their very low price compared to a NiMH of the same capacity. I used to run my personal CD player for about 6 weeks on the same set of AA alkalines before I replaced them with some NiMH cells.

There are some "rechargable" alkalines on the market -- but they're a bit of a waste of money since they charge a premium for them and in reality they're not really much different to the Eveready Energizer or Duracel copper-tops that sell for much less.

[housemuzik]

wow. this was pretty interesting thread. glad i joined up. i actually have an ikea near me. i always thought alkaline was beter but i wasn't sure and i def didn't know how to prove it. i feel smarter now. thanks board!!

house muzik

[GregP03]

Thanks for all the responses everyone. I'm never going to buy those cheapo heavy dutys again. I've learned so much about alkaline batteries in this thread. Xjet, I never knew that about alkaline batteries. That makes alkalines an even better buy.

[dtknowles]

Just a little more useless information. Even the zine/carbon batteries are somewhat rechargeable. Before NiCd's Radio Shack sold rechargers for dry cells and I remember we had one at my folks house. As a child I had a couple small motorized model armored vehicles and I must have recharged the AA cells for those toys a hundred, maybe somewhat less, times. I finally gave up on them when they would not run the tanks long enough to hold my interest.

Tim

[hwhall]

> Even the zine/carbon batteries are somewhat rechargeable. <

I read a piece in a radio mag some years ago about carbon-zinc battery recharging. The author of the article had worked on a flight line in England during WWII where they recharged all the night-shift's flashlight batteries every day. The secrets to success were that they had to be recharged before they ran down very much and the recharge current was low. --Wayne

[XJet]

Actually, I believe that zinc-carbon batteries can be "depolarized", which is somewhat different to recharging insomuch as it's not a reversal of the chemical reaction by which the electricity is generated.

What's more, depolarization only really works on the very cheap (low capacity) zinc-carbon cells since one of the reasons that the heavy-duty cells are "heavy duty" is that they contain additional chemicals that automatically depolarize the cells while they're in use.

[Racinggal6]

From my experience the heavy duty batteries just dont cut it. I spent a ton of money thinking I was getting a good deal. I found myself changing the heavy duty batteries almost on a daily basis. It finally clicked in my blonde brain that I should try alkaline and see if they were any better. Sure enough it lasted alot longer even though I paid a little more. I would definitely stick with the alkaline.

[Jonesy22]

I agree racinggal....I use alkalines in all of my stuff. Especially in my controllers...nothing worse then having your controller go dead in mid flight or race haha