I have been thinging about getting some Nimh AA batts as I go through a lot of them. In the past I have used NiCd but most are used up and the ones that are not are very low capacity (almost used up). I have noticed manufactures claiming how their Nimh batts outperform NiCd and Alkaline. I have always figured and my experence has shown that NiCd has a shorter life then Alk. can Nimh actually outperform alk’s or are these well controlled tests which give Nimh batteries a great advantage. Also do rechargable Alk’s really work?
I use the batts in those motorolla 2 way radios, gps, portable cd player, and portable am/fm radio. The radio I usally use batts that are too week to run the other devices.
We use rechargeable AA alkalines here in a variety of office stuff; they seem to work very well. You need a specific charger.
I think I’m right in saying though that ordinary alkalines could be recharged using a charger for rechargable alkalines (I have a feeling that the guy who invented the system to begin with was using standard alkalines and the battery companies brought out the rechargeable ones in reaction to his idea). I’ve never been brave enough to try.
There might be a difference in the design of the cases for the rechargeable ones though, to make them more durable and resistant to bursting.
I got one of those rechargers ('buddy L’yrs ago) to recharge non-rechargable alks. I didn’t see much of a diff. I finally tried them with the gps which times the total life of the batt (I ajusted for recharging). With no-name (kirkland) alks I get about 19hrs, if I use the alk recharger on hte same batt I can get 23 hrs recharging them after every 4-8 hrs of use (the manufacturer says not to let the alks discharge too far before recharging). - too much effort and wear on the battery door for too little gain.
For Digital Cameras, you really want NiMH batteries. They have the best use characteristics, much better than NiCad and leaps and bounds ahead of Alkalines.
You get an excellent charger, excellent batteries, plus they throw in the car adapter. Buy an extra set of NiMH for another $10 and you’re all set.
I can’t say how the other electronic devices work with NiMH, but because of the way digital cameras draw power this is the way to go for them. Anything else will have significantly shorter useful charge.
The rechargeable alkalines work fine. I’ve got some that are about five years old. They work as long as a fresh pair of alkalines for a year. Then the life span starts to decline. I use the NI-MH for my digital camera now and as my alkalines finally die, they will be replaced with the NI-MH.
My camera says not to use maganese or lithium batteries, as they get to hot and damage the camera.
I don’t know much about the technical aspects behind the whole process, but I can tell you this. I use some Cobra Microtalks with rechargables, and I have tried both Rayovac rechargable alkalines and the energizer Ni-Mh. The Ni-Mh’s last MUUUUUCH longer. It seems to me that the alkalines are more susceptible towards losing power during non-use, especially in colder conditions… But I could be completely wrong.
I do know for sure, though, that in my use the Ni-Mh’s have been infinitely better. I’m pretty sure they’re a much newer technology, aren’t they?
Rog
PS - I actually don’t have many complaints about using the alkalines on my palm, though.
2 way radios take much more power then a palm. I think that is part of it. My feeling from using nicd and disposable alks is that nicd is better in high drain devices while alk’s are better in low drain. I don’t know where the happy medium is nor where the other rechargables fit in. I just got 8 1550mha nimh batts and a slow charger (25h for 1550) If it works out I might get a rapid charger but this one allows me to charge 1,2,3,4 batts instead of 2,4. the 2 way radios use 3 which was a problem w/ my old nicds and old charger
I just bought some rechargeable alkalines cause they were cheap, I mean 6 for about $7.90…
I also saw the NiMH ones & boy are they expensive by comparsion about $5 each. On the box I saw the voltage output of 1.2v; but those rechargeable alkalines output 1.5v.
Also, just look at the package, it gives the rating for them, I think that NiMH were rated 1400amphours & alkalines are 800amphours. Well, I should look again I suppose.
1400 ah for nimh sounds right as they range from 1100 to 1700. I am very supprised that rechar. alks are only 800. For $34.90 I got a charger and 8 nimh 1550ah batts. I thought that was pretty good as it included shipping.
The NI-MH are 1.2 volts each, but have a greater output capacity than alkaline at 1.5 volts each. The NI-MH lose power while not in use, and should be switched from the camera to the charger for a fresh set once in a while. I switch every week, if the camera isn’t used. I can take 82 pictures with flash, motorized focus, and the LCD screen running. I haven’t tried them beyond that point yet. I’m using a 64MB Smartcard, and a 2.3 Megapixel camera. Sometime I’m going to take pictures until the batteries die to see how many I can get on a charge. I’ll take pictures of junk, because the Smartcard can be corrupted when the batteries start to die. It’s pretty important to know how far you can go, when the pictures count.
What type of battery you need is dependant upon what you are using it for. There are different characteristics that you should fit to your individual use.
For a digital camera, you need something that will last a long time on a slow drain, but give you good peaks when needed. For a radio, you just need something that will last on a slow drain. The CD player probably needs a high-drain, but short charge, battery. The GPS would need the same as a radio, very long lasting, but small drain. The walkie-talkies probably need short lasting, but high-drain, batteries. Wish I could remember more about the battery differences, characteristics, and care article in SciAm a few months ago.
I gave up on rechargeable alkalines because if you let the batteries run out all the way, their recharging capacity is greatly diminished (to the point of being almost useless).
Regarding 1.2V NiMh/NiCd vs. 1.5V alkalines, keep in mind that with alkalines, the voltage starts dropping as soon as you start using them. The battery will be considered “dead” once the voltage drops to about .9v, and most battery-powered electronics take this into accound, and are designed to work within this range. Rechargeables (not rechargeable alkalines) pretty much maintain the same voltage until right before they’re about to die. So the average output voltage will be fairly similar to that of alkalines.
Panasonic makes some high-capacity NiCd AA batteries that have almost as much capacity as NiMH (110 mAH) batteries. My 3 year old portable CD player came with a set of these, and they work quite well; I’m still on the original pair and I get about 8-9 hours of play out of them.
I agree that NiMH are the best for digital cameras. I was amazed how fast a set of fresh alkalines died in my Nikon 950 compared with the NiMH batteries.
Harmonious Discord, I have 1600 mAH NiMH batteries and an Olympus D-490, and they have lasted a three-day weekend, filling up a 64 and 32 meg card. This was in winter, so I suspect it would last even longer in summer. Not too many shots were with flash, though.
By the last day the batteries were getting weak and I had to warm them up before use.
Before I thought I’d switch from some aging NiCd’s to Nimh but saw a package of those Panasonic 1100 mAH batt at Costco for about $15 for 8 or even 12, I don’t remember exactly but it was good enough for me to buy a pack. So I used them in mainly 2 way radios and they worked great for a while (much longer then regular NiCd) then they one by one went out (internal short). They didn’t seem to have the recharge cycles that other NiCd batts had maybe 50 on average.
Which is a good thing as when I was thinking about getting the Nimh they ranged from about 1100-1300 mAH now they are up to 1600 and the price has come down.
